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DRI DIETARY REFERENCE INTAKES FOR Vitamin C, Vitamin E, Selenium, and Carotenoids
FIGURE 5-1 Chemical structure of ascorbic acid.
volves either monooxygenase or dioxygenase activities (Levine et al., 1996b).
As a cofactor for hydroxylase and oxygenase metalloenzymes, ascorbic acid is believed to work by reducing the active metal site, resulting in reactivation of the metal-enzyme complex, or by acting as a co-substrate involved in the reduction of molecular oxygen. The