E as in Vivo Lipid Antioxidant

Knowledge of olefin peroxidation has developed extensively (Lundberg, 1961) because it is widely recognized that this free radical chain reaction is a basic mechanism in many deteriorative reactions. 

This chain reaction can be effectively inhibited by antioxidants of many classes, of which the polyphenolic are of primary importance. Further, a simple hydrogen abstraction reaction is the most important mechanism for breaking the reaction chain and inhibiting peroxidation (Uri, 1961). 

This chemical knowledge compels us to accept the fact that animals that contain the very oxygen-labile polyunsaturated lipids require lipid antioxidants. This biological essential of a lipid antioxidant is mainly filled by vitamin E. Therefore, the chemical basis of vitamin E function is its reactions with free radical intermediates of lipid peroxidation and with the peroxides. 

Oxidation products of a-tocopherol (I) a-tooopherol (II) a-tocopheryl-qiiinono, main product from lipid peroxidation (III) a-tocopherylhydroquinone (IV) 6-exomethylene tocopher-6-one, main product from radiation (V) and (VI) 2- (3-hydroxy-3-methyl-6-carboxy) -pentyl-3,5,6-trimethylbenzoquinone and its 

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