Phytochemical Screening and Antibacterial Activity of Moringa oleifera Leaf Extracts from Sokoto State, North West Nigeria

Moringa oleifera, widely cultivated across arid and semi-arid zones of Nigeria, is increasingly recognised for its medicinal and nutritional properties, yet comprehensive chemical profiling from specific Nigerian localities remains limited. This study performs phytochemical screening and evaluates the antibacterial activity of aqueous and ethanolic extracts of Moringa oleifera leaves sourced from three local government areas in Sokoto State, North West Nigeria. Qualitative phytochemical tests are carried out to detect the presence of alkaloids, flavonoids, tannins, saponins, phenols, glycosides, and steroids using standard colorimetric and precipitation reactions. Antibacterial activity is assessed using the agar well diffusion method against selected clinical isolates: Staphylococcus aureus, Escherichia coli, and Klebsiella pneumoniae, obtained from the Usmanu Danfodiyo University Teaching Hospital laboratory. Minimum inhibitory concentrations are determined for extracts showing appreciable zones of inhibition. The study also compares the phytochemical richness of samples collected during dry and wet seasons to establish seasonal influence on secondary metabolite accumulation. Results are anticipated to validate traditional claims of antibacterial efficacy and support the development of plant-based pharmaceutical alternatives in resource-limited settings. This work contributes to ethnopharmacological documentation of northern Nigerian medicinal plants and provides evidence useful for product formulation in rural health initiatives. Keywords: Moringa oleifera, phytochemical screening, antibacterial activity, Sokoto, ethnopharmacology