摘要

   芳香物质广泛存在于废水中，尤其是工业废水中，并可能导致废水处理生物反应器中大量的抗生素抗性基因（ARG）并刺激ARGs的水平转移。在这里，我们研究了一种实用的方法，该方法可应用臭氧预处理来减轻生物反应器中的ARG含量，从而处理含有典型芳香族污染物对氨基苯酚（PAP）的废水。结果表明，臭氧预处理可以有效降低废水的芳香性，与对照反应器相比，臭氧处理废水供入的生物反应器中ARGs的相对丰度降低了70％以上。在接受臭氧预处理的废水的生物反应器中，多药，喹诺酮，莫匹罗星，多粘菌素，氨基糖苷，糖肽，β-内酰胺和甲氧苄啶抗性基因都减少了。元基因组学分析表明ARGs的减少可能归因于细菌中ARGs和芳香族降解基因的共现。此外，我们扩展了分析范围，研究了来自不同环境的71个基因组，结果表明，芳香族化合物对ARG丰度的影响广泛存在于各种生态系统中，并证实了高含量的芳香族化合物可能导致ARGs的高丰度。综上所述，我们的工作证实了芳烃在选择ARGs中起着关键作用，并提出了一种减少废水处理生物反应器中ARGs的可行方法。

    Aromatic matters are widely present in wastewater, especially industrial wastewater, and may lead to a high abundance of antibiotic resistance genes (ARGs) in wastewater treatment bioreactors and stimulate horizontal transfers of ARGs. Here, we investigated a practical approach that applying ozone pretreatment to mitigate ARGs in bioreactors treating wastewater containing a typical aromatic pollutant, p-aminophenol (PAP). The results showed that ozone pretreatment could effectively reduce the aromaticity of wastewater, and the relative abundance of ARGs in the bioreactor fed with ozone treated wastewater decreased by over 70% compared to the control reactor. Multidrug, quinolone, mupirocin, polymyxin, aminoglycoside, glycopeptide, beta-lactam, and trimethoprim resistance genes were all reduced in the bioreactors receiving wastewater pretreated by ozone. Metagenomic analysis suggested that the reduction of ARGs could be attributed to the co-occurrence of ARGs and aromatic degradation genes in bacteria. Furthermore, we expanded our analysis to investigate 71 metagenomes from different environments, and the results indicated that the impact of aromatics on ARG abundance widely occurs in various ecosystems and confirmed that high levels of aromatics could lead to high abundance of ARGs. Taken together, our work confirmed that the aromatics played critical roles in selecting ARGs and proposed a feasible approach to reduce ARGs in wastewater treatment bioreactors.

    https://www.sciencedirect.com/science/article/pii/S0160412020318195