2,2-Diphenyl-1-picrylhydrazil radical scavenging activity of extracts from roots and leaves of Searsia burchellii
Searsia burchellii finds therapeutic applications in traditional medicine. Methanolic extracts, hexane, chloroform, ethyl acetate and methanol/water fractions of methanolic extracts and water extracts were obtained separately from the roots and leaves of Searsia burchellii by the combination of maceration, hot solvent extraction and solvent-solvent partition techniques. These extracts were evaluated for their antioxidant activity using 2,2- diphenyl-1-picrylhydrazil radical scavenging assay (DPPH). The extracts from roots and their fractions showed radical scavenging activity ranging from 6.60±4.50 to 63.27±1.93% at various concentrations. Similarly, the extracts from leaves and their fractions showed radical scavenging activity ranging from 3.32±0.95 to 64.91±0.15% at various concentrations. Ascorbic acid served as positive control which showed radical scavenging activity ranging from 53.62±2.80 to 60.82±0.62% at various concentrations. The IC50 values of these extracts and fractions were found to be < 200 to > 3000 µg/mL. The IC50 value of ascorbic acid was found to be <200 µg/mL. From this study, we concluded that extracts and their fractions from S. burchellii showed promising radical scavenging activity.