Classification Term: 167920

羧酸 (ontology term: 24e2a074782e1c18144793ab72ac3233)

羧酸

found 82 associated metabolites at sub_class metabolite taxonomy ontology rank level.

Ancestor: 有机酸及其衍生物

Child Taxonomies: 二元羧酸, 芳香族羧酸类, 一元羧酸

Thioctic acid

Viatris brand OF thioctic acid tromethamine

C8H14O2S2 (206.0435)


Lipoate, also known as lipoic acid or 6,8-thioctate, belongs to lipoic acids and derivatives class of compounds. Those are compounds containing a lipoic acid moiety (or a derivative thereof), which consists of a pentanoic acid (or derivative) attached to the C3 carbon atom of a 1,2-dithiolane ring. Lipoate is practically insoluble (in water) and a weakly acidic compound (based on its pKa). Lipoate can be synthesized from octanoic acid. Lipoate can also be synthesized into lipoamide and lipoyl-AMP. Lipoate can be found in broccoli and spinach, which makes lipoate a potential biomarker for the consumption of these food products. Lipoate may be a unique E.coli metabolite. Lipoate is a non-carcinogenic (not listed by IARC) potentially toxic compound. A - Alimentary tract and metabolism > A16 - Other alimentary tract and metabolism products > A16A - Other alimentary tract and metabolism products > A16AX - Various alimentary tract and metabolism products Acquisition and generation of the data is financially supported in part by CREST/JST. D020011 - Protective Agents > D000975 - Antioxidants C26170 - Protective Agent > C275 - Antioxidant D018977 - Micronutrients > D014815 - Vitamins Lipoic acid ((R)-(+)-α-Lipoic acid) is an antioxidant, which is an essential cofactor of mitochondrial enzyme complexes. (R)-(+)-α-Lipoic acid is more effective than racemic Lipoic acid. Lipoic acid ((R)-(+)-α-Lipoic acid) is an antioxidant, which is an essential cofactor of mitochondrial enzyme complexes. (R)-(+)-α-Lipoic acid is more effective than racemic Lipoic acid. α-Lipoic Acid (Thioctic acid) is an antioxidant, which is an essential cofactor of mitochondrial enzyme complexes. α-Lipoic Acid inhibits NF-κB-dependent HIV-1 LTR activation[1][2][3]. α-Lipoic Acid induces endoplasmic reticulum (ER) stress-mediated apoptosis in hepatoma cells[4]. α-Lipoic Acid can be used with CPUL1 (HY-151802) to construct the self-assembled nanoaggregate CPUL1-LA NA, which has improved antitumor efficacy than CPUL1[5]. α-Lipoic Acid (Thioctic acid) is an antioxidant, which is an essential cofactor of mitochondrial enzyme complexes. α-Lipoic Acid inhibits NF-κB-dependent HIV-1 LTR activation[1][2][3]. α-Lipoic Acid induces endoplasmic reticulum (ER) stress-mediated apoptosis in hepatoma cells[4]. α-Lipoic Acid can be used with CPUL1 (HY-151802) to construct the self-assembled nanoaggregate CPUL1-LA NA, which has improved antitumor efficacy than CPUL1[5]. α-Lipoic Acid (Thioctic acid) is an antioxidant, which is an essential cofactor of mitochondrial enzyme complexes. α-Lipoic Acid inhibits NF-κB-dependent HIV-1 LTR activation[1][2][3]. α-Lipoic Acid induces endoplasmic reticulum (ER) stress-mediated apoptosis in hepatoma cells[4]. α-Lipoic Acid can be used with CPUL1 (HY-151802) to construct the self-assembled nanoaggregate CPUL1-LA NA, which has improved antitumor efficacy than CPUL1[5].

   

Shikimic acid

Shikimic acid [3R-(3alpha,4alpha,5beta)]-3,4,5-Trihydroxy-1-cyclohexene-1-carboxylic acid

C7H10O5 (174.0528)


Shikimic acid is a cyclohexenecarboxylic acid that is cyclohex-1-ene-1-carboxylic acid substituted by hydroxy groups at positions 3, 4 and 5 (the 3R,4S,5R stereoisomer). It is an intermediate metabolite in plants and microorganisms. It has a role as an Escherichia coli metabolite, a Saccharomyces cerevisiae metabolite and a plant metabolite. It is a cyclohexenecarboxylic acid, a hydroxy monocarboxylic acid and an alpha,beta-unsaturated monocarboxylic acid. It is a conjugate acid of a shikimate. Shikimic acid is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Shikimic acid is a natural product found in Quercus mongolica, Populus tremula, and other organisms with data available. Shikimic acid is a metabolite found in or produced by Saccharomyces cerevisiae. A tri-hydroxy cyclohexene carboxylic acid important in biosynthesis of so many compounds that the shikimate pathway is named after it. Shikimic acid, more commonly known as its anionic form shikimate, is a cyclohexene, a cyclitol and a cyclohexanecarboxylic acid. It is an important biochemical intermediate in plants and microorganisms. Its name comes from the Japanese flower shikimi (the Japanese star anise, Illicium anisatum), from which it was first isolated. Shikimic acid is a precursor for: the aromatic amino acids phenylalanine and tyrosine; indole, indole derivatives and tryptophan; many alkaloids and other aromatic metabolites; tannins; and lignin. In pharmaceutical industry, shikimic acid from chinese star anise is used as a base material for production of Tamiflu (oseltamivir). Although shikimic acid is present in most autotrophic organisms, it is a biosynthetic intermediate and generally found in very low concentrations. A cyclohexenecarboxylic acid that is cyclohex-1-ene-1-carboxylic acid substituted by hydroxy groups at positions 3, 4 and 5 (the 3R,4S,5R stereoisomer). It is an intermediate metabolite in plants and microorganisms. Acquisition and generation of the data is financially supported in part by CREST/JST. CONFIDENCE standard compound; INTERNAL_ID 175 KEIO_ID S012 Shikimic acid is a key metabolic intermediate of the aromatic amino acid biosynthesis pathway, found in microbes and plants. Shikimic acid is a key metabolic intermediate of the aromatic amino acid biosynthesis pathway, found in microbes and plants.

   

Citric acid

2-hydroxypropane-1,2,3-tricarboxylic acid

C6H8O7 (192.027)


Citric acid (citrate) is a tricarboxylic acid, an organic acid with three carboxylate groups. Citrate is an intermediate in the TCA cycle (also known as the Tricarboxylic Acid cycle, the Citric Acid cycle or Krebs cycle). The TCA cycle is a central metabolic pathway for all animals, plants, and bacteria. As a result, citrate is found in all living organisms, from bacteria to plants to animals. In the TCA cycle, the enzyme citrate synthase catalyzes the condensation of oxaloacetate with acetyl CoA to form citrate. Citrate then acts as the substrate for the enzyme known as aconitase and is then converted into aconitic acid. The TCA cycle ends with regeneration of oxaloacetate. This series of chemical reactions in the TCA cycle is the source of two-thirds of the food-derived energy in higher organisms. Citrate can be transported out of the mitochondria and into the cytoplasm, then broken down into acetyl-CoA for fatty acid synthesis, and into oxaloacetate. Citrate is a positive modulator of this conversion, and allosterically regulates the enzyme acetyl-CoA carboxylase, which is the regulating enzyme in the conversion of acetyl-CoA into malonyl-CoA (the commitment step in fatty acid synthesis). In short, citrate is transported into the cytoplasm, converted into acetyl CoA, which is then converted into malonyl CoA by acetyl CoA carboxylase, which is allosterically modulated by citrate. In mammals and other vertebrates, Citrate is a vital component of bone, helping to regulate the size of apatite crystals (PMID: 21127269). Citric acid is found in citrus fruits, most concentrated in lemons and limes, where it can comprise as much as 8\\\\\% of the dry weight of the fruit. Citric acid is a natural preservative and is also used to add an acidic (sour) taste to foods and carbonated drinks. Because it is one of the stronger edible acids, the dominant use of citric acid is as a flavoring and preservative in food and beverages, especially soft drinks and candies. Citric acid is an excellent chelating agent, binding metals by making them soluble. It is used to remove and discourage the buildup of limescale from boilers and evaporators. It can be used to treat water, which makes it useful in improving the effectiveness of soaps and laundry detergents. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium chelating ability. Intolerance to citric acid in the diet is known to exist. Little information is available as the condition appears to be rare, but like other types of food intolerance it is often described as a "pseudo-allergic" reaction. Citric acid appears as colorless, odorless crystals with an acid taste. Denser than water. (USCG, 1999) Citric acid is a tricarboxylic acid that is propane-1,2,3-tricarboxylic acid bearing a hydroxy substituent at position 2. It is an important metabolite in the pathway of all aerobic organisms. It has a role as a food acidity regulator, a chelator, an antimicrobial agent and a fundamental metabolite. It is a conjugate acid of a citrate(1-) and a citrate anion. A key intermediate in metabolism. It is an acid compound found in citrus fruits. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium-chelating ability. Citric acid is one of the active ingredients in Phexxi, a non-hormonal contraceptive agent that was approved by the FDA on May 2020. It is also used in combination with magnesium oxide to form magnesium citrate, an osmotic laxative. Citric acid is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Anhydrous citric acid is a Calculi Dissolution Agent and Anti-coagulant. The mechanism of action of anhydrous citric acid is as an Acidifying Activity and Calcium Chelating Activity. The physiologic effect of anhydrous citric acid is by means of Decreased Coagulation Factor Activity. Anhydrous Citric Acid is a tricarboxylic acid found in citrus fruits. Citric acid is used as an excipient in pharmaceutical preparations due to its antioxidant properties. It maintains stability of active ingredients and is used as a preservative. It is also used as an acidulant to control pH and acts as an anticoagulant by chelating calcium in blood. A key intermediate in metabolism. It is an acid compound found in citrus fruits. The salts of citric acid (citrates) can be used as anticoagulants due to their calcium chelating ability. See also: Citric Acid Monohydrate (related). Citrate, also known as anhydrous citric acid or 2-hydroxy-1,2,3-propanetricarboxylic acid, belongs to tricarboxylic acids and derivatives class of compounds. Those are carboxylic acids containing exactly three carboxyl groups. Citrate is soluble (in water) and a weakly acidic compound (based on its pKa). Citrate can be found in a number of food items such as ucuhuba, loquat, bayberry, and longan, which makes citrate a potential biomarker for the consumption of these food products. Citrate can be found primarily in most biofluids, including saliva, sweat, feces, and blood, as well as throughout all human tissues. Citrate exists in all living species, ranging from bacteria to humans. In humans, citrate is involved in several metabolic pathways, some of which include the oncogenic action of succinate, the oncogenic action of fumarate, the oncogenic action of 2-hydroxyglutarate, and congenital lactic acidosis. Citrate is also involved in several metabolic disorders, some of which include 2-ketoglutarate dehydrogenase complex deficiency, pyruvate dehydrogenase deficiency (E2), fumarase deficiency, and glutaminolysis and cancer. Moreover, citrate is found to be associated with lung Cancer, tyrosinemia I, maple syrup urine disease, and propionic acidemia. A citrate is a derivative of citric acid; that is, the salts, esters, and the polyatomic anion found in solution. An example of the former, a salt is trisodium citrate; an ester is triethyl citrate. When part of a salt, the formula of the citrate ion is written as C6H5O73− or C3H5O(COO)33− . A tricarboxylic acid that is propane-1,2,3-tricarboxylic acid bearing a hydroxy substituent at position 2. It is an important metabolite in the pathway of all aerobic organisms. Citric acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=77-92-9 (retrieved 2024-07-01) (CAS RN: 77-92-9). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Citric acid is a natural preservative and food tartness enhancer. Citric acid induces apoptosis and cell cycle arrest at G2/M phase and S phase in HaCaT cells. Citric acid cause oxidative damage of the liver by means of the decrease of antioxidative enzyme activities. Citric acid causes renal toxicity in mice[1][2][3]. Citric acid is a natural preservative and food tartness enhancer. Citric acid induces apoptosis and cell cycle arrest at G2/M phase and S phase in HaCaT cells. Citric acid cause oxidative damage of the liver by means of the decrease of antioxidative enzyme activities. Citric acid causes renal toxicity in mice[1][2][3].

   

Succinic acid

butanedioic acid

C4H6O4 (118.0266)


Succinic acid appears as white crystals or shiny white odorless crystalline powder. pH of 0.1 molar solution: 2.7. Very acid taste. (NTP, 1992) Succinic acid is an alpha,omega-dicarboxylic acid resulting from the formal oxidation of each of the terminal methyl groups of butane to the corresponding carboxy group. It is an intermediate metabolite in the citric acid cycle. It has a role as a nutraceutical, a radiation protective agent, an anti-ulcer drug, a micronutrient and a fundamental metabolite. It is an alpha,omega-dicarboxylic acid and a C4-dicarboxylic acid. It is a conjugate acid of a succinate(1-). A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawleys Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851) Succinic acid is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). Succinic acid is a dicarboxylic acid. The anion, succinate, is a component of the citric acid cycle capable of donating electrons to the electron transfer chain. Succinic acid is created as a byproduct of the fermentation of sugar. It lends to fermented beverages such as wine and beer a common taste that is a combination of saltiness, bitterness and acidity. Succinate is commonly used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. Succinate plays a role in the citric acid cycle, an energy-yielding process and is metabolized by succinate dehydrogenase to fumarate. Succinate dehydrogenase (SDH) plays an important role in the mitochondria, being both part of the respiratory chain and the Krebs cycle. SDH with a covalently attached FAD prosthetic group, binds enzyme substrates (succinate and fumarate) and physiological regulators (oxaloacetate and ATP). Oxidizing succinate links SDH to the fast-cycling Krebs cycle portion where it participates in the breakdown of acetyl-CoA throughout the whole Krebs cycle. Succinate can readily be imported into the mitochondrial matrix by the n-butylmalonate- (or phenylsuccinate-) sensitive dicarboxylate carrier in exchange with inorganic phosphate or another organic acid, e.g. malate. (A3509) Mutations in the four genes encoding the subunits of succinate dehydrogenase are associated with a wide spectrum of clinical presentations (i.e.: Huntingtons disease. (A3510). Succinate also acts as an oncometabolite. Succinate inhibits 2-oxoglutarate-dependent histone and DNA demethylase enzymes, resulting in epigenetic silencing that affects neuroendocrine differentiation. A water-soluble, colorless crystal with an acid taste that is used as a chemical intermediate, in medicine, the manufacture of lacquers, and to make perfume esters. It is also used in foods as a sequestrant, buffer, and a neutralizing agent. (Hawleys Condensed Chemical Dictionary, 12th ed, p1099; McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1851) Succinic acid (succinate) is a dicarboxylic acid. It is an important component of the citric acid or TCA cycle and is capable of donating electrons to the electron transfer chain. Succinate is found in all living organisms ranging from bacteria to plants to mammals. In eukaryotes, succinate is generated in the mitochondria via the tricarboxylic acid cycle (TCA). Succinate can readily be imported into the mitochondrial matrix by the n-butylmalonate- (or phenylsuccinate-) sensitive dicarboxylate carrier in exchange with inorganic phosphate or another organic acid, e. g. malate (PMID 16143825). Succinate can exit the mitochondrial matrix and function in the cytoplasm as well as the extracellular space. Succinate has multiple biological roles including roles as a metabolic intermediate and roles as a cell signalling molecule. Succinate can alter gene expression patterns, thereby modulating the epigenetic landscape or it can exhibit hormone-like signaling functions (PMID: 26971832). As such, succinate links cellular metabolism, especially ATP formation, to the regulation of cellular function. Succinate can be broken down or metabolized into fumarate by the enzyme succinate dehydrogenase (SDH), which is part of the electron transport chain involved in making ATP. Dysregulation of succinate synthesis, and therefore ATP synthesis, can happen in a number of genetic mitochondrial diseases, such as Leigh syndrome, and Melas syndrome. Succinate has been found to be associated with D-2-hydroxyglutaric aciduria, which is an inborn error of metabolism. Succinic acid has recently been identified as an oncometabolite or an endogenous, cancer causing metabolite. High levels of this organic acid can be found in tumors or biofluids surrounding tumors. Its oncogenic action appears to due to its ability to inhibit prolyl hydroxylase-containing enzymes. In many tumours, oxygen availability becomes limited (hypoxia) very quickly due to rapid cell proliferation and limited blood vessel growth. The major regulator of the response to hypoxia is the HIF transcription factor (HIF-alpha). Under normal oxygen levels, protein levels of HIF-alpha are very low due to constant degradation, mediated by a series of post-translational modification events catalyzed by the prolyl hydroxylase domain-containing enzymes PHD1, 2 and 3, (also known as EglN2, 1 and 3) that hydroxylate HIF-alpha and lead to its degradation. All three of the PHD enzymes are inhibited by succinate. In humans, urinary succinic acid is produced by Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Enterobacter, Acinetobacter, Proteus mirabilis, Citrobacter frundii, Enterococcus faecalis (PMID: 22292465). Succinic acid is also found in Actinobacillus, Anaerobiospirillum, Mannheimia, Corynebacterium and Basfia (PMID: 22292465; PMID: 18191255; PMID: 26360870). Succinic acid is widely distributed in higher plants and produced by microorganisms. It is found in cheeses and fresh meats. Succinic acid is a flavouring enhancer, pH control agent [DFC]. Succinic acid is also found in yellow wax bean, swamp cabbage, peanut, and abalone. An alpha,omega-dicarboxylic acid resulting from the formal oxidation of each of the terminal methyl groups of butane to the corresponding carboxy group. It is an intermediate metabolite in the citric acid cycle. COVID info from PDB, Protein Data Bank Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID S004 Succinic acid is a potent and orally active anxiolytic agent. Succinic acid is an intermediate product of the tricarboxylic acid cycle. Succinic acid can be used as a precursor of many industrially important chemicals in food, chemical and pharmaceutical industries[1][2]. Succinic acid is a potent and orally active anxiolytic agent. Succinic acid is an intermediate product of the tricarboxylic acid cycle. Succinic acid can be used as a precursor of many industrially important chemicals in food, chemical and pharmaceutical industries[1][2].

   

D-Malic acid

(2R)-2-HYDROXYBUTANEDIOIC ACID; 2-HYDROXY-SUCCINIC ACID

C4H6O5 (134.0215)


(R)-malic acid is an optically active form of malic acid having (R)-configuration. It is a conjugate acid of a (R)-malate(2-). It is an enantiomer of a (S)-malic acid. (R)-Malate is a metabolite found in or produced by Escherichia coli (strain K12, MG1655). D-malate is a natural product found in Vaccinium macrocarpon, Pogostemon cablin, and other organisms with data available. D-Malic acid is found in herbs and spices. This enantiomer of rare occurrence; reported from fruits and leaves of Hibiscus sabdariffa (roselle) although there are many more isolations of malic acid with no opt. rotn. given and some may be of the R-for An optically active form of malic acid having (R)-configuration. COVID info from PDB, Protein Data Bank Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS Acquisition and generation of the data is financially supported in part by CREST/JST. D-(+)-Malic acid (D-Malic acid), an active enantiomer of Malic acid, is a competitive inhibitor of L(--)malic acid transport[1]. D-(+)-Malic acid (D-Malic acid), an active enantiomer of Malic acid, is a competitive inhibitor of L(--)malic acid transport[1].

   

2-Isopropylmalic acid

(2S)-2-Hydroxy-2-(1-methylethyl)butanedioic acid

C7H12O5 (176.0685)


2-Isopropylmalic acid (CAS: 3237-44-3), also known as 3-carboxy-3-hydroxyisocaproic acid, belongs to the class of organic compounds known as hydroxy fatty acids. These are fatty acids in which the chain bears a hydroxyl group. 2-Isopropylmalic acid is a very hydrophobic molecule, practically insoluble (in water), and relatively neutral. 2-Isopropylmalic acid is an alpha-hydroxy organic acid regularly occurring in the urine of healthy individuals (PMID: 2338430, 544608), and in hemofiltrates (PMID: 7251751). 2-Isopropylmalic acid is elevated during fasting and diabetic ketoacidosis (PMID: 1591279). It is also a metabolite found in Acetobacter (PMID: 6035258). α-Isopropylmalate (α-IPM) is the leucine biosynthetic precursor in Yeast[1]. α-Isopropylmalate. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=3237-44-3 (retrieved 2024-08-26) (CAS RN: 3237-44-3). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).

