氯苯降解菌的筛选鉴定及降解特性研究

Isolation and Characterization of Chlorobenzene Degrading Bacteria

摘要:

本文采集化工厂排污口的污泥样品, 在含有氯苯为唯一碳源的基本培养基中, 先后分离筛选出7株能够降解氯苯的微生物菌株。通过对分离菌株的16S rRNA基因序列进行分析, 发现其中5株细菌分别属于放线菌目的考克氏菌属(KD139)、红球菌属(KD140和KD142)和节杆菌属(KD230和KD232), 1株细菌属于杆菌目的芽胞杆菌d属(KD178), 另外1株细菌属于黄色单孢菌目的寡食单胞菌属(KD237); 同时我们构建了系统进化树, 确定分离菌株的相对进化地位。本文还利用气相色谱方法, 对分离菌株降解氯苯的能力进行了初步分析, 其中寡食单胞菌KD237降解氯苯能力最高, 24 h内氯苯分解率达60.78%。

Abstract:

In this study, we isolated and characterized chlorobenzene degrading bacteria from the effluent and sludge samples of one chemical plant. Minimal medium supplemented with chlorobenzene as sole carbon source was used during the enrichment and domestication process. Seven major bacterial isolates were obtained and purified. Their 16S rRNA genes were amplified by PCR for sequencing and their identities were determined with homology comparisons. Five of the seven isolates belong to Actinomycetales including Kocuria KD139, Rhodococcus KD140, Rhodococcus KD142, Arthrobacter KD230, and Arthrobacter KD232; one is classified as Bacillus d KD178; and another one as Stenotrophomonas KD237. The phylogenetic tree was also constructed based on the analysis of 16S rRNA gene sequences. Chloro- benzene concentrations were quantified with gas chromatography to investigate the bio-degradation rates of the isolated strains. Stenotrophomonas KD237 degraded 60.78% chlorobenzene in the minimal medium within 24 h.