Canadian Journal of Pure & Applied Sciences

Abstract: This study was carried out to determine the antibacterial potency of Ocimum gratissimum and Vernonia amygdalina against isolates of Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis and Streptococcus faecalis using sensitivity disc diffusion assay. Extraction was achieved by drying and blending into powdery form, which was separately mixed with distilled water and 70% ethanol in respective flasks. This was properly sieved and stored. The antibacterial properties of extracts of both samples were separately determined against the test isolates. The phytochemical test conducted revealed that the extracts of both samples possessed different biologically active constituents, namely: tannins, flavonoids, saponins, anthocyanins and phlobatannins, while betacyanins were found absent in both extracts. Physicochemical analyses of both extracts showed that a pH range of between 6.0 and 7.5 provided a broad spectrum of activities against a wide range of bacterial infections. Results of antibacterial screenings revealed that the water extracts of both samples were more efficacious than the ethanol extracts. However, both were found to be very active against the test organisms. It was further observed that water extracts were more active against Bacillus subtilis, Staphylococcus aureus and least against Pseudomonas aeruginosa. On the other hand, ethanol extracts were more efficacious against Escherichia coli and Streptococcus faecalis. It has been concluded in this study that O. gratissimum and V. amygdalina can be extensively used tradomedically in the Nigerian folk medicine to treat several bacterial infections, and are thus, recommended as a source of natural product for future use in the management and cure of multi-drug resistant bacterial infections in African continent and the world at large.