摘要
在烟碱生物降解的研究和实际应用中,需要在较短的时间内获得大量O.intermediumDN2菌体。为了提高菌株DN2的菌体浓度,缩短其培养时间,本研究采用PlackettBurman设计对影响O.intermediumDN2生长的内在和外在相关因素进行了评价。结果表明,影响菌株DN2生长的显著因素有胰蛋白胨、MgSO4·7H2O、初始pH值、温度、装液量和培养时间。在此基础上,采用响应曲面法分别对该菌生长培养基的组成和培养条件进行优化,得到最佳培养基组成为(g/L):胰蛋白胨11.34、牛肉膏3.00、NaCl5.00、MgSO4·7H2O3.71,pH值7.23;最佳培养条件为温度32℃、转速120r/min、装液量88ml/250ml三角瓶、培养时间34h。5L发酵罐验证实验表明,菌株DN2达到最大生长量的时间为36h,与预测值34h基本一致,比优化前缩短约12h;最大菌体浓度为6.49×109cfu/ml,与预测值6.73×109cfu/ml接近,比优化前高近一个数量级。
Plackett-Burman design was used to evaluate importance of the selected fifteen internal and external factors to the growth of Ochrobactrum intermedium DN2. Results showed that tryptone, MgSO4 · 7 H2O, temperature, the initial pH value, volume of medium and incubation time were the main factors affecting the growth of strain DN2. In addition, the central composite design and response surface analysis were used to determine the optimal levels of the main factors. The optimized medium was determined as follows： tryptone 11. 34g/L, beef extract 3.00g/L, NaCl 5.00g/L, MgSO4.7 H20 3.71 g/L, pH 7.23. The optimal cultural conditions were cultural temperature, 32℃ ; rotatory speed, 120r/min ; volume of medium, 88ml/250ml Erlenmeyer and incubation time,34h. Under these conditions, cell density of strain DN2 can increase from 7.35 ×10^8cfu/ml to 6.49× 10^9cfu/ml and time used to obtain maximal cell production decreases from 48h to 36h. The experimental data have validated the theoretical values.
出处
《中国生物工程杂志》
CAS
CSCD
北大核心
2005年第11期41-46,共6页
China Biotechnology
作者简介
通讯作者，电子信箱：fmb@njau．edu．cn
