响应面法优化嗜热厌氧杆菌X514产乙醇合成培养基  

Optimization of the Synthetic Medium Using RSM for Ethanol Production by Thermoanaerobacter sp. X514

作　　者：凌小芳[1] 谢天[2] 杨静[1] 

机构地区：[1]中国科学院青岛生物能源与过程研究所生物燃料重点实验室,青岛266101 [2]中国科学院成都生物研究所应用与环境微生物中心,成都610041

出　　处：《生物技术通报》2012年第8期168-174,共7页Biotechnology Bulletin

基　　金：国家自然科学基金项目(30800202);国家自然科学基金;留学回国人员科研启动基金;英国皇家学会双边交流合作项目(31011130157)

摘　　要：嗜热厌氧杆菌X514(Thermoanaerobactersp.X514)能同时发酵五碳糖、六碳糖并产出乙醇,是纤维素乙醇生产中最具潜力的菌株之一。单因子试验证明,酵母提取物中对X514乙醇发酵起决定性影响的组分为B族维生素,并进一步确定了B族维生素中对乙醇发酵有影响作用的6种维生素。结合培养基中的其他影响因子,应用Plackett-Burman试验设计方法,筛选出X514乙醇发酵的极大影响因子为NH4Cl、烟酸及硫胺素。随后用最陡爬坡试验确定了影响因子最佳取值区域,并利用响应面方法优化合成培养基。优化结果显示,当以5 g/L葡萄糖为底物时,在NH4Cl、烟酸及硫胺素的浓度分别为1.05 g/L、6.4 mg/L及7.0 mg/L的条件下,X514的乙醇产出浓度达到最优理论值34.46 mmol/L。试验验证该条件下乙醇产出浓度为33.78 mmol/L。试验值与理论值接近,原始矿物质培养基中乙醇产出浓度的5.1倍,并与添加5 g/L的酵母提取物培养基的乙醇产出浓度(34.67 mmol/L)相当。sp. X514 can ferment both xylose and pentose to ethanol, which is a promising strain to be applied into the cellulosic ethanol production. In the primary screening experiment, B family vitamins in yeast extract are found to be the main components contributing to the ethanol production. The further experiment reveals the most important six kinds of vitamins among B family vitamins. Together with three other factors, pH, NH4C1, MgC12 which contribute to the fermentation, totally nine variables are introduced in the medium optimization process. Further study with Plackett-Burman design reveals that among all factors in the synthetic medium, NH4C1, nicotinic acid and thiamine are critical to the ethanol production. By means of the steepest ascent experiment and the followed Response Surface Methodology （ RSM ） , it is found out that the fermentation can theoretically reach its maximum, when the concentrations of NH4C1, nicotinic acid and thiamine reach 1.05 g/L, 6.4 mg/L and 7.0 mg/L, respectively. Under the optimal condition, with 5 g/L glucose as the substrate, the predicted ethanol production is 34.46 mmol/L, in good agreement with the experimental production in the batch fermentation 33.78 mmol/L, which is about 5.1 times the original ethanol production of X514 in mineral medium.

关 键 词：CBP 嗜热厌氧菌 乙醇发酵 B族维生素 RSM 

分 类 号：TQ223.122[化学工程—有机化工]