In-Vitro Evaluation of Stem Bark Extracts of Daniellia oliveri (Hutch and Dalz) for Antimicrobial Activity

A comparative study of the antimicrobial properties of ethanol, methanol, acetone, cold and hot water extracts of Daniellia oliveri was carried out. The extracts were assayed by the minimum inhibitory concentration broth microdilution and minimum bactericidal concentration methods before they were submitted to phytochemical screening. Three Gram positive, three Gram negative bacteria and yeast were used in the assay. All the extracts showed varied activity levels against the test microorganisms. Ethanol, methanol and acetone extract had better antimicrobial activity than the aqueous extracts within the concentration range of 6.25 – 100 mg/ml assayed. The activity was more pronounced against the Gram positive and fungal organisms than the Gram negative bacteria. This study shows that ethanol is the best solvent for extracting pharmacologically active compounds from plant materials. Its extract had the lowest bactericidal concentration of 6.25-25 mg/ml on organisms challenged. Results suggest that the D. oliveri has potential for use as pharmaceutical as well as in ethnomedicinal treatment of infections and diseases.

 C Nwuche, E Eze