SAPONINS FROM SOLANUM ANGUIVI LAM. FRUIT EXHIBIT IN VITRO AND IN VIVO ANTIOXIDANT ACTIVITIES IN ALLOXAN-INDUCED OXIDATIVE STRESS

摘要

Objective: To evaluate the antioxidant and radical scavenging activities of saponins from Solanum anguivi fruit (SAGU) and its possible effect on oxidative status of rat exposed to alloxan-induced diabetes. Methods: Antioxidant activity of SAGU was assayed by using 2,2'-azino-bis3-ethylbenzothiazoline-6-sulphonic acid (ABTS), reducing power, iron chelation and ability to inhibit lipid peroxidation in both liver and brain homogenates of rats. Also, the effect of SAGU on MDA level, an indicator of lipid peroxidation and activity of superoxide dismutase (SOD) and catalase (CAT) were determined in heart and kidney of rat exposed to alloxan (150mg/kg) for 21 days. Results: SAGU exhibited potent and concentration dependent free radical-scavenging activity (IC50/ABTS = 290.12 ± 1.34μg/ml). Reductive and iron chelation abilities also increase with increase in SAGU concentration. SAGU also inhibited peroxidation of hepatic and cerebral lipids subjected to iron oxidative assault. In addition, SAGU significantly (P<0.05) protected against lipid peroxidation induced by alloxan as well as restored the level of SOD and CAT in both heart and kidney of alloxan-treated rats. Conclusions: Taking together, our results suggest that saponins from the fruits of Solanum anguivi are potent antioxidant that can be useful not only in pharmaceutical and food industry, but also in the management of diabetes.