Wang Zhao, Su Junfeng, Ali Amjad, Zhang Ruijie, Yang Wenshuo, Xu Liang, Zhao Tingbao
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
J Hazard Mater. 2021 Aug 15;416:125914. doi: 10.1016/j.jhazmat.2021.125914. Epub 2021 Apr 17.
A simultaneous denitrifying and mineralizing bacterium, Pseudomonas sp. WZ39 was isolated for fluoride (F), nitrate (NO-N), and calcium (Ca) removal. Strain WZ39 exhibited a remarkable defluoridation efficiency of 87.49% under a pH of 6.90, F and Ca concentration of 1.99 and 201.88 mg L, respectively. EEM, SEM-EDS, XRD, and FTIR analyses elucidated the chemical adsorption and co-precipitation with calcium salt contributed to the removal of F. The mechanisms of biomineralization were also investigated by determining the role of bound and unbound extracellular polymeric substances (EPS), cell wall, and calcium channel in nucleation. The results showed that bacteria can promote nucleation on the templates of cell walls or EPS through the electrostatic effect. The presence of the calcium channel blocker inhibited the transport of intracellular Ca to the extracellular environment. The outcome of the present research can provide a theoretical basis for the understanding of MICP phenomenon and the efficient treatment of F containing groundwater.
分离出一种同时具有反硝化和矿化作用的细菌——假单胞菌属WZ39，用于去除氟化物（F）、硝酸盐（NO-N）和钙（Ca）。在pH值为6.90、F浓度为1.99 mg/L和Ca浓度为201.88 mg/L的条件下，菌株WZ39表现出87.49%的显著除氟效率。三维荧光光谱（EEM）、扫描电子显微镜-能谱仪（SEM-EDS）、X射线衍射（XRD）和傅里叶变换红外光谱（FTIR）分析表明，化学吸附和与钙盐的共沉淀有助于F的去除。通过确定结合态和非结合态胞外聚合物（EPS）、细胞壁和钙通道在成核中的作用，还研究了生物矿化机制。结果表明，细菌可以通过静电作用促进在细胞壁或EPS模板上的成核。钙通道阻滞剂的存在抑制了细胞内Ca向细胞外环境的转运。本研究结果可为理解微生物诱导碳酸钙沉淀（MICP）现象和含氟地下水的有效处理提供理论依据。
