College of Environmental Science and Engineering, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250353, China.
Advanced Materials Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan, 250014, China.
Environ Pollut. 2022 May 15;301:119031. doi: 10.1016/j.envpol.2022.119031. Epub 2022 Feb 19.
Antibiotics accumulation in the environment has given rise to multi-drug resistant 'superbugs' and antibiotics resistence genes (ARGs). Chloramphenicol (CAP), a kind of widely used antibiotics, was chosen as the model compound to investigate its degradation during electrochemical treatment process. The prepared Ti/PbO-La electrodes had a denser surface and a more complete PbO crystal structure than Ti/PbO electrode. The doping of La increased the onset potential and the overpotential, increased the current value of the oxidation peak and the reduction peak, reduced the impedance, and increased the lifetime. The reactions CAP degradation and TOC removal on Ti/PbO-La electrode was both primary kinetic reactions. CAP degradation rate increased with current density, and TOC obtained the highest removal at current density of 25 mA cm. The electrolyte concentration had a small effect in the range of 0.050-0.150 mol L. The effects under acidic and neutral conditions were better than under alkaline conditions. CAP was mainly directly oxidized at the electrode surface and indirect oxidation also took place via generated ·OH and SO. 15 intermediates and 2 degradation pathways have been postulated. The entry of CAP and CAP intermediates into the environment caused the alteration in bacterial community and ARGs, while complete degradation products had little effect on them. Redundancy analysis showed that intI1 was the dominant factor affecting ARGs, and Actinobacteria and Patescibacteria were the main factors affecting the abundances of ARGs in the microbial community.
抗生素在环境中的积累导致了多药耐药的“超级细菌”和抗生素耐药基因（ARGs）的出现。氯霉素（CAP）是一种广泛使用的抗生素，被选为模型化合物，以研究其在电化学处理过程中的降解情况。制备的 Ti/PbO-La 电极具有比 Ti/PbO 电极更致密的表面和更完整的 PbO 晶体结构。La 的掺杂增加了起始电位和过电位，增加了氧化峰和还原峰的电流值，降低了阻抗，并延长了寿命。Ti/PbO-La 电极上 CAP 降解和 TOC 去除的反应均为一级动力学反应。CAP 的降解速率随电流密度的增加而增加，在电流密度为 25 mA cm 时 TOC 去除率最高。电解质浓度在 0.050-0.150 mol L 范围内影响较小。在酸性和中性条件下的效果优于碱性条件。CAP 主要在电极表面直接氧化，也通过生成的·OH 和 SO 进行间接氧化。推测出 15 种中间体和 2 种降解途径。CAP 和 CAP 中间体进入环境会导致细菌群落和 ARGs 的改变，而完全的降解产物对它们的影响很小。冗余分析表明，intI1 是影响 ARGs 的主要因素，而放线菌和 Patescibacteria 是影响微生物群落中 ARGs 丰度的主要因素。
