Antimicrobial activity ofTerminalia bellerica

Abstract

The antimicrobial activity of crude and methanol extract ofTerminalia bellerica dry fruit was tested by disc diffusion method, against 9 human microbial pathogens. Crude aqueous extract of dry fruit at 4 mg concentration showed zone of inhibition ranging from 15.5-28.0 mm.S. aureus was found to be highly susceptible forming highest zone of inhibition, suggesting thatT. bellerica was strongly inhibitory towards this organism. These pathogens were highly sensitive to the methanol extract forming 14.0 to 30.0 mm zone of inhibition suggesting that the methanol extract ofT. bellerica was more effective than crude extract against most of the microbes tested exceptE. coli (enteropathogen) andP. aeruginosa. The minimal inhibitory concentrations (MICs) of crude and methanol extracts were determined by broth dilution technique which ranged from 300 to >2400 μg/ml and 250 μg to >2000 μg/ml respectively, indicating thatT. bellerica was highly effective againstS. aureus with lower MIC values. There were some biochemical alterations induced byT. bellerica. These results indicate thatT. bellerica dry fruit possesses potential broad spectrum antimicrobial activity.