The present study focused on the antimicrobial compounds production from Streptomyces clavuligerus isolated from Egyptian soil. The results revealed that the isolate had a broad spectrum antimicrobial activity against Escherichia coli NCTC 10416, Salmonella typhi NCIMB 9331, Bacillus subtilis NRRL B-543, Staphylococcus aureus ATCC 29213 and Candida albicans ATCC 10231. The isolate was identified according to the morphological and molecular techniques identification as Streptomyces clavuligerus. Different experiments were conducted to study the optimum conditions for the highest antimicrobial productivity of Streptomyces clavuligerus. Results indicated that, the optimum medium for the production of antimicrobial compound(s) was YPSS- medium included carbon source starch at concentration of 10 g/l and nitrogen source urea at concentration of 6 g/l. In addition the optimum incubation period was 7 days at incubation temperature 30oC if the optimum agitation speed was 150 rpm and initial pH was 6.5 using phosphate buffer. On the other hand, peel potato was the best carbon by product source while whey was the best nitrogen by product source. The extraction, purification and structure identification of the antimicrobial agent(s) produced by Streptomyces clavuligerus, were carried out by UVanalysis, IR and Mass spectrum which identified as Clavulanic acid and Holomycin.
Key words: Streptomyces clavuligerus, Optimization conditions, Clavulanic acid and Holomycin.
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