Antibacterial potential of Withania somnifera L. against human pathogenic bacteria

Abstract

The present study was conducted to evaluate the antibacterial activity of chloroform, acetone, methanolic, and ethanolic crude extracts of stem, leaves, and roots of Withania somnifera. It was observed that acetone extracts was the most effective followed by methanolic and ethanolic extracts for all the test organisms used. It was observed that acetone extracts were the most effective in inhibiting the growth of all the pathogenic bacteria used. The zone of inhibition was maximum with acetone extracts ranging between 38 and 10 mm, followed by methanolic extracts ranging between 28 and 10 mm and ethanolic extracts ranging between 25 and 8 mm, respectively. However, Klebsiella pneumoniae and methicillin-resistant Staphylococcus aureus (MRSA) did not respond to root extracts of both methanolic and ethanolic extracts. The chloroform extracts of stem and leaves showed significant activity against all pathogens with inhibition zone between 20 and 8 mm. The results indicate that acetone, methanolic, and ethanolic extracts of W. somniferamight be exploited as natural drug for the treatment of several infectious diseases caused by these organisms. Key words: Withania somnifera, acetone extracts, methanolic extract, ethanolic extract, antimicrobial activity, inhibition zone.