OXYRADICAL SCAVENGING EFFECTS OF DEHYDROASCORBATE

Dehydroascorbate (DHA) has been shown to possess vitamin C like activi ties as well as to protect the lens against oxidative stress and catar act formation. The results presented here suggest that some of the ben eficial effects of DHA can be attributed to its property of undergoing peroxidative decarboxylation and of O-2(radical anion) scavenging. In cubation of 1-C-14-DHA with peroxide at physiological pH has been foun d to liberate (CO2)-C-14 in quantitative yields, with recovery of 79-9 4%. The recovery increases with the increase in the amount of DHA used . Its O-2(radical anion) scavenging activity was apparent by inhibitio n of O-2(radical anion) dependent reduction of ferricytochrome c and n itroblue tetrazolium. The authenticity of the latter mechanism was pro ved by inhibition of the O-2(radical anion) dependent reactions also b y superoxide dismutase.