Donghua University, College of Environmental Science and Engineering, Shanghai, 201600, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China.
Donghua University, College of Environmental Science and Engineering, Shanghai, 201600, China.
J Environ Manage. 2023 Nov 1;345:118897. doi: 10.1016/j.jenvman.2023.118897. Epub 2023 Sep 6.
Nitrate and SMX both play a critical role in their biotransformation in biodegradable polymer-supported denitrification biofilters. However, the mutual influences of nitrate and SMX on their biotransformation for long-term operation remained obscure. Results showed SMX and nitrate had divergent effects on SMX removal. SMX removal rates was positively related with its loading rates, whereas they were negatively related to NLRs. The most abundant metabolite CHONS (the reduced form of SMX moiety) from the N-O bond cleavage pathway by UHPLC-LTQ-Orbitrap-MS/MS and effluent TOC variations confirmed the presence of electron donor competition between nitrate and SMX. SMX less than 1000 μg/L had a negligible influence on denitrification performance. Denitrifiers such as Azospira and Denitratisoma were still enriched after chronic exposure, and nosZ/narG positively correlated with sul1/sul2 resistance genes, which were both responsible for the negligible influence of SMX. This work could guide the operational management of denitrification biofilters for simultaneous nitrate and antibiotics removal.
硝酸盐和磺胺甲恶唑在可生物降解聚合物支持的反硝化生物滤池中生物转化中都起着关键作用。然而，硝酸盐和磺胺甲恶唑对其长期运行中的生物转化的相互影响尚不清楚。结果表明，磺胺甲恶唑和硝酸盐对磺胺甲恶唑去除有不同的影响。磺胺甲恶唑去除率与磺胺甲恶唑的负载率呈正相关，而与 NLRs 呈负相关。通过 UHPLC-LTQ-Orbitrap-MS/MS 和出水 TOC 变化，从 N-O 键断裂途径得到的最丰富的代谢物 CHONS（SMX 部分的还原形式）证实了硝酸盐和磺胺甲恶唑之间存在电子供体竞争。浓度低于 1000μg/L 的磺胺甲恶唑对反硝化性能的影响可以忽略不计。在慢性暴露后，仍然富集了反硝化菌，如 Azospira 和 Denitratisoma，并且 nosZ/narG 与 sul1/sul2 抗性基因呈正相关，这两个基因都负责磺胺甲恶唑的影响可以忽略不计。这项工作可以指导同时去除硝酸盐和抗生素的反硝化生物滤池的运行管理。
