Production of tylosin in solid-state fermentation by Streptomyces fradiae NRRL-2702 and its gamma-irradiated mutant (γ-1).

Aims: To develop solid-state fermentation system (SSF) for hyper production of tylosin from a mutant γ-1 of Streptomyces fradiae NRRL-2702 and its parent strain. Methods and Results: Various agro-industrial wastes were screened to study their effect on tylosin production in SSF. Wheat bran as solid substrate gave the highest production of 2500 μg of tylosin g−1 substrate by mutant γ-1 against parent strain (300 μg tylosin g−1 substrate). The tylosin yield was further improved to 4500 μg g−1 substrate [70% moisture, 10% inoculum (v/w), pH 9·2, 30°C, supplemental lactose and sodium glutamate on day 9]. Wild-type strain displayed less production of tylosin (655 μg of tylosin g−1 substrate) in SSF even after optimization of process parameters. Conclusion: The study has shown that solid-state fermentation system significantly enhanced the tylosin yield by mutant γ-1. Significance and Impact of the Study: This study proved to be very useful and resulted in 6·87 ± 0·30-fold increase in tylosin yield by this mutant when compared to that of wild-type strain. [ABSTRACT FROM AUTHOR]