Antibacterial Activity of Ethnic Vegetables Consumed by the Indigenous People Living in Chittagong Hill Tracts

Abstract

Aim: Emergence of multidrug resistant bacteria has made the treatment of infectious diseases much difficult. Plant or herbal antibiotics have been reported to be effective against multiple drug resistant bacteria. In line of exploring newer antibacterial agent(s), this study describes the screening of ten selected ethnic vegetables for their antibacterial activities against fourteen bacterial strains. Methodology: Fresh plant sample was extracted using aqueous and ethanol solvent by cold-extraction. Disc diffusion method was employed to screen the antibacterial activity of fresh and ethanol extracts of ethnic vegetables consumed by the ethnic people of Chittagong Hill Tracts. Results: Among the tested plant extracts, fresh extracts of Kamino (Caesalpinia digyna Rottler) leaves, Chikipung (Rumex vesicarius L) and Ammpata (Mangifera indica L); and ethanol extracts of Kamino leaves showed potent antibacterial activity against most of the pathogens. Gram positive bacteria were found to be more sensitive than the gram negative strains. Fresh extract of Kamino leaves showed a strong antibacterial activity against of the bacteria tested (20 mm to 32 mm zone of inhibition). Highest antibacterial activity was observed against Sercina lutea (32 mm zone of inhibition). Against Escherichia coli and Shigella dysenteriae type-1, Kamino leaves indicated 24 and 21 mm zone of inhibition respectively. Ethanol extract of Kamino leaves showed mild activity (10 mm to 15 mm zone of inhibition) against the tested strains. Conclusion: Samples of ethnic vegetables investigated in this study are found to possess antibacterial activity. Fresh extract of some samples, in comparison with their ethanol extract has shown higher antibacterial activity. These findings indicate the possibility of further research on these  plant to find effective antimicrobial compounds from these plants.