Z.P. Bhathena, D. Koppar, H. Tupali, V. Mhatre, R. Chitgupi, K. Shah
Abstract
Screening of terrestrial ecosystems using various soil sampies yieicied 56 antinomycetes and 17 bacterial isolates, whose activity against E. coil and S. aureus shortlisted S actinomycetes and 2 bacterial isolates as potent antagonistic activity producers. Though they showed narrow spectrum, one actinomycete isolate, coded AA 19, was found to show a broad antimicrobial spectrum, active against S. typhi, S. paratyphi A, S. paratyphi B. Shigella flexneri, C. tropicalis, and Aeromonas species. Hence. AA19, a potent antibiotic producer with activity against the representative test cultures of S. aureus, E. co/i and C. tropicalis was selected for further studies. Optimization of its production conditions in terms of temperature, aeration, pH, carbon and nitrogen sources for amplifying the antibiotic production by the actinomycetes isolate AA-19 was carried out. Maltose and soya bean were the preferred carbon and nitrogen sources in the ratio 0.5:0.5, whereas room temperature, shaker conditions and neutral pH were found to be more conducive for antibiotic production.