Antioxidant activity of the methanol fraction of Pluchea indica root extract.

Studies were carried out to evaluate the influence of the methanol fraction of Pluchea indica Less root extract (PIRE), the dual inhibitors (BW 755C and phenidone) and vitamin on both in vivo and in vitro free radical-scavenging activities, CCl(4)-induced lipid peroxidation and the metabolism of arachidonic acid by lipoxygenase. PIRE produced significant antiinflammatory activity against glucose oxidase-induced paw oedema (in vivo), inhibited hydroxyl radical and superoxide generation, lysis of erythrocytes induced by hydrogen peroxide, CCl(4)-induced lipid peroxidation and also dioxygenase activity of lipoxygenase (both in the presence and absence of hydrogen peroxide). Significantly higher free radical-scavenging activity was observed with BW 755C and phenidone compared with PIRE. However, both BW 755C and phenidone stimulated hydroxyl radical generation compared with the observed inhibitory effects of PIRE and vitamin E. Copyright 2002 John Wiley & Sons, Ltd.