Department of Chemical Engineering, School of Engineering, Universidade de Santiago de Compostela, Rúa Lope Gómez de Marzoa, Santiago de Compostela, E-15782, Spain.
Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, Koblenz, D-56068, Germany.
Water Res. 2019 Apr 1;152:202-214. doi: 10.1016/j.watres.2018.12.064. Epub 2019 Jan 11.
Biotransformation of organic micropollutants (OMPs) in wastewater treatment plants ultimately depends on the enzymatic activities developed in each biological process. However, few research efforts have been made to clarify and identify the role of enzymes on the removal of OMPs, which is an essential knowledge to determine the biotransformation potential of treatment technologies. Therefore, the purpose of the present study was to investigate the enzymatic transformation of 35 OMPs under anaerobic conditions, which have been even less studied than aerobic systems. Initially, 13 OMPs were identified to be significantly biotransformed (>20%) by anaerobic sludge obtained from a full-scale anaerobic digester, predestining them as potential targets of anaerobic enzymes. Native enzymes were extracted from this anaerobic sludge to perform transformation assays with the OMPs. In addition, the effect of detergents to recover membrane enzymes, as well as the effects of cofactors and inhibitors to promote and suppress specific enzymatic activities were evaluated. In total, it was possible to recover enzymatic activities towards 10 out of these 13 target OMPs (acetyl-sulfamethoxazole and its transformation product sulfamethoxazole, acetaminophen, atenolol, clarithromycin, citalopram, climbazole, erythromycin, and terbutryn, venlafaxine) as well as towards 8 non-target OMPs (diclofenac, iopamidol, acyclovir, acesulfame, and 4 different hydroxylated metabolites of carbamazepine). Some enzymatic activities likely involved in the anaerobic biotransformation of these OMPs were identified. Thereby, this study is a starting point to unravel the still enigmatic biotransformation of OMPs in wastewater treatment systems.
废水处理厂中有机微污染物（OMPs）的生物转化最终取决于每个生物过程中发展的酶活性。然而，很少有研究致力于阐明和识别酶在去除 OMPs 方面的作用，这是确定处理技术生物转化潜力的必要知识。因此，本研究的目的是在厌氧条件下研究 35 种 OMPs 的酶转化，这比好氧系统研究得更少。最初，从一个规模的厌氧消化器中鉴定出 13 种 OMPs 被厌氧污泥显著转化（>20%），这使它们成为厌氧酶的潜在目标。从这种厌氧污泥中提取天然酶来进行 OMPs 的转化测定。此外，还评估了洗涤剂回收膜酶的效果，以及辅助因子和抑制剂对促进和抑制特定酶活性的影响。总共，有可能恢复 13 种目标 OMP 中的 10 种（乙酰磺胺甲恶唑及其转化产物磺胺甲恶唑、对乙酰氨基酚、阿替洛尔、克拉霉素、西酞普兰、克霉唑、红霉素和特布他林）以及 8 种非目标 OMP（双氯芬酸、碘帕醇、阿昔洛韦、醋磺胺甲恶唑和卡马西平的 4 种不同羟基代谢物）的酶活性。确定了一些可能参与这些 OMP 厌氧生物转化的酶活性。因此，这项研究是揭示废水处理系统中 OMP 生物转化仍然神秘的起点。
