氯霉素降解菌的筛选与降解性能

Isolation and characterization of Chloramphenicol-degradation bacterial strains

目的从被氯霉素污染的南明河水中定向筛选高效降解氯霉素的菌株,并初步探讨其降解特性,为水体中氯霉素污染的微生物处理提供有效的菌源与理论依据。方法采用选择性富集培养、划线分离筛选降解菌,观察其形态,进行生化鉴定确定其种属;并用培养技术和液质联用仪检测菌株对底物氯霉素的利用和降解情况。结果从南明河水样中定向筛选到2株氯霉素降解菌,分别为嗜水气单胞菌和恶臭假单胞菌;在氯霉素的初始浓度为50μg/L的无机盐培养液中,经两周降解试验,嗜水气单胞菌对氯霉素去除率为13.79%,而恶臭假单胞菌对氯霉素去除率为89.54%。结论筛选出的恶臭假单胞菌对氯霉素有较高并且稳定的降解能力,具有潜在的应用价值。

Objective This study aimed to isolate,screen,identify and characterize chloramphenicol-degrading bacteria from the water samples of chloramphenicol-contaminated Nanming River,then to provide valuable bacterial resource and theoretical basis for biological treatment of chloramphenicol-contaminated water. Methods Degrading bacteria were isolated by selective-enrichment culture and streak plate method. They were identified by morphological observation,physiological and biochemical properties analysis. Cultivating technique and high performance liquid chromatography-mass spectrometry method were used to determine the degrading of chloramphenicol. Results Aeromonas hydrophila and Pseudomonas putida were isolated from the water samples in Nanming River. The chloramphenicol removal rates of Aeromonas hydrophila and Pseudomonas putida were 13. 79%and 89. 54% after two weeks,respectively,while the initial concentration of chloramphenicol was 50 μg/L in mineral medium. Conclusion This indicated that Pseudomonas putida have higher degradation and stability ability for chloramphenicol,and hold the potential of being applied in treatment of water-containing chloramphenicol.