Jiangsu Key Laboratory of Chemical Pollution Control and Resources Reuse, School of Environmental and Biological Engineering, Nanjing University of Science and Technology, Nanjing 210094, China.
CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China.
Water Res. 2020 Nov 1;186:116306. doi: 10.1016/j.watres.2020.116306. Epub 2020 Aug 16.
Due to highly recalcitrant and toxicological nature of N,N-dimethylformamide (DMF), efficient removal of DMF is challenging for biological wastewater treatment. In this study, an anoxic denitrification system was developed and continuously operated for 220 days in order to verify the enhanced DMF biodegradation mechanism. As high as 41.05 mM DMF could be thoroughly removed in the anoxic denitrification reactor at hydraulic residence time (HRT) of 24 h, while the total organic carbon (TOC) and nitrate removal efficiencies were as high as 95.7 ± 2.5% and 98.4 ± 1.1%, respectively. Microbial community analyses indicated that the species related to DMF hydrolysis (Paracoccus, Brevundimonas and Chryseobacterium) and denitrification (Paracoccus, Arenimonas, Hyphomicrobium, Aquamicrobium and Bosea) were effectively enriched in the anoxic denitrification system. Transcriptional analysis coupled with enzymatic activity assay indicated that both hydrolysis and mineralization of DMF were largely enhanced in the anoxic denitrification system. Moreover, the occurrence of microbial denitrification distinctly facilitated carbon source utilization to produce electron and energy, which was rather beneficial for better reactor performance. This study demonstrated that the anoxic denitrification system would be a potential alternative for efficient treatment of wastewater polluted by recalcitrant pollutants such as DMF.
由于 N,N-二甲基甲酰胺（DMF）具有很强的抗降解性和毒性，因此高效去除 DMF 对生物废水处理来说是一个挑战。在本研究中，开发了一种缺氧反硝化系统，并连续运行了 220 天，以验证增强的 DMF 生物降解机制。在水力停留时间（HRT）为 24 小时的缺氧反硝化反应器中，高达 41.05 mM 的 DMF 可以被彻底去除，而总有机碳（TOC）和硝酸盐去除效率分别高达 95.7±2.5%和 98.4±1.1%。微生物群落分析表明，与 DMF 水解（Paracoccus、Brevundimonas 和 Chryseobacterium）和反硝化（Paracoccus、Arenimonas、Hyphomicrobium、Aquamicrobium 和 Bosea）相关的物种在缺氧反硝化系统中得到了有效富集。转录分析结合酶活性测定表明，DMF 的水解和矿化在缺氧反硝化系统中得到了很大的增强。此外，微生物反硝化的发生明显促进了碳源的利用，从而产生电子和能量，这对更好的反应器性能非常有利。本研究表明，缺氧反硝化系统将是处理含有难降解污染物（如 DMF）废水的一种潜在替代方法。
