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

Bacteriological analysis of spent engine oil contaminated soil planted with cowpea (Vigna unguiculata)

The bacteriological analysis of soil contaminated with spent engine oil (SEO) planted with cowpea was investigated. The aim of this study was to detect the microbial degradation of SEO in soil and how it affects the microbial activity and the effects of SEO on the growth of cowpea. SEO collected from a mechanic workshop in Ilorin was introduced into soil in varying concentrations. The experimental set up was in triplicates with six treatments of SEO. Soil samples were taken every week for the duration of six weeks for laboratory analysis. Plant growth parameters were measured every week after planting. The pH of the soil and the bacterial population of the soil were also observed. Findings revealed that the plant growth parameters were significantly reduced as the concentration of SEO increased in the soil. Bacterial counts were also determined and a total of six bacterial species were isolated from the soil samples. Bacillus subtilis, Micrococcus luteus, Pseudomonas aeruginosa and Pseudomonas putida occurred in the control and contaminated soil samples. Bacterial counts ranged from 1.89×105 to 4.25×105 cfu/ml in the soil samples with the highest occurring in the control and the least occurring in 224ml of SEO. SEO contaminated soil has adverse effect on cowpea and on bacterial flora of the soil. The results of this study revealed that Pseudomonas aeruginosa, Micrococcus luteus and Bacillus subtilis can utilize SEO in the soil. They could be harnessed for use in bioremediation of soil polluted with petroleum and petroleum products.Key Words: Bacteria, Spent engine oil, Soil, Cowpe