积累PHB菌种隐藏嗜酸菌DX1-1的诱变改良

The Mutagenic Effect on PHB Accumulation of Acidiphilium cryptum DX1-1

摘要:

采用紫外线照射和放射性元素钴60辐射诱变方法, 对分离纯化的一株可积累聚β-羟基丁酸酯(PHB)的Acidiphilium cryptum DX1-1进行了诱变改良, 以获得PHB高产菌。结果显示钴60诱变最佳诱变剂量为100 Gy, 紫外诱变的最佳剂量为15 W、30 cm、60 s, 紫外诱变的效果比钴60诱变的效果好。诱变后筛选得到的一株菌UV60-3, PHB含量达到28.56 g/L, 是原菌株的1.45倍, 并且可稳定遗传。对菌株UV60-3积累PHB的碳氮比进行了探索, 结果显示在碳源浓度60 g/L, 氮源浓度30 g/L, C/N为3.76时PHB含量最高, PHB含量达到30.57 g/L。

Abstract:

The strain Acidiphilium cryptum DX1-1 producing PHB was irradiated respectively by UV and Co60 to raise PHB production. The results indicated that the effect of UV better than using Co60. One strain of the UV mutagenized called UV60-3 has the highest PHB production yield, showing final PHB concentration of 28.56 g/L, 1.45 times higher than that of original strain. FT-IR spectroscopy analysis shows that the polymers obtained from the strain DX1-1 have the same IR spectra of standard PHB. Further research about the best appropriate C/N ratio of the mutant was done. The optimum ratio of C/N was about 3.76, the final PHB concentration reaches to 30.57 g/L.