Classification Term: 170050
醌和氢醌脂质 (ontology term: 340b288f9431af2e2b5844be66af5ea9)
found 3 associated metabolites at sub_class
metabolite taxonomy ontology rank level.
Ancestor: 醌类
Child Taxonomies: There is no child term of current ontology term.
Delta-CEHC
delta-CEHC, also known as δ-cehc, belongs to the class of organic compounds known as 1-benzopyrans. These are organic aromatic compounds that 1-benzopyran, a bicyclic compound made up of a benzene ring fused to a pyran, so that the oxygen atom is at the 1-position. Based on a literature review very few articles have been published on delta-CEHC.
Gamma-tocopherol/beta-tocopherol
beta-Tocopherol is an antioxidant which is synthesized by photosynthetic organisms and plays an important role in human and animal nutrition. beta-Tocopherols can be oxidized in dry CH2Cl2 or CH3CN by one electron to form cation radicals that deprotonate to form the neutral phenoxyl radicals, which are then immediately further oxidized by one electron to the phenoxonium cations (an ECE electrochemical mechanism, where E signifies an electron transfer and C represents a chemical step, with the electrochemical mechanism having been determined by in situ spectroscopic analysis). The phenoxonium cation of beta-tocopherol is stable for several minutes (PMID: 16771430). beta-Tocopherol has been identified in the human placenta (PMID: 32033212). Beta-tocopherol is a tocopherol in which the chroman-6-ol core is substituted by methyl groups at positions 5 and 8. While it is found in low concentrations in many vegetable oils, only cottonseed oil contains significant amounts. It has a role as a plant metabolite and a food component. It is a vitamin E and a tocopherol. beta-Tocopherol is a natural product found in Trachycarpus fortunei, Crataegus monogyna, and other organisms with data available. A natural tocopherol with less antioxidant activity than alpha-tocopherol. It exhibits antioxidant activity by virtue of the phenolic hydrogen on the 2H-1-benzopyran-6-ol nucleus. As in GAMMA-TOCOPHEROL, it also has three methyl groups on the 6-chromanol nucleus but at different sites. A tocopherol in which the chroman-6-ol core is substituted by methyl groups at positions 5 and 8. While it is found in low concentrations in many vegetable oils, only cottonseed oil contains significant amounts. (rel)-β-Tocopherol is a relative configuration of β-Tocopherol.(±)-β-Tocopherol is a lipid-soluble form of vitamin E with antioxidant activity. β-Tocopherol can inhibit tyrosinase activity and melanin synthesis. β-Tocopherol also can prevent the inhibition of cell growth and of PKC activity caused by d-alpha-tocopherol[1]. β-Tocopherol is an analogue of vitamin E, exhibits antioxidant properties. β-Tocopherol can inhibit tyrosinase activity and melanin synthesis. β-Tocopherol also can prevent the inhibition of cell growth and of PKC activity caused by d-alpha-tocopherol[1][2][3]. β-Tocopherol is an analogue of vitamin E, exhibits antioxidant properties. β-Tocopherol can inhibit tyrosinase activity and melanin synthesis. β-Tocopherol also can prevent the inhibition of cell growth and of PKC activity caused by d-alpha-tocopherol[1][2][3].
Alpha-tocopherol
α-Tocopherol (alpha-tocopherol) is a type of vitamin E. Its E number is "E307". Vitamin E exists in eight different forms, four tocopherols and four tocotrienols. All feature a chromane ring, with a hydroxyl group that can donate a hydrogen atom to reduce free radicals and a hydrophobic side chain which allows for penetration into biological membranes. Compared to the others, α-tocopherol is preferentially absorbed and accumulated in humans. Vitamin E is found in a variety of tissues, being lipid-soluble, and taken up by the body in a wide variety of ways. The most prevalent form, α-tocopherol, is involved in molecular, cellular, biochemical processes closely related to overall lipoprotein and lipid homeostasis. Ongoing research is believed to be "critical for manipulation of vitamin E homeostasis in a variety of oxidative stress-related disease conditions in humans."[2] One of these disease conditions is the α-tocopherol role in the use by malaria parasites to protect themselves from the highly oxidative environment in erythrocytes.[3] Stereoisomers α-Tocopherol has three stereocenters, so it is a chiral molecule.[4] The eight stereoisomers of α-tocopherol differ in the configuration of these stereocenters. RRR-α-tocopherol is the natural one.[5] The older name of RRR-α-tocopherol is d-α-tocopherol, but this d/l naming should no longer be used, because whether l-α-tocopherol should mean SSS enantiomer or the SRR diastereomer is not clear, from historical reasons. The SRR may be named 2-epi-α-tocopherol, the diastereomeric mixture of RRR-α-tocopherol and 2-epi-α-tocopherol may be called 2-ambo-α-tocopherol (formerly named dl-α-tocopherol). The mixture of all eight diastereomers is called all-rac-α-tocopherol.[6] One IU of tocopherol is defined as 2⁄3 milligram of RRR-α-tocopherol (formerly named d-α-tocopherol). 1 IU is also defined as 0.9 mg of an equal mix of the eight stereoisomers, which is a racemic mixture, all-rac-α-tocopheryl acetate. This mix of stereoisomers is often called dl-α-tocopheryl acetate.[7] Starting with May 2016, the IU unit is made obsolete, such that 1 mg of "Vitamin E" is 1 mg of d-alpha-tocopherol or 2 mg of dl-alpha-tocopherol.[8] α-Vitamin E ((+)-α-Tocopherol), a naturally occurring vitamin E form, is a potent antioxidant[1][2]. α-Vitamin E ((+)-α-Tocopherol), a naturally occurring vitamin E form, is a potent antioxidant[1][2].