克雷伯氏菌胞外多糖发酵条件的优化研究

摘要

[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0.50g/L,牛肉膏0.50g/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50h.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 con ditions. [ Result] The results were showed as follows: 10 x salt solution (containing Na2HPO4 100.00 g/L, FeSO4 · 7H2O 0.01 g/L, MgSO4 ·7H2O2.00g/L, CaCl2 -2H2O 0.01 g/L, KH2PO4 30.00 g/L, K2SO410.00 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. [ Con clusion ] The study provides a technological basis for the batch production of bio-oligosaccharides in future.