产胞外谷胱甘肽酿酒酵母的诱变选育及发酵优化

Breeding and Fermentation Optimization of Saccharomyces Cerevisiae Producing Extracellular Glutathione

为获得一株能产胞外谷胱甘肽(glutathione,GSH)的突变株,对酿酒酵母GAQ4进行紫外迭代诱变处理,最终筛选得到突变菌株UV3-10,其胞外谷胱甘肽含量为18.56 mg/L,是出发菌株GAQ4胞外谷胱甘肽含量的2.52倍。为进一步提高胞外谷胱甘肽含量,通过单因素试验优化突变株UV3-10发酵条件,得到其最优摇瓶发酵条件为发酵周期48 h、发酵温度34℃、摇瓶转速140 r/min、摇瓶装液量75 mL/300 m L、初始pH值为6.5;优化后其胞外GSH含量达到52.05 mg/L,是发酵条件优化前胞外GSH含量的2.80倍。

To obtain a mutant strain that produces extracellular glutathione(GSH),Saccharmyces Cerevisiae GAQ4 was treated iteratively by UV mutagenesis,and a mutant strain named UV3-10 was finally screened after three times of UV mutagenesis. The extracellular GSH content of UV3-10 was 18.56 mg/L,which was 2.52 times that of original strain GAQ4. To further improve the extracellular GSH content,the fermentation conditions of mutant strain UV3-10 were optimized by single factor experiment. Results showed that the optimal fermentation conditions were 48 h fermentation cycle,fermentation temperature at 34 ℃,shake flask speed at 140 r/min,shake flask volume of 75 mL/300 mL,and initial pH of 6.5. Under these conditions,the extracellular GSH content reached 52.05 mg/L,which was 2.80 times of that before optimization,achieving the extracellular fermentation production of GSH.