   

3-Hydroxyisovaleric acid

beta-Hydroxy-beta-methylbutyric acid

C5H10O3 (118.063)


3-Hydroxyisovaleric acid is a normal human metabolite excreted in the urine. It is a byproduct of the leucine degradation pathway. Production of 3-hydroxyisovaleric acid begins with the conversion of 3-methylcrotonyl-CoA into 3-methylglutaconyl-CoA in the mitochondria by the biotin-dependent enzyme methylcrotonyl-CoA carboxylase. Biotin deficiencies, certain lifestyle habits (smoking), or specific genetic conditions can reduce methylcrotonyl-CoA carboxylase activity. This reduction can lead to a buildup of 3-methylcrotonyl-CoA, which is converted into 3-hydroxyisovaleryl-CoA by the enzyme enoyl-CoA hydratase. Increased concentrations of 3-methylcrotonyl-CoA and 3-hydroxyisovaleryl-CoA can lead to a disruption of the esterified CoA:free CoA ratio, and ultimately to mitochondrial toxicity. Detoxification of these metabolic end products occur via the transfer of the 3-hydroxyisovaleryl moiety to carnitine forming 3-hydroxyisovaleric acid-carnitine or 3HIA-carnitine, which is then transferred across the inner mitochondrial membrane where 3-hydroxyisovaleric acid is released as the free acid (PMID: 21918059). 3-Hydroxyisovaleric acid has been found to be elevated in smokers and in subjects undergoing long-term anticonvulsant therapy with carbamazepine and/or phenytoin. These levels are elevated due to impairment of renal reclamation of biotin. Levels may also be increased from prolonged consumption of raw egg-whites (PMID: 16895887, 9523856, 15447901, 9176832) (OMIM: 210210, 253270, 600529, 253260, 246450, 210200, 238331). When present in sufficiently high levels, 3-hydroxyisovaleric acid can act as an acidogen and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of 3-hydroxyisovaleric acid are associated with at least a dozen inborn errors of metabolism, including 3-hydroxy-3-methylglutaryl-CoA lyase deficiency, 3-methylglutaconic aciduria type I, biotinidase deficiency and isovaleric aciduria, dihydrolipoamide dehydrogenase deficiency, 3-methylcrotonyl-CoA carboxylase 1 deficiency, 3-hydroxy-3-methylglutaryl-CoA lyase deficiency, late-onset multiple carboxylase deficiency, holocarboxylase synthetase deficiency, and 3-methylcrotonyl-CoA carboxylase 2 deficiency. 3-Hydroxyisovaleric acid is an organic acid. Abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart, liver, and kidney abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of the untreated IEMs mentioned above. Many affected children with organic acidemias experience intellectual disability or delayed development. In adults, acidosis or acidemia is characterized by headaches, confusion, feeling tired, tremors, sleepiness, and seizures. 3-Hydroxyisovaleric acid is a normal human metabolite excreted in the urine. Elevated levels of this compound are found in several inherited disorders such as Dihydrolipoamide dehydrogenase Deficiency, 3-Methylcrotonyl-CoA carboxylase 1 deficiency, 3-Hydroxy-3-methylglutaryl-CoA lyase deficiency (3-hydroxy-3-methylglutaryl -CoA lyase Deficiency, Biotinidase deficiency multiple carboxylase deficiency late-onset , Late onset multiple carboxylase deficiency, HolMcarboxylase synthetase deficiency, 3-Methylcrotonyl-CoA carboxylase 2 deficiency. 3-Hydroxyisovaleric acid is also elevated in smokers, in subjects undergoing long-term anticonvulsant therapy with carbamazepine and/or phenytoin. These levels are elevated due to impairment of renal reclamation of biotin. Levels may also be increased from prolonged consumption of raw egg-whites (PMID: 16895887, 9523856, 15447901, 9176832)(OMIM: 210210, 253270, 600529, 253260, 246450, 210200, 238331) [HMDB] 3-Hydroxyisovaleric acid is a normal endogenous metabolite excreted in the urine. The urinary excretion of 3-hydroxyisovaleric acid is early and sensitive indicator of biotin deficiency[1][2]. 3-Hydroxyisovaleric acid is a normal endogenous metabolite excreted in the urine. The urinary excretion of 3-hydroxyisovaleric acid is early and sensitive indicator of biotin deficiency[1][2].

   

3-Hydroxybutyric acid

(R)-(-)-beta-Hydroxybutyric acid

C4H8O3 (104.0473)


3-Hydroxybutyric acid (CAS: 300-85-6), also known as beta-hydroxybutanoic acid, is a typical partial-degradation product of branched-chain amino acids (primarily valine) released from muscle for hepatic and renal gluconeogenesis. This acid is metabolized by 3-hydroxybutyrate dehydrogenase (catalyzes the oxidation of 3-hydroxybutyrate to form acetoacetate, using NAD+ as an electron acceptor). The enzyme functions in nervous tissues and muscles, enabling the use of circulating hydroxybutyrate as a fuel. In the liver mitochondrial matrix, the enzyme can also catalyze the reverse reaction, a step in ketogenesis. 3-Hydroxybutyric acid is a chiral compound having two enantiomers, D-3-hydroxybutyric acid and L-3-hydroxybutyric acid, and is a ketone body. Like the other ketone bodies (acetoacetate and acetone), levels of 3-hydroxybutyrate in blood and urine are raised in ketosis. In humans, 3-hydroxybutyrate is synthesized in the liver from acetyl-CoA and can be used as an energy source by the brain when blood glucose is low. Blood levels of 3-hydroxybutyric acid levels may be monitored in diabetic patients to look for diabetic ketoacidosis. Persistent mild hyperketonemia is a common finding in newborns. Ketone bodies serve as an indispensable source of energy for extrahepatic tissues, especially the brain and lung of developing mammals. Another important function of ketone bodies is to provide acetoacetyl-CoA and acetyl-CoA for the synthesis of cholesterol, fatty acids, and complex lipids. During the early postnatal period, acetoacetate (AcAc) and beta-hydroxybutyrate are preferred over glucose as substrates for the synthesis of phospholipids and sphingolipids in accord with requirements for brain growth and myelination. Thus, during the first two weeks of postnatal development, when the accumulation of cholesterol and phospholipids accelerates, the proportion of ketone bodies incorporated into these lipids increases. On the other hand, an increased proportion of ketone bodies is utilized for cerebroside synthesis during the period of active myelination. In the lung, AcAc serves better than glucose as a precursor for the synthesis of lung phospholipids. The synthesized lipids, particularly dipalmitoylphosphatidylcholine, are incorporated into surfactant, and thus have a potential role in supplying adequate surfactant lipids to maintain lung function during the early days of life (PMID: 3884391). 3-Hydroxybutyric acid is found to be associated with fumarase deficiency and medium-chain acyl-CoA dehydrogenase deficiency, which are inborn errors of metabolism. 3-Hydroxybutyric acid is a metabolite of Alcaligenes and can be produced from plastic metabolization or incorporated into polymers, depending on the species (PMID: 7646009, 18615882). (R)-3-Hydroxybutyric acid is a butyric acid substituted with a hydroxyl group in the beta or 3 position. It is involved in the synthesis and degradation of ketone bodies. Like the other ketone bodies (acetoacetate and acetone), levels of beta-hydroxybutyrate are raised in the blood and urine in ketosis. Beta-hydroxybutyrate is a typical partial-degradation product of branched-chain amino acids (primarily valine) released from muscle for hepatic and renal gluconeogenesis This acid is metabolized by 3-hydroxybutyrate dehydrogenase (catalyzes the oxidation of D-3-hydroxybutyrate to form acetoacetate, using NAD+ as an electron acceptor). The enzyme functions in nervous tissues and muscles, enabling the use of circulating hydroxybutyrate as a fuel. In the liver mitochondrial matrix, the enzyme can also catalyze the reverse reaction, a step in ketogenesis. 3-Hydroxybutyric acid is a chiral compound having two enantiomers, D-3-hydroxybutyric acid and L-3-hydroxybutyric acid. In humans, beta-hydroxybutyrate is synthesized in the liver from acetyl-CoA, and can be used as an energy source by the brain when blood glucose is low. It can also be used for the synthesis of biodegradable plastics . [HMDB] Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID H022 (R)-3-Hydroxybutanoic acid is a metabolite, and converted from acetoacetic acid catalyzed by 3-hydroxybutyrate dehydrogenase. (R)-3-Hydroxybutanoic acid has applications as a nutrition source and as a precursor for vitamins, antibiotics and pheromones[1][2]. 3-Hydroxybutyric acid (β-Hydroxybutyric acid) is a metabolite that is elevated in type I diabetes. 3-Hydroxybutyric acid can modulate the properties of membrane lipids[1]. 3-Hydroxybutyric acid (β-Hydroxybutyric acid) is a metabolite that is elevated in type I diabetes. 3-Hydroxybutyric acid can modulate the properties of membrane lipids[1].

   

5-Aminopentanoic acid

5-Aminovaleric acid hydrochloride

C5H11NO2 (117.079)


5-Aminopentanoic acid (or 5-aminovalerate) is a lysine degradation product. It can be produced both endogenously or through bacterial catabolism of lysine. 5-aminovalerate is formed via the following multi-step reaction: L-lysine leads to cadverine leads to L-piperideine leads 5-aminovalerate (PMID:405455). In other words it is a metabolite of cadaverine which is formed via the intermediate, 1-piperideine (PMID:6436440). Cadaverine is a foul-smelling diamine compound produced by protein hydrolysis during putrefaction of animal tissue. High levels of 5-aminovalerate in biofluids may indicate bacterial overgrowth or endogenous tissue necrosis. In most cases endogenous 5-aminovalerate is thought to be primarily a microbial metabolite produced by the gut or oral microflora, although it can be produced endogenously. 5-aminovalerate is a normal metabolite present in human saliva, with a tendency to elevated concentration in patients with chronic periodontitis. Bacterial contamination and decomposition of salivary proteins is primarily responsible for elevated salivary levels (PMID 3481959). Beyond being a general waste product, 5-aminovalerate is also believed to act as a methylene homologue of gamma-aminobutyric acid (GABA) and functions as a weak GABA agonist (PMID:4031870). It is also known as an antifibrinolytic amino acid analog and so it functions as a weak inhibitor of the blood clotting pathway (PMID:6703712). 5- aminovalerate is an in vivo substrate of 4-aminobutyrate:2-oxoglutarate aminotransferase (PMID:4031870). It can be found in Corynebacterium (PMID:27717386). 5-aminopentanoic acid is a normal metabolite present in human saliva, with a tendency to elevated concentration in patients with chronic periodontitis. Bacterial contamination and decomposition of salivary proteins is responsible for the elevated salivary levels (PMID 3481959) [HMDB] 5-Aminovaleric acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=660-88-8 (retrieved 2024-07-17) (CAS RN: 660-88-8). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). 5-Aminovaleric acid is believed to act as a methylene homologue of gamma-aminobutyric acid (GABA) and functions as a weak GABA agonist.

   

Oxoglutaric acid

2-oxopentanedioic acid

C5H6O5 (146.0215)


Oxoglutaric acid, also known as alpha-ketoglutarate, alpha-ketoglutaric acid, AKG, or 2-oxoglutaric acid, is classified as a gamma-keto acid or a gamma-keto acid derivative. gamma-Keto acids are organic compounds containing an aldehyde substituted with a keto group on the C4 carbon atom. alpha-Ketoglutarate is considered to be soluble (in water) and acidic. alpha-Ketoglutarate is a key molecule in the TCA cycle, playing a fundamental role in determining the overall rate of this important metabolic process (PMID: 26759695). In the TCA cycle, AKG is decarboxylated to succinyl-CoA and carbon dioxide by AKG dehydrogenase, which functions as a key control point of the TCA cycle. Additionally, AKG can be generated from isocitrate by oxidative decarboxylation catalyzed by the enzyme known as isocitrate dehydrogenase (IDH). In addition to these routes of production, AKG can be produced from glutamate by oxidative deamination via glutamate dehydrogenase, and as a product of pyridoxal phosphate-dependent transamination reactions (mediated by branched-chain amino acid transaminases) in which glutamate is a common amino donor. AKG is a nitrogen scavenger and a source of glutamate and glutamine that stimulates protein synthesis and inhibits protein degradation in muscles. In particular, AKG can decrease protein catabolism and increase protein synthesis to enhance bone tissue formation in skeletal muscles (PMID: 26759695). Interestingly, enteric feeding of AKG supplements can significantly increase circulating plasma levels of hormones such as insulin, growth hormone, and insulin-like growth factor-1 (PMID: 26759695). It has recently been shown that AKG can extend the lifespan of adult C. elegans by inhibiting ATP synthase and TOR (PMID: 24828042). In combination with molecular oxygen, alpha-ketoglutarate is required for the hydroxylation of proline to hydroxyproline in the production of type I collagen. A recent study has shown that alpha-ketoglutarate promotes TH1 differentiation along with the depletion of glutamine thereby favouring Treg (regulatory T-cell) differentiation (PMID: 26420908). alpha-Ketoglutarate has been found to be associated with fumarase deficiency, 2-ketoglutarate dehydrogenase complex deficiency, and D-2-hydroxyglutaric aciduria, which are all inborn errors of metabolism (PMID: 8338207). Oxoglutaric acid has been found to be a metabolite produced by Corynebacterium and yeast (PMID: 27872963) (YMDB). [Spectral] 2-Oxoglutarate (exact mass = 146.02152) and S-Adenosyl-L-homocysteine (exact mass = 384.12159) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. [Spectral] 2-Oxoglutarate (exact mass = 146.02152) and (S)-Malate (exact mass = 134.02152) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Flavouring ingredient

   

Aminoadipic acid

(2S)-2-Azaniumyl-6-hydroxy-6-oxohexanoate

C6H11NO4 (161.0688)


Aminoadipic acid (CAS: 542-32-5), also known as 2-aminoadipate, is a metabolite in the principal biochemical pathway of lysine. It is an intermediate in the metabolism (i.e. breakdown or degradation) of lysine and saccharopine. It antagonizes neuroexcitatory activity modulated by the glutamate receptor N-methyl-D-aspartate (NMDA). Aminoadipic acid has also been shown to inhibit the production of kynurenic acid, a broad spectrum excitatory amino acid receptor antagonist, in brain tissue slices (PMID: 8566117). Recent studies have shown that aminoadipic acid is elevated in prostate biopsy tissues from prostate cancer patients (PMID: 23737455). Mutations in DHTKD1 (dehydrogenase E1 and transketolase domain-containing protein 1) have been shown to cause human 2-aminoadipic aciduria and 2-oxoadipic aciduria via impaired decarboxylation of 2-oxoadipate to glutaryl-CoA, which is the last step in the lysine degradation pathway (PMID: 23141293). Aging, diabetes, sepsis, and renal failure are known to catalyze the oxidation of lysyl residues to form 2-aminoadipic acid in human skin collagen and potentially other tissues (PMID: 18448817). Proteolytic breakdown of these tissues can lead to the release of free 2-aminoadipic acid. Studies in rats indicate that aminoadipic acid (along with the three branched-chain amino acids: leucine, valine, and isoleucine) levels are elevated in the pre-diabetic phase and so aminoadipic acid may serve as a predictive biomarker for the development of diabetes (PMID: 15389298). Long-term hyperglycemia of endothelial cells can also lead to elevated levels of aminoadipate which is thought to be a sign of lysine breakdown through oxidative stress and reactive oxygen species (ROS) (PMID: 21961526). 2-Aminoadipate is a potential small-molecule marker of oxidative stress (PMID: 21647514). Therefore, depending on the circumstances aminoadipic acid can act as an acidogen, a diabetogen, an atherogen, and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A diabetogen is a compound that can lead to type 2 diabetes. An atherogen is a compound that leads to atherosclerosis and cardiovascular disease. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of aminoadipic acid are associated with at least two inborn errors of metabolism including 2-aminoadipic aciduria and 2-oxoadipic aciduria. Aminoadipic acid is an organic acid and abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart abnormalities, kidney abnormalities, liver damage, seizures, coma, and possibly death. These are also the characteristic symptoms of the untreated IEMs mentioned above. Many affected children with organic acidemias experience intellectual disability or delayed development. In adults, acidosis or acidemia is characterized by headaches, confusion, feeling tired, tremors, sleepiness, and seizures. As a diabetogen, serum aminoadipic levels appear to regulate glucose homeostasis and have been highly predictive of individuals who later develop diabetes (PMID: 24091325). In particular, aminoadipic acid lowers fasting plasma glucose levels and enhances insulin secretion from human islets. As an atherogen, aminoadipic acid has been found to be produced at high levels via protein lysine oxidation in atherosclerotic plaques (PMID: 28069522). A metabolite in the principal biochemical pathway of lysine. It antagonizes neuroexcitatory activity modulated by the glutamate receptor, N-methyl-D-aspartate; (NMDA). L-α-Aminoadipic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=1118-90-7 (retrieved 2024-07-01) (CAS RN: 1118-90-7). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Aminoadipic acid is an intermediate in the metabolism of lysine and saccharopine. Aminoadipic acid is an intermediate in the metabolism of lysine and saccharopine.

   

cis,cis-Muconic acid

(2Z,4Z)-HEXA-2,4-dienedioIC ACID

C6H6O4 (142.0266)


cis-cis-Muconic acid is a presumptive metabolite of benzene. Muconic acid was first isolated from the urine of rabbits and dogs in 1909 (M. Jaffe, Z Physiol Chem 62:58-67). It was originally thought that if muconic acid was formed by the opening of the benzene ring in vivo then the cis-cis isomer should be the initial (and primary) product. However subsequent studies conducted in the 1950s proved that trans-trans-muconic acid is a true metabolite of benzene in mammals (Parke DV, Williams RT. Biochem J 51:339-348 (1952)). Furthermore, dosing rabbits with phenol or catechol also resulted in the urinary excretion of trans-trans-muconic acid. The oxidative ring opening of benzene first gives rise to cis-cis-muconaldehyde, which then isomerizes to cis-trans- and trans-trans-muconaldehyde; the latter is oxidized in vivo to trans-trans-muconic acid. Isomerization of the trans-trans form may take place in vivo to yield small amounts if the cis-cis and cis-trans form of muconic acid. cis-cis-Muconic acid may also be generated from microbial fermentation of benzoic acid. Certain strains of arthobacter are particularly efficient at this process. cis-cis-Muconic acid can also be found in Pseudomonas and Escherichia coli (https://link.springer.com/article/10.1007/BF00250491) (PMID:26360870). Cis-cis-muconic acid is a presumptive metabolite of benzene. Muconic acid was first isolated from the urine of rabbits and dogs in 1909 ( M. Jaffe, Z Physiol Chem 62:58-67). It was originally thought that if muconic acid were formed by opening of the benzene ring in vivo then the cis-cis isomer should be the initial (and primary) product. However subsequent studies conducted in the 1950s proved that trans-trans-muconic acid is a true metabolite of benzene in mammals (Parke DV, Williams RT. Biochem J 51:339-348 (1952)). Furthermore, dosing rabbits with phenol or catechol also resulted in the urinary excretion of trans-trans-muconic acid. The oxidative ring opening of benzene first gives rise to cis-cis-muconaldehyde, which then isomerizes to cis-trans- and trans-trans-muconaldehyde; the latter is oxidized in vivo to trans-trans-muconic acid. Isomerization of the trans-trans form may take place in vivo to yield small amounts if the cis-cis and cis-trans form of muconic acid. Cis-cis muconic acid may also be generated from microbial fermentation of benzoic acid. Certain strains of arthobacter are particularly efficient at this process. [HMDB] KEIO_ID M105 cis,cis-Muconic acid, a metabolic intermediate of Klebsiella pneumonia, can be converted to adipic acid and terephthalic acid, which are important monomers of synthetic polymers. cis,cis-Muconic acid is also a biochemical material that can be used for the production of various plastics and polymers and is particularly gaining attention as an adipic acid precursor for the synthesis of nylon-6,6[1][2].

   

Aconitate [cis or trans]

(1Z)-prop-1-ene-1,2,3-tricarboxylic acid

C6H6O6 (174.0164)


cis-Aconitic acid is an intermediate in the tricarboxylic acid cycle produced by the dehydration of citric acid. The enzyme aconitase (aconitate hydratase; EC 4.2.1.3) catalyses the stereo-specific isomerization of citrate to isocitrate via cis-aconitate in the tricarboxylic acid cycle. Present in apple fruits, maple syrup and passion fruit juice cis-Aconitic acid, also known as (Z)-aconitic acid, plays several important biological roles: Intermediate in the Citric Acid Cycle: cis-Aconitic acid is an intermediate in the tricarboxylic acid (TCA) cycle, also known as the Krebs cycle or citric acid cycle. It is formed from citrate by the enzyme aconitase and is rapidly converted into isocitrate, another key intermediate in the cycle. The TCA cycle is central to cellular respiration, generating energy-rich molecules like NADH and FADH2. Regulation of Aconitase Activity: The conversion of citrate to cis-aconitate and then to isocitrate by aconitase is an important regulatory step in the TCA cycle. This conversion helps in maintaining the balance of the cycle and is influenced by factors like the energy status of the cell. Role in Cholesterol Synthesis: cis-Aconitic acid is also involved in the synthesis of cholesterol. It serves as a precursor for the synthesis of mevalonate, a key intermediate in the cholesterol biosynthesis pathway. Potential Involvement in Disease: Altered metabolism or accumulation of cis-aconitic acid has been associated with certain diseases, including neurodegenerative disorders and cancer. Its role in these conditions is an area of ongoing research. Plant Growth and Development: In plants, cis-aconitic acid has been found to play a role in growth and development, including seed germination and leaf senescence. In summary, cis-aconitic acid is a crucial intermediate in the TCA cycle, impacting energy production and various metabolic pathways in cells. Its role extends to cholesterol synthesis and potentially to various disease processes, highlighting its importance in cellular metabolism and physiology. cis-Aconitic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=585-84-2 (retrieved 2024-07-01) (CAS RN: 585-84-2). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). (Z)-Aconitic acid (cis-Aconitic acid) is the cis-isomer of Aconitic acid. (Z)-Aconitic acid (cis-Aconitic acid) is an intermediate in the tricarboxylic acid cycle produced by the dehydration of citric acid. (Z)-Aconitic acid (cis-Aconitic acid) is the cis-isomer of Aconitic acid. (Z)-Aconitic acid (cis-Aconitic acid) is an intermediate in the tricarboxylic acid cycle produced by the dehydration of citric acid.

