동시고정화된 Amyloglucosidase와 Zymomonas mobilis를 이용한 전분으로부터의 Ethanol 생산

Abstract

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 0.83hr-1에서 17.7g/ℓ, h였다.

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/㎖ (96.8 % of theoretical yield). The maximum ethanol productivity was 17.7g/㎖, 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.