Susceptibility of optimization of medium components for the production of antimicrobial secondary metabolites by streptomyces globosus isolated from KAU

Abstract

The genus Streptomyces represents a group of microorganisms that are widely distributed in nature as the greatest source of the commercially available antibiotics. Objective: In this study, a wide group of actinomycetes strains were isolated from KAU. Further, analysis and evaluate their antibacterial potential against a panel of bacterial pathogens. Methods: In the present study, 12 soil samples were collected from different localities of Al-Baha, Saudi Arabia. Actinomycetes were isolated from these samples using serial dilution and plating method on actinomycetes isolation agar. The antimicrobial activity of actinomycetes was tested against different bacteria. The effect of different media, carbon, nitrogen, and phosphorus sources, on the growth and antibacterial effect against E. coli ATCC35218, E. coli ATCC25922, Salmonella sp., P. aeruginosa ATCC27853, S. aureus ATCCBAA977, and St. pneumonia ATCC49619 were optimized. The results showed that starch-nitrate agar was the best media for the antibacterial activity for S. globosus. The maximum antimicrobial efficacy was produced when S. globosus utilized the starch as a carbon donner. Furthermore, the highest antibacterial activity of S. globosus was created when inorganic nitrogen sources were added, and the best nitrogen source that supported antibacterial production was ammonium sulfate. Di-potassium hydrogen phosphate was the optimum phosphorus sources with 1.5% sodium chloride. Conclusion: Further studies for purification of bioactive metabolites and