Improved Fermentation Yield of Doramectin from Streptomyces avermitilis N72 by Strain Selection and Glucose Supplementation Strategies

Doramectin is a macrolide antiparasitic that widely used in the treatment of mammalian parasitic diseases. usually produced by Streptomyces avermitilis fermentation using cyclohexanecarboxylic acid (CHC) as precursor; however, growth S. inhibited CHC, resulting low yield doramectin. In this study, high-yielding strain XY-62 was obtained mutant N72 starting strain, then combined with CHC tolerance screening strategy ultraviolet and nitrosoguanidine mutagenesis, 96 microtiter plate solid-state primary sieving shake flask rescreening method. Compared N72, doramectin increased more than 1.3 times, it adaptable to temperature, pH, concentration culture; additionally, viability mycelial enhanced. addition, further studies on revealed accumulation could be glucose supplementation during process, reached 1068 ?g/mL scaling up culture 50 L fermenters; has potential for industrial production. Therefore, mutagenesis an effective way enhance production avermitilis. Our findings can help improve strains