Antibacterial evaluation of diarrheal herbs used by K'Ho people in Bidoup-Nui Ba national park
Keywords:Agar diffusion, antibacterial, diarrhea, extract, medicinal plant, Bidoup-Nui Ba
This study is to evaluate antibacterial activity of five medicinal plant, collected from Bidoup-Nui Ba National Park, Lam Dong province, Vietnam, which are used by K’ho minority population to treat diarrhea. We used agar diffusion method to test the activity of ethanol 70% extracts of five plants against 13 pathogenic bacterial strains and 5 beneficial bacterial strains. We found that Medinilla septentrionalis, Polygala paniculata, Chromolaena odorata and Streptocaulon juventas showing potent activity against all of 13 pathogenic bacterial strains. Among these, M. septentrionalis showed strong antibacterial activity at concentration from 50 mg/ml compared to the others. In contrast, Dacrycarpus imbricatus showed no activity with Enterotoxigenic Escherichia coli at concentration 400 mg/ml. The extracts also inhibited some beneficial bacteria at concentration from 200 to 400 mg/ml. Surprisingly, Dacrycarpus imbricatus and Polygala paniculata did not influence any beneficial bacteria at concentration 400 mg/ml. In summary, all of five plant extracts had potent activity against various diarrheal bacteria and impact slightly on some beneficial bacteria. The antibacterial activity increased in accordance with the concentration. This study provided new scientific evidences to support the potential of five medicinal plants in diarrheal treatment, being basis knowledge to study deeply about their bioactivities.