Optimization of culture conditions of Streptomyces rochei (MTCC 10109) for the production of antimicrobial metabolites

Fermentation and culture conditions were studied in shaken-flask culture to induce the production of greater amounts of antimicrobial metabolites by Streptomyces rochei (10109). Antimicrobial metabolite production started after 48 h incubation and reached its optimum level at 20% inoculum size at 120 h, at which point the metabolites showed maximum antifungal and antibacterial activity against selected human pathogenic microorganisms (Candida albicans, Staphylococcus aureus and Escherichia coli). Optimal production occurred at pH 7.5 and temperature 32°C, with 2% glycerol and 1% peptone as the carbon and nitrogen sources respectively. The effects of adding sea water (optimum 30%) and NaCl (optimum 1%) were also evaluated.