巨大芽孢杆菌NCT-2冻干菌剂的制备及冻干保护剂响应面优化

Preparation of Bacillus megaterium NCT-2 freeze- dried agent by using response surface methodology

摘要: 采用真空冷冻干燥法制备巨大芽孢杆菌NCT-2菌剂,采用单因素实验并用响应面方法对冻干保护剂配方进行了优化。以巨大芽孢杆菌NCT-2冻干存活率为考察因素,从离心浓缩条件、保护基质、保护剂筛选与复配、复水种类等方面探究影响。结果表明,离心条件为5000 r/min,10 min,选取新鲜培养基为保护基质时对巨大芽胞杆菌NCT-2冻干保护效果最佳。不同复水水质对菌体存活率无较大影响。当冻干保护剂浓度为:蔗糖4.51 mg/g、海藻糖0.90 mg/g、葡萄糖9.60 mg/g时冻干存活率最高,经验证存活率最高可达91.8%。

Abstract: Vacuum freeze-drying method was used to prepare B.megaterium NCT-2 agents,cryoprotectants were optimized using response surface methodology after single factor experiment.Centrifugal conditions,suspension substrate,selection and formulation of cryoprotectants,rehydration water were studied on the impact of survival rate.The results showed that the optimal conditions were 5000 r/min,10 min and fresh media was the better choice as the suspended substrate.Different kinds of water did not had obvious impact on the survival rate after rehydration.Results indicated the optimal amounts of cryoprotectants formula were sucrose 4.51 mg/g,trehalose0.9 mg/g,glucose 9.60 mg/g.The proven survival rate was 91.8%.