Chemical Composition and In-vitro Antibacterial Activity of the Essential Oil of Nigerian Moringa oleifera Lam. Flowers

Abstract

Aims: To investigate the chemical composition and antibacterial activity of essential oil isolated from flowers of Moringa oleifera (MO) grown in Western Nigeria. Methodology: Gas chromatography–mass spectrometry (GC-MS) analysis was carried out for identification and determination of the phytochemical constituents of the oil. Standard microbiological methods was also employed to evaluate the antibacterial activities of the oil. Results: GC-MS analysis revealed a total of twenty-five phytochemical constituents, with the major constituents found to be nonanal (17.3%), trans-geranyl geraniol (13.5%) and eicosane (12.3%), α-terpineol (7.2%), methyl palmitate (4.6%) and methyl octadec-9-enoate (4.1%). The antibacterial assay, using standard microbiological methods, showed that the oil had inhibitory effects against both Gram-positive (Bacillus cereus, Micrococcus luteus and Staphylococcus aureus) and Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria isolates. The minimum inhibitory concentrations (MICs) exhibited by the essential oil against test bacteria ranged between 1.25 mg/mL and > 5 mg/mL. Conclusion: Essential oil of Nigerian Moringa oleifera flowers contains biologically active ingredients and possess some level of antibacterial activity.  The oil can be a good source of antibacterial agents.