ABSTRACT

The antimicrobial activities of traditional black soaps prepared locally (Ncha-Nkota) and one prepared commercially (Dudu Osun) widely used by different tribes in Nigeria such as Hausa, Yoruba, Nupe and Igbo against skin infections were examined against some pathogenic microorganisms (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Candida albicans) using agar-well diffusion method. The pattern of inhibition varied with the soap concentration and the organisms tested. The two soaps were more effective on Candida albicans with the locally prepared soap (Ncha-Nkota) having a maximum zone of growth inhibition of 11.7mm at 100mg/ml while the commercially prepared soap (Dudu Osun) had a maximum zone of growth inhibition of 12mm at 100mg/ml, followed by Staphylococcus aureus and Pseudomonas aeruginosa. Escherichia coli had the least zone of growth inhibition of 8mm and 8.7mm at 100mg/ml for Ncha-Nkota and Dudu Osun respectively. The minimum inhibitory concentration (MIC) was found to be 25mg/ml for Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans, while Escherichia coli had minimum inhibitory concentration of 50mg/ml for the two soaps worked with. The antimicrobial activities exhibited by these two soaps in this study could be attributed to the presence of its constituents which signifies the potential of the soap as a topical therapeutic agent. These findings therefore, justify the traditional medicinal use of these two soaps.