聚β-羟基丁酸高产菌株的选育及发酵条件优化

Screening of Mutants and Optimization of Fermentation Conditions for Poly-β-hydroxybutyrate-Producing Strain

以分离筛选到的1株产PHB的蜡状芽孢杆菌13及其经紫外诱变获得的高产菌13(3)为出发菌株,再进行紫外和亚硝酸双因子诱变,筛选到了稳定高产菌株13-2,其PHB产量比野生型菌株13增加了82.63%,比高产菌株13(3)增加了48.01%。设计正交试验。确定突变株13-2培养的最佳发酵条件是碳源为蔗糖,氮源为蛋白胨,p H值为7.5,发酵温度为37℃,发酵周期为16h。

The wild type strain 13 and mutant 13 （3） of Bacillus cereus were treated by UV and HNO2 mntagenesis. The high - yielding mutant 13 - 2 was screened. The PHB yield of the mutant 13 - 2 was increased by 82.63% than the wild type strain 13, and increased by 48.01% than the mutant 13 （3）. The optimum fermentation conditions for the mutant 13 -2 were researched by the orthogonal test. The results shown, the optimum fermentation conditions for the mutant 13 -2 were that carbon source was sucrose, nitrogen source was protein peptone, pH value of 7.5, the fermentation temperature for the 37 ℃, fermentation period was 16h.