In-vitro Antimicrobial Activities and Phytochemical Screening of Selected Plant Extracts against Some Medically and Agriculturally Important Pathogens

Abstract

In Ethiopia, many plants are used for medicinal drive-by old-style naturopaths without any scientific justification for their therapeutic values. The principal aim of this study were to evaluate the in vitro antibacterial and antifungal activities of the leaf, root and stem bark extracts of Rhamnus prinioides (gesho), Justicia schimperiana (sensel) and Ruta chalepensis (Tena adam) against some common pathogenic species of bacteria and fungi. The results of this study shown that the crude extracts of ethanol, methanol, hexane and water crude extracts had antimicrobial activities on most bacterial and fungi species of some solvent extracts. Ethanol and methanol crude extracts had the highest growth inhibitory effects as compared with those of the aqueous and hexane crude extracts. But, the four solvent crude extracts had fewer antimicrobial activities than commercially available drug(chloramphenicol and clotrimazole). Campylobacter jejuni and Staphylococcus aureus were found to be the most vulnerable microbes to the crude ethanol (99.5%). The growth-inhibitory events of the crude extracts were found to be significantly dissimilar for both concentrations (30 and 60 mg/ml) in all plant parts (p < 0.05). In general, this study did not only indicate that the antibacterial activities of R. prinioides (gesho), J. schimperiana (sensel) and R. chalepensis (Tena adam). It also accesses a scientific justification for its old-style use against some diseases.