葡萄糖和木糖双底物生物合成2,3-丁二醇的条件优化

针对利用葡萄糖和木糖合成2,3-丁二醇的Klebsiella pneumoniae XJ-Li菌，优化培养基组成与发酵条件，围绕五、六碳糖共代谢的特点，探讨简单可行的代谢调控方法. 结果表明，60 g/L葡萄糖和40 g/L木糖为碳源，5.75 g/L NH4H2PO4为氮源，pH值维持在5.5，培养温度38℃, 2,3-丁二醇浓度可达19.24 g/L. 确定了pH值调控和外源添加维生素C的调控方式，通过调节发酵过程中pH值于5.5左右，使2,3-丁二醇的产量提高了16.4%；添加60 mg/L维生素C调节培养基的氧化还原状态，可使2,3-丁二醇的产量提高44.3%，批式发酵48 h, 2,3-丁二醇终浓度可达33.47 g/L.

Optimization of Cofermentation of Glucose and Xylose for Sythesis of 2,3-Butanediol

The production conditions of 2,3-butanediol by Klebsiella pneumoniae XJ-Li from glucose and xylose were optimized, and the regulation methods for 2,3-butanediol fermentation were also determined based on the metabolic features of hexose and pentose. The results displayed that suitable culture conditions were defined as glucose of 60 g/L, xylose of 40 g/L, ammonium dihydrogen phosphate of 5.75 g/L and pH of 5.5, and the concentration of 2,3-butanediol reached 19.24 g/L under the conditions when the strain was cultured at 38℃. The yield of 2,3-butanediol was increased by 16.4% after maintaining the pH about 5.5 in the fermentation process. And 60 mg/L of vitamin C was added into medium to regulate the redox state of system, which made the yield of 2,3-butanediol improved by 44.3% of 2,3-butanediol fermentation. 33.47 g/L of 2,3-butanediol was obtained in batch fermentation for 48 h under optimum culture conditions.