休哈塔假丝酵母HDYXHT-01利用木糖生产乙醇的发酵工艺优化

Optimization of xylose fermentation for ethanol production by Candida shehatae HDYXHT-01

采用Plackett-Burman(PB)方法和中心组合设计(Central composit design,CCD)对休哈塔假丝酵母Candida shehatae HDYXHT-01利用木糖发酵生产乙醇的工艺进行优化。PB试验设计与分析结果表明:硫酸铵、磷酸二氢钾、酵母粉和接种量是影响木糖乙醇发酵的4个关键因素,以乙醇产量为响应目标,采用CCD和响应面分析法(Response surface methodology,RSM),确定了木糖乙醇发酵的最佳工艺为:硫酸铵1.73 g/L、磷酸二氢钾3.56 g/L、酵母粉2.62 g/L和接种量5.66%,其他发酵条件为:木糖80 g/L,MgSO4.7H2O 0.1 g/L,pH 5.0,培养温度30℃,装液量100 mL/250 mL,摇床转速140 r/min,发酵时间48 h,在该条件下发酵液中乙醇产量可以达到26.18 g/L,是优化前的1.15倍。

Plackett-Burman（PB） design and central composite design（CCD） were applied to optimize of xylose fermentation for ethanol production by Candida shehatae HDYXHT-01.The PB results showed that（NH4）2SO4,KH2PO4,yeast extract and inoculum volume were the main affecting factors.With ethanol productivity as the target response,the optimal fermentation was determined by CCD and response surface analysis（RSM）.The optimal fermentation conditions were（NH4）2SO4 1.73 g/L,KH2PO4 3.56 g/L,yeast extract 2.62 g/L and inoculum volume 5.66%.Other fermentation conditions were xylose 80 g/L,MgSO4.7H2O 0.1g/L,pH 5.0 and 250 mL flask containing 100 mL medium and cultivated at 30 °C for 48 h and the agitation speed was 140 r/min.Under this fermentation conditions,ethanol productivity was 26.18 g/L,which was 1.15 times of the initial.