啤酒酵母胞外多糖发酵条件的研究

Studies on fermentation conditions of excellularpolysaccharide produced by Saccharomyces cerevisiae

以啤酒酵母S - 12为出发菌株 ,用紫外线 +氯化锂作为复合诱变剂 ,获得一株产胞外多糖量较高的变株S - 12 - 4 ,比出发菌株提高 33.3%。同时对变株进行了最佳培养条件的研究 ,结果表明 :最适碳源和氮源分别为大米糖 3%、酵母粉 0 .37%及NH4 Cl 0 .32 % ,最适发酵条件为起始pH6.0、培养温度 2 6℃、发酵周期为 30h ,在此基础上进行培养 ,变株S - 12 - 4产胞外多糖最高可达38.2mg 10 0mL ,比初始条件提高了 5 4 %。

A high-producing strain of excellular polysaccharide, S-12-4, was obtained by mutation with UV & LiCl and its production was 33% higher than that of the original strain Saccharomyces cerevisiae S-12. The optimal fermentation conditions were studied. The results showed that the optimal medium consists(%): saccharide from rice 3, yeast powder 0.37 and NH 4Cl 0.32. The optimal fermentation conditions were: the initial pH6.0, temperature 26℃ and fermentation for 30h. The highest production of polysaccharide was up to 38.2mg/mL, which was 54% higher than that of the initial.