ascor brands

Molecular formula: C6H8O6

In humans, an exogenous source of ascorbic acid is required for collagen formation and tissue repair by acting as a cofactor in the posttranslational formation of 4-hydroxyproline in -Xaa-Pro-Gly- sequences in collagens and other proteins. Ascorbic acid is reversibly oxidized to dehydroascorbic acid in the body. These two forms of the vitamin are believed to be important in oxidation-reduction reactions. The vitamin is involved in tyrosine metabolism, conversion of folic acid to folinic acid, carbohydrate metabolism, synthesis of lipids and proteins, iron metabolism, resistance to infections, and cellular respiration. Ascorbic Acid reducing potential and conversion to AFR (ascorbate free radical) are key to its biological activity, including its free radical scavenging and its relationship to the oxidation of transition metals such as iron and copper at enzyme active sites and in food. Vitamin C is known to be an electron donor for eight human enzymes. Three participate in collagen hydroxylation; two in carnitine biosynthesis; and three in hormone and amino acid biosynthesis. The three enzymes that participate in hormone and amino acid biosynthesis are dopamine-beta-hydroxylase, necessary for the biosynthesis of the catecholamines norepinephrine and epinephrine; peptidyl-glycine monooxygenase, necessary for amidation of peptide hormones; and 4-hydroxyphenylpyruvatedioxygenase, involved in tyrosine metabolism. Ascorbate's action with these enzymes involves either monooxygenase or dioxygenase activities. 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 best known of these reactions is the posttranslational hydroxylation of peptide-bound proline and lysine residues during formation of mature collagen. In these reactions, ascorbate is believed to reactivate the enzymes by reducing the metal sites of prolyl (iron) and lysyl (copper) hydroxylases. Evidence also suggests that ascorbate plays a role in or influences collagen gene expression, cellular procollagen secretion, and the biosynthesis of other connective tissue components besides collagen, including elastin, fibronectin, proteoglycans, bone matrix, and elastin-associated fibrillin. The primary physical symptoms of ascorbic acid's clinical deficiency disease, scurvy, which involves deterioration of elastic tissue, illustrate the important role of ascorbate in connective tissue synthesis. For more Mechanism of Action (Complete) data for L-Ascorbic Acid (11 total), please visit the HSDB record page.

Source: PubChem (NCBI) · compound 54670067