   

Mesaconic acid

trans-1-Propene-1,2-dicarboxylic acid

C5H6O4 (130.0266)


Mesaconic acid, also known as 2-methylfumarate or citronic acid, belongs to the class of organic compounds known as methyl-branched fatty acids. These are fatty acids with an acyl chain that has a methyl branch. Usually, they are saturated and contain only one or more methyl group. However, branches other than methyl may be present. Mesaconic acid is a dicarboxylic butenoic acid, with a methyl group in position 2 and the double bound between carbons 2 and 3. Mesaconic acid was first studied for its physical properties in 1874 by Jacobus van ‘t Hoff (https://web.archive.org/web/20051117102410/http://dbhs.wvusd.k12.ca.us/webdocs/Chem-History/Van\\%27t-Hoff-1874.html). It is now known to be involved in the biosynthesis of vitamin B12 and it is also a competitor inhibitor of the reduction of fumarate. Mesaconic acid is one of several isomeric carboxylic acids obtained from citric acid. Is used as a fire retardant, recent studies revealed this acid is a competitive inhibitor of fumarate reduction. [HMDB] Acquisition and generation of the data is financially supported in part by CREST/JST. D003879 - Dermatologic Agents

   

Guanidinoacetate

2-[[Amino(imino)methyl]amino]acetic acid

C3H7N3O2 (117.0538)


Guanidoacetic acid (GAA), also known as guanidinoacetate or glycocyamine, belongs to the class of organic compounds known as alpha amino acids and derivatives. These are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon), or a derivative thereof. Guanidinoacetic acid was first prepared in 1861 by Adolph Strecker by reaction of cyanamide with glycine in aqueous solution. Manufactured guanidinoacetic acid is primarily used a feed additive approved by EFSA in poultry farming (for fattening), and pigs for fattening. Guanidoacetic acid exists naturally in all vertebrates. It is formed primarily in the kidneys by transferring the guanidine group of L-arginine to the amino acid glycine via the enzyme known as L-Arg:Gly-amidinotransferase (AGAT). In a further step, guanidinoacetate is methylated to generate creatine using S-adenosyl methionine (as the methyl donor) via the enzyme known as guanidinoacetate N-methyltransferase (GAMT). The resulting creatine is released into the bloodstream. Elevated levels of guanidoacetic acid are a characteristic of an inborn metabolic disorder known as Guanidinoacetate Methyltransferase (GAMT) Deficiency. GAMT converts guanidinoacetate to creatine and deficiency of this enzyme results in creatine depletion and accumulation of guanidinoacetate The disorder is transmitted in an autosomal recessive fashion and is localized to mutations on chromosome 19p13.3. GAMT deficiency is characterized by developmental arrest, medication-resistant epilepsy (myoclonic, generalized tonic-clonic, partial complex, atonic), severe speech impairment, progressive dystonia, dyskinesias, hypotonia, ataxia, and autistic-like behavior. Guanidino acetic acid, also known as guanidinoacetate or glycocyamine, belongs to alpha amino acids and derivatives class of compounds. Those are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon), or a derivative thereof. Guanidino acetic acid is slightly soluble (in water) and a weakly acidic compound (based on its pKa). Guanidino acetic acid can be found in apple and loquat, which makes guanidino acetic acid a potential biomarker for the consumption of these food products. Guanidino acetic acid can be found primarily in most biofluids, including cellular cytoplasm, feces, urine, and cerebrospinal fluid (CSF), as well as in human brain, kidney and liver tissues. In humans, guanidino acetic acid is involved in a couple of metabolic pathways, which include arginine and proline metabolism and glycine and serine metabolism. Guanidino acetic acid is also involved in several metabolic disorders, some of which include dihydropyrimidine dehydrogenase deficiency (DHPD), hyperprolinemia type II, prolinemia type II, and hyperornithinemia-hyperammonemia-homocitrullinuria [hhh-syndrome]. Moreover, guanidino acetic acid is found to be associated with chronic renal failure and schizophrenia. Guanidino acetic acid is a non-carcinogenic (not listed by IARC) potentially toxic compound. Chronic Exposure: Kidney dialysis is usually needed to relieve the symptoms of uremic syndrome until normal kidney function can be restored. D019995 - Laboratory Chemicals > D007202 - Indicators and Reagents > D000345 - Affinity Labels Acquisition and generation of the data is financially supported in part by CREST/JST.

   

Pipecolic acid

Pipecolic acid, 14C-labeled CPD, (+,-)-isomer

C6H11NO2 (129.079)


Pipecolic acid is a metabolite of lysine found in human physiological fluids such as urine, plasma and CSF. However, it is uncertain if pipecolic acid originates directly from food intake or from mammalian or intestinal bacterial enzyme metabolism. Recent studies suggest that plasma pipecolic acid, particularly the D-isomer, originates mainly from the catabolism of dietary lysine by intestinal bacteria rather than by direct food intake. In classic Zellweger syndrome (a cerebro-hepato-renal genetic disorder, OMIM 214100) pipecolic acid accumulate in the plasma of the patients. It is known that plasma pipecolic acid levels are also elevated in patients with chronic liver diseases. Pipecolic acid is moderately elevated in patients with pyridoxine-dependent seizures and might therefore be a possible biochemical marker for selecting candidates for pyridoxine therapy (Plecko et al 2000). Pipecolic acid was also elevated in CSF in these vitamin B6-responsive patients (PMID 12705501). Pipecolic acid is found to be associated with adrenoleukodystrophy, infantile Refsum disease, and peroxisomal biogenesis defect, which are also inborn errors of metabolism. Pipecolic acid is a biomarker for the consumption of dried and cooked beans. Pipecolic acid is a metabolite of lysine found in human physiological fluids such as urine, plasma and CSF. However, it is uncertain if pipecolic acid originates directly from food intake or from mammalian or intestinal bacterial enzyme metabolism. Recent studies suggest that plasma pipecolic acid, particularly the D-isomer, originates mainly from the catabolism of dietary lysine by intestinal bacteria rather than by direct food intake. In classic Zellweger syndrome (a cerebro-hepato-renal genetic disorder, OMIM 214100) pipecolic acid accumulate in the plasma of the patients. It is known that plasma pipecolic acid levels are also elevated in patients with chronic liver diseases. Pipecolic acid is moderately elevated in patients with pyridoxine-dependent seizures and might therefore be a possible biochemical marker for selecting candidates for pyridoxine therapy (Plecko et al 2000). Pipecolic acid was also elevated in CSF in these vitamin B6-responsive patients. (PMID 12705501) [HMDB]. Pipecolic acid is a biomarker for the consumption of dried and cooked beans. Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID P048 L-Pipecolic acid (H-HoPro-OH) is a breakdown product of lysine, accumulates in body fluids of infants with generalized genetic peroxisomal disorders, such as Zellweger syndrome, neonatal adrenoleukodystrophy. L-Pipecolic acid (H-HoPro-OH) is a breakdown product of lysine, accumulates in body fluids of infants with generalized genetic peroxisomal disorders, such as Zellweger syndrome, neonatal adrenoleukodystrophy. Pipecolic acid, a metabolite of Lysine, is an important precursor of many useful microbial secondary metabolites. Pipecolic acid can be used as a diagnostic marker of Pyridoxine-dependent epilepsy[1][2]. Pipecolic acid, a metabolite of Lysine, is an important precursor of many useful microbial secondary metabolites. Pipecolic acid can be used as a diagnostic marker of Pyridoxine-dependent epilepsy[1][2].

   

Pyrrole-2-carboxylic acid

1H-Pyrrole-2-carboxylic acid

C5H5NO2 (111.032)


Pyrrole-2-carboxylic acid was synthesized over a century ago, but its history as a compound of biological origin is rather recent. It was first identified as a degradation product of sialic acids, then as a derivative of the oxidation of the D-hydroxyproline isomers by mammalian D-amino acid oxidase. The latter relationship results from the lability of the direct oxidation product, A-pyrroline-4-hydroxy-2-carboxylic acid, which loses water spontaneously to form the pyrrole. A similar reaction is catalyzed by the more specific allohydroxy-D-proline oxidase of Pseudomonas. In whole animal observations, pyrrole-2-carboxylate (PCA) was identified in rat or human urine after administration of the D-isomers of hydroxyproline, a finding ascribable to the action of D-amino acid oxidase. (PMID:4430715). Urinary excretion of N-(pyrrole-2-carboxyl) glycine has been reported in a 5-year-old affected with type II hyperprolinemia; The child has mild developmental delay, recurrent seizures of the grand mal type and EEG alterations. The urinary excretion of the conjugate is stressed, since it appears that only one previous report in the literature described this compound in the urine of two patients affected by this disturbance (PMID 2383933). Pyrrole-2-carboxylic acid was synthesized over a century ago, but its history as a compound of biological origin is rather recent. It was first identified as a degradation product of sialic acids, then as a derivative of the oxidation of the D-hydroxyproline isomers by mammalian D-amino acid oxidase. The latter relationship results from the lability of the direct oxidation product, A-pyrroline-4-hydroxy-2-carboxylic acid, which loses water spontaneously to form the pyrrole. A similar reaction is catalyzed by the more specific allohydroxy-D-proline oxidase of Pseudomonas. In whole animal observations, pyrrole-2-carboxylate (PCA) was identified in rat or human urine after administration of the D-isomers of hydroxyproline, a finding ascribable to the action of D-amino acid oxidase. (PMID: 4430715) KEIO_ID P112 Pyrrole-2-carboxylic acid is a natural alkaloid from the marine bacterium Pelomonas puraquae sp. Nov. Pyrrole-2-carboxylic acid is a natural alkaloid from the marine bacterium Pelomonas puraquae sp. Nov.

   

Baclofen

beta-(Aminomethyl)-4-chlorobenzenepropanoic acid

C10H12ClNO2 (213.0557)


Baclofen is a gamma-amino-butyric acid (GABA) derivative used as a skeletal muscle relaxant. Baclofen stimulates GABA-B receptors leading to decreased frequency and amplitude of muscle spasms. It is especially useful in treating muscle spasticity associated with spinal cord injury. It appears to act primarily at the spinal cord level by inhibiting spinal polysynaptic afferent pathways and, to a lesser extent, monosynaptic afferent pathways. M - Musculo-skeletal system > M03 - Muscle relaxants > M03B - Muscle relaxants, centrally acting agents D018377 - Neurotransmitter Agents > D018682 - GABA Agents > D018755 - GABA Agonists D018373 - Peripheral Nervous System Agents > D009465 - Neuromuscular Agents C78281 - Agent Affecting Musculoskeletal System > C29696 - Muscle Relaxant D002491 - Central Nervous System Agents (R)-Baclofen (Arbaclofen) is a selective GABAB receptor agonist[1]. Baclofen, a lipophilic derivative of γ-aminobutyric acid (GABA), is an orally active, selective metabotropic GABAB receptor (GABABR) agonist. Baclofen mimics the action of GABA and produces slow presynaptic inhibition through the GABAB receptor. Baclofen has high blood brain barrier penetrance. Baclofen has the potential for muscle spasticity research[1][2][3].

   

Adipic acid

1,4-Butanedicarboxylic acid

C6H10O4 (146.0579)


Adipic acid is an important inudstrial dicarboxylic acid with about 2.5 billion kilograms produced per year. It is used mainly in the production of nylon. It occurs relatively rarely in nature. It has a tart taste and is also used as an additive and gelling agent in jello or gelatins. It is also used in some calcium carbonate antacids to make them tart. Adipic acid has also been incorporated into controlled-release formulation matrix tablets to obtain pH-independent release for both weakly basic and weakly acidic drugs. Adipic acid in the urine and in the blood is typically exogenous in origin and is a good biomarker of jello consumption. In fact, a condition known as adipic aciduria is actually an artifact of jello consumption (PMID: 1779643). However, certain disorders (such as diabetes and glutaric aciduria type I.) can lead to elevated levels of adipic acid snd other dicarboxcylic acids (such as suberic acid) in urine (PMID: 17520433; PMID: 6778884). Moreover, adipic acid is also found to be associated with 3-hydroxy-3-methylglutaryl-CoA lyase deficiency, carnitine-acylcarnitine translocase deficiency, malonyl-Coa decarboxylase deficiency, and medium Chain acyl-CoA dehydrogenase deficiency, which are inborn errors of metabolism. Adipic acid is also microbial metabolite found in Escherichia. Constituent of beet juice, pork fat, guava fruit (Psidium guajava), papaya (Carica papaya) and raspberry (Rubus idaeus). Food acidulant Adipic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=124-04-9 (retrieved 2024-07-16) (CAS RN: 124-04-9). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Adipic acid is found to be associated with HMG-CoA lyase deficiency, carnitine-acylcarnitine translocase deficiency, malonyl-Coa decarboxylase deficiency, and medium Chain acyl-CoA dehydrogenase deficiency, which are inborn errors of metabolism.

   

Diaminopimelic acid

( (R*,s*)-2,6-diamino-heptanedioic acid

C7H14N2O4 (190.0954)


Diaminopimelic acid or DAPA is a lysine-like amino acid derivative that is a key component of the bacterial cell wall. DAPA is incorporated or integrated into peptidoglycan of gram negative bacteria and is the attachment point for Brauns lipoprotein (BLP or Murein Lipoprotein). BLP is found in gram-negative cell walls and is one of the most abundant membrane proteins. BLP is bound at its C-terminal end (a lysine) by a covalent bond to the peptidoglycan layer (specifically to diaminopimelic acid molecules) and is embedded in the outer membrane by its hydrophobic head (a cysteine with lipids attached). BLP tightly links the two layers and provides structural integrity to the bacterial outer membrane. Diaminopimelic acid can be found in human urine or feces due to the lysis or enzymatic breakdown of gram negative gut microbes. Acquisition and generation of the data is financially supported in part by CREST/JST. 2,6-Diaminoheptanedioic acid is an endogenous metabolite.

   

Glutaric acid

1,3-Propanedicarboxylic acid

C5H8O4 (132.0423)


Glutaric acid is a simple five-carbon linear dicarboxylic acid. Glutaric acid is naturally produced in the body during the metabolism of some amino acids, including lysine and tryptophan. Glutaric acid may cause irritation to the skin and eyes. When present in sufficiently high levels, glutaric acid can act as an acidogen and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of glutaric acid are associated with at least three inborn errors of metabolism, including glutaric aciduria type I, malonyl-CoA decarboxylase deficiency, and glutaric aciduria type III. Glutaric aciduria type I (glutaric acidemia type I, glutaryl-CoA dehydrogenase deficiency, GA1, or GAT1) is an inherited disorder in which the body is unable to completely break down the amino acids lysine, hydroxylysine, and tryptophan due to a deficiency of mitochondrial glutaryl-CoA dehydrogenase (EC 1.3.99.7, GCDH). Excessive levels of their intermediate breakdown products (e.g. glutaric acid, glutaryl-CoA, 3-hydroxyglutaric acid, glutaconic acid) can accumulate and cause damage to the brain (and also other organs). Babies with glutaric acidemia type I are often born with unusually large heads (macrocephaly). Macrocephaly is amongst the earliest signs of GA1. GA1 also causes secondary carnitine deficiency because glutaric acid, like other organic acids, is detoxified by carnitine. Abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart, liver, and kidney abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of untreated glutaric aciduria. Many affected children with organic acidemias experience intellectual disability or delayed development. In adults, acidosis or acidemia is characterized by headaches, confusion, feeling tired, tremors, sleepiness, and seizures. Treatment of glutaric aciduria is mainly based on the restriction of lysine intake, supplementation of carnitine, and an intensification of therapy during intercurrent illnesses. The major principle of dietary treatment is to reduce the production of glutaric acid and 3-hydroxyglutaric acid by restriction of natural protein, in general, and of lysine, in particular (PMID: 17465389, 15505398). Glutaric acid has also been found in Escherichia (PMID: 30143200). Isolated from basidiomycete fungi and fruits of Prunus cerasus (CCD). Glutaric acid is found in many foods, some of which are red beetroot, common beet, soy bean, and tamarind. Glutaric acid, C5 dicarboxylic acid, is an intermediate during the catabolic pathways of lysine and tryptophan. Glutaric acid affects pericyte contractility and migration. Glutaric acid is an indicator of glutaric aciduria type I[1][2][3]. Glutaric acid, C5 dicarboxylic acid, is an intermediate during the catabolic pathways of lysine and tryptophan. Glutaric acid affects pericyte contractility and migration. Glutaric acid is an indicator of glutaric aciduria type I[1][2][3].

   

Palmitoleic acid

cis-Delta(9)-Hexadecenoic acid

C16H30O2 (254.2246)


Cis-9-palmitoleic acid, also known as palmitoleate or (Z)-9-hexadecenoic acid, is a member of the class of compounds known as long-chain fatty acids. Long-chain fatty acids are fatty acids with an aliphatic tail that contains between 13 and 21 carbon atoms. Thus, cis-9-palmitoleic acid is considered to be a fatty acid lipid molecule. Cis-9-palmitoleic acid is practically insoluble (in water) and a weakly acidic compound (based on its pKa). Cis-9-palmitoleic acid can be found in a number of food items such as mixed nuts, carrot, hedge mustard, and chanterelle, which makes cis-9-palmitoleic acid a potential biomarker for the consumption of these food products. Cis-9-palmitoleic acid can be found primarily in most biofluids, including urine, blood, saliva, and feces, as well as in human adipose tissue, prostate and skeletal muscle tissues. Cis-9-palmitoleic acid exists in all living species, ranging from bacteria to humans. Moreover, cis-9-palmitoleic acid is found to be associated with isovaleric acidemia. Palmitoleic acid, or (9Z)-hexadec-9-enoic acid, is an omega-7 monounsaturated fatty acid (16:1n-7) with the formula CH3(CH2)5CH=CH(CH2)7COOH that is a common constituent of the glycerides of human adipose tissue. Present in all tissues, it is generally found in higher concentrations in the liver. Macadamia oil (Macadamia integrifolia) and sea buckthorn oil (Hippophae rhamnoides) are botanical sources of palmitoleic acid, containing 22 and 40\\\\\% respectively. Palmitoleic acid is found to be associated with isovaleric acidemia, which is an inborn error of metabolism. Palmitoleic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=373-49-9 (retrieved 2024-07-15) (CAS RN: 373-49-9). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Palmitoleic acid, a composition of fatty acid, is implicated in the prevention of death from cerebrovascular disorders in SHRSP rats. Palmitoleic acid, a composition of fatty acid, is implicated in the prevention of death from cerebrovascular disorders in SHRSP rats.

   

Pimelic acid

1,5-Pentanedicarboxylic acid

C7H12O4 (160.0736)


Pimelic acid, also known as heptanedioic acid is a dicarboxylic acid. Derivatives of pimelic acid are involved in the biosynthesis of the amino acid called lysine. Pimelic acid is one methylene longer than a related dicarboxylic acid, adipic acid, a precursor to many polyesters and polyamides. Pimelic acid is essential for the synthesis of biotin (also called vitamin B7). Biotin is a heterocyclic, S-containing monocarboxylic acid that is made from two precursors, alanine and pimeloyl-CoA. Biotin is important in fatty acid synthesis, branched-chain amino acid catabolism, and gluconeogenesis. Biotin is found in a wide range of foods. Likewise, intestinal bacteria synthesize biotin, which is then absorbed by the host animal. Pimelic acid (which is the precursor for pimeloyl-CoA) is synthesized in many bacteria via a head-to-tail incorporation of acetate units through a modified fatty acid synthetic pathway using O-methyl esters disguised to resemble the canonical intermediates of the fatty acid synthetic pathway (PMID:21435937). Some bacteria and yeast synthesize pimelic acid not by biosynthesis, but via cleavage of longer chain fatty acids (such as linolenic acid) via a cytochrome P450-like enzyme (PMID:28196402, 21435937, 3236079). Pimelic acid is excreted in elevated amounts in the urine of individuals with mitochondrial beta-oxidation disorders and peroxisomal beta oxidation disorders (PMID:1527989) A group of compounds that are derivatives of heptanedioic acid with the general formula R-C7H11O4. KEIO_ID P063 Pimelic acid is the organic compound and its derivatives are involved in the biosynthesis of the amino acid called lysine. Pimelic acid is the organic compound and its derivatives are involved in the biosynthesis of the amino acid called lysine.

