Antibacterial Evaluation and Phytochemical Analysis of Selected Medicinal Plants against Some Pathogenic Enteric Bacteria in Gozamin District, Ethiopia

Antibacterial activity evaluation and Phytochemical Analysis of aqueous, chloroform, methanol and ethanol crude extracts of thirteen medicinal plants species that were selected based on ethno botanical information on their traditional use were tested for treatment of enteric disease in Gozamin District. The study has been carried out from January 5, 2014 to February 15, 2015. All of these plants were extracted following standard methods (Soaking extraction method and agar-well diffusion) to screen of potential anti-microbial substance. All crude extracts of those medicinal plants were tested against standard reference strains including Escherichia coli, Staphylococcus aureus, Shigella sonnei, Pseudomonas aeruginosa and Salmonella typhimurium. The highest antibacterial activity (17 mm) was observed from chloroform leaf extract of Eucalyptus globules against E. coli and leaf extract of Verbena officinalis (13.6 mm) extract against Shigella sonnei, followed by methanol leaf extract of Cordia africana (12.8 mm) against E. coli. More over Eucalyptus globules was positive for all bioactive compounds tested except saponins and Verbena officinalis was positive for all bioactive ingredients tested except alkaloids. In general extracts of Eucalyptus globules leaves exhibited the highest potency against E. coli and extract Verbena officinalis showed highest potency against Shigella sonnei. Thus, this study confirmed the alternative sources of medicine for pathogenic enteric bacteria tested.