XANTHINE-OXIDASE INHIBITORY ACTIVITY OF CAFFEIC, CHLOROGENIC AND FERULIC ACIDS

The in vitro effects of caffeic, chlorogenic, and ferulic acids on rat liver and purified milk xanthine oxidase activity was investigated an d compared with allopurinol, a well known xanthine oxidase inhibitor. The IC50 of caffeic, chlorogenic, and ferulic acid as well as allopuri nol was 2.1 X 10(-5) M, 2.5 X 10(-5) M, 2.1 X 10(5) M, and 1.5 X 10(-5 ) M respectively for rat liver xanthine oxidase. The IC50 of caffeic, chlorogenic, ferulic acid, and allopurinol was 3.8 X 10(-5)M, 2.6 X 10 (-5) M, 2.2 X 10(-5) M and 1.2 X 10(-5) M, respectively, for purified milk xanthine oxidase. The caffeic acid, chlorogenic acid, and ferulic acid inhibit both rat liver xanthine oxidase and purified milk xanthi ne oxidase in dose dependent manner.