休哈塔假丝酵母发酵木糖制乙醇过程研究

Process of Xylose Fermentation by Candida shehatae to Produce Ethanol

木质纤维素原料水解产物的主要成分是葡萄糖和木糖,其中葡萄糖很容易发酵,致使木糖成为木质纤维素发酵的关键,休哈塔假丝酵母(Candida shehatae)1766是自然界木糖发酵性能较好的天然酵母之一。研究了发酵温度、发酵时间、接种量、初始pH值、摇床转速等因素对休哈塔假丝酵母1766发酵木糖生产乙醇的影响,由正交试验初步确定了休哈塔假丝酵母发酵木糖制乙醇工艺的适宜条件为好氧条件,发酵时间为2d,发酵温度为28℃,摇床转速为150r/min,初始pH值为5,此时乙醇收率最高可达68.62%。

The basis of lignocelluloses hydrolysate is xylose and glucose,and glucose can be ferment quite easy,so xylose fermentation is the key factor for lignocelluloses fermentation.Candida shehatae is one of the best xy-lose-ferm enting yeast in nature.In this study,the influence of fermentation temperature,fermentation time,the capacity of inoculation,initial pH and rotating speed on xylose fermentation by Candida shehatae（Candida shehatae）1766 to produce ethanol were investigated.The superior fermentation conditions of the xylose ferment to ethanol by Candida shehatae were studied by the orthogonal experiment.The optimal conditions were as follows,aerobiosis,fermentation time 2 days,fermentation temperature at 28℃,rotating speed at 150 r/min,and initial pH value as 5.0.Under this conditions,the yield of ethanol can reach 68.62%。