Xylitol의 생산성 향상을 위한 Two-stage Fed-batch 배양조건의 최적화

A two-stage fed-batch fermentation was carried out to increase xylitol productivity by Candida tropicalis. The first stage for cell growth was performed in the pH-stat and continuous fed-batch modes. The higher cell growth and lower ethanol production obtained in the fed-batch mode where the growth medium was fed when pH of culture broth increased over 5.7. And also the effect of oxygen transfer on xylitol production was investigated by changing agitation speed under 0.5 vvm of aeration. The maximum xylitol productivity and yield were obtained at 500 rpm of agitation.

Xylitol의 생산성을 높이기 위해 two-stage fed-batch를 수행하였다. Glucose가 고갈되어 pH가 5.7에서 올라가면 glucose를 공급하는 방법에서 최종세포의 OD 185.0과 최종 ethanol 농도 1.0 g/L를 얻었다. 산소전달에 대한 xylitol의 생성 영향에서는 통기량 1 vvm에서 500 rpm의 교반속도일 때 xylitol 수율 55.2%와 생산성 $2.19\;g-xylitol/L\;{\cdot}\;h$를 얻었다.