摘要
采用实验室分离的一株高产γ-聚谷氨酸枯草芽孢杆菌(T1B)通过响应面法筛选优化高产γ-PGA菌株冻干保护剂配方。通过单因素试验,确定脱脂奶10%(质量分数,下同)、蔗糖10%、麦芽糖10%为T1B菌株冻干保护剂最优单因素。然后以细胞存活率为响应值确定了T1B菌株复合冻干保护剂的最优配方为:脱脂奶粉浓度为7.39%,蔗糖浓度为9.60%,麦芽糖浓度为10.71%。优化后的冻干保护剂在冻干过程中对于T1B菌体保护效果显著,菌体存活率的理论值最大为83.8%。并确定菌体最佳离心条件为7000 r/min 5 min,复合冻干保护剂的最适pH为7.0,与菌体沉淀的最佳配比为2∶1,经验证此时菌体存活率为85.3%。
The formulation of a lyophilized protective agent for high-yieldγ-PGA strain was optimized by response surface method using a laboratory isolated strain of high-yieldγ-PGA Bacillus subtilis(T1B).Through a single factor test,it was determined that 10%skimmed milk,10%sucrose,and 10%maltose were the best single factors for the T1B freeze-dried protective agent.Then,based on the response value of the cell survival rate,the optimal formula of the T1B composite freeze-dried protective agent was determined:the concentration of skimmed milk powder was 7.39%,the concentration of sucrose was 9.60%,and the concentration of maltose was 10.71%.During the freeze-drying process,the optimized lyophilized protectant had a excellent performance on the bacterial protection of T1B,and the maximum theoretical value of bacterial survival rate was 83.8%.It was also determined that the best centrifugation condition of the bacteria is 7000 r/min in 5 min,the suitable pH of the composite freeze-dried protective agent is 7.0,and the best ratio of the bacteria mud is 2∶1,and the survival rate of the bacteria is 85.3%.
作者
陈斐
黄天悦
张旭松
曾鑫
郭佳强
陈孝平
CHEN Fei;HUANG Tianyue;ZHANG Xusong;ZENG Xin;GUO Jiaqiang;CHEN Xiaoping(School of Environmental Ecology and Bioengineering,Wuhan Institute of Technology,Wuhan 430205,China)
出处
《武汉工程大学学报》
CAS
2020年第6期610-615,共6页
Journal of Wuhan Institute of Technology
关键词
响应面法
高产γ-聚谷氨酸枯草芽孢杆菌
冻干保护剂
真空冷冻干燥
response surface method
high-producingγ-polyglutamic acid bacillus subtilis
freeze-drying protective additive
vacuum freeze drying
