School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-sen University), Guangzhou 510275, China.
School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology (Sun Yat-sen University), Guangzhou 510275, China.
Sci Total Environ. 2019 Jun 10;668:379-388. doi: 10.1016/j.scitotenv.2019.02.389. Epub 2019 Feb 26.
Anammox-related processes are often applied for the wastewater treatment which contains both ammonium and antibiotics. Herein, the long-term effects of tetracycline (TC), at environmentally and industrially relevant concentrations, on the performance, anammox activity and microbial community of anammox reactors were investigated for 518 days. The control reactor (without TC exposure) was stable for nitrogen removal during the long-term operation (a nitrogen removal rate of 0.56 ± 0.05 kg-N·m·d). In the TC-added reactor, the nitrogen removal efficiency increased slightly at low TC levels (1-100 μg/L), whereas poor anammox performance occurred at high TC concentration (1000 μg/L). Furthermore, the concentrations of extracellular polymeric substances (EPS) were much higher at 10 μg/L than those in the control reactor (P < 0.01), whereas rapidly decreased at 1000 μg-TC/L. Furthermore, the reactor performance was highly consistent with the variations of the heme c contents. Consistently, exposure to TC changed the abundance of anammox bacteria, e.g., an increase in Candidatus Jettenia abundance occurred from 2.20 ± 0.97% (0-10 μg/L) to 12.13 ± 1.66% (100 μg/L). Similarly, the genus Denitratisoma, the most predominant denitrification bacteria, also had a higher abundance at a TC concentration of 100 μg/L (15.60 ± 6.42%) than other TC concentrations (5.40 ± 2.50% and 7.65 ± 0.55% at concentrations of 10 and 1000 μg/L, respectively). The results can explain why the exposure of anammox bacteria to a lower TC concentration (100 μg/L) resulted in a better nitrogen removal rate. In contrast, exposure to a high TC level (1000 μg/L) led to a decline in the abundance of anammox bacteria and denitrifiers (1.53 ± 0.64% and 8.18 ± 0.63%, respectively) but an increased abundance in the nitrifier population (8.07 ± 1.21%; P < 0.01). Therefore, this study can aid in the design and operation of anammox-based processes treating sewage and industrial wastewater.
厌氧氨氧化相关工艺常用于同时含有氨氮和抗生素的废水处理。在此，研究了在环境和工业相关浓度下，四环素（TC）对厌氧氨氧化反应器性能、厌氧氨氧化活性和微生物群落的长期影响，实验持续了 518 天。在长期运行过程中，没有 TC 暴露的对照反应器（无 TC 暴露）的氮去除率稳定（氮去除速率为 0.56 ± 0.05 kg-N·m·d）。在 TC 添加的反应器中，在低 TC 水平（1-100μg/L）下，氮去除效率略有提高，而在高 TC 浓度（1000μg/L）下，厌氧氨氧化性能较差。此外，在 10μg/L 时，胞外聚合物（EPS）的浓度明显高于对照反应器（P<0.01），而在 1000μg-TC/L 时迅速下降。此外，反应器性能与血红素 c 含量的变化高度一致。一致地，TC 的暴露改变了厌氧氨氧化细菌的丰度，例如，Candidatus Jettenia 的丰度从 2.20 ± 0.97%（0-10μg/L）增加到 12.13 ± 1.66%（100μg/L）。同样，优势脱氮菌属 Denitratisoma 在 TC 浓度为 100μg/L 时的丰度也更高（15.60 ± 6.42%），而在其他 TC 浓度时（分别为 10μg/L 和 1000μg/L 时为 5.40 ± 2.50%和 7.65 ± 0.55%）。结果可以解释为什么厌氧氨氧化细菌暴露于较低的 TC 浓度（100μg/L）会导致更好的氮去除率。相反，暴露于高 TC 水平（1000μg/L）会导致厌氧氨氧化细菌和脱氮菌的丰度下降（分别为 1.53 ± 0.64%和 8.18 ± 0.63%），但硝化菌的丰度增加（8.07 ± 1.21%；P<0.01）。因此，这项研究有助于设计和运行处理污水和工业废水的基于厌氧氨氧化的工艺。
