Yuan Wenjie, Ren Jiangang, Zhao Xinqing, Bai Fengwu
Department of Bioscience and Bioengineering, Dalian University of Technology, Dalian 116023, China.
Sheng Wu Gong Cheng Xue Bao. 2008 Nov;24(11):1931-6.
A unique one-step ethanol fermentation process was developed with the inulinase-producing strain Kluyveromyces marxianus YX01. Firstly, the impact of temperature on ethanol fermentation was investigated through flask fermentation, and the temperature of 35 degrees C was observed to be the optimum to coordinate inulinase production, inulin saccharification and ethanol fermentation. And then, the impact of aeration and substrate concentration was studied through batch fermentation in the 2.5 L fermentor, and the experimental data indicated that the average ethanol fermentation time was decreased at the aeration rates of 50 mL/min and 100 mL/min, but higher ethanol yield was obtained under non-aeration conditions with more substrate directed to ethanol production. The ethanol concentration of 92.2 g/L was achieved with the substrate containing 235 g/L inulin, and the ethanol yield was calculated to be 0.436, equivalent to 85.5% of its theoretical value. Finally, Jerusalem artichoke grown in salina and irrigated with seawater was fermented without sterilization treatment, 84.0 g/L ethanol was obtained with the substrate containing 280 g/L dry Jerusalem artichoke meal, and the ethanol yield was calculated to be 0.405, indicating the Jerusalem artichoke could be an alternative feedstock for grain-based fuel ethanol production.
利用产菊粉酶的马克斯克鲁维酵母YX01菌株开发了一种独特的一步乙醇发酵工艺。首先，通过摇瓶发酵研究了温度对乙醇发酵的影响，发现35℃是协调菊粉酶产生、菊粉糖化和乙醇发酵的最佳温度。然后，通过在2.5 L发酵罐中进行分批发酵研究了通气和底物浓度的影响，实验数据表明，通气速率为50 mL/min和100 mL/min时，平均乙醇发酵时间缩短，但在非通气条件下，更多底物用于乙醇生产，乙醇产率更高。以含有235 g/L菊粉的底物实现了92.2 g/L的乙醇浓度，计算得到的乙醇产率为0.436，相当于其理论值的85.5%。最后，对生长在盐碱地并用海水灌溉的菊芋进行未经灭菌处理的发酵，以含有280 g/L干菊芋粉的底物获得了84.0 g/L的乙醇，计算得到的乙醇产率为0.405，表明菊芋可以作为基于谷物的燃料乙醇生产的替代原料。
