Production of Avermectin from Streptomyces avermitilis NRRL8165 by optimization of medium composition

In this study, we tried to optimize the composition of medium and culture conditions for the total avermectin and avermectin B1 production from S. avermitilis, which is a natural producer of avermectin family. Among various carbon and organic nitrogen sources tested, fructose and malt extract were most effective on avermectin production. Next addition of polyethylene glycol and $K_{2}HPO_{4}$ in medium significantly improved the intracellular contents of avermectin. Thus the optimized medium composition was 50 g/L fructose, 30 g/L malt extract, 5 g/L casamino acid, 2.5 g/L PEG 3,350, and 1 g/L $K_{2}HPO_{4}$, which increased the avermection production from10 to 478 mg/L. The contents of avermectin B1 complex was about 50% of the total amount of avermectin.

본 연구에서 수행한 avermectin 생산을 위한 배지 최적화에서 기존의 총 avermectin의 함량 10 mg/L를 470 mg/L까지 증가시켰으며, 이 중 광범위 활성을 가지는 avermectin B1도 50%에 달했다. 최적화된 배지 조성은 50 g/L fructose, 30 g/L malt extract, 5 g/L casamino acid, 2.5 g/L PEG 3,350, and 1 g/L $K_{2}HPO_{4}$이다. $K_{2}HPO_{4}$와 fructose, malt extract가 avermectin 생합성에 크게 작용하는 것으로 추정된다.