Ethanol Production from Sago Starch Using Zymomonas mobilis Coentrapped with Amyloglucosidase

동시고정화된 Amyloglucosidase와 Zymomonas mobilis를 이용한 전분으로부터의 Ethanol 생산

A chitin-immobilized enzyme amyloglucosidase(AMG) and a bacterium Zymomonas mobilis were coentrapped in alginate gel beads. Ethanol production was performed in a packed bed column reactor in a simultaneous saccharification and fermentation(SSF) mode using liquefied sago starch as a substrate. It was found that this process eliminated product inhibition and reverse reaction of glucose enhancing the rate of saccharification and ethanol production. At a low dilution rate of D = 0.11 hr$^{-1}$, the steady-state ethanol concentration was 46.0g/$m\ell$ (96.8 % of theoretical yield). The maximum ethanol productivity was 17.7g/$m\ell$, h at D = 0.83 hr$^{-1}$ when the calculation was based on the total working volume. The continuous production of ethanol was maintained stably over 40 days without problems in this reactor system.

전분으로부터 동시당화 발효법에 의한 에탄을 생산공정의 개발을 위하여 amyloglucosidase를 chitin 에 결합시킨 후 Zumomonas mobilis와 함께 sodium alginate젤에 재고정화 시킨 다음 에탄을 생산실험을 행한 결과 전분의 당화 및 발효속도를 증가시킬 수 있음이 발견되었다. 충진층 발효조를 사용한 연속식 에탄올 생산결과 40일 이상 안정하게 유지할 수 있었고, 최대 에탄올 생산성은 희석배율 0.83$hr^{-1}$에서 17.7g/$\ell$, h였다.