Characters of Ethanol Producing Candida intermedia Yeast in Xylose Fermentation / 微生物学通报

Characters of one Candida intermedia yeast strain which isolated from nature can produce ethanol from xylose-fermenting been systemic studied. In conditions 28?C, 120 r/min, 72 h, it can produce 6.480 g/L ethanol from 7% xylose and 43.70% theoretical production of ethanol from 3% xylose. It can produce up to 21.225 g/L ethanol when incubation time prolong to 156 h from 8% xylose. It also can ferment 13% glucose produce 47.647 g/L ethanol and reach 76.90% of theoretical ethanol production, respectively. Compared to CK, ethanol productivity can be improved 9.91% when add 8% xylose in three times as 3%, 2% and 3%, respectively. Glucose can be first utilized in the mixture sugar medium. When the ratio of xylose vs. glucose is 3:1in mixture sugar, the productivity of ethanol can be improving 25%.

Study on Optimization of Soybean Meal Solid Fermentation Process by Response Surface Analysis / 中国生物工程杂志

Response surface analysis (uniform precision of central composite design, SAS 9.1.3 software) was applied to optimize the four major factors (ratio of soybean meal to water, enzyme quantity, fermentation time and inoculation quantity) for soybean meal solid fermentation. According to the change of the hydrolyzation degree of soybean protein, the equation of polynomial regression was established between those factors and the response. The result showed that the optimum condition included as follows: ratio of soybean meal to water 1∶1.00,enzyme quantity 2.55%, fermentation time 65h and inoculation quantity 1.00%. Under the optimum level, the degree of hydrolyzation reached 13.3%, which increased 56% over pre-optimization.

Production of High Ethanol Concentration from Raw Corn Flour Using Rhizopus sp. and Saccharomyces cerevisiae / 微生物学通报

A novel raw-starch-digesting glucoamylase producer,Rhizopus sp.W-08,was used in a novel fermentation system of solid-state followed by submerged,and high enzyme activity of 72 IU/mL was obtained.In the following simultaneous saccharification and fermentation process, Saccharomyces cerevisiae Z-06 directly converted raw corn flour to ethanol with the concentration of 21 % (V/V) at 30℃ after 48h.The conversion efficiency of raw corn flour to ethanol was 94.5 % of the theoretical ethanol yield.