UAM-Iztapalapa, Departamento de Biotecnología, Av. San Rafael Atlixco 186, Col. Vicentina, C.P., 09340, Ciudad de México, Mexico.
UPAEP, Departamento de Ciencias Biológicas, 11 Poniente 2316, Col. Barrio de Santiago, C.P., 72410, Puebla, Mexico.
Chemosphere. 2021 May;270:129461. doi: 10.1016/j.chemosphere.2020.129461. Epub 2020 Dec 28.
Benzotriazole (BT) is a corrosion inhibitor widely distributed in aquatic environments. Little is known about the cometabolic capacity of stabilized nitrifying sludge to biotransform BT. The contribution of the nitrification process in the simultaneous oxidation of ammonium and biotransformation of BT (5 mg/L) was evaluated in 49 d batch cultures inoculated with a sludge produced in steady-state nitrification. The nitrifying sludge could consume BT in the obligate presence of ammonium. A higher cometabolic biotransformation capacity was obtained by increasing the initial ammonium concentration (100-300 mg N/L), reaching 2.3- and 5.8-fold increases for efficiency and specific rate of BT removal. At 300 mg NH-N/L, the sludge biotransform 40.8% of BT and 77.6% of ammonium which was completely oxidized into nitrate. In assays with allylthiourea added as specific inhibitor of ammonium monooxygenase (AMO), it was shown that the totality of BT cometabolic biotransformation was associated with the AMO activity. The addition of acetate did not favor heterotrophic biotransformation of BT. BT provoked inhibitory effects on nitrification. This is the first study showing the role of ammonium oxidizing bacteria in the cometabolic biotransformation of BT and their potential use for cometabolism application in treatment of wastewater contaminated with ammonium and BT.
苯并三唑（BT）是一种广泛分布于水生环境中的腐蚀抑制剂。关于稳定硝化污泥对 BT 进行共代谢转化的能力知之甚少。本研究在稳态硝化条件下接种硝化污泥进行 49 d 的批式培养，评估了硝化过程对同时氧化氨和 BT（5 mg/L）进行生物转化的贡献。硝化污泥可以在强制存在氨的情况下消耗 BT。通过增加初始氨浓度（100-300 mg N/L），可以获得更高的共代谢生物转化能力，BT 的去除效率和比去除速率分别提高了 2.3 倍和 5.8 倍。在 300 mg NH-N/L 时，污泥共代谢转化了 40.8%的 BT 和 77.6%的氨，氨被完全氧化成硝酸盐。在添加丙烯基硫脲作为氨单加氧酶（AMO）特异性抑制剂的实验中，表明 BT 的共代谢生物转化总量与 AMO 活性有关。添加乙酸盐不利于 BT 的异养生物转化。BT 对硝化有抑制作用。这是首次研究表明氨氧化菌在 BT 的共代谢生物转化中的作用及其在处理同时含有氨和 BT 的废水方面的共代谢应用潜力。
