Comparative in Vitro Study of the Antibacterial Effect of Moringa oleifera Lam. Seed and Leaf on Bacteria Associated with Urinary Tract Infections

Urinary tract infections (UTIs) remain a major global health concern, increasingly complicated by antimicrobial resistance. Moringa oleifera Lam. is a widely used medicinal plant with documented antimicrobial, anti-inflammatory, and antioxidant properties, yet comparative evaluations of its leaf and seed antibacterial activities remain limited. This study investigated and compared the in vitro antibacterial effects of ethanolic and aqueous extracts of M. oleifera leaves and seeds against common uropathogenic bacteria. Extracts were prepared by maceration in ethanol and distilled water. Antibacterial activity was assessed using agar well diffusion and broth microdilution techniques against Escherichia coli, Klebsiella spp., Proteus spp., Pseudomonas spp., and Staphylococcus aureus. Minimum inhibitory (MIC) and bactericidal (MBC) concentrations were determined. Data were analyzed using one-way ANOVA and Pearson correlation. Ethanolic extracts exhibited significantly higher antibacterial activity than aqueous extracts (p < 0.05). The ethanolic leaf extract produced the largest inhibition zones (18-23 mm) and lowest MIC values (15.63-31.25 mg/mL), particularly against Klebsiella and Proteus spp. The ethanolic seed extract showed notable activity against S. aureus (MIC: 31.25 mg/mL). A strong negative correlation (r = –0.86, p < 0.01) was observed between inhibition zones and MICs, confirming consistency between diffusion and dilution assays. Ethanolic extracts of M. oleifera leaves and seeds demonstrate broad-spectrum antibacterial efficacy, supporting their potential as natural alternatives or adjuncts in managing UTIs. Further isolation, purification, and clinical validation of the active constituents are warranted to develop standardized phytotherapeutic agents.