Phytochemical Screening and Antimicrobial Activity of Moringa oleifera Leaf Extracts in Sokoto State

The increasing prevalence of antibiotic-resistant bacteria has renewed global interest in plant-based antimicrobial compounds. This study evaluates the phytochemical composition and antimicrobial properties of crude extracts obtained from Moringa oleifera leaves sourced from rural farming communities in Sokoto State, North West Nigeria. Leaves were shade-dried, pulverised, and subjected to sequential solvent extraction using hexane, ethyl acetate, and methanol. Phytochemical screening was performed to detect the presence of alkaloids, tannins, saponins, flavonoids, and phenolic compounds using established colorimetric and precipitation methods. Antimicrobial activity was evaluated against selected clinical isolates, including Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans, using the agar well diffusion method. Minimum inhibitory concentrations were determined by the broth microdilution technique. Results revealed that the methanol extract demonstrated the broadest spectrum of antimicrobial activity, with significant inhibition zones observed against both gram-positive and gram-negative organisms. Flavonoids and tannins were identified as the dominant phytochemical classes potentially responsible for the observed bioactivity. The findings support the traditional use of Moringa oleifera in managing infectious conditions and provide a scientific basis for further pharmaceutical investigation. This study adds to the growing body of evidence on the medicinal value of locally available plants in the North West geopolitical zone. Keywords: Moringa oleifera, phytochemical screening, antimicrobial activity, Sokoto, plant extracts