少动鞘脂单胞菌产结冷胶发酵培养基的响应面法优化

通过单因素试验分析不同碳源、氮源、无机盐对（Sphingomonas paucimobilisFJAT-5627）产胶量的影响,确定最适碳源、氮源、无机盐,并在单因素筛选试验的基础上,利用Box-Benhnken设计和响应面分析法对碳源、氮源和无机盐进行优化,得到少动鞘脂单胞菌产生结冷肢发酵培养基最佳优化组合.实验结果表明,少动鞘脂单胞菌产胶量发酵最适碳源、氮源和无机盐分别为淀粉、豆饼粉和KH₂PO₄.响应面法得到产胶量（Y）与碳源淀粉（x₁）、氮源豆饼粉（x₂）和无机盐KH₂PO₄（x₃）的回归方程为:Y=13.87+0.54x₁+0.22x₂-0.42x₃-3.26x₁²-1.85x₂²-1.51x₃²+0.053x₁x₂+0.067x₁x₃+0.4x₂x₃.优化培养基组合为:淀粉浓度为30g/L,豆饼粉浓度为5 g/L,KH₂PO₄的浓度为0.7g/L,且此组合下少动鞘脂假单胞发酵得到结冷胶可达23.87g/L.

Optimization of Fermentation Culture Cedium for Producing Gellan Gum of Sphingomonas Paucimobilis by Response Surface Methodology

The effects of carbon source,nitrogen source,inorganic salt on the yield of gellan gum on the growth of Sphingomonas paucimobilis FJAT-5627 were studied by Singlefactor analysis in order for gaining the optimum carbon,nitrogen and inorganic salt.The fermentation culture of strain was optimized by Box-Benhnken design and the response surface methodology based on the single factor experiments.The results showed that the fittest carbon source,nitrogen source and inorganic salt were soluble starch,soybean cake and potassium dihydrogen phosphate（KH_2PO_4） respectively.The regression equation between the production of gellan gum（Y） and the variables from carbon source（x_1）,nitrogen source（x_2） and inorganic salt（x_3） by the response surface method were computed.The regression equation was Y = 13.87＋0.54x_1＋0.22x_2-0.42x_3-3.26x_1~2-1.85x_2~2-1.51x_3~2＋0.053x_1x_2＋0.067x_1x_3＋0.4x_2x_3.The optimal culture medium was as follows：30 g/L soluble starch,5g/L soybean cake and 0.7 g/L KH_2PO_4.The average yield of gellan gum reached to 23.87g/L after fermentation experiment under optimal condition.