Development of balanced medium composition for improved rifamycin B production by isolated Amycolatopsis sp. RSP-3.

Aim:  To develop optimum fermentation environment for enhanced rifamycin B production by isolated Amycolatopsis sp. RSP-3. Methods and Results:  The impact of different fermentation parameters on rifamycin B production by isolated Amycolatopsis sp. RSP-3 was investigated using Taguchi methodology. Controlling fermentation factors were selected based on one variable at a time methodology. The isolated strain revealed more than 25% higher production compared to literature reports. Five different nutritional components (soyabean meal, glucose, potassium nitrate, calcium carbonate and barbital) and inoculum concentration showed impact on rifamycin B production at individual and interactive level. At optimized environment, 65% contribution was observed from selected fermentation parameters. Conclusions:  Soyabean meal and calcium carbonate were the most significant factors among the selected factors followed by barbital and potassium nitrate. Glucose, however, showed the least significance on rifamycin B production with this strain. A maximum of 5·12 g l−1 rifamycin B production was achieved with optimized medium containing (g l−1) soyabean meal, 27; glucose, 100; potassium nitrate, 4; calcium carbonate, 3 and barbital, 1·2. Significance and Impact of the Study:  The present study signifies identification of balanced medium component concentrations for improved rifamycin B production by isolated Amycolatopsis sp. RSP-3. This strain requires organic and inorganic nitrogen sources for effective product yield. Yet at individual level, organic nitrogen source has c. nine-fold higher influence compared to inorganic one.