Laboratory of Water Pollution Remediation, School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China.
Teaching Center, Zhejiang Open University, Hangzhou 310012, China.
Sci Total Environ. 2022 Feb 10;807(Pt 1):150784. doi: 10.1016/j.scitotenv.2021.150784. Epub 2021 Oct 5.
The effects of multiple antibiotics on the anaerobic ammonia oxidation (anammox) process were investigated. The resistance of the anammox system to high-concentration antibiotics was also demonstrated through gradual acclimation experiments. Inhibition of the anammox process (R) occurred when the concentrations of erythromycin (ERY), sulfamethoxazole (SMX) and tetracycline (TC) were 0.1, 5.0 and 0.1 mg L, respectively. The nitrogen removal efficiency (NRE) of R was reduced from 97.2% to 60.7% within 12 days and then recovered to 88.9 ± 9.5% when the nitrogen loading declined from 4.52 ± 0.69 to 2.11 ± 0.58 kg N m d. Even when the concentrations of ERY, SMX and TC were as high as 1.0, 15.0 and 1.0 mg L, respectively, R maintained stable operation. The increases in the abundance of antibiotic resistance genes (ARGs) and in extracellular polymeric substances (EPS) content showed that the anammox process alleviated stress from multiple antibiotics mainly by producing ARGs and secreting EPS. The molecular docking simulation results illustrated the potential binding sites between ammonium transporter and different antibiotics. The upregulation of functional gene expression and the stable abundance of Candidatus Kuenenia in R compared with that in the control suggested that the R reactor generally maintained more stable long-term operation. This work provides a new understanding of the application of the anammox process to treat wastewater containing multiple antibiotics.
研究了多种抗生素对厌氧氨氧化（anammox）过程的影响。通过逐步驯化实验，还证明了 anammox 系统对高浓度抗生素的抗性。当红霉素（ERY）、磺胺甲恶唑（SMX）和四环素（TC）的浓度分别为 0.1、5.0 和 0.1 mg/L 时，anammox 过程受到抑制（R）。在 12 天内，R 的氮去除效率（NRE）从 97.2%降低到 60.7%，当氮负荷从 4.52±0.69 kg N m d 降低到 2.11±0.58 kg N m d 时，恢复到 88.9±9.5%。即使 ERY、SMX 和 TC 的浓度分别高达 1.0、15.0 和 1.0 mg/L，R 仍能稳定运行。抗生素抗性基因（ARGs）和胞外聚合物物质（EPS）含量的增加表明，anammox 过程主要通过产生 ARGs 和分泌 EPS 来缓解多种抗生素的压力。分子对接模拟结果说明了氨转运蛋白与不同抗生素之间的潜在结合位点。与对照相比，R 中功能基因表达的上调和 Candidatus Kuenenia 的稳定丰度表明，R 反应器通常能保持更稳定的长期运行。这项工作为 anammox 工艺应用于处理含有多种抗生素的废水提供了新的认识。
