季也蒙毕赤酵母MCJ-1培养条件优化及其冻干菌粉的制备

Optimization of culture conditions of Pichia guilliermondii MCJ-1 and preparation of freeze-dried yeast powder

康普茶是一种酸甜味发酵饮料,由酵母、糖和发酵茶制成。该研究以从康普茶混菌体系中筛选获得的季也蒙毕赤酵母(Pichia guilliermondii)MCJ-1为研究对象,采用单因素试验及响应面法优化菌株MCJ-1的培养条件,并制备其冻干菌粉。结果表明,菌株MCJ-1的最佳培养条件为:蔗糖25.00 g/L,氯化铵7.7 g/L,蛋白胨10.00 g/L,酵母浸粉5.00 g/L,培养温度30℃,初始pH值为6,转速200 r/min。在此优化培养条件下,菌体干质量为(5.06±0.22)mg/mL,比优化前提高了64.82%。菌粉制备中菌泥与保护剂的比例为1:1,保护剂甘油添加量为4.0%,可以获得存活率达(80.83±5.36)%的冻干菌粉。

Kombucha is a sour and sweet fermented beverage made from yeast,sugar and fermented tea.Using Pichia guilliermondii MCJ-1 screened from the mixed microbe system of Kombucha as the research object,the culture conditions of strain MCJ-1 were optimized with single factor experiments and response surface methodology,and the freeze-dried powder was prepared.The results showed that the optimized culture conditions of the strain MCJ-1 were as follows:sucrose 25.00 g/L,ammonium chloride 7.7 g/L,peptone 10.00 g/L,yeast extract 5.00 g/L,culture temperature 30℃,initial pH 6,and rotation speed 200 r/min.Under the optimal culture conditions,the dry mass of the strain MCJ-1 was(5.06±0.22)mg/ml,which was 64.82%higher than that before optimization.In the preparation of yeast powder,the ratio of yeast mud and protective agent was 1:1,and the glycerin of protective agent addition was 4.0%,the survival rate of freeze-dried yeast powder was(80.83±5.36)%.