In vitro antioxidant activities of four medicinal plants on the basis of DPPH free radical scavenging.

The present research investigation was aimed at the evaluation of antioxidant activities of methanolic (70%) extracts of whole plant of Pentanema vestitum and fruits of Pistacia integerrima, Withiana somniferra and Withiana coagulans on scavenging of 2, 2-diphenyl-2-picrylhydrazyl (DPPH) free radical. The rank of order of free antioxidant activity of the selected plants was; P. integerrima > P. vestitum > W. somniferra > W. coagulans as compared to standard Ascorbic acid. P. integerrima showed significantly higher activity at all concentrations as compared to Ascorbic acid at P<0.05. The percent inhibition caused by P. integerrima at lowest concentration (40 ppm) was 68.16±0.5 and that of Ascorbic acid was 62.00±0.5. The IC50 value of P. integerrima was 5.75ppm as compared to ascorbic acid having 15.09 ppm. The percent inhibition at all concentrations caused by P. vestitum was not significantly different from Ascorbic acid at P<0.05. The IC50 value of P. vestitum was 13.00ppm and that of Ascorbic acid was 15.09 ppm. The percent inhibitions caused by W. somniferra (IC50=46.85 ppm) and W. coagulans (IC50=84.40 ppm) were most significantly lower than Ascorbic acid at P<0.05. It is inferred from the current study that the methanolic (70%) extracts of the P. integerrima and P. vestitum could be used in preparation of potent antioxidant drugs.