ANTIOXIDANT ACTIVITY OF ALLICIN, AN ACTIVE PRINCIPLE IN GARLIC

Garlic has been claimed to be effective against diseases, in the patho physiology of which oxygen free radicals (OFRs) have been implicated. Effectiveness of garlic could be due to its ability to scavenge OFRs. However, its antioxidant activity is not known. We investigated the ab ility of allicin (active ingredient of garlic) contained in the commer cial preparation Garlicin to scavenge hydroxyl radicals (. OH) using h igh pressure liquid chromatographic (HPLC) method. . OH was generated by photolysis of H2O2 (1.25-10 mu moles/ml) with ultraviolet light and was trapped with salicylic acid which is hydroxylated to produce . OH adduct products 2,3- and 2,5-dihydroxybenzoic acid (DHBA). H2O2 produ ced a concentration-dependent . OH as estimated by . OH adduct product s 2,3-DHBA and 2,5-DHBA. Allicin equivalent in Garlicin (1.8, 3.6, 7.2 , 14.4, 21.6, 28.8 and 36 mu g) produced concentration-dependent decre ases in the formation of 2,3-DHBA and 2,5-DHBA. The inhibition of form ation of 2,3-DHBA and 2,5-DHBA with 1.8 mu g/ml was 32.36% and 43.2% r espectively while with 36.0 mu g/ml the inhibition was approximately 9 4.0% and 90.0% respectively. The decrease in . OH adduct products was due to scavenging of . OH and not by scavenging of formed . OH adduct products. Allicin prevented the lipid peroxidation of liver homogenate in a concentration-dependent manner. These results suggest that allic in scavenges . OH and Garlicin has antioxidant activity.