   

Phosphoenolpyruvic acid

Phosphoenolpyruvic Acid Trisodium Salt monohydrate

C3H5O6P (167.9824)


Phosphoenolpyruvate, also known as pep or 2-(phosphonooxy)-2-propenoic acid, is a member of the class of compounds known as phosphate esters. Phosphate esters are organic compounds containing phosphoric acid ester functional group, with the general structure R1P(=O)(R2)OR3. R1,R2 = O,N, or halogen atom; R3 = organyl group. Phosphoenolpyruvate is soluble (in water) and an extremely strong acidic compound (based on its pKa). Phosphoenolpyruvate can be found in a number of food items such as okra, endive, chestnut, and dandelion, which makes phosphoenolpyruvate a potential biomarker for the consumption of these food products. Phosphoenolpyruvate can be found primarily in blood, cellular cytoplasm, and saliva, as well as in human prostate tissue. Phosphoenolpyruvate exists in all living species, ranging from bacteria to humans. In humans, phosphoenolpyruvate is involved in several metabolic pathways, some of which include glycolysis, amino sugar metabolism, gluconeogenesis, and glycogenosis, type IC. Phosphoenolpyruvate is also involved in several metabolic disorders, some of which include glycogen storage disease type 1A (GSD1A) or von gierke disease, salla disease/infantile sialic acid storage disease, phosphoenolpyruvate carboxykinase deficiency 1 (PEPCK1), and pyruvate dehydrogenase complex deficiency. Phosphoenolpyruvate (2-phosphoenolpyruvate, PEP) as the ester derived from the enol of pyruvate and phosphate. It exists as an anion; the parent acid, which is only of theoretical interest, is phosphoenolpyruvic acid. PEP is an important intermediate in biochemistry. It has the highest-energy phosphate bond found (−61.9 kJ/mol) in living organisms, and is involved in glycolysis and gluconeogenesis. In plants, it is also involved in the biosynthesis of various aromatic compounds, and in carbon fixation; in bacteria, it is also used as the source of energy for the phosphotransferase system . Phosphoenolpyruvate (PEP) is an important chemical compound in biochemistry. It has a high energy phosphate bond, and is involved in glycolysis and gluconeogenesis. In glycolysis, PEP is formed by the action of the enzyme enolase on 2-phosphoglycerate. Metabolism of PEP to pyruvate by pyruvate kinase (PK) generates 1 molecule of adenosine triphosphate (ATP) via substrate-level phosphorylation. ATP is one of the major currencies of chemical energy within cells. In gluconeogenesis, PEP is formed from the decarboxylation of oxaloacetate and hydrolysis of 1 guanosine triphosphate molecule. This reaction is catalyzed by the enzyme phosphoenolpyruvate carboxykinase (PEPCK). This reaction is a rate-limiting step in gluconeogenesis. (wikipedia). [Spectral] Phosphoenolpyruvate (exact mass = 167.98237) and 6-Phospho-D-gluconate (exact mass = 276.02463) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID P007

   

Itaconic acid

2-Hydroxy-3-naphthoyl-2-naphthylamine

C5H6O4 (130.0266)


Itaconic acid is a dicarboxylic acid that is methacrylic acid in which one of the methyl hydrogens is substituted by a carboxylic acid group. It has a role as a fungal metabolite and a human metabolite. It is a dicarboxylic acid and an olefinic compound. It derives from a succinic acid. It is a conjugate acid of an itaconate(2-). This dicarboxylic acid is a white solid that is soluble in water, ethanol, and acetone. Historically, itaconic acid was obtained by the distillation of citric acid, but currently it is produced by fermentation. The name itaconic acid was devised as an anagram of aconitic acid, another derivative of citric acid. Itaconic acid, also known as itaconate, belongs to the class of organic compounds known as branched fatty acids. These are fatty acids containing a branched chain. Itaconic acid is a very hydrophobic molecule, practically insoluble in water, and relatively neutral. Since the 1960s, it is produced industrially by the fermentation of carbohydrates such as glucose or molasses using fungi such as Aspergillus itaconicus or Aspergillus terreus. For A. terreus the itaconate pathway is mostly elucidated. The generally accepted route for itaconate is via glycolysis, tricarboxylic acid cycle, and a decarboxylation of cis-aconitate to itaconate via cis-aconitate-decarboxylase. The smut fungus Ustilago maydis uses an alternative route. Cis-aconitate is converted to the thermodynamically favoured trans-aconitate via aconitate-Δ-isomerase (Adi1). trans-Aconitate is further decarboxylated to itaconate by trans-aconitate-decarboxylase (Tad1). Itaconic acid is also produced in cells of macrophage lineage. It was shown that itaconate is a covalent inhibitor of the enzyme isocitrate lyase in vitro. As such, itaconate may possess antibacterial activities against bacteria expressing isocitrate lyase (such as Salmonella enterica and Mycobacterium tuberculosis). It is also sythesized in the laboratory, where dry distillation of citric acid affords itaconic anhydride, which undergoes hydrolysis to itaconic acid. Itaconic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=97-65-4 (retrieved 2024-07-01) (CAS RN: 97-65-4). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Itaconic acid, a precursor of polymers, chemicals, and fuels, can be synthesized by many fungi. Itaconic acid also is a macrophage-specific metabolite. Itaconic acid mediates crosstalk between macrophage metabolism and peritoneal tumors[1][2].

   

DL-Malic acid

2-Hydroxyethane-1,2-dicarboxylic acid

C4H6O5 (134.0215)


Malic acid (CAS: 6915-15-7) is a tart-tasting organic dicarboxylic acid that plays a role in many sour or tart foods. Apples contain malic acid, which contributes to the sourness of a green apple. Malic acid can make a wine taste tart, although the amount decreases with increasing fruit ripeness (Wikipedia). In its ionized form, malic acid is called malate. Malate is an intermediate of the TCA cycle along with fumarate. It can also be formed from pyruvate as one of the anaplerotic reactions. In humans, malic acid is both derived from food sources and synthesized in the body through the citric acid cycle or Krebs cycle which takes place in the mitochondria. Malates importance to the production of energy in the body during both aerobic and anaerobic conditions is well established. Under aerobic conditions, the oxidation of malate to oxaloacetate provides reducing equivalents to the mitochondria through the malate-aspartate redox shuttle. During anaerobic conditions, where a buildup of excess reducing equivalents inhibits glycolysis, malic acids simultaneous reduction to succinate and oxidation to oxaloacetate is capable of removing the accumulating reducing equivalents. This allows malic acid to reverse hypoxias inhibition of glycolysis and energy production. In studies on rats, it has been found that only tissue malate is depleted following exhaustive physical activity. Other key metabolites from the citric acid cycle needed for energy production were found to be unchanged. Because of this, a deficiency of malic acid has been hypothesized to be a major cause of physical exhaustion. Notably, the administration of malic acid to rats has been shown to elevate mitochondrial malate and increase mitochondrial respiration and energy production. Malic acid has been found to be a metabolite in Aspergillus (Hugo Vanden Bossche, D.W.R. Mackenzie and G. Cauwenbergh. Aspergillus and Aspergillosis, 1987). Acidulant, antioxidant, flavouring agent, flavour enhancer. Not for use in baby foods (GRAS) Malic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=617-48-1 (retrieved 2024-07-01) (CAS RN: 6915-15-7). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). (S)-Malic acid ((S)-2-Hydroxysuccinic acid) is a dicarboxylic acid in naturally occurring form, contributes to the pleasantly sour taste of fruits and is used as a food additive. (S)-Malic acid ((S)-2-Hydroxysuccinic acid) is a dicarboxylic acid in naturally occurring form, contributes to the pleasantly sour taste of fruits and is used as a food additive. Malic acid (Hydroxybutanedioic acid) is a dicarboxylic acid that is naturally found in fruits such as apples and pears. It plays a role in many sour or tart foods. Malic acid (Hydroxybutanedioic acid) is a dicarboxylic acid that is naturally found in fruits such as apples and pears. It plays a role in many sour or tart foods.

   

Threonic acid

2,3,4-Trihydroxy-(threo)-butanoic acid

C4H8O5 (136.0372)


Threonic acid, also known as threonate, belongs to the class of organic compounds known as sugar acids and derivatives. Sugar acids and derivatives are compounds containing a saccharide unit which bears a carboxylic acid group. Threonic acid is a sugar acid derived from threose. The L-isomer is a metabolite of ascorbic acid (vitamin C). One study suggested that because L-threonate inhibits DKK1 expression in vitro, it may have potential in the treatment of androgenic alopecia (PMID:21034532). Threonic acid is probably derived from glycated proteins or from degradation of ascorbic acid. It is a normal component in aqueous humour and blood (PMID:10420182). Threonic acid is a substrate of L-threonate 3-dehydrogenase (EC 1.1.1.129) in the ascorbate and aldarate metabolism pathway (KEGG). It has been found to be a microbial metabolite (PMID:20615997). L-threonic acid, also known as L-threonate or L-threonic acid magnesium salt, belongs to sugar acids and derivatives class of compounds. Those are compounds containing a saccharide unit which bears a carboxylic acid group. L-threonic acid is soluble (in water) and a weakly acidic compound (based on its pKa). L-threonic acid can be found in a number of food items such as buffalo currant, yam, purslane, and bayberry, which makes L-threonic acid a potential biomarker for the consumption of these food products. L-threonic acid can be found primarily in blood. Threonic acid is a sugar acid derived from threose. The L-isomer is a metabolite of ascorbic acid (vitamin C). One study suggested that because L-threonate inhibits DKK1 expression in vitro, it may have potential in treatment of androgenic alopecia .

   

Methylmalonic acid

1,1-Ethanedicarboxylic acid

C4H6O4 (118.0266)


Methylmalonic acid is a malonic acid derivative, which is a vital intermediate in the metabolism of fat and protein. In particular, the coenzyme A-linked form of methylmalonic acid, methylmalonyl-CoA, is converted into succinyl-CoA by methylmalonyl-CoA mutase in a reaction that requires vitamin B12 as a cofactor. In this way, methylmalonic acid enters the Krebs cycle and is thus part of one of the anaplerotic reactions. Abnormalities in methylmalonic acid metabolism lead to methylmalonic aciduria. This inborn error of metabolism is attributed to a block in the enzymatic conversion of methylmalonyl CoA to succinyl CoA. Methylmalonic acid is also found to be associated with other inborn errors of metabolism, including cobalamin deficiency, cobalamin malabsorption, malonyl-CoA decarboxylase deficiency, and transcobalamin II deficiency. When present in sufficiently high levels, methylmalonic acid can act as an acidogen and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of methylmalonic acid are associated with at least 5 inborn errors of metabolism, including Malonyl CoA decarboxylase deficiency, Malonic Aciduria, Methylmalonate Semialdehyde Dehydrogenase Deficiency, Methylmalonic Aciduria and Methylmalonic Aciduria Due to Cobalamin-Related Disorders. Methylmalonic acid is an organic acid and abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart abnormalities, kidney abnormalities, liver damage, seizures, coma, and possibly death. These are also the characteristic symptoms of the untreated IEMs mentioned above. Many affected children with organic acidemias experience intellectual disability or delayed development. In adults, acidosis or acidemia is characterized by headaches, confusion, feeling tired, tremors, sleepiness, and seizures. A malonic acid derivative which is a vital intermediate in the metabolism of fat and protein. Abnormalities in methylmalonic acid metabolism lead to methylmalonic aciduria. This metabolic disease is attributed to a block in the enzymatic conversion of methylmalonyl CoA to succinyl CoA. [HMDB] KEIO_ID M014 Methylmalonic acid (Methylmalonate) is an indicator of Vitamin B-12 deficiency in cancer. Methylmalonic acid (Methylmalonate) is an indicator of Vitamin B-12 deficiency in cancer.

   

Oxaloacetate

2-oxobutanedioic acid

C4H4O5 (132.0059)


Oxalacetic acid, also known as oxaloacetic acid, keto-oxaloacetate or 2-oxobutanedioate, belongs to the class of organic compounds known as short-chain keto acids and derivatives. These are keto acids with an alkyl chain the contains less than 6 carbon atoms. Oxalacetic acid is a metabolic intermediate in many processes that occur in animals and plants. It takes part in gluconeogenesis, the urea cycle, the glyoxylate cycle, amino acid synthesis, fatty acid synthesis and the citric acid cycle. Oxalacetic acid exists in all living species, ranging from bacteria to plants to humans. Within humans, oxalacetic acid participates in a number of enzymatic reactions. In particular, oxalacetic acid is an intermediate of the citric acid cycle, where it reacts with acetyl-CoA to form citrate, catalyzed by citrate synthase. It is also involved in gluconeogenesis and the urea cycle. In gluconeogenesis oxaloacetate is decarboxylated and phosphorylated by phosphoenolpyruvate carboxykinase and becomes 2-phosphoenolpyruvate using guanosine triphosphate (GTP) as phosphate source. In the urea cycle, malate is acted on by malate dehydrogenase to become oxaloacetate, producing a molecule of NADH. After that, oxaloacetate can be recycled to aspartate, as this recycling maintains the flow of nitrogen into the cell. In mice, injections of oxalacetic acid have been shown to promote brain mitochondrial biogenesis, activate the insulin signaling pathway, reduce neuroinflammation and activate hippocampal neurogenesis (PMID: 25027327). Oxalacetic acid has also been reported to reduce hyperglycemia in type II diabetes and to extend longevity in C. elegans (PMID: 25027327). Outside of the human body, oxalacetic acid has been detected, but not quantified in, several different foods, such as Persian limes, lemon balms, wild rice, canola, and peanuts. This could make oxalacetic acid a potential biomarker for the consumption of these foods. Oxalacetic acid, also known as ketosuccinic acid or oxaloacetate, belongs to short-chain keto acids and derivatives class of compounds. Those are keto acids with an alkyl chain the contains less than 6 carbon atoms. Thus, oxalacetic acid is considered to be a fatty acid lipid molecule. Oxalacetic acid is soluble (in water) and a moderately acidic compound (based on its pKa). Oxalacetic acid can be synthesized from succinic acid. Oxalacetic acid can also be synthesized into oxaloacetic acid 4-methyl ester. Oxalacetic acid can be found in a number of food items such as daikon radish, sacred lotus, cucurbita (gourd), and tarragon, which makes oxalacetic acid a potential biomarker for the consumption of these food products. Oxalacetic acid can be found primarily in cellular cytoplasm, cerebrospinal fluid (CSF), and urine, as well as in human liver tissue. Oxalacetic acid exists in all living species, ranging from bacteria to humans. In humans, oxalacetic acid is involved in several metabolic pathways, some of which include the oncogenic action of succinate, the oncogenic action of 2-hydroxyglutarate, glycogenosis, type IB, and the oncogenic action of fumarate. Oxalacetic acid is also involved in several metabolic disorders, some of which include the oncogenic action of l-2-hydroxyglutarate in hydroxygluaricaciduria, transfer of acetyl groups into mitochondria, argininemia, and 2-ketoglutarate dehydrogenase complex deficiency. Moreover, oxalacetic acid is found to be associated with anoxia. C274 - Antineoplastic Agent > C177430 - Agent Targeting Cancer Metabolism C26170 - Protective Agent > C1509 - Neuroprotective Agent Oxaloacetic acid (2-Oxosuccinic acid) is a metabolic intermediate involved in several ways, such as citric acid cycle, gluconeogenesis, the urea cycle, the glyoxylate cycle, amino acid synthesis, and fatty acid synthesis[1][2]. Oxaloacetic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=328-42-7 (retrieved 2024-10-17) (CAS RN: 328-42-7). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).

   

Suberic acid

octanedioic acid

C8H14O4 (174.0892)


Suberic acid, also octanedioic acid, is a dicarboxylic acid, with formula C6H12(COOH)2. It is present in the urine of patients with fatty acid oxidation disorders (PMID 10404733). A metabolic breakdown product derived from oleic acid. Elevated levels of this unstaruated dicarboxylic acid are found in individuals with medium-chain acyl-CoA dehydrogenase deficiency (MCAD). Suberic acid is also found to be associated with carnitine-acylcarnitine translocase deficiency, malonyl-Coa decarboxylase deficiency, which are also inborn errors of metabolism. Isolated from the roots of Phaseolus vulgaris (kidney bean) CONFIDENCE standard compound; INTERNAL_ID 153 KEIO_ID S013 Suberic acid (Octanedioic acid) is found to be associated with carnitine-acylcarnitine translocase deficiency, malonyl-Coa decarboxylase deficiency. Suberic acid (Octanedioic acid) is found to be associated with carnitine-acylcarnitine translocase deficiency, malonyl-Coa decarboxylase deficiency.

   

Glutaconic acid

1-Propene-1,3-dicarboxylic acid

C5H6O4 (130.0266)


Glutaconic acid is related to the fully saturated glutaric acid and belongs to the class of compounds known as dicarboxylic acids and derivatives. These are organic compounds containing exactly two carboxylic acid groups. Glutaconic acid is soluble (in water) and a weakly acidic compound (based on its pKa). Glutaconic acid has been detected in the urine of individuals with inborn errors of metabolism. When present in sufficiently high levels, glutaconic acid can act as an acidogen, a neurotoxin, and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A neurotoxin is a compound that is toxic to neural tissues and cells. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of glutaconic acid are associated with glutaric aciduria type I (glutaric acidemia type I, glutaryl-CoA dehydrogenase deficiency, GA1, or GAT1). GA1 is an inherited disorder in which the body is unable to completely break down the amino acids lysine, hydroxylysine, and tryptophan due to a deficiency of mitochondrial glutaryl-CoA dehydrogenase (EC 1.3.99.7, GCDH). Excessive levels of their intermediate breakdown products (e.g. glutaric acid, glutaryl-CoA, 3-hydroxyglutaric acid, glutaconic acid) can accumulate and cause damage to the brain (and also other organs), but particularly the basal ganglia. GA1 is associated with a risk for intracranial and retinal hemorrhage, and non-specific white matter changes. Babies with glutaric acidemia type I are often born with unusually large heads (macrocephaly). Other symptoms include spasticity (increased muscle tone/stiffness) and dystonia (involuntary muscle contractions resulting in abnormal movement or posture), but many affected individuals are asymptomatic. Seizures and coma (encephalopathy) are rare. GA1 also causes secondary carnitine deficiency because 3-hydroxyglutaric acid, like other organic acids, is detoxified by carnitine. Glutaconic acids neurotoxicity is thought to be partially caused by an excitotoxic mechanism in which glutaconic acid overactivates N-methyl-D-aspartate (NMDA) receptors. Accumulating trans-glutaconic (TG) acids have been proposed to be involved in the development of the striatal degeneration seen in children with glutaric acidemia type I via an excitotoxic mechanism. Glutaconic acid is an organic compound with general formula C5H6O4. The compound is a dicarboxylic acid and related with the fully saturated glutaric acid. [HMDB]

   

16-Hydroxyhexadecanoic acid

16-hydroxyhexadecanoic acid

C16H32O3 (272.2351)


16-Hydroxyhexadecanoic acid, also known as 16-hydroxypalmitic acid, is a hydroxylated fatty acid where the terminal (omega) carbon has been hydroxylated. In animal tissues, a family of enzymes termed cytochromes P450s are involved in fatty acid oxidation, hydroxylating with high specificity at the energetically unfavourable terminal (omega) or omega-1 carbons. Hydroxy fatty acids primarily come from the consumption of plant products (vegetables or fruits) or cow’s milk. Omega hydroxy fatty acids are found in the structure of suberin, a lipid polyester present in plant cell walls, and of cutin, a lipid polyester which is a component of the plant cuticle. These apoplastic structures are important plant-environment interfaces that act as barriers limiting water and nutrient loss and protecting plants from radiation and pathogens. 16-Hydroxyhexadecanoic acid and 18-hydroxystearic acid are particularly abundant in cutin in the plant cuticle. 16-Hydroxyhexadecanoic acid has been proposed as a biomarker of beer consumption. 16-hydroxy-hexadecanoic acid, also known as 16-hydroxypalmitic acid or 16-oh 16:0, is a member of the class of compounds known as long-chain fatty acids. Long-chain fatty acids are fatty acids with an aliphatic tail that contains between 13 and 21 carbon atoms. Thus, 16-hydroxy-hexadecanoic acid is considered to be a fatty acid lipid molecule. 16-hydroxy-hexadecanoic acid is practically insoluble (in water) and a weakly acidic compound (based on its pKa). 16-hydroxy-hexadecanoic acid can be synthesized from hexadecanoic acid. 16-hydroxy-hexadecanoic acid is also a parent compound for other transformation products, including but not limited to, (3R)-3,16-dihydroxypalmitic acid, oscr#28, and 16-hydroxyhexadecanoyl-CoA. 16-hydroxy-hexadecanoic acid can be found in a number of food items such as other cereal product, hyacinth bean, red rice, and elliotts blueberry, which makes 16-hydroxy-hexadecanoic acid a potential biomarker for the consumption of these food products.

   

Oleic acid

Emersol 221 low titer white oleic acid

C18H34O2 (282.2559)


Oleic acid (or 9Z)-Octadecenoic acid) is an unsaturated C-18 or an omega-9 fatty acid that is the most widely distributed and abundant fatty acid in nature. It occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish. The name derives from the Latin word oleum, which means oil. Oleic acid is the most abundant fatty acid in human adipose tissue, and the second most abundant in human tissues overall, following palmitic acid. Oleic acid is a component of the normal human diet, being a part of animal fats and vegetable oils. Triglycerides of oleic acid represent the majority of olive oil (about 70\\\\%). Oleic acid triglycerides also make up 59–75\\\\% of pecan oil, 61\\\\% of canola oil, 36–67\\\\% of peanut oil, 60\\\\% of macadamia oil, 20–80\\\\% of sunflower oil, 15–20\\\\% of grape seed oil, sea buckthorn oil, 40\\\\% of sesame oil, and 14\\\\% of poppyseed oil. High oleic variants of plant sources such as sunflower (~80\\\\%) and canola oil (70\\\\%) also have been developed. consumption has been associated with decreased low-density lipoprotein (LDL) cholesterol, and possibly with increased high-density lipoprotein (HDL) cholesterol, however, the ability of oleic acid to raise HDL is still debated. Oleic acid may be responsible for the hypotensive (blood pressure reducing) effects of olive oil that is considered a health benefit. Oleic acid is used in manufacturing of surfactants, soaps, plasticizers. It is also used as an emulsifying agent in foods and pharmaceuticals. Oleic acid is used commercially in the preparation of oleates and lotions, and as a pharmaceutical solvent. Major constituent of plant oils e.g. olive oil (ca. 80\\\\%), almond oil (ca. 80\\\\%) and many others, mainly as glyceride. Constituent of tall oiland is also present in apple, melon, raspberry oil, tomato, banana, roasted peanuts, black tea, rice bran, cardamon, plum brandy, peated malt, dairy products and various animal fats. Component of citrus fruit coatings. Emulsifying agent in foods CONFIDENCE standard compound; INTERNAL_ID 290 COVID info from WikiPathways Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS Oleic acid (9-cis-Octadecenoic acid) is an abundant monounsaturated fatty acid[1]. Oleic acid is a Na+/K+ ATPase activator[2]. Oleic acid (9-cis-Octadecenoic acid) is an abundant monounsaturated fatty acid[1]. Oleic acid is a Na+/K+ ATPase activator[2].

