苯酚高效降解菌群的群落结构及其代谢产物研究

Community structure of highly efficient phenol degrading bacteria and phenol metabolites

采用焦化厂好氧池活性污泥,通过分离筛选和驯化,成功得到了高效苯酚降解菌群(PDB),探究其对水相中苯酚降解的效果。结果表明,PDB菌群对苯酚的降解效果受底物质量浓度影响,当苯酚质量浓度低于700 mg/L时,苯酚降解率达到100%;当苯酚质量浓度增加至1300 mg/L时,降解率降至41.6%;当苯酚质量浓度高于1700 mg/L时,PDB菌群基本不能生长。通过高通量测序发现,PDB菌群物种丰富度较高,其中Proteobacteria、Firmicutes和Bacteroidota是优势门,Serratia sp.、Bacillus sp.和Muribaculaceae sp.是核心优势菌属。通过气相色谱-质谱联用(GC-MC)分析代谢产物可知,PDB菌群降解苯酚的路径是邻位开环裂解方式,产生酸性中间产物,随后分解为链状小分子物质。

By using activated sludge from the anaerobic tank of a coking plant,a highly efficient phenol-degrading bacterial(PDB)community was successfully obtained through separation and domestication,and its effect on micro⁃bial degradation of phenol was investigated.The results showed that the degradation effect of PDB community on phenol was affected by the substrate concentration.The degradation rate reached 100%when the phenol concentra⁃tion was lower than 700 mg/L.However,when the concentration of phenol increased to 1300 mg/L,the degradation rate decreased to 41.6%.When the concentration of phenol exceeded 1700 mg/L,the PDB community could basi⁃cally unable to grow.High-throughput sequencing revealed that the species richness within the PDB community was high.Proteobacteria,Firmicutes,and Bacteroidota were dominant phyla,while Serratia sp.,Bacillus sp.,and Murib⁃aculaceae sp.were core dominant genera of PDB.Metabolites analyzed by gas chromatography-mass spectrometry(GC-MS)revealed that the pathway for phenol degradation by PDB community was through ortho-cleavage,resulting in acidic intermediate products that subsequently decomposed into chain-like small molecular substances.