营养因子对干酪乳杆菌LC2W胞外多糖合成的影响

Effects of nutrition factors on the exopolysaccharide production by Lactobacillus casei LC2W

针对影响干酪乳杆菌LC2W产胞外多糖的主要营养因子:葡萄糖、酪蛋白胨和酵母提取物进行了单因素及正交试验,确定了合成胞外多糖的最适组成为葡萄糖60 g/L,酪蛋白胨16 g/L,酵母提取物10 g/L,其中酪蛋白胨影响差异极显著。验证试验表明,以优化后的培养基进行发酵试验,37℃培养24 h,所得胞外多糖量为120.37 mg/L,较原来提高67.97%。

The effects of three main nutrition factors on exopolysaccharide production by Lactobacillus casei LC2W were studied. Medium components were optimized by means of single factor test and orthogonal experiments. The results showed that the most important component influencing the yield of exopolysaccharide was the concentration of casein tryptone in the medium. The optimized medium was composed of glucose 60 g/L, casein tryptone 16 g/L, yeast extract 10 g/L. Cultured at 37℃ for 24 h, the maximum yield of exopolysaccharide by Lactobacillus casei LC2W strain in the optimized medium could reach 120.37 mg/L, which was increased by 67.97% compared with those in the commecial MRS broth.