• Journal of Microbiology and Biotechnology
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• 제22권12호
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• pp.1673-1680
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• 2012

In this study, DEAE-corncobs [delignified corncob grits derivatized with 2-(diethylamino)ethyl chloride hydrochloride ($DEAE{\cdot}HCl$)] were prepared as a carrier to immobilize yeast (Saccharomyces cerevisiae) for ethanol production. The immobilized yeast cell reactor produced ethanol under optimized $DEAE{\cdot}HCl$ derivatization and adsorption conditions between yeast cells and the DEAE-corncobs. When delignified corncob grit (3.0 g) was derivatized with 0.5M $DEAE{\cdot}HCl$, the yeast cell suspension ($OD_{600}$ = 3.0) was adsorbed at >90% of the initial cell $OD_{600}$. This amount of adsorbed yeast cells was estimated to be 5.36 mg-dry cells/g-DEAE corncobs. The $Q_{max}$ (the maximum cell adsorption by the carrier) of the DEAE-corncobs was estimated to be 25.1 (mg/g), based on a Languir model biosorption isotherm experiment. When we conducted a batch culture with medium recycling using the immobilized yeast cells, the yeast cells on DEAE-corncobs produced ethanol gradually, according to glucose consumption, without cells detaching from the DEAE-corncobs. We observed under electron microscopy that the yeast cells grew on the surface and in the holes of the DEAE-corncobs. In a future study, DEAE-corncobs and the immobilized yeast cell reactor system will contribute to bioethanol production from biomass hydrolysates.

• 생명과학회지
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• 제22권4호
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• pp.508-515
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• 2012

Cotton을 효모 세포($Pichia$ $stipitis$)의 고정화 담체로 사용하기 위하여 2-(diethylamino)ethyl chloride hydrochloride (DEAE HCl)로 derivatization 시켰다. 0.5 M DEAE HCl로 처리하였을 때, 효모 세포가 완전히 흡착하였으며, 이것은 DEAE-cotton g 당 101.8 mg의 효모 세포가 흡착하는 것이고, DEAE-cellulose에 효모 세포가 흡착하는 양의 약 6배 이상인 것으로 확인되었다. DEAE-cotton을 이용하여 효모 세포를 고정화하고, 이것을 ethanol 생산에 이용하였을 경우, glucose와 xylose가 포함된 배지에서 단당류에 대한 ethanol 수율로 0.33 정도로 ethanol을 생산 할 수 있다는 것을 실험적으로 확인하였다. 이를 이용하여 lignocellulosic bomass의 가수분해물로부터 bioethanol 생산에 이용될 수 있을 것으로 기대되어진다. DEAE-cotton에서 얻어진 결과는 DEAE-cellulose에서 같은 실험을 실시하여 서로 비교 분석하였다.