Simultaneous removal of chromate and arsenite by the immobilized Enterobacter bacterium in combination with chemical reagents
Simultaneous removal of chromate and arsenite by the immobilized Enterobacter bacterium in combination with chemical reagents
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固定化肠杆菌结合化学试剂同时去除铬酸盐和亚砷酸盐
DOI：
10.1016/j.chemosphere.2020.127428
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发表时间：
2020-11-01
期刊：
影响因子：
8.8
通讯作者：
Wang, Gejiao
中科院分区：
文献类型：
--
作者：
Shi, Kaixiang;Dai, Xingli;Wang, Gejiao
同时铬酸盐[Cr（VI）]还原和亚砷酸盐[As（III）]氧化是一种很有前途的去除Cr和As的预处理工艺。在此，兼性厌氧细菌肠杆菌属（Enterobacter sp.）Z（1）在温度（20-45摄氏度）和pH的野生范围内的缺氧培养期间呈现同时Cr（VI）还原和As（III）氧化的能力（Cerkez等人，2015年; Chen等人，2015;中国环境保护，1996; Fan等人，2008年，2019年）。引人注目的是，菌株Z1可以同时贡献高达92.8%的Cr（VI）的还原和45.8%的As（III）的氧化在废水中。菌株Z1的细胞与海藻酸钠包埋生产的生物珠，并表现出稳定的Cr（VI）的还原率（91.8%）和As（III）的氧化率（29.6%），即使在5个连续循环的废水处理。经Z1菌球预处理后，再经Ca（OH）2和FeCl 3沉淀，废水中总铬和砷的去除率分别为98.9%和98.3%，比单独使用Ca（OH）2和FeCl 3的去除率分别提高了44.1%和9.8%。Cr、As残留量均达到国家污水排放标准。蛋白质组学分析表明，Cr（VI）和As（III）诱导了半胱氨酸、硫和蛋氨酸的代谢、抗砷性和氧化还原酶（CysH、CysI、CysJ、NemA和HemF）的产生。此外，添加半胱氨酸的培养基也显着提高细菌Cr（VI）的还原率。本研究为强化废水中Cr（VI）和As（III）污染的微生物预处理提供了一种新的途径，并揭示了半胱氨酸、硫和蛋氨酸代谢、抗As能力和氧化还原酶与Cr（VI）和As（III）的氧化还原转化之间的关系。(C)2020爱思唯尔有限公司保留所有权利。
Simultaneous chromate [Cr(VI)] reduction and arsenite [As(III)] oxidation is a promising pretreatment process for Cr and As removal. Here, a facultative anaerobic bacterium, Enterobacter sp. Z(1), presented capacities of simultaneous Cr(VI) reduction and As(III) oxidation during anoxic cultivation in a wild range of temperature (20-45 degrees C) and pH (Cerkez et al., 2015; Chen et al., 2015; China Environmental Prote, 1996; Fan et al., 2008, 2019) conditions. Strikingly, strain Z1 could simultaneously contribute up to 92.8% of the reduction of Cr(VI) and 45.8% of the oxidation of As(III) in wastewater. The cells of strain Z1 were embedded with sodium alginate to produce biobeads, and the biobeads exhibited stable ratio of Cr(VI) reduction (91.8%) and As(III) oxidation (29.6%) even in the 5 continuous cycles of wastewater treatment. Moreover, in a process pretreated with the Z1 biobeads followed a precipitation with Ca(OH)(2) and FeCl3, the removal efficiencies in wastewater were 98.9% and 98.3% for total Cr and As, respectively, which were 44.1% and 9.8% higher than those of using Ca(OH)(2) and FeCl3, only. The residual amounts of Cr and As met the national standard levels of wastewater discharge. Proteomics analysis showed that cysteine, sulfur and methionine metabolisms, As resistance and oxidoreductase (CysH, CysI, CysJ, NemA and HemF) were induced by Cr(VI) and As(III). Moreover, the addition of cysteine to the medium also significantly improved bacterial Cr(VI) reduction rate. Our results provide a novel microbial pretreatment approach for enhancing remediation of Cr(VI) and As(III) pollution in wastewater, and reveal the evident that cysteine, sulfur and methionine metabolisms, As resistance and oxidoreductases are associated with the redox conversion of Cr(VI) and As(III). (C) 2020 Elsevier Ltd. All rights reserved.