A comparative study of antibacterial potentials of leaf extracts of some selected trees from Benue State University Campus on Staphylococcus aureus AND Escherichia coli

Introduction: Medicinal Plant with antimicrobial properties are of great significance in therapeutic treatments of disease caused by bacteria. Their antibacterial properties are due to compounds synthesized in their cell sap during secondary metabolism, their antibacterial activity has shown that plants represent a potential source of novel antibiotic prototypes. This study aims to investigate the antibacterial potential of three plant extracts on S. aureus and E. coli. Method: A comparative study of the antibacterial potentials of water and ethanolic leaf extracts of three plants, Parkia biglobosa, Khaya senegalensis and Daniellia oliveri, was carried out. Extracts at various regimes of concentrations, 0.2 g/ml, 0.4 g/ml, 0.6 g/ml, 0.8 g/ml and 1.0 g/ml were tested against Staphylococcus aureus and Escherichia coli. The disc diffusion method of Kirby Bauer with slight modification was adapted in determining zones of inhibition. Statistical significance was considered at (p<0.05). Results: Ethanolic leaf extract of P. biglobosa recorded the highest zone of inhibition (20.0 mm) at 1.0 g/ml on S. aureus, while ethanolic leaf extract of D. oliveri had the least zone of inhibition (6.33 mm) at 0.2 g/ml on E. coli. K. senegalensis was most effective on E. coli with grand mean inhibitory effect of (13.33 mm and 12.13 mm) on ethanol and water extract respectively, while P. biglobosa was most effective on S. aureus with grand mean inhibitory effect of (13.00 mm and 12.47 mm) on ethanol and water extracts respectively. No significant difference in the grand mean inhibitory effect of the three plants on test bacterial or the type of solvent used. Conclusion: The three plants are potential useful antibacterial agents, inhibiting bacterial growth at all concentrations of the study.