休哈塔假丝酵母HDYXHT-01利用木糖生产乙醇的发酵工艺优化
2011-09-29葛菁萍刘国明杨晓峰孙红兵凌宏志平文祥
葛菁萍,刘国明,杨晓峰,孙红兵,凌宏志,平文祥
黑龙江大学生命科学学院 微生物黑龙江省高校重点实验室,哈尔滨 150080
休哈塔假丝酵母HDYXHT-01利用木糖生产乙醇的发酵工艺优化
葛菁萍,刘国明,杨晓峰,孙红兵,凌宏志,平文祥
黑龙江大学生命科学学院 微生物黑龙江省高校重点实验室,哈尔滨 150080
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。
休哈塔假丝酵母,木糖,乙醇,响应面分析法
Abstract: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)2SO41.73 g/L, KH2PO43.56 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 thisfermentation conditions, ethanol productivity was 26.18 g/L, which was 1.15 times of the initial.
Keywords:Candida shehatae, xylose, ethanol, response surface methodology
燃料乙醇作为一种安全、清洁的可再生代用燃料的出现,在一定程度上缓解了当今的石油资源危机,己经引起世界各国的高度关注。传统的乙醇发酵工业主要以糖质和粮食类淀粉质为原料,而中国作为人口大国,粮食原料的供应受到很大限制而且成本过高[1],因此,以木质纤维素类资源为原料代替粮食进行乙醇发酵,具有十分重要的现实意义[2-3]。木糖是木质纤维原料水解产物中含量仅次于葡萄糖的一种单糖,含量可达到木质纤维水解糖类的35%以上[4]。木糖的乙醇发酵一直被人们视为木质纤维原料生物转化生产乙醇的关键因素,适宜的木糖发酵产率和乙醇浓度可以降低工艺总成本的 25%以上[5],因此提高木糖的乙醇发酵产率是该技术商业化生产的必要条件。……
