鞘氨醇单胞菌发酵生产韦兰胶培养基优化研究

Optimization of fermentation medium for welan gum production by Sphingomonas sp.

韦兰胶是由鞘氨醇单胞菌(Sphingomonas sp.)分泌的一种可溶性胞外多糖。该研究以实验室保存的一株韦兰胶生产菌Sphingomonas sp.511的产胶率为指标,在单因素试验确定显著因素的基础上,通过最陡爬坡试验确定显著因素的较优水平,再经响应面法设计试验优化韦兰胶发酵培养基,得出韦兰胶最佳发酵培养基组成为葡萄糖35.5 g/L,豆粕6.3 g/L,K_2HPO_4 2.4 g/L,在此条件下韦兰胶的产胶率达24.87 g/L。

Welan gum is a kind of soluble exopolysaccharide secreted by Sphingomonas sp. In this paper, using the gum production rate of gum-producing strain Sphingomonas sp. 511 as evaluation index, on the basis of single factor experiment, the optimal levels of significant factors were determined by the steepest ascent experiment, and then the gum fermentation medium composition were optimized by response surface methodology. Results showed that the optimal fermentation medium was glucose 35.5 g/L, soybean meal powder 6.3 g/L, K2HPO4 2.4 g/L, under this condition, the yield ofwelan gum reached 24.87 g/L.