   

L-Lactic acid

1-Hydroxyethane 1-carboxylic acid

C3H6O3 (90.0317)


Lactic acid is an organic acid. It is a chiral molecule, consisting of two optical isomers, L-lactic acid and D-lactic acid, with the L-isomer being the most common in living organisms. Lactic acid plays a role in several biochemical processes and is produced in the muscles during intense activity. In animals, L-lactate is constantly produced from pyruvate via the enzyme lactate dehydrogenase (LDH) in a process of fermentation during normal metabolism and exercise. It does not increase in concentration until the rate of lactate production exceeds the rate of lactate removal. This is governed by a number of factors, including monocarboxylate transporters, lactate concentration, the isoform of LDH, and oxidative capacity of tissues. The concentration of blood lactate is usually 1-2 mmol/L at rest, but can rise to over 20 mmol/L during intense exertion. There are some indications that lactate, and not glucose, is preferentially metabolized by neurons in the brain of several mammalian species, including mice, rats, and humans. Glial cells, using the lactate shuttle, are responsible for transforming glucose into lactate, and for providing lactate to the neurons. Lactate measurement in critically ill patients has been traditionally used to stratify patients with poor outcomes. However, plasma lactate levels are the result of a finely tuned interplay of factors that affect the balance between its production and its clearance. When the oxygen supply does not match its consumption, organisms adapt in many different ways, up to the point when energy failure occurs. Lactate, being part of the adaptive response, may then be used to assess the severity of the supply/demand imbalance. In such a scenario, the time to intervention becomes relevant: early and effective treatment may allow tissues and cells to revert to a normal state, as long as the oxygen machinery (i.e. mitochondria) is intact. Conversely, once the mitochondria are deranged, energy failure occurs even in the presence of normoxia. The lactate increase in critically ill patients may, therefore, be viewed as an early marker of a potentially reversible state (PMID: 16356243). When present in sufficiently high levels, lactic acid can act as an oncometabolite, an immunosuppressant, an acidogen, and a metabotoxin. An oncometabolite is a compound that promotes tumor growth and survival. An immunosuppressant reduces or arrests the activity of the immune system. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of lactic acid are associated with at least a dozen inborn errors of metabolism, including 2-methyl-3-hydroxybutyryl CoA dehydrogenase deficiency, biotinidase deficiency, fructose-1,6-diphosphatase deficiency, glycogen storage disease type 1A (GSD1A) or Von Gierke disease, glycogenosis type IB, glycogenosis type IC, glycogenosis type VI, Hers disease, lactic acidemia, Leigh syndrome, methylmalonate semialdehyde dehydrogenase deficiency, pyruvate decarboxylase E1 component deficiency, pyruvate dehydrogenase complex deficiency, pyruvate dehydrogenase deficiency, and short chain acyl CoA dehydrogenase deficiency (SCAD deficiency). Locally high concentrations of lactic acid or lactate are found near many tumors due to the upregulation of lactate dehydrogenase (PMID: 15279558). Lactic acid produced by tumors through aerobic glycolysis acts as an immunosuppressant and tumor promoter (PMID: 23729358). Indeed, lactic acid has been found to be a key player or regulator in the development and malignant progression of a variety of cancers (PMID: 22084445). A number of studies have demonstrated that malignant transformation is associated with an increase in aerobic cellular lactate excretion. Lactate concentrations in various carcinomas (e.g. uterine cervix, head and neck, colorectal regi... Occurs in the juice of muscular tissue, bile etc. Flavour ingredient, food antioxidant. Various esters are also used in flavourings L-Lactic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=79-33-4 (retrieved 2024-07-01) (CAS RN: 79-33-4). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Lactate (Lactate acid) is the product of glycolysis. Lactate is produced by oxygen lack in contracting skeletal muscle in vivo, and can be removed under fully aerobic conditions. Lactate can be as a hemodynamic marker in the critically ill[1][2]. Lactate (Lactate acid) is the product of glycolysis. Lactate is produced by oxygen lack in contracting skeletal muscle in vivo, and can be removed under fully aerobic conditions. Lactate can be as a hemodynamic marker in the critically ill[1][2]. L-Lactic acid is a buildiing block which can be used as a precursor for the production of the bioplastic polymer poly-lactic acid. L-Lactic acid is a buildiing block which can be used as a precursor for the production of the bioplastic polymer poly-lactic acid.

   

Aspirin

2-Acetoxybenzenecarboxylic acid

C9H8O4 (180.0423)


Aspirin is only found in individuals who have consumed this drug. Aspirin or acetylsalicylic acid (acetosal) is a drug in the family of salicylates, often used as an analgesic (against minor pains and aches), antipyretic (against fever), and anti-inflammatory. It has also an anticoagulant effect and is used in long-term low-doses to prevent heart attacks and cancer. It was isolated from meadowsweet (Filipendula ulmaria, formerly classified as Spiraea ulmaria) by German researchers in 1839. While their extract was somewhat effective, it also caused digestive problems such as irritated stomach and diarrhoea, and even death when consumed in high doses. In 1853, a French chemist named Charles Frederic Gerhardt neutralized salicylic acid by buffering it with sodium (sodium salicylate) and acetyl chloride, creating acetosalicylic anhydride. Gerhardts product worked, but he had no desire to market it and abandoned his discovery. In 1897, researcher Arthur Eichengrun and Felix Hoffmann, a research assistant at Friedrich Bayer & Co. in Germany, derivatized one of the hydroxyl functional groups in salicylic acid with an acetyl group (forming the acetyl ester), which greatly reduced the negative effects. This was the first synthetic drug, not a copy of something that existed in nature, and the start of the pharmaceuticals industry. The name aspirin is composed of a- (from the acetyl group) -spir- (from the plant genus Spiraea) and -in (a common ending for drugs at the time). It has also been stated that the name originated by another means. As referring to AcetylSalicylic and pir in reference to one of the scientists who was able to isolate it in crystalline form, Raffaele Piria. Finally in due to the same reasons as stated above. Salicylic acid (which is a naturally occurring substance found in many plants) can be acetylated using acetic anhydride, yielding aspirin and acetic acid as a byproduct. It is a common experiment performed in organic chemistry labs, and generally tends to produce low yields due to the relative difficulty of its extraction from an aqueous state. The trick to getting the reaction to work is to acidify with phosphoric acid and heat the reagents under reflux with a boiling water bath for between 40 minutes and an hour. Aspirin acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. (From Martindale, The Extra Pharmacopoeia, 30th ed, p5). B - Blood and blood forming organs > B01 - Antithrombotic agents > B01A - Antithrombotic agents > B01AC - Platelet aggregation inhibitors excl. heparin N - Nervous system > N02 - Analgesics > N02B - Other analgesics and antipyretics > N02BA - Salicylic acid and derivatives D018501 - Antirheumatic Agents > D000894 - Anti-Inflammatory Agents, Non-Steroidal > D016861 - Cyclooxygenase Inhibitors Constituent of Glycyrrhiza glabra variety typica (licorice) roots. Acetylsalicylic acid is found in herbs and spices. D000893 - Anti-Inflammatory Agents > D000894 - Anti-Inflammatory Agents, Non-Steroidal > D012459 - Salicylates A - Alimentary tract and metabolism > A01 - Stomatological preparations > A01A - Stomatological preparations COVID info from clinicaltrial, clinicaltrials, clinical trial, clinical trials, COVID-19 Disease Map C78272 - Agent Affecting Nervous System > C241 - Analgesic Agent > C2198 - Nonnarcotic Analgesic D018373 - Peripheral Nervous System Agents > D018689 - Sensory System Agents C471 - Enzyme Inhibitor > C1323 - Cyclooxygenase Inhibitor > C287 - Aspirin D006401 - Hematologic Agents > D010975 - Platelet Aggregation Inhibitors D002491 - Central Nervous System Agents > D000700 - Analgesics D006401 - Hematologic Agents > D005343 - Fibrinolytic Agents CONFIDENCE standard compound; EAWAG_UCHEM_ID 3578 D050299 - Fibrin Modulating Agents D002317 - Cardiovascular Agents D004791 - Enzyme Inhibitors D058633 - Antipyretics Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS

   

Linoleic acid

C18:2 9C, 12C Omega6 todos cis-9,12-octadienoico

C18H32O2 (280.2402)


Linoleic acid is a doubly unsaturated fatty acid, also known as an omega-6 fatty acid, occurring widely in plant glycosides. In this particular polyunsaturated fatty acid (PUFA), the first double bond is located between the sixth and seventh carbon atom from the methyl end of the fatty acid (n-6). Linoleic acid is an essential fatty acid in human nutrition because it cannot be synthesized by humans. It is used in the biosynthesis of prostaglandins (via arachidonic acid) and cell membranes (From Stedman, 26th ed). Linoleic acid is found to be associated with isovaleric acidemia, which is an inborn error of metabolism. Linoleic acid (LA) is an organic compound with the formula HOOC(CH2)7CH=CHCH2CH=CH(CH2)4CH3. Both alkene groups (−CH=CH−) are cis. It is a fatty acid sometimes denoted 18:2 (n-6) or 18:2 cis-9,12. A linoleate is a salt or ester of this acid.[5] Linoleic acid is a polyunsaturated, omega-6 fatty acid. It is a colorless liquid that is virtually insoluble in water but soluble in many organic solvents.[2] It typically occurs in nature as a triglyceride (ester of glycerin) rather than as a free fatty acid.[6] It is one of two essential fatty acids for humans, who must obtain it through their diet,[7] and the most essential, because the body uses it as a base to make the others. The word "linoleic" derives from Latin linum 'flax', and oleum 'oil', reflecting the fact that it was first isolated from linseed oil.

   

Heptanoic acid

1-Hexanecarboxylic acid

C7H14O2 (130.0994)


Heptanoic acid, or C7:0 also known as enanthic acid or heptylic acid, belongs to the class of organic compounds known as medium-chain fatty acids. Medium-chain fatty acids (MCFA) are fatty acids with aliphatic tails of 6 to 12 carbons, which can form medium-chain triglycerides Heptanoic acid is an oily liquid with an unpleasant, rancid odor. It contributes to the odor of some rancid oils. It is slightly soluble in water, but very soluble in ethanol and ether. Its name derives from the Latin oenanthe which is in turn derived from the Ancient Greek oinos "wine" and anthos "blossom." Heptanoic acid is used in the preparation of esters, such as ethyl enanthate, which are used in fragrances and as artificial flavors. The triglyceride ester of heptanoic acid is the triheptanoin, which is used in certain medical conditions as a nutritional supplement. Present in essential oils, e.g. violet leaf oil, palm oiland is also present in apple, feijoa fruit, strawberry jam, clove bud, ginger, black tea, morello cherry, grapes, rice bran and other foodstuffs. Flavouring ingredient. It is used as one of the components in washing solns. used to assist lye peeling of fruit and vegetables

   

Sebacic acid

Sebacic acid, monocadmium salt

C10H18O4 (202.1205)


Sebacic acid is a saturated, straight-chain naturally occurring dicarboxylic acid with 10 carbon atoms. Sebacic acid is a normal urinary acid. In patients with multiple acyl-CoA-dehydrogenase deficiency (MADD), also known as glutaric aciduria type II (GAII), a group of metabolic disorders due to deficiency of either electron transfer flavoprotein or electron transfer flavoprotein ubiquinone oxidoreductase, biochemical data shows an increase in urine sebacic acid excretion. Sebacic acid is found to be associated with carnitine-acylcarnitine translocase deficiency and medium chain acyl-CoA dehydrogenase deficiency, which are inborn errors of metabolism. Sebacic acid is a white flake or powdered crystal slightly soluble in water that has been proposed as an alternative energy substrate in total parenteral nutrition. Sebacic Acid was named from the Latin sebaceus (tallow candle) or sebum (tallow) in reference to its use in the manufacture of candles. Sebacic acid and its derivatives such as azelaic acid have a variety of industrial uses as plasticizers, lubricants, hydraulic fluids, cosmetics, candles, etc. It is used in the synthesis of polyamide and alkyd resins. It is also used as an intermediate for aromatics, antiseptics and painting materials (PMID: 10556649, 1738216, 8442769, 12706375). Sebacic acid is a saturated, straight-chain naturally occurring dicarboxylic acid with 10 carbon atoms. Sebacic acid is a normal urinary acid. In patients with multiple acyl-CoA-dehydrogenase deficiency (MADD) or glutaric aciduria type II (GAII) are a group of metabolic disorders due to deficiency of either electron transfer flavoprotein or electron transfer flavoprotein ubiquinone oxidoreductase, biochemical data shows an increase in urine sebacic acid excretion. CONFIDENCE standard compound; INTERNAL_ID 671; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 4109; ORIGINAL_PRECURSOR_SCAN_NO 4104 CONFIDENCE standard compound; INTERNAL_ID 671; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 4132; ORIGINAL_PRECURSOR_SCAN_NO 4130 CONFIDENCE standard compound; INTERNAL_ID 671; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 4118; ORIGINAL_PRECURSOR_SCAN_NO 4114 CONFIDENCE standard compound; INTERNAL_ID 671; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 4132; ORIGINAL_PRECURSOR_SCAN_NO 4129 CONFIDENCE standard compound; INTERNAL_ID 671; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 4099; ORIGINAL_PRECURSOR_SCAN_NO 4095 CONFIDENCE standard compound; INTERNAL_ID 671; DATASET 20200303_ENTACT_RP_MIX506; DATA_PROCESSING MERGING RMBmix ver. 0.2.7; DATA_PROCESSING PRESCREENING Shinyscreen ver. 0.8.0; ORIGINAL_ACQUISITION_NO 4127; ORIGINAL_PRECURSOR_SCAN_NO 4123 Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID S017 Decanedioic acid, a normal urinary acid, is found to be associated with carnitine-acylcarnitine translocase deficiency and medium chain acyl-CoA dehydrogenase deficiency. Decanedioic acid, a normal urinary acid, is found to be associated with carnitine-acylcarnitine translocase deficiency and medium chain acyl-CoA dehydrogenase deficiency.

   

Lignoceric acid (C24)

Tetracosanoic acid

C24H48O2 (368.3654)


Lignoceric acid, also known as N-tetracosanoic acid or tetraeicosanoate, is a member of the class of compounds known as very long-chain fatty acids. Very long-chain fatty acids are fatty acids with an aliphatic tail that contains at least 22 carbon atoms. Thus, lignoceric acid is considered to be a fatty acid lipid molecule. Lignoceric acid is practically insoluble (in water) and a weakly acidic compound (based on its pKa). Lignoceric acid can be found in a number of food items such as hazelnut, cheese, rye bread, and cetacea (dolphin, porpoise, whale), which makes lignoceric acid a potential biomarker for the consumption of these food products. Lignoceric acid can be found primarily in blood and feces, as well as in human fibroblasts tissue. Lignoceric acid exists in all eukaryotes, ranging from yeast to humans. In humans, lignoceric acid is involved in a couple of metabolic pathways, which include adrenoleukodystrophy, x-linked and beta oxidation of very long chain fatty acids. Lignoceric acid is also involved in carnitine-acylcarnitine translocase deficiency, which is a metabolic disorder. Lignoceric acid, or tetracosanoic acid, is the saturated fatty acid with formula C23H47COOH. It is found in wood tar, various cerebrosides, and in small amounts in most natural fats. The fatty acids of peanut oil contain small amounts of lignoceric acid (1.1\\\\% – 2.2\\\\%). This fatty acid is also a byproduct of lignin production . Tetracosanoic acid is a C24 straight-chain saturated fatty acid. It has a role as a volatile oil component, a plant metabolite, a human metabolite and a Daphnia tenebrosa metabolite. It is a very long-chain fatty acid and a straight-chain saturated fatty acid. It is a conjugate acid of a tetracosanoate. Tetracosanoic acid, also known as N-tetracosanoate or lignoceric acid, belongs to the class of organic compounds known as very long-chain fatty acids. These are fatty acids with an aliphatic tail that contains at least 22 carbon atoms. Tetracosanoic acid is a very hydrophobic molecule, practically insoluble in water, and relatively neutral. Tetracosanoic acid is a potentially toxic compound. Acquisition and generation of the data is financially supported in part by CREST/JST. Lignoceric acid (Tetracosanoic acid) is a 24-carbon saturated (24:0) fatty acid, which is synthesized in the developing brain. Lignoceric acid is also a by-product of lignin production. Lignoceric acid can be used for Zellweger cerebro‐hepato‐renal syndrome and adrenoleukodystrophy research[1][2]. Lignoceric acid (Tetracosanoic acid) is a 24-carbon saturated (24:0) fatty acid, which is synthesized in the developing brain. Lignoceric acid is also a by-product of lignin production. Lignoceric acid can be used for Zellweger cerebro‐hepato‐renal syndrome and adrenoleukodystrophy research[1][2].

   

Isocitric acid

3-carboxy-2,3-dideoxy-1-hydroxypropan-1,2,3-tricarboxylic acid

C6H8O7 (192.027)


Isocitric acid, also known as isocitrate belongs to the class of organic compounds known as tricarboxylic acids and derivatives. These are carboxylic acids containing exactly three carboxyl groups. Isocitric acid is a TCA (tricarboxylic acid) cycle intermediate. It is a structural isomer of citric acid and is formed from citrate with the help of the enzyme aconitase. More specifically, Isocitric acid is synthesized from citric acid via the intermediate cis-aconitic acid by the enzyme aconitase (aconitate hydratase). Isocitrate is acted upon by isocitrate dehydrogenase (IDH) to form alpha-ketoglutarate. This is a two-step process, which involves oxidation of isocitrate to oxalosuccinate (a ketone), followed by the decarboxylation of the carboxyl group beta to the ketone, forming alpha-ketoglutarate. In humans, IDH exists in three isoforms: IDH3 catalyzes the third step of the citric acid cycle while converting NAD+ to NADH in the mitochondria. The isoforms IDH1 and IDH2 catalyze the same reaction outside the context of the citric acid cycle and use NADP+ as a cofactor instead of NAD+. They localize to the cytosol as well as the mitochondrion and peroxisome. Isocitric acid exists in all living species, ranging from bacteria to plants to humans. Isocitric acid is a minor organic acid found in most fruit juices, especially in blackberries, youngberries, and boyberries, and in vegetables, especially in carrots. The determination of D-isocitric acid has become of importance in the analysis of fruit juices for the detection of illegal additives (adulteration). Since the quantities of citric and isocitric acids are correlated in fruit juices, a high ratio of citric to isocitric acid can indicate the addition of citric acid as an alduterant. In authentic orange juice, for example, the ratio of citric acid to D-isocitric acid is usually less than 130. Isocitric acid is mostly used in the food industry (food additive) as a food acidulant. The citrate oxidation to isocitrate is catalyzed by the enzyme aconitase. Human prostatic secretion is remarkably rich in citric acid and low aconitase activity will therefore play a significant role in enabling accumulation of high citrate levels (PubMed ID 8115279) [HMDB]. Isocitric acid is found in many foods, some of which are wild carrot, redcurrant, carrot, and soursop. [Spectral] Isocitrate (exact mass = 192.027) and CDP (exact mass = 403.01818) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Isocitric acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=320-77-4 (retrieved 2024-07-01) (CAS RN: 320-77-4). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). Isocitric acid is an endogenous metabolite present in Saliva and Cellular_Cytoplasm that can be used for the research of Alzheimer's Disease, Lewy Body Dementia and Anoxia[1][2][3]. Isocitric acid is an endogenous metabolite present in Saliva and Cellular_Cytoplasm that can be used for the research of Alzheimer's Disease, Lewy Body Dementia and Anoxia[1][2][3].

   

Glycolic acid

Glycolic acid, monopotassium salt

C2H4O3 (76.016)


Glycolic acid (or hydroxyacetic acid) is the smallest alpha-hydroxy acid (AHA). This colourless, odourless, and hygroscopic crystalline solid is highly soluble in water. Due to its excellent capability to penetrate skin, glycolic acid is often used in skin care products, most often as a chemical peel. It may reduce wrinkles, acne scarring, and hyperpigmentation and improve many other skin conditions, including actinic keratosis, hyperkeratosis, and seborrheic keratosis. Once applied, glycolic acid reacts with the upper layer of the epidermis, weakening the binding properties of the lipids that hold the dead skin cells together. This allows the outer skin to dissolve, revealing the underlying skin. It is thought that this is due to the reduction of calcium ion concentrations in the epidermis and the removal of calcium ions from cell adhesions, leading to desquamation. Glycolic acid is a known inhibitor of tyrosinase. This can suppress melanin formation and lead to a lightening of skin colour. Acute doses of glycolic acid on skin or eyes leads to local effects that are typical of a strong acid (e.g. dermal and eye irritation). Glycolate is a nephrotoxin if consumed orally. A nephrotoxin is a compound that causes damage to the kidney and kidney tissues. Glycolic acids renal toxicity is due to its metabolism to oxalic acid. Glycolic and oxalic acid, along with excess lactic acid, are responsible for the anion gap metabolic acidosis. Oxalic acid readily precipitates with calcium to form insoluble calcium oxalate crystals. Renal tissue injury is caused by widespread deposition of oxalate crystals and the toxic effects of glycolic acid. Glycolic acid does exhibit some inhalation toxicity and can cause respiratory, thymus, and liver damage if present in very high levels over long periods of time. Elevated glycolic acid without elevated oxalic acid is most likely a result of GI yeast overgrowth (Aspergillus, Penicillium, probably Candida) or due to dietary sources containing glycerol (glycerine). (http://drweyrich.weyrich.com/labs/oat.html). Glycolic acid has also been found to be a metabolite in Acetobacter, Acidithiobacillus, Alcaligenes, Corynebacterium, Cryptococcus, Escherichia, Gluconobacter, Kluyveromyces, Leptospirillum, Pichia, Rhodococcus, Rhodotorula and Saccharomyces (PMID: 11758919; PMID: 26360870; PMID: 14390024). D003879 - Dermatologic Agents > D007641 - Keratolytic Agents Found in sugar cane (Saccharum officinarum) KEIO_ID G012 Glycolic acid is an inhibitor of tyrosinase, suppressing melanin formation and lead to a lightening of skin colour. Glycolic acid is an inhibitor of tyrosinase, suppressing melanin formation and lead to a lightening of skin colour.

