产右旋糖酐肠膜明串珠菌发酵培养基的优化

旨在提高肠膜明串珠菌Leuconostoc mesenteroides CICC-23614发酵蔗糖产右旋糖酐的效率。以单因素实验为基础,以蔗糖、细菌蛋白胨、Na₂HPO₄·12H₂O及KH₂PO₄浓度作为影响因子,以蔗糖转化率为响应值,采用响应面分析法对肠膜明串珠菌培养基中各成分浓度条件进行研究,利用高效液相色谱法(HPLC)对发酵液中的蔗糖进行定量分析,优化得到最佳发酵培养基。结果显示,经过优化的最佳的培养基为:蔗糖101.31 g/L,细菌蛋白胨5.66 g/L,Na₂HPO₄·12H₂O 1.11 g/L和KH₂PO₄0.15 g/L。以优化后的培养基进行发酵,重复试验验证,发酵24 h,蔗糖转化率可达91.9%,与预测值误差仅为2.13%,相较于原始培养基发酵结果,蔗糖转化率是原始培养基培养条件下的1.6倍。

Optimization of Fermentation Medium for Producing Dextran from Leuconostoc mesenteroides

This paper aimed to improve the fermentation efficiency of dextran production with Leuconostoc mesenteroides CICC-23614. Based on the single factor optimization experiment,taking concentration of sucrose,peptone,Na₂HPO₄·12H₂O and KH₂PO₄ as the influencing factors and the sucrose conversion rate as response value,the concentration conditions of various components in the culture medium of Leuconostoc mesenteroides were investigated by response surface experiment. The sucrose concentration was analyzed by high performance liquid chromatography. The results showed that the optimal medium components were sucrose of 101.31 g/L,peptone of 5.66 g/L,Na₂HPO₄·12H₂O of 1.11 g/L and KH₂PO₄ of 0.15 g/L. Through verified trials with optimized medium,the sucrose conversion rate was 91.9% after 24 h of fermentation,the error with the predicted value was only 2.13%,which was 1.6 times than that of the control medium.