Free Radical Scavenging Activity of Methanolic Extract of Calotropis procera Roots in EthanolInduced Oxidative Stress Male Wistar Rats

The generation of free reactive radicals and the biochemical strategy underlying their mopping are paramount to healthy cellular activities. The scavenging activity of the methanolic extract of Calotropis procera roots on the hydroxyl radicals, nitric oxide and hydrogen peroxide was investigated in ethanol-induced oxidative stressed male Wistar rats and a concentration dependent percentage radical scavenging activity was observed against these free radicals with IC50 of 54.9 mg/ml, 54.2 mg/ml and 37.3 mg/ml respectively. The rats were treated with 250 mg/ml and 500 mg/ml per kg body weight after 5-6 hours of inducing oxidative stress. The blood serum was analysed for the activities of superoxide dismutase (SOD) and catalase (CAT). A positive in vivo modulatory effect on the catalytic turnover rate of SOD and CAT was observed. SOD activity reduced from 0.057 +/- 0.003 U/ml in induced oxidative stress rats to 0.023 +/- 0.003 U/ml when treated with 250 mg/ml/kg root extract and 0.014 +/- 0.003 U/ml when treated with 500mg/ml root extract, a value which was not statistically different (p< 0.05) from the control. In addition, the CAT activity reduced from 77000 +/- 140 ae molmin-1 in induced oxidative stress rats to 37000 +/- 130 ae molmin-1 when treated with 250 mg/ml/kg roots extract, a value which was not statistically different (p< 0.05) from the control, and there was a further reduction in the CAT activity when treated with 500 mg/ml/kg root extract. Hence, the methanolic extract of the root of Calotropis procera may serve as a good nonenzymatic radical scavenger. These results have shown a concentration dependent radical scavenging activity of the methanolic extract of the roots of Calotropis procera against reactive oxygen and nitrogen free radicals with positive modulatory action in the biochemical rescue of plasma antioxidant enzymes in scavenging these deleterious free radicals, which are constantly generated in aerobic cellular activities.