小型发酵罐条件下树干毕赤酵母木糖发酵条件优化

Optimization of ethanol fermentation conditions with xylose by Pichia stipitis in bioreactor

以树干毕赤酵母m4为发酵木糖菌株,研究了5L发酵罐中不同培养条件对酵母发酵木糖生成乙醇和酵母生长规律的影响。结果表明,5L发酵罐中最佳发酵条件为:初始木糖浓度108g/L,温度28℃,通气量30L/h,转速300r/min,接种量12.5%,最适pH值为4.8,此时木糖转化率、乙醇得率最高,分别为98.5%,0.47g/g,乙醇产量有较大提高,50.0g/L。

The effects of the different incubation conditions on the ethanol fermentation with xylose by Pichia stipitis m4 were studied. Growth of pattern of yeast and production of ethanol under different conditions in a 5L bioreactor were investigated. The results indicated that the optimum fermen- tation conditions in a 5L bioreactor were as follows： initial comem of xylose 108g/L, fermentation temperature at 28℃, ventilation level at 30L/h, the rotating speed 300r/min, inoculum 12.5%, pH 4.8. Under the optimum condition, rate of conversion of xylose to ethanol and yield of ethanol were 98.5% and 0.47g/g, respectively. Yield of ethanol significantly increased to 50.0g/L.