克雷伯氏菌胞外多糖发酵条件的优化研究

Optimization of Fermentation Conditions for Extracellular Polysaccharide Production of Klebsiella

[目的]对克雷伯氏菌(Klebsiella sp.)K13胞外多糖的发酵条件进行优化。[方法]通过单因素试验和正交试验对培养条件和培养基组成进行优化。[结果]胞外多糖制备的优化培养基组成为:10×盐溶液(含Na2HPO4 100.00 g/L,FeSO4.7H2O 0.01 g/L,MgSO4.7H2O 2.00 g/L,CaCl2.2H2O 0.01 g/L,KH2PO4 30.00 g/L,K2SO4 10.00 g/L,NaCl 10.00 g/L),葡萄糖30.00 g/L,蛋白胨0.50 g/L,牛肉膏0.50 g/L,油酸1.50 g/L。最佳发酵参数为:初始pH 7.0,发酵温度24℃,接种量10%,装液量200 ml/500 ml,培养时间50 h。优化后,其胞外多糖产量可达6.70 g/L。[结论]该研究可以为后期批量制备新型生物寡糖奠定技术基础。

[Objective] The medium compositions and environmental conditions were optimized in order to improve the yield of extracellular polysaccharide（EPS） of Klebsiella.[Method] The single factor experiment and the orthogonal test were used to optimize the fermentation conditions.[Result] The results were showed as follows： 10×salt solution（containing Na2HPO4 100.00 g/L,FeSO4·7H2O 0.01 g/L,MgSO4·7H2O 2.00 g/L,CaCl2·2H2O 0.01 g/L,KH2PO4 30.00 g/L,K2SO4 10.00 and NaCl 10.00 g/L）,glucose 30.00 g/L,peptone 0.50 g/L,beef extract 0.50 g/L and oleinic acid 1.50 g/L;the initial pH 7.0,culture temperature 24 ℃,inoculation size 10%,load volume of broth 200 ml/500 ml,and incubation time for 50 h.After the optimization,the yield of extracellular polysaccharide reached 6.70 g/L.[Conclusion] The study provides a technological basis for the batch production of bio-oligosaccharides in future.