Antimicrobial Effect of the Leaf Extracts of Moringa oleifera on Some Selected Clinical Bacterial Isolates

Antibiotic susceptibility pattern of two batches of clinical isolates consisting of eight organisms were collected from the Department of Medical Microbiology, University of Ilorin Teaching Hospital (UITH). The isolates collected for the first batch were from wound infections and include Staphylococcus aureus, Non-haemolytic Streptococcus, Escherichia coli, Proteus sp, Pseudomonas sp, Klebsiella pneumonia, Vibrio cholera and Salmonella typhi. The organisms in the second batch include Staphylococcus aureus, Streptococcus thermophilus, Escherichia coli, Pseudomonas sp, Klebsiella pneumonia, Bacillus anthracis, Salmonella typhi and Vibrio cholera. The test showed that all the test organisms were susceptible to Ofloxacin, Ciprofloxacin, Pefloxacin and Gentamycin with reasonable zones of inhibition. Cold Methanoic Extract, 95% Ethanoic Extract, Absolute Ethanoic Extract and Distilled Water Extract of Moringa oleifera were assayed for in vitro antibacterial activity using agar diffusion method. The first set of organisms produced zones of inhibition ranging from 1mm-6.5mm. The second set of organisms produced zones of inhibition ranging from 2mm-21mm. The result showed that the potency of the extracts depend on the solvent used for the extraction and method of extraction. Cold Methanoic Extraction (CME) was found to be most effective. The extract has its highest activity at pH 4.29. The extracts were found to be bacteriostratic but not bacteriocidal.Keywords: Moringa oleifera, antimicrobial effect, leaf extractsand clinical isolate