ABSTRACT

The interest in plant remedies has been spurred by several factors including their effectiveness, the high cost and side effects of orthodox medicines.

This study was aimed to determine the antimicrobial activity of two medicinal plants (Chromolaena odorata and Azadirachta indica) against some bacterial pathogens (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Salmonella typhi), and also to determine the phytochemical content of the two medicinal plants. 

The anti-bacterial activity testing of the methanol extracts of the leaves of these plants were done using the agar disc diffusion method to measure the diameter zone of inhibition and broth dilution assay to assess the Minimum Inhibitory Concentration (MIC) of the plant extracts against susceptible organisms. The methanol extract of Chromolaena odorata had inhibitory effect against Staphylococcus aureus, Escherichia coli, Salmonella typhi and methanol extract of Azadirachta indica against Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi. The plant extract of Chromolaena odorata had no inhibitory activity on Pseudomonas aeruginosa while Azadirachta indica had no effect on Escherichia coli. The result of this study confirms the use of theses medicinal plants in treating microbial infection and can serve as source of synthetic drugs.