摘要

    作为将抗生素抗性基因（ARG）传播到环境中的主要“热点”之一，次级污水已引起了广泛的关注。但是，常规的消毒方法可能不足以成功去除ARG。因此，本研究使用银杏修饰的纳米零价铁活化的过硫酸钠研究了二次废水中十种ARGs的去除效率和再生潜力。此外，当通过过硫酸盐处理（PT）去除ARG时，细菌群落的作用尚不清楚。因此，定量PCR和Illumina MiSeq测序被用于进一步的探索。结果表明，在10分钟内去除了98.6％的细菌16S rRNA基因。 PT 0.5h后，目标ARGs的去除效率按以下顺序降低：Tn916 / 1545 = aac（低于检测限）> int I1（99.99％）> tet E（99.64％）> mex F（99.10％） > tet W（94.57％）> qnr S（90.18％）> van G（82.21％）> bla-TEM（64.15％）> cat A1（23.13％）。即使在储存48小时后，ARG的丰度也是稳定的。 pH值对ARGs去除效率的影响不显着。热图和主坐标分析结果表明，植物群落的丰富度并没有随着群落结构的变化而增加。这项研究表明PT是一种有效的方法，可以减少ARGs的含量。细菌携带的ARG不会在其宿主中繁殖并进一步传给其他细菌种群。

    Secondary effluents as one of the main ‘hotspots’ of spreading antibiotic resistance genes (ARGs) into the environment have attracted considerable attentions. However, conventional disinfection methods may be inadequate for the successful removal of ARGs. Therefore, this study investigated the removal efficiency and the regeneration potential of ten ARGs in secondary effluent using sodium persulfate activated by Ginkgo biloba L. modified nanoscale zero-valent iron. Moreover, the role of bacterial community was not yet clear when ARGs were removed by persulfate treatment (PT). Therefore, quantitative PCR and Illumina MiSeq sequencing were applied for further exploration. The results depicted that 98.6% bacterial 16S rRNA gene was removed within 10 min. After 0.5 h PT, the removal efficiency of target ARGs decreased in the following order: Tn916/1545 = aac (below the limit of detection) > int I1 (99.99%) > tet E (99.64%) > mex F (99.10%) > tet W (94.57%) > qnr S (90.18%) > van G (82.21%) > bla-TEM (64.15%) > cat A1 (23.13%). Even upon after 48 h storage, ARGs abundances were stable. The influence of pH on ARGs removal efficiency was not significant. The results of heatmap and principal coordinate analysis depicted that the abundance of ARGs did not increase with the changes of community structure. This study revealed PT as an effective method could reduce abundance of ARGs. The ARGs carried by bacteria did not multiply in their hosts and pass on to other bacterial populations further.

    https://www.sciencedirect.com/science/article/abs/pii/S1385894719312458