In vitro antimicrobial activities of different fractions of Swertia chirata ethanolic extract

The aim of the present study was to evaluate the in vitro antimicrobial activity of pet-ether, dichloromethane and methanol fractions of Swertia chirata (Family: Gentianaceae) ethanolic extract. Disc diffusion technique and food poison method were used for antibacterial and antifungal activity, respectively. Dichloromethane fraction from both leaf and stem showed significant antimicrobial activities against some Gram-positive and Gram-negative bacteria and mild to moderate activity against some fungi. A large zone of inhibition was observed (19 mm) against Staphylococcus aureus. Test materials at a concentration of 400 microg disc(-1) were used to evaluate the antimicrobial activity while Kanamycin at a concentration of 30 microg disc(-1) was used as positive control in this study. Among different fractions, dichloromethane fraction showed significant antimicrobial activity against Gram-positive, Gram-negative and fungi. The most significant antimicrobial activity was seen against Staphylococcus aureus which reflects it potentiality to be used in skin infections.