摘要
      由于我们滥用抗生素，抗生素耐药性基因（ARGs）数量显著增加，这可能会对公众健康和环境造成严重危害。我们从医院废水中分离出6种不同的细菌，分别携带NDM-1、mcr-1和tetX三种最后的ARGs，研究了电化学（EC）处理的去除效率和去除机理。我们发现，ARGs的去除效率随着电压和电解时间的增加而增加，而最大去除效率可达90%。最佳处理电压和处理时间分别为3V和120min。温度、pH等因素对EC处理过程影响不大。通过扫描电子显微镜（SEM）和流式细胞仪从宏观和微观两个层面探讨了EC处理的机理。我们的结果表明，EC处理显著改变了细胞膜的通透性，导致细胞依次经历早期细胞凋亡、晚期细胞凋亡和细胞坏死。此外，与传统的消毒方法相比，EC处理的潜在风险较小。细胞的结合转移频率在处理后显著降低。不到1%的细菌进入存活但不可培养（VBNC）状态，不到5%的细胞内ARG（iARGs）转变为细胞外ARG（eARGs）。我们的发现为未来电化学处理去除医院废水中的ARB提供了新的见解和重要参考。
Abstract
The significant rise in the number of antibiotic resistance genes (ARGs) that resulted from our abuse of antibiotics could do severe harm to public health as well as to the environment. We investigated removal efficiency and removal mechanism of electrochemical (EC) treatment based on 6 different bacteria isolated from hospital wastewater carrying 3 last resort ARGs including NDM-1, mcr-1 and tetX respectively. We found that the removal efficiency of ARGs increased with the increase of both voltage and electrolysis time while the maximum removal efficiency can reach 90%. The optimal treatment voltage and treatment time were 3 V and 120 min, respectively. Temperature, pH and other factors had little influence on the EC treatment process. The mechanism of EC treatment was explored from the macroscopic and microscopic levels by scanning electron microscopy (SEM) and flow cytometry. Our results showed that EC treatment significantly changed the permeability of cell membrane and caused cells successively experience early cell apoptosis, late cell apoptosis and cell necrosis. Moreover, compared with traditional disinfection methods, EC treatment had less potential risks. The conjugative transfer frequencies of cells were significantly reduced after treatment. Less than 1% of bacteria entered the viable but nonculturable (VBNC) state and less than 5% of intracellular ARGs (iARGs) turned into extracellular ARGs (eARGs). Our findings provide new insights into as well as important reference for future electrochemical treatment in removing ARB from hospital wastewater.

https://www.sciencedirect.com/science/article/abs/pii/S0048969722004594