乳酸链球菌冻干保护剂的筛选和优化

摘要

通过采用9因素2水平Plackett-Burman设计法,对可溶性淀粉、蔗糖、甘油、大豆粉、海藻糖、甘露醇、明胶、甘氨酸和谷氨酸钠9种材料对乳酸链球菌的保护效果进行评价.结果表明:乳酸链球菌的有效冻干保护剂是大豆粉、蔗糖、甘油和甘露醇.通过正交试验设计确定最优冻干保护剂的配方组合和用量,即大豆粉10％、蔗糖10％、甘油3％和甘露醇0.8％(均为质量分数),经过多次实验证明最优保护剂配方组合能使乳酸链球菌的冻干存活率达到77.85％.%Plackett-Burman design was used to evaluate the freeze-drying protective effect of solublestarch, sucrose, glycerol, soybean meal, tre-halose, mannitol, gelatin, glycine and sodium glutamate for streptococcus lactis. The results indicated that the soybean meal, sucrose, glycerol and mannitol were four key factors, which contributed to the survival of the cells after cryodesiccation. The components and dosage of the cryoprotective agents were determined by orthogonal experiment design.The optimal formula was obtained as: soybean meal 10%, sucrose 10%, glycerol 3% and mannitol 0.8%, with which the cell survival rate reached 77.85% by many experiments.