School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China.
School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, PR China.
J Hazard Mater. 2021 Jul 15;414:125051. doi: 10.1016/j.jhazmat.2021.125051. Epub 2021 Jan 6.
The aim of present study was to re-evaluate the impacts of elevated Fe(III) stress on anaerobic ammonium oxidation (anammox) process. The results indicated that long-term low concentration Fe(III) (5 and 10 mg/L) exposure significantly improved the nitrogen removal efficiency of anammox process, while high concentration Fe(III) (50 and 100 mg/L) significantly deteriorated the reactor performance. Batch assays showed that the specific anammox activity, heme c content and hydrazine dehydrogenase activity were significantly increased and decreased under low and high concentration Fe(III) exposure, respectively, indicating an enhancement and inhibition of anammox activity. Moreover, the presence of high concentration Fe(III) significantly shifted the anammox community structure. Ca. Brocadia was the predominant anammox genus, whose abundance decreased from 14.26% to 8.13% as Fe(III) concentration increased from 0 to 100 mg/L. In comparison, the abundance of denitrifiers progressively increased from 3.70% to 6.68% with increasing Fe(III) concentration. These suggested that different functional bacteria differed in their responses to Fe(III) stress. Furthermore, long-term Fe(III) exposure significantly up-regulated the abundances of genes associated with nitrogen metabolism and Fe(III) reduction. Overall, the obtained findings are expected to advances our understanding of the responses of anammox process to elevated Fe(III) stress.
本研究旨在重新评估高铁胁迫对厌氧氨氧化（anammox）过程的影响。结果表明，长期低浓度 Fe(III)（5 和 10mg/L）暴露显著提高了 anammox 过程的脱氮效率，而高浓度 Fe(III)（50 和 100mg/L）则显著恶化了反应器性能。批实验表明，在低浓度和高浓度 Fe(III)暴露下，anammox 活性、血红素 c 含量和肼脱氢酶活性分别显著增加和降低，表明 anammox 活性受到促进和抑制。此外，高浓度 Fe(III)的存在显著改变了 anammox 群落结构。Ca. Brocadia 是优势 anammox 属，其丰度从 0mg/L 时的 14.26%下降到 100mg/L 时的 8.13%。相比之下，反硝化菌的丰度随着 Fe(III)浓度的增加从 3.70%逐渐增加到 6.68%。这表明不同功能细菌对 Fe(III)胁迫的反应不同。此外，长期 Fe(III)暴露显著上调了与氮代谢和 Fe(III)还原相关的基因的丰度。总的来说，这些发现有望增进我们对 anammox 过程对高铁胁迫的响应的理解。
