Abstract
L-Ascorbic acid (AsA) is an important antioxidant in food and biological systems, but it is unstable under various oxidative conditions, resulting in its rapid degradation. Therefore, the development of many stable AsA derivatives has been attempted. Among them, ascorbic acid 2-glucoside (AA-2G) has been approved by the Japanese Government as a quasi-drug principal ingredient in skin care and a food additive and it has been used widely in cosmetics and health foods in Japan. AA-2G is a provitamin C agent that exhibits vitamin C activity in vitro and in vivo after its enzymatic hydrolysis to AsA by α-glucosidase. 6-O-Acyl-2-O-α-D-glucopyranosyl-L-ascorbic acids having a straight-acyl chain of varying length from C4 to C18 (6-sAcyl-AA-2G) and a branched-acyl chain of varying length from C6 to C16 (6-bAcyl-AA-2G) are lipophilic stable AsA derivatives for improving the bioavailability of AA-2G. 6-sAcyl-AA-2G and 6-bAcyl-AA-2G exert usually known vitamin C functions efficiently in vitro and in vivo. Recently, AsA derivatives immobilized on a resin to let proteins recognize characteristic chemical structures of AsA have also been synthesized as new tools for identifying target proteins of AsA. In this mini review, the author presents researches using these AsA derivatives in applied fields from basic fields.
