Abstract

In the present study antioxidant and antimicrobial activities of extracts from leaves and flowers of local Akk (Calotropis procera) were examined. The antioxidant components were extracted using 80% aqueous methanol, 80% aqueous ethanol and 80% aqueous acetone solvents. The antioxidant yield from leaves and flowers of C. procera ranged from 8.48 to 14.07 g/100 g dry weight. The total phenolic and flavanoid content were considerable with total phenolic yields (expressed as gallic acid equivalents) reported in the range of 0.11 to 0.32 g/100 g dry weight, and total flavonoid content (expressed as catechin equivalents) reported in the range 0.01 to 0.10 g/100 g dry weight. C. proceraextracts exhibited a reasonable DPPH radical scavenging activity (IC50 8.81 to 37.30 mg/ml) and inhibition of linoleic acid peroxidation (13.63 to 41.53%). Antimicrobial activity of the extracts was evaluated against selected strains of bacteria and pathogenic fungi. The present results revealed that among the samples analyzed, maximum antioxidant and antimicrobial activities were exhibited by 80% ethanol extract of leaves whereas lowest by 80% acetone extract of flowers. From the results of the present investigation, it could be concluded that C. procera extracts can be explored as a potential source for isolation of antioxidant and antimicrobial agents. However, an appropriate solvent extraction system should be used to recover potent antioxidant components from C. procera.

Key words: Akk extracts, solvent extraction, phenolic components, antioxidant assays, antimicrobial potential, microorganisms.