DOI: 10.36347/sajb.2015.v03i03.015

Pages: 320-324

Extracts of the leaves, bark and root of Psidium guajava as well as the leaves of Moringa oleifera were investigated for antibacterial activity against Staphylococcus aureus, Streptococcus spp, Klebsiella spp, Proteus spp and Psuedomonas spp. The disc diffusion method was adopted using extract concentrations of 10-280 mg/ml. The qualitative phytochemical compositions of both plants were studied. Phytochemical test on the extracts revealed the presence of saponins, alkaliods, tannins, flavoniods, steroids, phenol and glycosides. Minimum Inhibition concentration (MIC) was obtained by plotting logarithm of the concentrations of the extract against the squares of the zone of inhibition. The antilogarithm of the intercept gave the MIC values. Leaves extract of Moringa oleifera at 280 mg/ml showed good inhibitory effect against Streptococcus spp, comparable to synthetic antibiotics such as Ciproflox and Reflacine. Similarly, the inhibitory effect of P. guajava bark at 280 mg/ml against Klebsiella spp competed favourably with Reflacine. Extracts of P. guajava leaves, root and the synthetic drug Reflacine gave equal antimicrobial effect against Pseudomonas spp. These results indicate that extracts of P. guajava and M. oleifera can be used for the treatment of pathogenic infections caused by some bacteria.