ANTIMICROBIAL EFFICACY OF MORINGA OLEIFERA ON SELECTED BACTERIAL ISOLATES FROM HOSPITALS WITHIN BAUCHI METROPOLIS

ABSTRACT Wound and urinary tract infections caused by multidrug-resistant bacteria remain a serious public health concern in developing countries, particularly in Nigeria. In recent years, Moringa oleifera has attracted increasing scientific interest for its antimicrobial potential as an accessible and affordable natural remedy. This study investigated the antimicrobial activity of Moringa oleifera leaf extract against two hospital-associated bacterial pathogens—Escherichia coli and Klebsiella species—isolated from clinical samples obtained in Bauchi Metropolis. Fresh Moringa oleifera leaves were collected from trees within Bauchi and air-dried under shade before extraction using ethanol and distilled water as solvents. The antimicrobial susceptibility of the extracts was determined using the agar well diffusion method, while the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were obtained through standard broth dilution assays. Ciprofloxacin (5 μg) served as the positive control, and distilled water as the negative control. Results showed that both ethanol and aqueous extracts of Moringa oleifera exhibited inhibitory effects on the test organisms, with activity increasing in a concentration-dependent manner. At 50 mg/mL, E. coli and Klebsiella showed mean inhibition zones of 10.5 mm and 12.1 mm respectively, which increased to 18.2 mm and 20.3 mm at 200 mg/mL. Comparatively, ciprofloxacin produced inhibition zones of 15.8 mm (E. coli) and 17.2 mm (Klebsiella). The MIC values were 5 mg/mL for E. coli and 4 mg/mL for Klebsiella, while both organisms recorded MBC values of 6 mg/mL. Statistical analysis (ANOVA) revealed significant differences (p < 0.05) between concentrations, confirming a dose-dependent antimicrobial response. In conclusion, the findings demonstrate that Moringa oleifera leaf extracts possess significant antibacterial properties against E. coli and Klebsiella species. Although not as potent as ciprofloxacin, the extract’s broad-spectrum activity and low MIC values indicate its potential as a supplementary or alternative therapeutic agent, particularly in resource-limited settings where antibiotic resistance is a growing concern. Further purification and phytochemical analysis are recommended to identify the specific bioactive compounds responsible for the observed effects.