Assessment of Moringa oleifera (Lam) Leaf Extracts for Their Antibacterial Efficacy Against Staphylococcus aureus Bacteria

Abstract

This study aimed to evaluate the antibacterial activity of Moringa oleifera (Lam.) leaf extract from the Moringaceae family against selected bacteria using the agar well diffusion method. Nutrient Agar (NA) media was prepared following the manufacturer’s instructions. Sterile agar plates were inoculated with the test culture by surface spreading using sterile wire loops, ensuring uniform distribution. Concentrations of 30, 60, 90, and 120 mg/ml, derived from dry leaf powder, were utilized for antibacterial analysis via agar well incorporation. Plates were prepared and allowed to solidify on Petri dishes, then seeded with the test bacterium. Four holes were made in each plate using a sterile 2.0 mm diameter cork borer. Each hole was filled with a specific extract concentration and plain sterile agar. The plates were incubated at 37°C for 24 hours, and the diameters of inhibition zones were measured using a meter rule. The aqueous, ethanol, and methanol extracts of Moringa leaves exhibited inhibitory effects on the growth of tested bacteria. Specifically, the inhibitory effect on Escherichia coli was significantly higher (P<0.05) than Staphylococcus aureus for aqueous, ethanol, and methanol extracts. Moreover, ethanol and methanol extracts demonstrated significantly higher (P<0.05) inhibitory effects at 120 mg/ml concentrations. The powder derived from Moringa leaves showed promising antibacterial activity against the tested gram-positive bacterium, Staphylococcus aureus.