Guangdong Provincial Research Center for Environment Pollution Control and Remediation Materials, College of Life Science and Technology, Jinan University, Guangzhou 510632, China.
School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
J Hazard Mater. 2023 Aug 15;456:131668. doi: 10.1016/j.jhazmat.2023.131668. Epub 2023 May 19.
Aniline aerofloat (AAF) is a refractory organic pollutant in floatation wastewater. Little information is currently available on its biodegradation. In this study, a novel AAF-degrading strain named Burkholderia sp. WX-6 was isolated from mining sludge. The strain could degrade more than 80% of AAF at different initial concentrations (100-1000 mg/L) within 72 h. AAF degrading curves were fitted well with the four-parameter logistic model (R >0.97), with the degrading half-life ranging from 16.39 to 35.55 h. This strain harbors metabolic pathway for complete degradation of AAF and is resistant to salt, alkali, and heavy metals. Immobilization of the strain on biochar enhanced both tolerance to extreme conditions and AAF removal, with up to 88% of AAF removal rate in simulated wastewater under alkaline (pH 9.5) or heavy metal pollution condition. In addition, the biochar-immobilized bacteria removed 59.4% of COD in the wastewater containing AAF and mixed metal ions within 144 h, significantly (P < 0.05) higher than those by free bacteria (42.6%) and biochar (48.2%) only. This work is helpful to understand AAF biodegradation mechanism and provides viable references for developing practical biotreatment technique of mining wastewater.
偶氮甲酰胺（AAF）是浮选废水中的一种难生物降解的有机污染物。目前关于其生物降解的信息较少。本研究从矿山污泥中分离到一株能够降解 AAF 的新菌株，命名为 Burkholderia sp. WX-6。该菌株在 72 h 内能够在不同初始浓度（100-1000 mg/L）下降解超过 80%的 AAF。AAF 的降解曲线与四参数逻辑模型拟合良好（R >0.97），降解半衰期为 16.39-35.55 h。该菌株具有完整降解 AAF 的代谢途径，并且能够耐受盐、碱和重金属。将该菌株固定在生物炭上，提高了其对极端条件和 AAF 去除的耐受性，在碱性（pH 9.5）或重金属污染条件下的模拟废水中，AAF 的去除率高达 88%。此外，在含有 AAF 和混合金属离子的废水中，生物炭固定化细菌在 144 h 内去除了 59.4%的 COD，明显高于游离细菌（42.6%）和生物炭（48.2%）。这项工作有助于理解 AAF 的生物降解机制，并为开发矿山废水的实用生物处理技术提供了可行的参考。
