Enrofloxacin Transformation on Shewanella oneidensis MR-1 Reduced Goethite during Anaerobic-Aerobic Transition
Enrofloxacin Transformation on Shewanella oneidensis MR-1 Reduced Goethite during Anaerobic-Aerobic Transition
复制标题
恩诺沙星对希瓦氏菌 MR-1 的转化在厌氧-需氧转变过程中还原了针铁矿
DOI：
10.1021/acs.est.6b03054
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发表时间：
2016
影响因子：
11.4
通讯作者：
Jing CY
中科院分区：
文献类型：
--
作者：
Yan Wei;Jing Chuanyong;Zhang Jianfeng;Jing CY
抗生素污染具有很高的生态风险，已成为世界性的环境问题。在本研究中，观察到恩诺沙星(ENR)在针铁矿上由厌氧向好氧过渡的过程中，在单核希瓦氏菌MR-1存在下的快速降解。非生物反应还表明，初始浓度为10 mg的L-1ENR在5min内可被吸附了Fe(II)的针铁矿好氧去除70%以上，且不需要特殊的照射和强氧化剂。自旋俘获电子自旋共振(ESR)实验结果表明，Fe(II)/Fe(III)络合物促进了·OH的生成。·OH的亲电攻击打开了ENR的喹诺酮环，引发了进一步的转化反应。用高效液相色谱-四极杆飞行时间质谱仪鉴定了5种转化产物，并据此提出了ENR的降解过程。对ENR转化产物的鉴定还表明，表面吸附和分子内电子密度分布共同决定了反应位置和转化途径。这项研究强调了抗生素原位降解的一个重要但往往被低估的自然过程。由于针铁矿-MR-1复合体很容易迁移到厌氧/好氧界面，ENR和其他抗生素的环境命运需要认真重新考虑。
Antibiotics pollution has become a critical environmental issue worldwide due to its high ecological risk. In this study, rapid degradation of enrofloxacin (ENR) was observed on goethite in the presence ofShewanella oneidensisMR-1 during the transition from anaerobic to aerobic conditions. The abiotic reactions also demonstrated that over 70% with initial concentration of 10 mg L–1ENR was aerobically removed within 5 min by goethite with adsorbed Fe(II), without especial irradiation and strong oxidants. The results of spin trap electron spin resonance (ESR) experiments provide evidence that Fe(II)/Fe(III) complexes facilitate the generation of •OH. The electrophilic attack by •OH opens the quinolone ring of ENR and initiates further transformation reactions. Five transformation products were identified using high performance liquid chromatography-quadrupole time-of-flight mass spectrometry and the ENR degradation process was proposed accordingly. The identification of ENR transformation products also revealed that both the surface adsorption and the electron density distribution in the molecule determined the reactive site and transformation pathway. This study highlights an important, but often underappreciated, natural process for in situ degradation of antibiotics. With the easy migration of the goethite-MR-1 complex to the anaerobic/aerobic interface, the environmental fates of ENR and other antibiotics need to be seriously reconsidered.