   

Malonate

Malonic acid, disodium salt, 1-(14)C-labeled

C3H4O4 (104.011)


Malonic acid (IUPAC systematic name: propanedioic acid) is a dicarboxylic acid with structure CH2(COOH)2. The ionised form of malonic acid, as well as its esters and salts, are known as malonates. For example, diethyl malonate is malonic acids ethyl ester. The name originates from Latin malum, meaning apple. Malonic acid is the archetypal example of a competitive inhibitor: it acts against succinate dehydrogenase (complex II) in the respiratory electron transport chain.; Malonic acid (IUPAC systematic name: propanedioic acid) is a dicarboxylic acid with structure CH2(COOH)2. The ionised form of malonic acid, as well as its esters and salts, are known as malonates. For example, diethyl malonate is malonic acids ethyl ester. The name originates from the Greek word ????? (malon) meaning apple. Propanedioic acid is found in many foods, some of which are green bell pepper, red bell pepper, common beet, and sweet orange. Malonic acid (IUPAC systematic name: propanedioic acid) is a dicarboxylic acid with structure CH2(COOH)2. The ionised form of malonic acid, as well as its esters and salts, are known as malonates. For example, diethyl malonate is malonic acids ethyl ester. The name originates from Latin malum, meaning apple. Malonic acid is the archetypal example of a competitive inhibitor: it acts against succinate dehydrogenase (complex II) in the respiratory electron transport chain. Malonic acid is found to be associated with malonyl-CoA decarboxylase deficiency, which is an inborn error of metabolism. Malonic acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=141-82-2 (retrieved 2024-07-02) (CAS RN: 141-82-2). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0).

   

Alpha-ketobutyrate

2-oxobutanoic acid

C4H6O3 (102.0317)


3-methyl pyruvic acid, also known as alpha-ketobutyric acid or 2-oxobutyric acid, belongs to short-chain keto acids and derivatives class of compounds. Those are keto acids with an alkyl chain the contains less than 6 carbon atoms. Thus, 3-methyl pyruvic acid is considered to be a fatty acid lipid molecule. 3-methyl pyruvic acid is soluble (in water) and a weakly acidic compound (based on its pKa). 3-methyl pyruvic acid can be found in a number of food items such as pepper (c. baccatum), triticale, european plum, and black walnut, which makes 3-methyl pyruvic acid a potential biomarker for the consumption of these food products. 3-methyl pyruvic acid can be found primarily in blood, cerebrospinal fluid (CSF), saliva, and urine. 3-methyl pyruvic acid exists in all living species, ranging from bacteria to humans. In humans, 3-methyl pyruvic acid is involved in several metabolic pathways, some of which include methionine metabolism, homocysteine degradation, threonine and 2-oxobutanoate degradation, and propanoate metabolism. 3-methyl pyruvic acid is also involved in several metabolic disorders, some of which include dimethylglycine dehydrogenase deficiency, methylenetetrahydrofolate reductase deficiency (MTHFRD), s-adenosylhomocysteine (SAH) hydrolase deficiency, and hyperglycinemia, non-ketotic. 2-Ketobutyric acid, also known as alpha-ketobutyrate or 2-oxobutyrate, belongs to the class of organic compounds known as short-chain keto acids and derivatives. These are keto acids with an alkyl chain the contains less than 6 carbon atoms. 2-Ketobutyric acid is a substance that is involved in the metabolism of many amino acids (glycine, methionine, valine, leucine, serine, threonine, isoleucine) as well as propanoate metabolism and C-5 branched dibasic acid metabolism. It is also one of the degradation products of threonine. It can be converted into propionyl-CoA (and subsequently methylmalonyl CoA, which can be converted into succinyl CoA, a citric acid cycle intermediate), and thus enter the citric acid cycle. More specifically, 2-ketobutyric acid is a product of the lysis of cystathionine. 2-Oxobutanoic acid is a product in the enzymatic cleavage of cystathionine.

   

Succinic acid semialdehyde

Succinic semialdehyde, calcium salt

C4H6O3 (102.0317)


Succinic acid semialdehyde (or succinate semialdehyde) is an intermediate in the catabolism of gamma-aminobutyrate or GABA (PMID:16435183). It is formed from GABA by the action of GABA transaminase, which leads to the production of succinate semialdehyde and alanine. The resulting succinate semialdehyde is further oxidized by succinate semialdehyde dehydrogenase to become succinic acid, which also yields NADPH. Under certain situations, high levels of succinate semialdehyde can function as a neurotoxin and a metabotoxin. A neurotoxin is a compound that causes damage to the brain and nerve tissues. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Elevated serum levels of succinate semialdehyde are found in succinic semialdehyde dehydrogenase (SSADH) deficiency (gamma-hydroxybutyric aciduria), a rare neurometabolic disorder of gamma-aminobutyric acid (GABA) degradation. Symptoms include motor delay, hypotonia, speech delay, autistic features, seizures, and ataxia. Patients also exhibit behavioural problems such as attention deficit, hyperactivity, anxiety, or aggression (PMID:18622364). Succinate semialdehyde is considered a reactive carbonyl and may lead to increased oxidative stress. This stress is believed to contribute to the formation of free radicals in the brain tissue of animal models induced with SSADH deficiency, which further leads to secondary cell damage and death. Additionally, oxidative stress may be responsible for the loss of striatal dopamine, which may contribute to the neuropathology of SSADH deficiency. Succinic acid semialdehyde is an intermediate in the catabolism of gamma-aminobutyrate (PMID 16435183). Succinate semialdehyde dehydrogenase is an enzyme that catalyses the reaction of succinate semialdehyde and NAD+ to form succinate and NADH. Succinic semialdehyde dehydrogenase (SSADH) deficiency (gamma-hydroxybutyric aciduria) is a rare neurometabolic disorder of gamma-aminobutyric acid degradation. Symptoms include motor delay, hypotonia, speech delay, autistic features, seizures, and ataxia. Patients also exhibit behavioral problems, such as attention deficit, hyperactivity, anxiety, or aggression. (PMID: 18622364) [HMDB]. Succinic acid semialdehyde is found in many foods, some of which are yellow zucchini, japanese chestnut, banana, and pineappple sage.

   

Valerate

N-Pentanoic acid, 11C-labeled sodium salt

C5H10O2 (102.0681)


Valeric acid, or pentanoic acid, is a straight chain alkyl carboxylic acid with the chemical formula CH3(CH2)3COOH. Like other low molecular weight carboxylic acids, it has a very unpleasant odor. Valeric acid is commonly found in human feces, with an average concentration of 2.4 umol/g feces (range of 0.6-3.8 umol/g) (PMID:6740214). Valeric acid is produced by the gut microbiota, typically Clostridia species and other gut bacterial species such as Megasphaera massiliensis MRx0029 (PMID:30052654) via the condensation of ethanol with propionic acid (PMID:18116989). Valeric acid is largely considered as a gut microbial metabolite. Recently, valeric acid has been found to exert strong gut protective effects. Studies involving mice that received high doses of radiation showed that valeric acid replenishment (via oral gavage) elevated the survival rate of irradiated mice, protected hematogenic organs (such as the thymus and spleen), improved gastrointestinal (GI) tract function and enhanced intestinal epithelial integrity (PMID:31931652 ). Valeric acid was also found to restore the enteric bacteria taxonomic proportions and reprogram the small intestinal protein profile to normal levels. Valeric acid, like butyric acid, also appears to be a potent histone deacetylase (HDAC) inhibitor. High levels of HDAC proteins have been implicated in a variety of disease pathologies, from cancer and colitis to cardiovascular disease and neurodegeneration (PMID:30052654). Valeric acid is also found in certain plants, specifically in the perennial flowering plant valerian (Valeriana officinalis), from which it gets its name. Industrially valeric acid is primarily used is in the synthesis of its esters. Volatile esters of valeric acid tend to have pleasant odors and are used in perfumes and cosmetics. Ethyl valerate and pentyl valerate are used as food additives because of their fruity flavours. Hydrolysis of these valerate-containing food additives in the gut can also lead to the appearance of valerate in blood, urine and stool samples. Minor constituent of biological systems e.g. yeast fat, some plant oilsand is also present in blue cheeses, wines, apple, banana, morello cherry, cooked shrimp, scallop, roasted peanut, roasted filberts and other foodstuffs. Flavouring agent. Pentanoic acid is found in many foods, some of which are red raspberry, pepper (c. frutescens), tea, and fats and oils. KEIO_ID V002

   

4-Hydroxybutyric acid

4-Hydroxybutyric acid monosodium salt

C4H8O3 (104.0473)


4-Hydroxybutyric acid (also known as gamma-hydroxybutyrate or GHB) is a precursor and a metabolite of gamma-aminobutyric acid (GABA). GHB acts as a central nervous system (CNS) neuromodulator, mediating its effects through GABA and GHB-specific receptors, or by affecting dopamine transmission (PMID: 16620539). GHB occurs naturally in all mammals, but its function remains unknown. GHB is labeled as an illegal drug in most countries, but it also is used as a legal drug (Xyrem) in patients with narcolepsy. It is used illegally (under the street names juice, liquid ecstasy, or G) as an intoxicant for increasing athletic performance and as a date rape drug. In high doses, GHB inhibits the CNS, inducing sleep and inhibiting the respiratory drive. In lower doses, its euphoriant effect predominates (PMID: 17658710). When present in sufficiently high levels, 4-hydroxybutyric acid can act as an acidogen, a neurotoxin, and a metabotoxin. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A neurotoxin is a compound that adversely affects neural cells and tissues. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of 4-hydroxybutyric acid are associated with two inborn errors of metabolism: glutaric aciduria II and succinic semialdehyde dehydrogenase deficiency (SSADH). SSADH deficiency leads to a 30-fold increase of GHB and a 2-4 fold increase of GABA in the brains of patients with SSADH deficiency as compared to normal brain concentrations of the compounds. As an acidogen, 4-hydroxybutyric acid is an organic acid, and abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart abnormalities, kidney abnormalities, liver damage, seizures, coma, and possibly death. Many affected children with organic acidemias experience intellectual disability or delayed development. These are also the characteristic symptoms of the untreated IEMs mentioned above. Particularly for SSADH deficiency, the most common features observed include developmental delay, hypotonia, and intellectual disability. Nearly half of patients exhibit ataxia, seizures, behaviour problems, and hyporeflexia. In adults, acidosis or acidemia is characterized by headaches, confusion, feeling tired, tremors, sleepiness, and seizures. As a neurotoxin, GHB appears to affect both GABA (a neurotransmitter) signaling and glutamate signaling (another neurotransmitter). Glutamine metabolism may also play a role in the pathophysiology of excessive levels of GHB. High levels of GHB have been shown to depress both the NMDA and AMPA/kainite receptor-mediated functions and may also alter glutamatergic excitatory synaptic transmission as well. 4-Hydroxybutyric acid is a microbial metabolite found in Aeromonas, Escherichia and Pseudomonas (PMID: 19434404). 4-hydroxybutyric acid may cause bradycardia and dyskinesias.

   

γ-Aminobutyric acid

gamma-Aminobutyric acid, calcium salt (2:1)

C4H9NO2 (103.0633)


gamma-Aminobutyric acid (GABA) is an inhibitory neurotransmitter found in the nervous systems of widely divergent species, including humans. It is the chief inhibitory neurotransmitter in the vertebrate central nervous system. In vertebrates, GABA acts at inhibitory synapses in the brain. It acts by binding to specific transmembrane receptors in the plasma membrane of both pre- and postsynaptic neurons. This binding causes the opening of ion channels to allow either the flow of negatively-charged chloride ions into the cell or positively-charged potassium ions out of the cell. This will typically result in a negative change in the transmembrane potential, usually causing hyperpolarization. Three general classes of GABA receptor are known (PMID: 10561820). These include GABA-A and GABA-C ionotropic receptors, which are ion channels themselves, and GABA-B metabotropic receptors, which are G protein-coupled receptors that open ion channels via intermediaries known as G proteins (PMID: 10561820). Activation of the GABA-B receptor by GABA causes neuronal membrane hyperpolarization and a resultant inhibition of neurotransmitter release. In addition to binding sites for GABA, the GABA-A receptor has binding sites for benzodiazepines, barbiturates, and neurosteroids. GABA-A receptors are coupled to chloride ion channels. Therefore, activation of the GABA-A receptor induces increased inward chloride ion flux, resulting in membrane hyperpolarization and neuronal inhibition (PMID: 10561820). After release into the synapse, free GABA that does not bind to either the GABA-A or GABA-B receptor complexes can be taken up by neurons and glial cells. Four different GABA membrane transporter proteins (GAT-1, GAT-2, GAT-3, and BGT-1), which differ in their distribution in the CNS, are believed to mediate the uptake of synaptic GABA into neurons and glial cells. The GABA-A receptor subtype regulates neuronal excitability and rapid changes in fear arousal, such as anxiety, panic, and the acute stress response (PMID: 10561820). Drugs that stimulate GABA-A receptors, such as the benzodiazepines and barbiturates, have anxiolytic and anti-seizure effects via GABA-A-mediated reduction of neuronal excitability, which effectively raises the seizure threshold. GABA-A antagonists produce convulsions in animals and there is decreased GABA-A receptor binding in a positron emission tomography (PET) study of patients with panic disorder. Neurons that produce GABA as their output are called GABAergic neurons and have chiefly inhibitory action at receptors in the vertebrate. Medium spiny neurons (MSNs) are a typical example of inhibitory CNS GABAergic cells. GABA has been shown to have excitatory roles in the vertebrate, most notably in the developing cortex. Organisms synthesize GABA from glutamate using the enzyme L-glutamic acid decarboxylase and pyridoxal phosphate as a cofactor (PMID: 12467378). It is worth noting that this involves converting the principal excitatory neurotransmitter (glutamate) into the principal inhibitory one (GABA). Drugs that act as agonists of GABA receptors (known as GABA analogs or GABAergic drugs), or increase the available amount of GABA typically have relaxing, anti-anxiety, and anti-convulsive effects. GABA is found to be deficient in cerebrospinal fluid and the brain in many studies of experimental and human epilepsy. Benzodiazepines (such as Valium) are useful in status epilepticus because they act on GABA receptors. GABA increases in the brain after administration of many seizure medications. Hence, GABA is clearly an antiepileptic nutrient. Inhibitors of GAM metabolism can also produce convulsions. Spasticity and involuntary movement syndromes, such as Parkinsons, Friedreichs ataxia, tardive dyskinesia, and Huntingtons chorea, are all marked by low GABA when amino acid levels are studied. Trials of 2 to 3 g of GABA given orally have been effective in various epilepsy and spasticity syndromes. Agents that elevate GABA are als... Gamma-aminobutyric acid, also known as gaba or 4-aminobutanoic acid, belongs to gamma amino acids and derivatives class of compounds. Those are amino acids having a (-NH2) group attached to the gamma carbon atom. Thus, gamma-aminobutyric acid is considered to be a fatty acid lipid molecule. Gamma-aminobutyric acid is soluble (in water) and a weakly acidic compound (based on its pKa). Gamma-aminobutyric acid can be synthesized from butyric acid. Gamma-aminobutyric acid is also a parent compound for other transformation products, including but not limited to, (1S,2S,5S)-2-(4-glutaridylbenzyl)-5-phenylcyclohexan-1-ol, 4-(methylamino)butyric acid, and pregabalin. Gamma-aminobutyric acid can be found in a number of food items such as watercress, sour cherry, peach, and cardoon, which makes gamma-aminobutyric acid a potential biomarker for the consumption of these food products. Gamma-aminobutyric acid can be found primarily in most biofluids, including urine, cerebrospinal fluid (CSF), blood, and feces, as well as throughout most human tissues. Gamma-aminobutyric acid exists in all living species, ranging from bacteria to humans. In humans, gamma-aminobutyric acid is involved in a couple of metabolic pathways, which include glutamate metabolism and homocarnosinosis. Gamma-aminobutyric acid is also involved in few metabolic disorders, which include 2-hydroxyglutric aciduria (D and L form), 4-hydroxybutyric aciduria/succinic semialdehyde dehydrogenase deficiency, hyperinsulinism-hyperammonemia syndrome, and succinic semialdehyde dehydrogenase deficiency. Moreover, gamma-aminobutyric acid is found to be associated with alzheimers disease, hyper beta-alaninemia, tuberculous meningitis, and hepatic encephalopathy. Gamma-aminobutyric acid is a non-carcinogenic (not listed by IARC) potentially toxic compound. gamma-Aminobutyric acid (γ-Aminobutyric acid) (GABA ) is the chief inhibitory neurotransmitter in the mammalian central nervous system. Its principal role is reducing neuronal excitability throughout the nervous system. In humans, GABA is also directly responsible for the regulation of muscle tone . Chronically high levels of GABA are associated with at least 5 inborn errors of metabolism including: D-2-Hydroxyglutaric Aciduria, 4-Hydroxybutyric Aciduria/Succinic Semialdehyde Dehydrogenase Deficiency, GABA-Transaminase Deficiency, Homocarnosinosis and Succinic semialdehyde dehydrogenase deficiency (T3DB). [Spectral] 4-Aminobutanoate (exact mass = 103.06333) and D-2-Aminobutyrate (exact mass = 103.06333) were not completely separated on HPLC under the present analytical conditions as described in AC$XXX. Additionally some of the peaks in this data contains dimers and other unidentified ions. Acquisition and generation of the data is financially supported in part by CREST/JST. COVID info from clinicaltrial, clinicaltrials, clinical trial, clinical trials D018377 - Neurotransmitter Agents > D018682 - GABA Agents KEIO_ID A002 Corona-virus Coronavirus SARS-CoV-2 COVID-19 SARS-CoV COVID19 SARS2 SARS γ-Aminobutyric acid (4-Aminobutyric acid) is a major inhibitory neurotransmitter in the adult mammalian brain, binding to the ionotropic GABA receptors (GABAA receptors) and metabotropic receptors (GABAB receptors. γ-Aminobutyric acid shows calming effect by blocking specific signals of central nervous system[1][2]. γ-Aminobutyric acid (4-Aminobutyric acid) is a major inhibitory neurotransmitter in the adult mammalian brain, binding to the ionotropic GABA receptors (GABAA receptors) and metabotropic receptors (GABAB receptors. γ-Aminobutyric acid shows calming effect by blocking specific signals of central nervous system[1][2]. γ-Aminobutyric acid (4-Aminobutyric acid) is a major inhibitory neurotransmitter in the adult mammalian brain, binding to the ionotropic GABA receptors (GABAA receptors) and metabotropic receptors (GABAB receptors. γ-Aminobutyric acid shows calming effect by blocking specific signals of central nervous system[1][2].

