School of Civil Engineering, Wuhan University, Wuhan 430072, China.
State Key Lab of Urban Water Resources and Environment, Harbin Institute of Technology, Harbin 150090, China.
Bioresour Technol. 2016 Oct;218:189-95. doi: 10.1016/j.biortech.2016.06.081. Epub 2016 Jun 21.
Bioelectrochemical denitrification system (BEDS) is a promising technology for nitrate removal from wastewaters. The hazards and effects concerning p-nitrophenol (PNP) towards BEDS lack enough investigations and possess great research prospects. This study investigated how PNP affected the nitrate removal efficiency, microbial communities, functional denitrifying genes abundances, nitrate and nitrite reductase activities, diffusible signal factors (DSF) release, and extracellular polymeric substances (EPS) production in the BEDS. Results indicated that nitrate removal efficiency decreased with initial PNP concentration increased from 0 to 100mg/L. Phylum Firmicutes and class Clostridia were the main contributors for denitrification process in this BEDS. The abundances of the denitrifying genes nirS, nirK, napA, and narG all presented decreased trends with increasing PNP. In addition, the concentrations of nitrate reductase (NR), nitrite reductase (NIR), and EPS obviously decreased, while the concentration of DSF increased with increasing PNP, which demonstrated that higher PNP would inhibit the biofilm formation.
生物电化学反硝化系统（BEDS）是一种很有前途的从废水中去除硝酸盐的技术。然而，有关对硝基苯酚（PNP）对 BEDS 的危害和影响的研究还不够充分，具有很大的研究前景。本研究探讨了 PNP 如何影响 BEDS 中的硝酸盐去除效率、微生物群落、功能反硝化基因丰度、硝酸盐和亚硝酸盐还原酶活性、可扩散信号因子（DSF）释放和细胞外聚合物（EPS）产生。结果表明，随着初始 PNP 浓度从 0 增加到 100mg/L，硝酸盐去除效率降低。在该 BEDS 中，厚壁菌门和梭菌纲是反硝化过程的主要贡献者。反硝化基因 nirS、nirK、napA 和 narG 的丰度均随 PNP 的增加而呈下降趋势。此外，随着 PNP 的增加，硝酸盐还原酶（NR）、亚硝酸盐还原酶（NIR）和 EPS 的浓度明显降低，而 DSF 的浓度增加，这表明较高的 PNP 会抑制生物膜的形成。
