ANTAGONISTIC PROPERTIES AND CHARACTERIZATION OF ISOLATES FROM INDIGENOUS BLACK SOAP

Antagonistic properties of microbes have been traced to the presence of some antimicrobial agents produced by some of these organisms. The objectives of this paper were to investigate the antagonistic properties of isolates from indigenous black soap and to characterize the inhibitory substance(s) of the isolates. The indigenous black soap was prepared using Saponification method and the microbial load was determined. The antagonistic properties of indigenous microfloral from indigenous black soap were investigated using the conventional streak, novel ring and well diffusion methods. The test was conducted on six organisms viz Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, Candida albicans, Trichophyton rubrum, and Klebsiella pneumoniae. Antagonism was measured by zone of inhibition between the bacterial streak/ring. The bacterial load of the soap ranged from 3.4x104-1.9x104 CFU/g while the fungal spore was 2.7x104-1.1x104 SFU/g. The bacteria isolated were: Bacillus cereus and Bacillus subtilis and S. aureus while the fungi isolated were: Aspergillus niger, Botrytis cinerea, Fusarium oxysporium. Bacillus cereus and Bacillus subtilis inhibited the growth of all the test organisms except E. coli and T. rubrum while C. albicans and K. pneumoniae were susceptible to S. aureus (11 mm and 08 mm respectively). The inhibitory properties of these organisms may be due to the presence of catalase enzyme or other metabolites.