氯霉素对序批式反应器生物脱氮及微生物群落的影响探究

Effect of Chloramphenicol on Nitrogen Removal and Microbial Community in Sequencing Batch Reactor

为探究新型污染物氯霉素类抗生素对活性污泥生物脱氮的影响,构建了批式生物反应器,在中温条件下研究不同浓度氯霉素(CAP)对生物脱氮的影响。结果表明,CAP的存在抑制了脱氮效率,且当CAP的质量浓度为5.0mg/L时,氨氮(NH;-N)和总氮(TN)的去除率分别为81.3%和61.2%,仅为空白组的88.1%和77.9%。CAP存在提高胞外聚合物(EPS)的含量,且CAP质量浓度越高,EPS的含量提高越明显。CAP显著降低硝化与反硝化过程,降低氨氧化菌和亚硝酸盐氧化菌的活性。此外,CAP的质量浓度影响脱氮关键酶的活性,CAP质量浓度越高,脱氮关键酶抑制越明显。微生物分析表明,CAP存在降低Proteobacteria,Bacteroidetes及Chloroflexi的相对丰度。

In order to investigate the effects of new pollutants chloramphenicol antibiotics on biological nitrogen removal from activated sludge, batch bioreactors were constructed to investigate the effects of different concentrations of chloramphenicol(CAP) on biological nitrogen removal under moderate temperature conditions. The results showed that the presence of CAP inhibited the nitrogen removal efficiency, and when the concentration of CAP was 5.0 mg/L, the removal efficiency of ammonia nitrogen(NH;-N) and total nitrogen(TN) were 81.3% and 61.2%, respectively, which were only 88.1% and 77.9% of the blank group. The presence of CAP increased the content of extracellular polymers(EPS), and the higher the CAP concentration, the more significant the increase in EPS content. CAP significantly reduced the nitrification and denitrification processes, reducing the activity of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria. In addition, the concentration of CAP affected the activity of denitrification key enzymes. The higher the CAP concentration, the more obvious the denitrification key enzyme inhibition. Microbiological analysis showed that the presence of CAP reduced the relative abundance of Proteobacteria, Bacteroidetes and Chloroflexi.