| Aromatic compounds including phenols and quinolines are major pollutants in industrial wastewater treatment. Microbial treatment can safely and efficiently remove these pollutants, the process of biological degradation mechanism including the structure of microbial flora, the function of key bacteria has become the research hotspot.In this study, molecular microbial ecology techniques and cultivation techniques were used to analyze the microbial flora in phenol and quinoline containing industrial wastewater treatment. The quinoline degrading capacity of microbial flora were examined by HPLC. Some key isolates were screened by hybridization and quinoline degradation capacity test, finally identified by 16S rDNA sequencing.The effect of phenol concentration on the structure and function of microbial communities, which were cultured in different conditions using coking wastewater biofilm as seeding, was investigated by Biolog and denaturing gradient gel electrophoresis (DGGE) methods. The less number of bands of cultivated samples on the denaturing gradient gel electrophoresis fingerprint of 16S rRNA gene indicated reduction of diversity after enrichment and cultivation. Some bands on the DGGE gel were significantly influenced by the phenol concentration in medium. The results of Biolog showed that the original biofilm sample had the highest substrate utility capacity as measured by average well color development (AWCD). But low concentration of Phenol enriched sample S7 showed more diverse activity on the utility of Carboxylic acids. The principal component analysis (PCA) of Biolog data revealed that the metabolic patterns were similar when using the same phenol concentration, although the sample S7 much less similar to other cultivated samples. These results suggested that the enrichment and cultivation with phenol supplemented decreased the diversity and also changed the metabolic function of the microbial community. Lower phenol concentration increased the microbial community metabolic activity. The phenol degrading capacity of isolates from each samples indicated that the enrichment and cultivation condition had changed the type and property of cultruable bacteria. Based on these results, we concluded that the different microorganisms will be isolated under different cultivation condition.The lab scale bioreactors treating quinoline-containing wastewater were acclimated using the coke wastewater treatment seeding sludge. It ran in denitrifying conditions and when it reached the stable stage, the average quinoline removal efficiency was above 90%. The community structures of the bioreactors were investigated by 16S rDNA clone library and 16S rRNA V3 454 sequencing methods after they reached steady-state. The cultivation and isolation of the bioreactor got 1212 isolates. After hybridization and quinoline degrading capacity test, 54 isolates were selected and sequenced.The results of 16S rDNA clone library and 16S rRNA V3 454 sequencing showedα-proteobacteria ,β-proteobacteria ,γ -proteobacteria,δ-proteobacteria,Actinobacteria and Bacteroidetes are the dominant group. Actinobacteria was the most dominant group of bacteria in denitrifying bioreactor. the Among them, The percentage of bacteria from genera Rhodococcus might be the main degraders of quinoline. Comparison of 16S rDNA clone library and 16S rRNA V3 454 sequencing, the result show the read lengths of 200 bases could recapture the same conclusions that would be drawn from the near-full length of 16S rDNA.When the fault occurred in reactor operation, quinoline content in effluent increased, but after regular running resumed for some time, the reactor can degrade quinoline efficiently and stabiligy again. The effluent and microbial community structure of reactor before failure and after were examined by HPLC and 16S rRNA V3 district 454 sequencing. The results showed that microbial reactor structure and the effluent are closely related.
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