   

Butyric acid

Butyric acid magnesium salt

C4H8O2 (88.0524)


Butyric acid is a short-chain fatty acid (SCFA) formed in the mammalian colon by bacterial fermentation of carbohydrates (including dietary fibre). It is a straight-chain alkyl carboxylic acid that appears as an oily, colorless liquid with an unpleasant (rancid butter) odor. The name butyric acid comes from the Greek word for "butter", the substance in which it was first found. Triglycerides of butyric acid constitute 3‚Äì4\\% of butter. When butter goes rancid, butyric acid is liberated from the short-chain triglycerides via hydrolysis. Butyric acid is a widely distributed SCFA and is found in all organisms ranging from bacteria to plants to animals. It is present in animal fat and plant oils, bovine milk, breast milk, butter, parmesan cheese, body odor and vomit. While butyric acid has an unpleasant odor, it does have a pleasant buttery taste. As a result, butyric acid is used as a flavoring agent in food manufacturing. Low-molecular-weight esters of butyric acid, such as methyl butyrate, also have very pleasant aromas or tastes. As a result, several butyrate esters are used as food and perfume additives. Butyrate is naturally produced by fermentation processes performed by obligate anaerobic bacteria found in the mammalian gut. It is a metabolite of several bacterial genera including Anaerostipes, Coprococcus, Eubacterium, Faecalibacterium and Roseburia (PMID: 12324374; PMID: 27446020). Highly-fermentable fiber residues, such as those from resistant starch, oat bran, pectin, and guar can be transformed by colonic bacteria into butyrate. One study found that resistant starch consistently produces more butyrate than other types of dietary fibre (PMID: 14747692). The production of butyrate from fibres in ruminant animals such as cattle is responsible for the butyrate content of milk and butter. Butyrate has a number of important biological functions and binds to several specific receptors. In humans, butyric acid is one of two primary endogenous agonists of human hydroxycarboxylic acid receptor 2 (HCA2), a G protein-coupled receptor. Like other SCFAs, butyrate is also an agonist at the free fatty acid receptors FFAR2 and FFAR3, which function as nutrient sensors that facilitate the homeostatic control of energy balance. Butyrate is essential to host immune homeostasis (PMID: 25875123). Butyrates effects on the immune system are mediated through the inhibition of class I histone deacetylases (specifically, HDAC1, HDAC2, HDAC3, and HDAC8) and activation of its G-protein coupled receptor targets including HCA2, FFAR2 and FFAR3. Among the short-chain fatty acids, butyrate is the most potent promoter of intestinal regulatory T cells in vitro and the only SCFA that is an HCA2 ligand (PMID: 25741338). Butyrate has been shown to be a critical mediator of the colonic inflammatory response. It possesses both preventive and therapeutic potential to counteract inflammation-mediated ulcerative colitis and colorectal cancer. As a short-chain fatty acid, butyrate is metabolized by mitochondria as an energy source through fatty acid metabolism. In particular, it is an important energy source for cells lining the mammalian colon (colonocytes). Without butyrate, colon cells undergo autophagy (i.e., self-digestion) and die. Butyric acid, also known as butyrate or butanoic acid, is a member of the class of compounds known as straight chain fatty acids. Straight chain fatty acids are fatty acids with a straight aliphatic chain. Thus, butyric acid is considered to be a fatty acid lipid molecule. Butyric acid is soluble (in water) and a weakly acidic compound (based on its pKa). Butyric acid can be found in a number of food items such as cinnamon, pepper (c. baccatum), burdock, and mandarin orange (clementine, tangerine), which makes butyric acid a potential biomarker for the consumption of these food products. Butyric acid can be found primarily in most biofluids, including saliva, breast milk, feces, and cerebrospinal fluid (CSF), as well as throughout most human tissues. Butyric acid exists in all eukaryotes, ranging from yeast to humans. In humans, butyric acid is involved in a couple of metabolic pathways, which include butyrate metabolism and fatty acid biosynthesis. Moreover, butyric acid is found to be associated with aIDS. Butyric acid is a non-carcinogenic (not listed by IARC) potentially toxic compound. Butyric acid was first observed in impure form in 1814 by the French chemist Michel Eugène Chevreul. By 1818, he had purified it sufficiently to characterize it. However, Chevreul did not publish his early research on butyric acid; instead, he deposited his findings in manuscript form with the secretary of the Academy of Sciences in Paris, France. Henri Braconnot, a French chemist, was also researching the composition of butter and was publishing his findings, and this led to disputes about priority. As early as 1815, Chevreul claimed that he had found the substance responsible for the smell of butter. By 1817, he published some of his findings regarding the properties of butyric acid and named it. However, it was not until 1823 that he presented the properties of butyric acid in detail. The name of butyric acid comes from the Latin word for butter, butyrum (or buturum), the substance in which butyric acid was first found . If the compound has been ingested, rapid gastric lavage should be performed using 5\\% sodium bicarbonate. For skin contact, the skin should be washed with soap and water. If the compound has entered the eyes, they should be washed with large quantities of isotonic saline or water. In serious cases, atropine and/or pralidoxime should be administered. Anti-cholinergic drugs work to counteract the effects of excess acetylcholine and reactivate AChE. Atropine can be used as an antidote in conjunction with pralidoxime or other pyridinium oximes (such as trimedoxime or obidoxime), though the use of -oximes has been found to be of no benefit, or possibly harmful, in at least two meta-analyses. Atropine is a muscarinic antagonist, and thus blocks the action of acetylcholine peripherally (T3DB). D018377 - Neurotransmitter Agents > D018494 - Histamine Agents > D006633 - Histamine Antagonists KEIO_ID B006

   

Diphenoxylate

Ethyl 1-(3-cyano-3,3-diphenylpropyl)-4-phenyl-4-piperidinecarboxylic acid

C30H32N2O2 (452.2464)


A meperidine congener used as an antidiarrheal, usually in combination with atropine. At high doses, it acts like morphine. Its unesterified metabolite difenoxin has similar properties and is used similarly. It has little or no analgesic activity. This medication is classified as a Schedule V under the Controlled Substances Act by the Food and Drug Administration (FDA) and the DEA in the United States when used in preparations. When diphenoxylate is used alone, it is classified as a Schedule II. A - Alimentary tract and metabolism > A07 - Antidiarrheals, intestinal antiinflammatory/antiinfective agents > A07D - Antipropulsives > A07DA - Antipropulsives D002491 - Central Nervous System Agents > D002492 - Central Nervous System Depressants > D009294 - Narcotics C78276 - Agent Affecting Digestive System or Metabolism > C266 - Antidiarrheal Agent D018373 - Peripheral Nervous System Agents > D018689 - Sensory System Agents D002491 - Central Nervous System Agents > D000700 - Analgesics D005765 - Gastrointestinal Agents > D000930 - Antidiarrheals

   

Methyl jasmonate

methyl 2-[(1R,2R)-3-oxo-2-[(2Z)-pent-2-en-1-yl]cyclopentyl]acetate

C13H20O3 (224.1412)


Acquisition and generation of the data is financially supported in part by CREST/JST. Flavouring ingredient. From Jasminum grandiflorum (royal jasmine) D006133 - Growth Substances > D010937 - Plant Growth Regulators lo Methyl 2-(3-oxo-2-(pent-2-en-1-yl)cyclopentyl)acetate is an endogenous metabolite. Methyl 2-(3-oxo-2-(pent-2-en-1-yl)cyclopentyl)acetate is an endogenous metabolite.

   

1-Aminocyclopropanecarboxylic acid

1-Aminocyclopropane-1-carboxylic acid hydrochloride

C4H7NO2 (101.0477)


1-aminocyclopropanecarboxylic acid, also known as acc or 1-amino-1-carboxycyclopropane, is a member of the class of compounds known as alpha amino acids. Alpha amino acids are amino acids in which the amino group is attached to the carbon atom immediately adjacent to the carboxylate group (alpha carbon). 1-aminocyclopropanecarboxylic acid is soluble (in water) and a moderately acidic compound (based on its pKa). 1-aminocyclopropanecarboxylic acid can be found in a number of food items such as american cranberry, chayote, sour cherry, and garden rhubarb, which makes 1-aminocyclopropanecarboxylic acid a potential biomarker for the consumption of these food products. ACC plays an important role in the biosynthesis of the plant hormone ethylene. It is synthesized by the enzyme ACC synthase ( EC 4.4.1.14) from methionine and converted to ethylene by ACC oxidase (EC 1.14.17.4) . 1-Aminocyclopropanecarboxylic acid is found in fruits. 1-Aminocyclopropanecarboxylic acid is isolated from apple and pear juice and cranberries. Acquisition and generation of the data is financially supported in part by CREST/JST. D002491 - Central Nervous System Agents > D018696 - Neuroprotective Agents D020011 - Protective Agents KEIO_ID A047 1-Aminocyclopropane-1-carboxylic acid is an endogenous metabolite.

   

D-Leucic acid

delta-2-Hydroxy-4-methylpentanoic acid

C6H12O3 (132.0786)


D-Leucic acid is an alpha-hydroxycarboxylic acid present in patients affected with Short-bowel syndrome (an Inborn errors of metabolism, OMIM 175200) (PMID 9766851), and in Maple Syrup Urine Disease (MSUD, an autosomal recessive inherited metabolic disorder of branched-chain amino acid) (PMID 9766851). [HMDB] D-Leucic acid is an alpha-hydroxycarboxylic acid present in patients affected with Short-bowel syndrome (an Inborn errors of metabolism, OMIM 175200) (PMID 9766851), and in Maple Syrup Urine Disease (MSUD, an autosomal recessive inherited metabolic disorder of branched-chain amino acid) (PMID 9766851). Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID H091 (R)-Leucic acid is an amino acid metabolite[1].

   

alpha-Hydroxyisobutyric acid

alpha-Hydroxy-alpha-methylpropanoic acid

C4H8O3 (104.0473)


Alpha-Hydroxyisobutyric acid is a metabolite of methyl tert-butyl ether (MTBE). MTBE may be obtained through environmental exposure. MTBE is rapidly eliminated from the body, mainly through expired air as the unchanged compound. MTBE is to some extent metabolised to t-butyl alcohol (TBA) and formaldehyde and oxidised to 2-methyl-1,2-propanediol and a-hydroxy isobuturic acid. Alpha-Hydroxyisobutyric acid has been used as an arial bactericide. [HMDB] alpha-Hydroxyisobutyric acid is a metabolite of methyl tert-butyl ether (MTBE). MTBE may be obtained through environmental exposure. MTBE is rapidly eliminated from the body, mainly through expired air as the unchanged compound. MTBE is to some extent metabolized to t-butyl alcohol (TBA) and formaldehyde and oxidized to 2-methyl-1,2-propanediol and alpha-hydroxyisobutyric acid. alpha-Hydroxyisobutyric acid has been used as an aerial bactericide. 2-Hydroxyisobutyric acid is an endogenous metabolite.

   

Ketoleucine

4-methyl-2-oxopentanoic acid

C6H10O3 (130.063)


Ketoleucine is an abnormal metabolite that arises from the incomplete breakdown of branched-chain amino acids. Ketoleucine is both a neurotoxin and a metabotoxin. A neurotoxin causes damage to nerve cells and nerve tissues. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of ketoleucine are associated with maple syrup urine disease (MSUD). MSUD is a metabolic disorder caused by a deficiency of the branched-chain alpha-keto acid dehydrogenase complex (BCKDC), leading to a buildup of the branched-chain amino acids (leucine, isoleucine, and valine) and their toxic by-products (ketoacids) in the blood and urine. The symptoms of MSUD often show in infancy and lead to severe brain damage if untreated. MSUD may also present later depending on the severity of the disease. If left untreated in older individuals, during times of metabolic crisis, symptoms of the condition include uncharacteristically inappropriate, extreme, or erratic behaviour and moods, hallucinations, anorexia, weight loss, anemia, diarrhea, vomiting, dehydration, lethargy, oscillating hypertonia and hypotonia, ataxia, seizures, hypoglycemia, ketoacidosis, opisthotonus, pancreatitis, rapid neurological decline, and coma. In maple syrup urine disease, the brain concentration of branched-chain ketoacids can increase 10- to 20-fold. This leads to a depletion of glutamate and a consequent reduction in the concentration of brain glutamine, aspartate, alanine, and other amino acids. The result is a compromise of energy metabolism because of a failure of the malate-aspartate shuttle and a diminished rate of protein synthesis (PMID: 15930465). Ketoleucine, also known as alpha-ketoisocaproic acid or 2-oxoisocaproate, belongs to short-chain keto acids and derivatives class of compounds. Those are keto acids with an alkyl chain the contains less than 6 carbon atoms. Ketoleucine is slightly soluble (in water) and a weakly acidic compound (based on its pKa). Ketoleucine can be found in a number of food items such as arctic blackberry, sesame, sea-buckthornberry, and soft-necked garlic, which makes ketoleucine a potential biomarker for the consumption of these food products. Ketoleucine can be found primarily in most biofluids, including saliva, blood, cerebrospinal fluid (CSF), and urine, as well as in human muscle, neuron and prostate tissues. Ketoleucine exists in all living species, ranging from bacteria to humans. In humans, ketoleucine is involved in the valine, leucine and isoleucine degradation. Ketoleucine is also involved in several metabolic disorders, some of which include methylmalonate semialdehyde dehydrogenase deficiency, propionic acidemia, 3-methylglutaconic aciduria type IV, and 3-methylglutaconic aciduria type I. Ketoleucine is a non-carcinogenic (not listed by IARC) potentially toxic compound. Ketoleucine is a metabolite that accumulates in Maple Syrup Urine Disease (MSUD) and shown to compromise brain energy metabolism by blocking the respiratory chain (T3DB). 4-Methyl-2-oxopentanoic acid (α-Ketoisocaproic acid), an abnormal metabolite, is both a neurotoxin and a metabotoxin.

   

alpha-Ketoisovaleric acid

3-Methyl-2-oxobutyric acid sodium salt

C5H8O3 (116.0473)


alpha-Ketoisovaleric acid is an abnormal metabolite that arises from the incomplete breakdown of branched-chain amino acids. alpha-Ketoisovaleric acid is a neurotoxin, an acidogen, and a metabotoxin. A neurotoxin causes damage to nerve cells and nerve tissues. An acidogen is an acidic compound that induces acidosis, which has multiple adverse effects on many organ systems. A metabotoxin is an endogenously produced metabolite that causes adverse health effects at chronically high levels. Chronically high levels of alpha-ketoisovaleric acid are associated with maple syrup urine disease. MSUD is a metabolic disorder caused by a deficiency of the branched-chain alpha-keto acid dehydrogenase complex (BCKDC), leading to a buildup of the branched-chain amino acids (leucine, isoleucine, and valine) and their toxic by-products (ketoacids) in the blood and urine. The symptoms of MSUD often show in infancy and lead to severe brain damage if untreated. MSUD may also present later depending on the severity of the disease. If left untreated in older individuals, during times of metabolic crisis, symptoms of the condition include uncharacteristically inappropriate, extreme, or erratic behaviour and moods, hallucinations, anorexia, weight loss, anemia, diarrhea, vomiting, dehydration, lethargy, oscillating hypertonia and hypotonia, ataxia, seizures, hypoglycemia, ketoacidosis, opisthotonus, pancreatitis, rapid neurological decline, and coma. In maple syrup urine disease, the brain concentration of branched-chain ketoacids can increase 10- to 20-fold. This leads to a depletion of glutamate and a consequent reduction in the concentration of brain glutamine, aspartate, alanine, and other amino acids. The result is a compromise of energy metabolism because of a failure of the malate-aspartate shuttle and a diminished rate of protein synthesis (PMID: 15930465). alpha-Ketoisovaleric acid is a keto-acid, which is a subclass of organic acids. Abnormally high levels of organic acids in the blood (organic acidemia), urine (organic aciduria), the brain, and other tissues lead to general metabolic acidosis. Acidosis typically occurs when arterial pH falls below 7.35. In infants with acidosis, the initial symptoms include poor feeding, vomiting, loss of appetite, weak muscle tone (hypotonia), and lack of energy (lethargy). These can progress to heart, liver, and kidney abnormalities, seizures, coma, and possibly death. These are also the characteristic symptoms of untreated MSUD. Many affected children with organic acidemias experience intellectual disability or delayed development. Flavouring ingredient for use in butter-type flavours. Found in banana, bread, cheeses, asparagus, beer and cocoa KEIO_ID M006 3-Methyl-2-oxobutanoic acid is a precursor of pantothenic acid in Escherichia coli.

   

Propionic acid

propionate;Methylacetic acid

C3H6O2 (74.0368)


Propionic acid (PA) is an organic acid. It exists a clear liquid with a pungent and unpleasant smell somewhat resembling body odor. Propionic acid (PA) is widely used as an antifungal agent in food. It is present naturally at low levels in dairy products and occurs ubiquitously, together with other short-chain fatty acids (SCFA), in the gastro-intestinal tract of humans and other mammals as an end-product of the microbial digestion of carbohydrates. The metabolism of propionic acid begins with its conversion to propionyl coenzyme A, the usual first step in the metabolism of carboxylic acids. Since propionic acid has three carbons, propionyl-CoA cannot directly enter either beta oxidation or the citric acid cycles. In most vertebrates, propionyl-CoA is carboxylated to D-methylmalonyl-CoA, which is isomerised to L-methylmalonyl-CoA. Propionic acid has significant physiological activity in animals. Propionic acid is irritant but produces no acute systemic effects and has no demonstrable genotoxic potential (PMID 1628870). The human skin is host of several species of bacteria known as Propionibacteria, which are named after their ability to produce propionic acid. The most notable one is the Cutibacterium acnes (formerly known as Propionibacterium acnes), which lives mainly in the sebaceous glands of the skin and is one of the principal causes of acne. Propionic aciduria is one of the most frequent organic acidurias, a disease that comprise many various disorders. The outcome of patients born with Propionic aciduria is poor intellectual development patterns, with 60\\\% having an IQ less than 75 and requiring special education. Successful liver and/or renal transplantations, in a few patients, have resulted in better quality of life but have not necessarily prevented neurological and various visceral complications. These results emphasize the need for permanent metabolic follow-up whatever the therapeutic strategy (PMID 15868474). Decreased early mortality, less severe symptoms at diagnosis, and more favorable short-term neurodevelopmental outcome were recorded in patients identified through expanded newborn screening. (PMID 16763906)↵ When propionic acid is infused directly into rodents brains, it produces hyperactivity, dystonia, social impairment, perseveration and brain changes (e.g., innate neuroinflammation, glutathione depletion) that may be used as a means to model autism in rats. Propionic acid is a metabolite of Bacteroides, Clostridium, Dialister, Megasphaera, Phascolarctobacterium, Propionibacterium, Propionigenum, Salmonella, Selenomonas and Veillonella (https://www.mdpi.com/2311-5637/3/2/21). Propionic acid, also known as propionate or ethanecarboxylic acid, is a member of the class of compounds known as carboxylic acids. Carboxylic acids are compounds containing a carboxylic acid group with the formula -C(=O)OH. Thus, propionic acid is considered to be a fatty acid lipid molecule. Propionic acid is soluble (in water) and a weakly acidic compound (based on its pKa). Propionic acid can be found in a number of food items such as celery stalks, burbot, sapodilla, and dock, which makes propionic acid a potential biomarker for the consumption of these food products. Propionic acid can be found primarily in most biofluids, including feces, saliva, blood, and urine, as well as throughout most human tissues. Propionic acid exists in all living species, ranging from bacteria to humans. In humans, propionic acid is involved in a couple of metabolic pathways, which include propanoate metabolism and vitamin K metabolism. Propionic acid is also involved in few metabolic disorders, which include malonic aciduria, malonyl-coa decarboxylase deficiency, and methylmalonic aciduria due to cobalamin-related disorders. Moreover, propionic acid is found to be associated with propionic acidemia. Propionic acid is a non-carcinogenic (not listed by IARC) potentially toxic compound.

   

Isovaleric acid

3-Methylbutyric acid: isopropyl-acetic acid

C5H10O2 (102.0681)


Isovaleric acid, is a natural fatty acid found in a wide variety of plants and essential oils. Isovaleric acid is clear colorless liquid that is sparingly soluble in water, but well soluble in most common organic solvents. It has been suggested that isovaleric acid from pilot whales, a species frequently consumed in the Faroe Islands, may be the unusual dietary factor in prolonged gestation in the population of the Faroe Islands. Previous studies suggested that was due to the high intake of n-3 polyunsaturated fatty acids has been, but fatty acid data for eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA) in blood lipids of Faroese and Norwegians was reviewed in terms of the type of fish eaten (mostly lean white fish with DHA much greater than EPA); the popular lean fish, thus, probably provides too little EPA to produce a marked effect on human biochemistry (PMID 2646392). Isovaleric acid is found to be associated with isovaleric acidemia, which is an inborn error of metabolism. Flavouring agent. Simple esters are used in flavourings. Constituent of hops, cheese etc.; an important component of cheese aroma and flavour CONFIDENCE standard compound; INTERNAL_ID 152 KEIO_ID I018 Isovaleric acid is a natural fatty acid and known to effect on neonatal death and possible Jamaican vomiting sickness in human. Isovaleric acid is a natural fatty acid and known to effect on neonatal death and possible Jamaican vomiting sickness in human.

   

Fusaric acid

Acid, 5-butyl-2-pyridinedicarboxylic

C10H13NO2 (179.0946)


D004791 - Enzyme Inhibitors > D019384 - Nucleic Acid Synthesis Inhibitors D018377 - Neurotransmitter Agents > D015259 - Dopamine Agents Fusaric acid is a potent dopamine β-hydroxylase inhibitor.

   

2-Oxovaleric acid

2-Ketopentanoic acid, sodium salt

C5H8O3 (116.0473)


2-Oxovaleric acid is an alpha-ketoacid is a metabolite usually found in human biofluids. Ketoacids have been known to play an important part in the metabolism of valine, leucine, isoleucine. 2-Oxovaleric acid presence has been determined in human blood serum and urine in numerous scientific documents, although its origin remains unclear. (PMID: 11482739, 9869358, 3235498). Acquisition and generation of the data is financially supported in part by CREST/JST. Isolated from Trigonella caerulea (sweet trefoil) 2-Oxovaleric acid is a keto acid that is found in human blood.

   

Dihydrolipoate

dl-Dihydro-α-6-thioctic acid

C8H16O2S2 (208.0592)


Dihydrolipoic acid is an organic compound that is the reduced form of lipoic acid. This carboxylic acid features a pair of thiol groups. It is optically active but only the R-enantiomer is biochemically significant. The lipoic acid/dihydrolipoic acid pair participate in a variety of biochemical transformations.( from Wiki). Inside the cell, alpha lipoic acid is readily reduced or broken down to dihydrolipoic acid. Dihydrolipoic acid is even more potent than alpha lipoic acid, neutralizing free radicals, preventing them from causing harm. It directly destroys damaging superoxide radicals, hydroperoxy radicals and hydroxyl radicals. It has been shown in vitro that dihydrolipoate (DL-6,8-dithioloctanoic acid) has antioxidant activity against microsomal lipid peroxidation.Dihydrolipoate is tested for its neuroprotective activity using models of hypoxic and excitotoxic neuronal damage in vitro and rodent models of cerebral ischemia in vivo. Dihydrolipoate, similarly to dimethylthiourea, is able to protect neurons against ischemic damage by diminishing the accumulation of reactive oxygen species within the cerebral tissue.(PMID: 1345759). Dihydrolipoic acid is an organic compound that is the reduced form of lipoic acid. This carboxylic acid features a pair of thiol groups. It is optically active but only the R-enantiomer is biochemically significant. The lipoic acid/dihydrolipoic acid pair participate in a variety of biochemical transformations.( from Wiki) D020011 - Protective Agents > D000975 - Antioxidants CONFIDENCE standard compound; INTERNAL_ID 162

   

Acetoacetate

Acetoacetic acid, calcium salt

C4H6O3 (102.0317)


Acetoacetic acid (AcAc) is a weak organic acid that can be produced in the human liver under certain conditions of poor metabolism leading to excessive fatty acid breakdown (diabetes mellitus leading to diabetic ketoacidosis). It is then partially converted into acetone by decarboxylation and excreted either in urine or through respiration. Persistent mild hyperketonemia is a common finding in newborns. Ketone bodies serve as an indispensable source of energy for extrahepatic tissues, especially the brain and lung of developing rats. Another important function of ketone bodies is to provide acetoacetyl-CoA and acetyl-CoA for synthesis of cholesterol, fatty acids, and complex lipids. During the early postnatal period, acetoacetate and beta-hydroxybutyrate are preferred over glucose as substrates for synthesis of phospholipids and sphingolipids in accord with requirements for brain growth and myelination. Thus, during the first two weeks of postnatal development, when the accumulation of cholesterol and phospholipids accelerates, the proportion of ketone bodies incorporated into these lipids increases. On the other hand, an increased proportion of ketone bodies are utilized for cerebroside synthesis during the period of active myelination. In the lung, AcAc serves better than glucose as a precursor for the synthesis of lung phospholipids. The synthesized lipids, particularly dipalmityl phosphatidylcholine, are incorporated into surfactant, and thus have a potential role in supplying adequate surfactant lipids to maintain lung function during the early days of life (PMID: 3884391). The acid is also present in the metabolism of those undergoing starvation or prolonged physical exertion as part of gluconeogenesis. When ketone bodies are measured by way of urine concentration, acetoacetic acid, along with beta-hydroxybutyric acid or acetone, is what is detected.

