KSBB Journal

The Korean Society for Biotechnology and Bioengineering (한국생물공학회)
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Development of Glucoamylase & Simultaneous Saccharification and Fermentation Process for High-yield Bioethanol

고효율 바이오 에탄올 생산을 위한 당화효소 개발 및 동시당화발효 공정 연구

  • Choi, Gi-Wook (CHANGHAE Institute of Cassava and Ethanol Research, CHANGHAE ETHANOL CO., LTD.) ;
  • Han, Min-Hee (CHANGHAE Institute of Cassava and Ethanol Research, CHANGHAE ETHANOL CO., LTD.) ;
  • Kim, Yule (CHANGHAE Institute of Cassava and Ethanol Research, CHANGHAE ETHANOL CO., LTD.)
  • 최기욱 ((주)창해에탄올 창해연구소) ;
  • 한민희 ((주)창해에탄올 창해연구소) ;
  • 김율 ((주)창해에탄올 창해연구소)
  • Published : 2008.12.31
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Abstract

The bioethanol for use as a liquid fuel by fermentation of renewable biomass as an alternative to petroleum is important from the viewpoint of global environmental protection. Recently, many scientists have attempted to increase the productivity of bioethanol process by developing specific microorganism as well as optimizing the process conditions. In the present study, which is based on our previous investigation on the pretreatment process, theproductivity of bioethanol obtained from simultaneous saccharification and fermentation (SSF) process was compared between various domestic materials including barley, brown rice, corn and sweet potato. Additionally, Solid glucoamylase (SGA; developed in Changhae Co.), from modified strain with UV, was used. The result was compared to commercial glucoamylase (GA). It was observed that the fermentation rate was increased together with the yield which can be derived from the final ethanol concentration. Especially, in the case of brown rice, compared to the experimental results using GA, the final ethanol concentration was 1.25 times higher and 18.4 g/L of the yield was increased. Also, the time required for reaching 95% of the maximum ethanol concentration is significantly reduced, which is approximately 36 hours, compared to 88 hours using GA. It means that SGA has excellent saccharogenic power.

화석연료의 사용은 개발 한계성 및 고갈 그리고 지구온난화 등과 같은 심각한 문제를 지니고 있어 이를 극복하기 위해 환경 친화적이고 재생 가능한 바이오에탄올이 대두 대고 있다. 현재, 공정의 최적화와 미생물 개발을 통한 생산 단가를 낮추기 위한 많은 연구가 진행되고 있다. 본 연구에서는 쌀보리, 현미, 옥수수, 절간의 국내산 원료를 바탕으로 각각의 원료의 최적의 전처리 조건을 탐색하여 원료별 특성을 파악하여 동시당화공정발효를 이용하여 에탄올을 생산하였다. 또한 에탄올 생산성과 수율을 높이기 위하여 당화효소를 UV-mutation을 통해 개발한 SGA와 기존의 당화효소인 GA를 비교하였다. 그 결과 모든 원료에서 SGA가 GA보다 우수한 당화력을 나타내어 에탄올의 생산성과 수율을 향상 시켰다. 특히 가장 큰 차이를 보인 현미의 경우 에탄올 최대 농도가 1.25배 증가하여 18.4 g/L가 향상되었다. 또한 최대 농도의 95%도달시간을 비교해 본 결과 GA는 88시간, SGA는 35.98시간을 기록하였다. 이는 SGA의 당화력이 매우 우수함을 입증해준 결과라 할 수 있다.

Keywords

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