본 연구에서 탄소원이 고갈된 후 용존산소농도로 epothilone의 합성을 조절할 수 있음을 증명하였다. 선행연구로써, soluble starch를 탄소원으로 결정하였고, lactose와 yeast extract의 최적농도가 각각 4 g/L, 0 g/L임을 알 수 있었다. 탄소원이 고갈된 환경에서 산소농도가 낮을 경우 균체가 epothilone을 다량으로 합성하였다. 산소 공급을 조절할 수 없는 flask의 경우 배양이 진행되면서 균제농도가 증가하고 자연적으로 산소 농도도 감소하므로 epothilone이 합성되지만, 생물반응기의 경우 탄소원의 고갈 후 산소 농도를 최대한 낮게 유지시키는 것이 epothilone의 생산을 증가시켰다.
The biological production of a potent anticancer agent, epothilone, by Sorangium cellulosum was carried out using flask and fermentor cultures. Soluble starch was selected as the main carbon source and the concentrations of lactose and yeast extract were optimized at 4 and 0 g/L, respectively, when using the flask cultures. In the fermentor cultures, the cells were cultivated at a high DO level of more than 80% of air saturation in the growth stage and then the DO level was controlled at about 50, 20 or 1-2% when the carbon source was exhausted. The epothilone production increased with decreasing DO level after the exhaustion of the carbon source, and the maximum concentration of epothilone was 5.4 mg/L. It was found that the DO level had significant regulation effects on the epothilone production.
