| 引用本文: | 曹驰程,王友权,章奇,张晖.典型湖泊天然有机质与四环素的相互作用.湖泊科学,2018,30(4):1004-1011. DOI:10.18307/2018.0413 |
| CAO Chicheng,WANG Youquan,ZHANG Qi,ZHANG Hui.Interactions of tetracycline and dissolved organic matter from freshwater lakes. J. Lake Sci.2018,30(4):1004-1011. DOI:10.18307/2018.0413 |
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| 摘要: |
| 采用荧光滴定法研究四环素（tetracycline，TC）与太湖溶解性有机质（dissolved organic matter，DOM）和玄武湖DOM的相互作用.三维荧光光谱结合平行因子分析显示，2个湖泊的DOM含有3个荧光组分：类富里酸组分C1、类色氨酸组分C2和类络氨酸组分C3.其中C2的荧光强度远高于C1和C3，是DOM的主要荧光组成.3个荧光组分与TC发生了不同程度的静态猝灭，特别当TC浓度为45.5 μmol/L时，类蛋白组分的荧光强度完全被猝灭（100%），并且猝灭作用改变了DOM分子的微环境极性.同步荧光光谱联合二维相关图谱进一步表明类色氨酸组分优先和TC发生猝灭作用，其次为类络氨酸组分和类富里酸组分.Ryan-Weber方程适于拟合DOM与TC的猝灭过程，2个湖泊的DOM中3个荧光组分的络合常数lgK值范围为5.05~5.85，大小顺序为C2 > C3 > C1.因此，类蛋白组分为主的DOM对TC的络合作用大于类腐殖组分为主的DOM，影响抗生素在湖泊水体中的生物有效性和生态毒性. |
| 关键词: 四环素 溶解性有机质 荧光猝灭 平行因子分析 二维相关图谱 太湖 玄武湖 |
| DOI：10.18307/2018.0413 |
| 分类号: |
| 基金项目:东南大学通识课程项目（1125000131）和中央高校基本科研业务费资助项目（2242017K40041）联合资助. |
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| Interactions of tetracycline and dissolved organic matter from freshwater lakes |
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CAO Chicheng1, WANG Youquan2, ZHANG Qi1, ZHANG Hui1
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1.Key Laboratory of Environmental Medicine Engineering, Ministry of Education, School of Public Health, Southeast University, Nanjing 210009, P. R. China;2.Key Laboratory of Environmental Engineering of Jiangsu Province, College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, P. R. China
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| Abstract: |
| Interactions of tetracycline (TC) with dissolved organic matter (DOM) collected from Lake Taihu and Lake Xuanwu were investigated through fluorescence quenching. Three fluorescent DOM components, fulvic-(C1), tryptophan-(C2), and tyrosine-like (C3) component, were identified in DOM via excitation emission matrix spectra with parallel factor analysis (EEM-PARAFAC). Results from fluorescence quenching titration showed that the fluorescence of 3 components was quenched at different degree by TC through static quenching. When the TC concentration increased to 45.5 μmol/L, the whole florescence of C2 and C3 were almost quenched, while 20% of C1 fluorescence was inaccessible. The quenching also induced conformational changes in DOM molecules. Synchronous fluorescence spectra combined with two dimensional correlation spectroscopy (2D-COS) further revealed that the complexation firstly occurred for tryptophan-like substance, followed by tyrosine-and fulvic-like substance. The associated complexing constants (lgK) of 3 components with TC were in the range of 5.05-5.85, followed the order of C2 > C3 > C1. The strong binding ability of protein-like substances confirmed their prominent role in the TC-DOM complexation. These results highlight the significant impact of DOM on the bioavailability and ecotoxicity of antibiotics in freshwater lakes. |
| Key words: Tetracycline dissolved organic matter fluorescence quenching 2D-COS PARAFAC Lake Taihu Lake Xuanwu |
