Phytochemical Analysis and Antibacterial Effect of Medicago sativa and Moringa oleifera on Selected Bacteria Isolates

Abstract

In vitro antibacterial activities of the crude leaf extract of Moringa oleifera and Medicago sativa were investigated against some bacterial isolates (Escherichia coli, Staphylococcus aureus, Bacillus cereus and Pseudomonas aeroginosa) using the agar well diffusion and broth dilution techniques. The ethanolic crude extract of both plants exhibited significant inhibitory action against all the isolates tested at an initial concentration of 200 mg/ml except for Bacillus cereus. The minimum inhibitory concentrations exerted by the ehthanolic extract of Moringa oleifera against the bacterial isolate ranged from 6.25 mg/ml and 50 mg/ml with Escherichia coli recording the least while Medicago sativa varied from 12.5 mg/ml and 100 mg/ml. the plant leaf extract compared favourably with the control antibiotics used in the study. The phytochemical compounds observed in the leaf extracts are flavonoids, tannin, terpenoids, saponins and alkaloids. Tannin was the phytochemical that had the least concentration in the leaves of the plants. The quantitative yield of the bioactive compounds of the leaf extracts showed that Medicago sativa has highest yield of flavonoid at 3.81% yield and 4.51% for Moringa oleifera. The significant antibacterial activities exhibited by the ethanolic extract of the plants confirmed the therapeutic potentials of these plants in the treatment of various infections in herbal medicine.