Wang Siwen, Yang Shasha, Quispe Estefanny, Yang Hannah, Sanfiorenzo Charles, Rogers Shane W, Wang Kaihang, Yang Yang, Hoffmann Michael R
Linde+Robinson Laboratories, California Institute of Technology, Pasadena, California 91125, United States.
Department of Civil and Environmental Engineering, Clarkson University, Potsdam, New York 13699, United States.
ACS ES T Eng. 2021 Mar 12;1(3):612-622. doi: 10.1021/acsestengg.1c00011. Epub 2021 Mar 2.
Antibiotic resistance has become a global crisis in recent years, while wastewater treatment plants (WWTPs) have been identified as a significant source of both antibiotic resistant bacteria (ARB) and antibiotic resistance genes (ARGs). However, commonly used disinfectants have been shown to be ineffective for the elimination of ARGs. With the goal of upgrading the conventional UV disinfection unit with stronger capability to combat ARB and ARGs, we developed a UV-assisted electrochemical oxidation (UV-EO) process that employs blue TiO nanotube arrays (BNTAs) as photoanodes. Inactivation of tetracycline- and sulfamethoxazole-resistant along with degradation of the corresponding plasmid coded genes ( and ) is measured by plate counting on selective agar and qPCR, respectively. In comparison with UV irradiation alone, enhanced ARB inactivation and ARG degradation is achieved by UV-EO. Chloride significantly promotes the inactivation efficiency due to the electrochemical production of free chlorine and the subsequent UV/chlorine photoreactions. The fluence-based first-order kinetic rate coefficients of UV-EO in Cl are larger than those of UV irradiation alone by a factor of 2.1-2.3 and 1.3-1.8 for the long and short target genes, respectively. The mechanism of plasmid DNA damage by different radical species is further explored using gel electrophoresis and computational kinetic modeling. The process can effectively eliminate ARB and ARGs in latrine wastewater, though the kinetics were retarded.
近年来，抗生素耐药性已成为全球危机，而污水处理厂已被确认为抗生素耐药菌（ARB）和抗生素耐药基因（ARG）的重要来源。然而，已证明常用消毒剂对消除ARGs无效。为了升级传统的紫外线消毒装置，使其具有更强的对抗ARB和ARGs的能力，我们开发了一种紫外线辅助电化学氧化（UV-EO）工艺，该工艺采用蓝色TiO纳米管阵列（BNTA）作为光阳极。分别通过在选择性琼脂上平板计数和定量PCR来测定四环素和磺胺甲恶唑抗性的灭活以及相应质粒编码基因（和）的降解。与单独紫外线照射相比，UV-EO可增强ARB灭活和ARG降解。由于电化学产生游离氯以及随后的紫外线/氯光反应，氯化物显著提高了灭活效率。对于长和短目标基因，UV-EO在Cl中的基于通量的一级动力学速率系数分别比单独紫外线照射大2.1-2.3倍和1.3-1.8倍。使用凝胶电泳和计算动力学模型进一步探索了不同自由基对质粒DNA的损伤机制。该工艺可有效消除厕所废水中的ARB和ARGs，尽管动力学有所延迟。
