Antimicrobial activity of essential oil and various extracts of fruits of greater cardamom

Greater cardamom (Amomum subulatum Roxb. Zingiberaceae) commonly known as "Bari ilaichi" is a well known plant used in Ayurvedic and Unani medicine. It has been used for the treatment of various diseases and disorders like gastric ulcer. Therefore antimicrobial activity of petroleum ether, methanol and aqueous extracts from leaves and roots, essential oil and isolated vasicine from A. vasica were tested against various microorganisms. Antimicrobial activity was done by disc diffusion method. The zone of inhibition observed was compared with that of standard drugs, ciprofloxacin and fluconazole. Minimum inhibitory concentration was determined against microorganisms used in the study. The results of this study reveal that methanol extract of fruits of A. subulatum shows remarkable antimicrobial activity against Escherichia coli whereas in case of other microorganisms used it was found inferior to the standard drug used. Methanol extract of rind showed good antimicrobial activity against Staphylococcus aureus. It was found that the essential oil isolated was effective against majority of microorganisms used viz. Bacillus pumilus, Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Saccharomyces cerevisiae.