吡啶高效降解混合菌的筛选、鉴定、条件优化及其固定化

Isolation,Identification,Condition Optimization and Immobilization of Pyridine-Degrading Mixed Bacteria

[目的]分离筛选吡啶高效降解菌,降低吡啶废水生化处理成本。[方法]从生化池活性污泥中分离筛选能以吡啶为唯一碳源的高效降解菌,通过生理生化、形态特征、16S r DNA鉴定及序列分析确定菌株特性和种属。进行混菌组合及固定化试验,筛选最佳固定化材料。[结果]筛选出2株吡啶高效降解菌,分别命名为BD1、BD2,鉴定为克雷伯氏菌。[结论]在吡啶质量浓度100 mg/L条件下,BD1与BD2菌液配比为2∶1(P7)对吡啶的降解率达到了100%。正交试验确定P7降解吡啶的最佳环境条件组合为吡啶质量浓度150 mg/L、盐浓度1%、pH值7.0、温度30℃,组合纤维生物填料对混合菌P7的挂膜效果最好,能提高菌株对吡啶的降解效率及其稳定性。

[Aims]This study aims to isolate and screen out high-efficiacy degrading bacteria for pyridine to reduce the biochemical treatment cost of pyridine wastewater.[Methods]The high-efficacy degrading bacteria that can use pyridine as the sole carbon source was isolated and screened out from the activated sludge in the biochemical pond,and the characteristics and species of the strains was determined through physiological,biochemical and morphological characteristics,16 S r DNA identification and sequence analysis.The mixed bacteria combination and immobilization experiments were performed to screen out the best immobilized materials.[Results]Two strains of pyridine degrading bacteria were screened out,named BD1 and BD2 respectively,and they were identified as Klebsiella.[Conclusions]Under the condition of pyridine concentration of 100 mg/L,the degradation rate of pyridine reached100%when the ratio of BD1 to BD2 was 2∶1(P7).Orthogonal experiments determined that the best combination of environmental conditions for P7 to degrade pyridine is pyridine concentration 150 mg/L,salinity 1%,pH=7.0,temperature 30℃.The combined fiber biological filler has the best effect on the film formation of mixed bacteria P7,and it can improve the pyridine degradation efficiency and stability of the strains.