Phytochemical Analysis and Antibacterial Activity of Moringa oleifera Leaves Extracts against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa

Abstract

This study tests the antibacterial activities of Moringa oleifera leaf extract against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa, obtained from Microbiology laboratory, Al-Hikmah University Ilorin. Phytochemical analysis reveals the presence of tannins in all the three extracts (Aqueous, ethanolic and N-hexane), while. flavonoids, alkaloids and Saponins were only present in the Aqueous and ethanolic extracts. The leaves extracts were screened for antibacterial activity by agar well diffusion method, employing five different extracts concentrations (100mg/ml, 80mg/ml, 60mg/ml, 40mg/ml and 20mg/ml). The aqueous extracts had a mean activity of 11.50±0.70mm, 7.50±0.70mm and 8.5±0.70mm for S. aureus, E. coli and P. aeruginosa respectively. The ethanol extracts had a mean activity of 12.00±1.41mm, 10.00±1.41mm and 8.00±1.21mm for S. aureus, E. coli and P. aeruginosa respectively, while the N-hexane extracts exert no any activity. The antibiotics discs exert more inhibitory effect compared to the extract. The MIC for the aqueous extracts are at a concentrations of 60mg/ml for S. aureus, 80mg/ml for P. aeruginosa and 80mg/ml for E. coli. While that of the ethanol extract of the leaves are at a concentration of 60mg/ml for S. aureus, 80mg/ml for E. coli and 100mg/ml for P. aeruginosa. The MBC for the aqueous Extract of the leaves are at a concentration of 80mg/ml for S. aureus, 100mg/ml for P. aeruginosa and 100mg/ml for E. coli, while that of the ethanol extract are at a concentration of 80mg/ml for S. aureus and 100mg/ml for E. coli), while no any MBC was recorded for P. aeruginosa. The antibacterial activity tests indicate that the ethanol extract was more active. Among the three isolates, S. aureus is more sensitive to the aqueous and ethanol extracts. The activity exhibited by the extracts may be related to the presence of a number of Phytoconstituents.