Antibacterial and antioxidant activity of different extracts obtained from Withania somnifera (Ashwagandha)

Abstract

Ashwagandha (W. somnifera) is widely known as the queen of Indian Ayurveda. The objective of this study was to determine the antioxidant and antibacterial activity of the different parts of the Ashwagandha.  The antioxidant activity of different extracts from different parts of Ashwagandha was determined using DPPH free radical scavenging method. Ashwaghanda root inhabiting bacteria was isolated using pour-plate technique. The agar well method and filter paper method were followed to assess the antibacterial activity of the extracts. Ethanol-water extracts (1:1 v/v) gave higher yield of extractable matter than methanol extracts. The antioxidant activity of fresh root extract was significantly higher than other parts of the plant (stem and leaves) as well as the plant material bought from open market. The minimal inhibitory concentration (MIC) values of Ethanol-water extract against MRSA, Candida Sp. and Salmonella Sp. were >256 mg/L. The commensal bacteria (Bacilli Sp.) inhabiting Ashwagandha roots displayed mild antibacterial activity against pathogenic P. aeruginosa. Keywords:  Ashwaghanda, commensal bacteria, Antibacterial activity, Antioxidant activity, Crude extracts