   

2-aminobutyrate

(2S)-2-aminobutanoic acid

C4H9NO2 (103.0633)


L-alpha-Aminobutyric acid, also known as (S)-2-aminobutanoic acid, homoalanine, 2-AABA, or alpha-Aminobutyric acid, is a member of the class of compounds known as L-alpha-amino acids. L-alpha-Amino acids are alpha amino acids which have the L-configuration of the alpha-carbon atom. Amino acids are organic compounds that contain amino (‚ÄìNH2) and carboxyl (‚ÄìCOOH) functional groups, along with a side chain (R group) specific to each amino acid. L-alpha-Aminobutyric acid is a non-proteogenic amino acid that can be found in the human kidney, in liver tissues, and in most biofluids or excreta (e.g. feces, breast milk, urine, and blood). Within the cell, L-alpha-aminobutyric acid is primarily located in the cytoplasm. alpha-Aminobutyric acid is biosynthesized by transamination of oxobutyrate, a metabolite in isoleucine biosynthesis. As a non-proteogenic amino acid, alpha-aminobutyric acid can be used by nonribosomal peptide synthases. One example of a nonribosomal peptide containing alpha-aminobutyric acid is ophthalmic acid, which was first isolated from calf lens. alpha-Aminobutyric acid is a non-essential amino acid that is primarily derived from the catabolism of methionine, threonine, and serine. High protein diets can result in significantly higher alpha-aminobutyrate levels in plasma (PMID: 26227325). alpha-Aminobutyric acid is elevated in the plasma of children with Reyes syndrome, tyrosinemia, homocystinuria, nonketotic hyperglycinemia, and ornithine transcarbamylase deficiency (PMID: 420125). alpha-Aminobutyric acid is one of the three isomers of aminobutyric acid. The two others are the neurotransmitter gamma-aminobutyric acid (GABA) and beta-aminobutyric acid (BABA) which is known for inducing plant disease resistance. alpha-Aminobutyric acid (AABA) is an isomer of the amino acid aminobutyric acid. It is a key intermediate in the biosynthesis of ophthalmic acid or ophthalmate. L-2-Aminobutanoic acid is found in common pea. α-Aminobutyric acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=80-60-4 (retrieved 2024-06-29) (CAS RN: 2835-81-6). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). H-Abu-OH, one of the three isomers of aminobutyric acid, is elevated in the plasma of children with with Reye's syndrome, tyrosinemia, homocystinuria, nonketotic hyperglycinemia, and ornithine transcarbamylase deficiency.

   

Citraconic acid

(2Z)-2-methylbut-2-enedioic acid

C5H6O4 (130.0266)


Citraconic acid, also known as 2-methylmaleate or methylmaleic acid, belongs to the class of organic compounds known as methyl-branched fatty acids. These are fatty acids with an acyl chain that has a methyl branch. Usually, they are saturated and contain only one or more methyl group. However, branches other than methyl may be present. Citraconic acid is a dicarboxylic acid consisting of maleic acid having a methyl substituent at the 2-position. Citraconic acid exists as a white solid. It is the cis-isomer of mesaconic acid and is one of the pyrocitric acids formed upon the heating of citric acid. Citraconic acid has been detected in the urine of both normal and fasting individuals (PMID: 6778884). Citraconic acid is also elevated in the urine of individuals with methylmalonic acidaemia who have suffered ketotic attacks (PMID: 116077). Altered serum levels of citraconic acid have been detected in patients with primary biliary cholangitis (PMID: 28400566). Mesaconic acid is one of several isomeric carboxylic acids obtained from citric acid. Is used as a fire retardant, recent studies revealed this acid is a competitive inhibitor of fumarate reduction. [HMDB] Citraconic acid belongs to the class of organic compounds known as methyl-branched fatty acids.

   

Tartaric acid

(2R,3R)-2,3-dihydroxybutanedioic acid

C4H6O6 (150.0164)


Tartaric acid is a white crystalline organic acid. It occurs naturally in many plants, particularly grapes and tamarinds, and is one of the main acids found in wine. It is added to other foods to give a sour taste, and is used as an antioxidant. Salts of tartaric acid are known as tartrates. It is a dihydroxy derivative of dicarboxylic acid. Tartaric acid is a muscle toxin, which works by inhibiting the production of malic acid, and in high doses causes paralysis and death. The minimum recorded fatal dose for a human is about 12 grams. In spite of that, it is included in many foods, especially sour-tasting sweets. As a food additive, tartaric acid is used as an antioxidant with E number E334, tartrates are other additives serving as antioxidants or emulsifiers. Naturally-occurring tartaric acid is chiral, meaning that it has molecules that are non-superimposable on their mirror-images. It is a useful raw material in organic chemistry for the synthesis of other chiral molecules. The naturally occurring form of the acid is L-(+)-tartaric acid or dextrotartaric acid. The mirror-image (enantiomeric) form, levotartaric acid or D-(-)-tartaric acid, and the achiral form, mesotartaric acid, can be made artificially. Tartarate is believed to play a role in inhibiting kidney stone formation. Most tartarate that is consumed by humans is metabolized by bacteria in the gastrointestinal tract -- primarily in the large instestine. Only about 15-20\\\\\\% of consumed tartaric acid is secreted in the urine unchanged. Tartaric acid is a biomarker for the consumption of wine and grapes (PMID:24507823). Tartaric acid is also a fungal metabolite, elevated levels in the urine (especially in children) may be due to the presence of yeast (in the gut or bladder). It can be produced by Agrobacterium, Nocardia, Rhizobium, Saccharomyces as well (PMID:7628083) (https://link.springer.com/article/10.1023/A:1005592104426). High levels of tartaric acid have been found in autistic children. In adults, tartaric acid may be due to the consumption of wine (https://www.greatplainslaboratory.com/articles-1/2015/11/13/candida-and-overgrowth-the-problem-bacteria-by-products) (PMID:15738524; PMID:24507823; PMID:7628083). Present in many fruits, wines and coffee. Acidulant for beverages, foods and pharmaceuticals,used to enhance natural and synthetic fruit flavours, especies in grape- and lime-flavoured drinks and candies. Firming agent, humectant. It is used in leavening systems including baking powders. Stabiliising agent for ground spices and cheeses to prevent discoloration. Chelating agent in fatty foods. Synergist with antioxidants, pH control agent in milk, jams and jellies, moisture-control agent. *Metatartaric* acid (a mixture of polyesters obtained by the controlled dehydration of (+)-tartaric acid, together with unchanged (+)-tartaric acid) is permitted in wine in UK (+)-Tartaric acid. CAS Common Chemistry. CAS, a division of the American Chemical Society, n.d. https://commonchemistry.cas.org/detail?cas_rn=87-69-4 (retrieved 2024-07-01) (CAS RN: 87-69-4). Licensed under the Attribution-Noncommercial 4.0 International License (CC BY-NC 4.0). DL-Tartaric acid is a non-racemic mixture of L- and D-tartaric acids with antioxidant activities[1][2]. L-Tartaric acid (L-(+)-Tartaric acid) is an endogenous metabolite. L-Tartaric acid is the primary nonfermentable soluble acid in grapes and the principal acid in wine. L-Tartaric acid can be used as a flavorant and antioxidant for a range of foods and beverages[1]. L-Tartaric acid (L-(+)-Tartaric acid) is an endogenous metabolite. L-Tartaric acid is the primary nonfermentable soluble acid in grapes and the principal acid in wine. L-Tartaric acid can be used as a flavorant and antioxidant for a range of foods and beverages[1].

   

trans-Aconitic acid

(1E)-prop-1-ene-1,2,3-tricarboxylic acid

C6H6O6 (174.0164)


trans-Aconitic acid, also known as trans-aconitate or (e)-aconitic acid, belongs to the class of organic compounds known as tricarboxylic acids and derivatives. These are carboxylic acids containing exactly three carboxyl groups. trans-Aconitic acid exists in all living species, ranging from bacteria to humans. trans-Aconitic acid is a dry, musty, and nut tasting compound. Outside of the human body, trans-aconitic acid has been detected, but not quantified in several different foods, such as garden tomato fruits, root vegetables, soy beans, and rices. trans-Aconitic acid is normally present in human urine, and it has been suggested that is present in larger amounts with Reyes syndrome and organic aciduria. trans-Aconitic acid in the urine is a biomarker for the consumption of soy products. trans-Aconitic acid is a substrate of enzyme trans-Aconitic acid 2-methyltransferase (EC2.1.1.144). Isolated from Asarum europaeum, from cane-sugar molasses, roasted chicory root, roasted malt barley, passion fruit, sorghum root and sugar beet. Flavouring agent used in fruit flavours and alcoholic beverages. Aconitic acid is an organic acid. The two isomers are cis-aconitic acid and trans-aconitic acid. The conjugate base of cis-aconitic acid, cis-aconitate is an intermediate in the isomerisation of citrate to isocitrate in the citric acid cycle. It is acted upon by aconitase. Trans-aconitate in the urine is a biomarker for the consumption of soy products. (E)-Aconitic acid is found in many foods, some of which are cereals and cereal products, rice, garden tomato (variety), and root vegetables. Acquisition and generation of the data is financially supported in part by CREST/JST. KEIO_ID A117 trans-Aconitic acid is present in normal human urine, and it has been suggested that is present in larger amounts with Reye's syndrome and organic aciduria. trans-Aconitic acid is a substrate of enzyme trans-aconitate 2-methyltransferase. trans-Aconitic acid is present in normal human urine, and it has been suggested that is present in larger amounts with Reye's syndrome and organic aciduria. trans-Aconitic acid is a substrate of enzyme trans-aconitate 2-methyltransferase.

   

Lactic acid

(R)-alpha-Hydroxypropionic acid

C3H6O3 (90.0317)


D-lactic acid, also known as D-lactate or D-2-hydroxypropanoic acid, belongs to alpha hydroxy acids and derivatives class of compounds. Those are organic compounds containing a carboxylic acid substituted with a hydroxyl group on the adjacent carbon. D-lactic acid is soluble (in water) and a weakly acidic compound (based on its pKa). D-lactic acid can be found in a number of food items such as tamarind, onion-family vegetables, allspice, and acerola, which makes D-lactic acid a potential biomarker for the consumption of these food products. D-lactic acid can be found primarily in blood, cerebrospinal fluid (CSF), and urine, as well as throughout most human tissues. D-lactic acid exists in all living species, ranging from bacteria to humans. In humans, D-lactic acid is involved in a couple of metabolic pathways, which include pyruvaldehyde degradation and pyruvate metabolism. D-lactic acid is also involved in several metabolic disorders, some of which include pyruvate kinase deficiency, pyruvate decarboxylase E1 component deficiency (PDHE1 deficiency), pyruvate dehydrogenase complex deficiency, and leigh syndrome. Moreover, D-lactic acid is found to be associated with diabetes mellitus type 2 and schizophrenia. D-lactic acid is a non-carcinogenic (not listed by IARC) potentially toxic compound. In animals, L-lactate is constantly produced from pyruvate via the enzyme lactate dehydrogenase (LDH) in a process of fermentation during normal metabolism and exercise. It does not increase in concentration until the rate of lactate production exceeds the rate of lactate removal, which is governed by a number of factors, including monocarboxylate transporters, concentration and isoform of LDH, and oxidative capacity of tissues. The concentration of blood lactate is usually 1–2 mmol/L at rest, but can rise to over 20 mmol/L during intense exertion and as high as 25 mmol/L afterward . Lactic acid is an organic acid. It is a chiral molecule, consisting of two optical isomers, L-lactic acid and D-lactic acid, with the L-isomer being the most common in living organisms. Lactic acid plays a role in several biochemical processes and is produced in the muscles during intense activity. D-Lactic acid is the end product of the enzyme glyoxalase II (or hydroxyacyl-glutathione hydrolase) (EC 3.1.2.6), which converts the intermediate substrate S-lactoyl-glutathione to reduced glutathione and D-lactate (OMIM: 138790). Lactic acid is a microbial metabolite found in Aerococcus, Bacillus, Carnobacterium, Corynebacterium, Enterococcus, Escherichia, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Rhizopus, Saccharomyces, Streptococcus, Tetragenococcus, Vagococcus and Weissella (PMID:26287368; PMID:26360870).

   

2-Hydroxyvaleric acid

alpha-Hydroxy-N-valeric acid

C5H10O3 (118.063)


2-Hydroxyvaleric acid is an organic acid present in human biofluids. Its presence in urine has been associated with lactic acidosis, which occurs in Succinic Acidemia (OMIM 600335), a syndrome of organic acidemia associated with congenital lactic acidosis and decreased NADH-cytochrome c reductase activity. 2-Hydroxyvaleric acid presence associated with lactic acidosis has also been found in Propionyl-CoA carboxylase deficiency (OMIM 253260), or Multiple carboxylase deficiency (MCD), an autosomal recessive metabolic disorder characterized primarily by cutaneous and neurologic abnormalities. (PMID: 9389332, 1790187, 3378323, 3383430, 7313494) [HMDB] 2-Hydroxyvaleric acid is an organic acid present in human biofluids. Its presence in urine has been associated with lactic acidosis, which occurs in Succinic Acidemia (OMIM 600335), a syndrome of organic acidemia associated with congenital lactic acidosis and decreased NADH-cytochrome c reductase activity. 2-Hydroxyvaleric acid presence associated with lactic acidosis has also been found in Propionyl-CoA carboxylase deficiency (OMIM 253260), or Multiple carboxylase deficiency (MCD), an autosomal recessive metabolic disorder characterized primarily by cutaneous and neurologic abnormalities. (PMID: 9389332, 1790187, 3378323, 3383430, 7313494).

   

Methyl dihydrojasmonate

Methyl 2-[(1R,2R)-3-oxo-2-pentylcyclopentyl]acetic acid

C13H22O3 (226.1569)


Methyl dihydrojasmonate is a flavouring ingredient.Methyl dihydrojasmonate is an ester and a diffusive aroma compound, with the smell vaguely similar to jasmin. In racemic mixtures the odour is floral and citrus while epimerized mixtures exhibit a dense fatty floral odour with odor recognition thresholds of 15 part per billion Flavouring ingredient [DFC] Methyl dihydrojasmonate is a fragrance ingredient with a jasmine-like odor, used in many fragrance mixtures[1]. Methyl dihydrojasmonate is a fragrance ingredient with a jasmine-like odor, used in many fragrance mixtures[1].

   

Oleacein

2-(3,4-Dihydroxyphenyl)ethyl (4Z)-4-formyl-3-(2-oxoethyl)hex-4-enoic acid

C17H20O6 (320.126)


Constituent of Olea europaea (olive)and is) also from Jasminum grandiflorum (Royal jasmine). Oleacein is found in many foods, some of which are green vegetables, tea, herbs and spices, and olive. Oleacein is found in fats and oils. Oleacein is a constituent of Olea europaea (olive). Also from Jasminum grandiflorum (Royal jasmine).

   

Aminooxyacetic acid

(O-Carboxymethyl)hydroxylamine

C2H5NO3 (91.0269)


D018377 - Neurotransmitter Agents > D018682 - GABA Agents D004791 - Enzyme Inhibitors

   

Disuccinimidyl suberate

1,1-((1,8-Dioxo-1,8-octanediyl)bis(oxy))bis-2,5-pyrrolidinedione

C16H20N2O8 (368.122)


   

2-Hydroxybutyric acid

(±)-2-hydroxybutyric acid

C4H8O3 (104.0473)


A hydroxybutyric acid having a single hydroxyl group located at position 2; urinary secretion of 2-hydroxybutyric acid is increased with alcohol ingestion or vigorous physical exercise and is associated with lactic acidosis and ketoacidosis in humans and diabetes in animals. (S)-2-Hydroxybutanoic acid is the S-enantiomer of?2-Hydroxybutanoic acid. 2-Hydroxybutanoic acid, a coproduct of protein metabolism, is an insulin resistance (IR) biomarker[1].

   

3-Methyl-2-oxovaleric acid

(3S)-3-Methyl-2-oxopentanoic acid

C6H10O3 (130.063)


A 2-oxo monocarboxylic acid that is valeric acid carrying oxo- and methyl substituents at C-2 and C-3, respectively. An alpha-keto acid analogue and metabolite of isoleucine in man, animals and bacteria. Used as a clinical marker for maple syrup urine disease (MSUD). 3-Methyl-2-oxovaleric acid is a neurotoxin, an acidogen, and a metabotoxin, and also an abnormal metabolite that arises from the incomplete breakdown of branched-chain amino acids.

   

α-Aminoadipic acid

DL-α-Aminoadipic acid

C6H11NO4 (161.0688)


An optically active form of 2-aminoadipic acid having D-configuration. The L-enantiomer of 2-aminoadipic acid. D018377 - Neurotransmitter Agents > D018683 - Excitatory Amino Acid Agents > D018691 - Excitatory Amino Acid Antagonists Acquisition and generation of the data is financially supported in part by CREST/JST. CONFIDENCE standard compound; ML_ID 9 Aminoadipic acid is an intermediate in the metabolism of lysine and saccharopine. Aminoadipic acid is an intermediate in the metabolism of lysine and saccharopine.

   

2-Methylglutaric acid

(2R)-2-Methylpentanedioic acid

C6H10O4 (146.0579)


An alpha,omega-dicarboxylic acid that is glutaric acid substituted at position 2 by a methyl group. Acquisition and generation of the data is financially supported in part by CREST/JST. 2-Methylpentanedioic acid is a metabolite of succinic acid, a citric acid cycle intermediate.

   

Hippuric acid

2-BENZAMIDOACETIC ACID

C9H9NO3 (179.0582)


C254 - Anti-Infective Agent > C255 - Urinary Anti-Infective Agent An N-acylglycine in which the acyl group is specified as benzoyl. MS2 deconvoluted using MS2Dec from all ion fragmentation data, MetaboLights identifier MTBLS1040; QIAFMBKCNZACKA-UHFFFAOYSA-N_STSL_0191_Hippuric acid_2000fmol_180831_S2_L02M02_62; Spectrum acquired as described in Naz et al 2017 PMID 28641411. Preparation and submission to MassBank of North America by Chaleckis R. and Tada I. MS2 deconvoluted using CorrDec from all ion fragmentation data, MetaboLights identifier MTBLS1040; Spectrum acquired as described in Naz et al 2017 PMID 28641411. Preparation and submission to MassBank of North America by Chaleckis R. and Tada I. relative retention time with respect to 9-anthracene Carboxylic Acid is 0.317 relative retention time with respect to 9-anthracene Carboxylic Acid is 0.318 relative retention time with respect to 9-anthracene Carboxylic Acid is 0.315 Hippuric Acid (2-Benzamidoacetic acid), an acyl glycine produced by the conjugation of benzoic acid and glycine, is a normal component in urine as a metabolite of aromatic compounds from food. Hippuric Acid (2-Benzamidoacetic acid), an acyl glycine produced by the conjugation of benzoic acid and glycine, is a normal component in urine as a metabolite of aromatic compounds from food.

   

lipoamide

5-(1,2-dithiolan-3-yl)pentanamide

C8H15NOS2 (205.0595)


A monocarboxylic acid amide resulting from the formal condensation of the carboxy group of lipoic acid with ammonia.

   

3-phenyllactic acid

DL-3-Phenyllactic acid

C9H10O3 (166.063)


A 2-hydroxy monocarboxylic acid that is lactic acid in which one of the methyl hydrogens is substituted by a phenyl group. DL-3-Phenyllactic acid is a broad-spectrum antimicrobial compound. DL-3-Phenyllactic acid is a broad-spectrum antimicrobial compound.

   

D-α-HYDROXYISOVALERIC ACID

(R)-2-hydroxy-3-methylbutanoic acid

C5H10O3 (118.063)


   

(S)-2-Phenylpropanoic acid

(S)-(+)-2-Phenylpropionic acid

C9H10O2 (150.0681)


   

FA 5:1;O2

(4S)-4-hydroxy-2-ketovaleric acid;(4S)-4-hydroxy-2-oxovaleric acid;(S)-4-hydroxy-2-ketopentanoic acid

C5H8O4 (132.0423)


D018377 - Neurotransmitter Agents > D018847 - Opioid Peptides D018377 - Neurotransmitter Agents > D004399 - Dynorphins 2-Methylsuccinic acid is a normal metabolite in human fluids and the main biochemical measurable features in ethylmalonic encephalopathy. Ethylmalonic acid is non-carcinogenic potentially toxic and associated with anorexia nervosa and malonyl-CoA decarboxylase deficiency.

   

3,4-DHPEA-EA

Methyl (2R,4S)-4-{2-[2-(3,4-dihydroxyphenyl)ethoxy]-2-oxoethyl}-3-ethylidene-2-hydroxy-3,4-dihydro-2H-pyran-5-carboxylic acid

C19H22O8 (378.1315)


3,4-DHPEA-EA is the major form of the oleuropein-aglycone. 3,4-DHPEA-EA is found in olive. 3,4-DHPEA-EA is found in olive. 3,4-DHPEA-EA is the major form of the oleuropein-aglycone