Abstract

ANTIMICROBIAL SCREENING OF DIFFERENT SOLVENT EXTRACTS OF AN ENDANGERED MEDICINAL PLANT, STRYCHNOS WALLICHIANA STEUD EX DC

I. Veera Kishore, R. Ragalatha, N. Krishna, M. Vijayalakshmi and K. Mallikarjuna*

Abstract

Strychnos wallichiana is very important medicinal plant for phytochemicals and other biologically active molecules. In the present work, N-hexane, chloroform, ethyl acetate and methanol extracts of stem, leaf, root and fruit coat of S. wallichiana were screened against six microbes like Candida albicans, Staphylococcus aureus, Klebsiella pneumoniae, Bacillus subtilis, Bacillus cereus, and E. coli and fungus Candida albicans by agar well diffusion method. Among four solvent leaf extracts, chloroform and ethyl acetate extracts exhibited significant activity in terms high zone of inhibition (0.8 to 1.3cm). High zone of inhibition and less zone of inhibition was formed by leaf ethyl acetate and methanol extracts against Candida albicans and S.aureus. The leaf methanol formed high zone of inhibition against K.pneumoniae. Moderate activity was displayed by leaf methanol, ethyl acetate, chloroform, and n-hexane extracts against B. subtilis and B. cereus. Good activity against E.coli was observed with leaf methanol and ethyl acetate extracts. Moderate antimicrobial activity with range of zone of inhibition from 0.6 to 1.4 cm was exhibited by stem ethyl acetate extracts. High zone of inhibition (2cm) was formed by stem chloroform extract against B.cereus while other extracts displayed no activity. Whereas E.coli exhibited good zone of inhibition in all extracts except in n-hexane. When compared with leaf or stem extracts, the fruit coat extract exhibited poor activity against all treated microbes.

Keywords: Strychnos wallichiana treated microbes.