Insight into the interaction between trimethoprim and soluble microbial products produced from biological wastewater treatment processes

作     者：Runze Xu Fang Fang Longfei Wang Jingyang Luo Jiashun Cao Runze Xu;Fang Fang;Longfei Wang;Jingyang Luo;Jiashun Cao

作者机构：Key Laboratory of Integrated Regulation and Resource Development on Shallow LakesMinistry of EducationCollege of EnvironmentHohai UniversityNanjing 210098China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2023年第124卷第2期

页      面：130-138页

核心收录：

学科分类：0710[理学-生物学] 083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 0703[理学-化学] 0836[工学-生物工程] 0701[理学-数学] 0702[理学-物理学] 

基　　金：supported by the National Natural Science Foundation of China (Nos. 51878244 and 52170032) the the Fundamental Research Funds for the Central Universities (No. B200202101) the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), China 

主　　题：Activated sludge process Interaction mechanism Antibiotics Soluble microbial products(SMP) Spectral methods 

摘      要：Soluble microbial products(SMPs),dissolved organic matter excreted by activated sludge,can interact with antibiotics in wastewater and natural water bodies.Interactions between SMPs and antibiotics can influence antibiotic migration,transformation,and toxicity but the mechanisms involved in such interactions are not fully understood.In this study,integrated spectroscopy approaches were used to investigate the mechanisms involved in interactions between SMPs and a representative antibiotic,trimethoprim(TMP),which has a low biodegradation rate and has been detected in wastewater.The results of liquid chromatography-organic carbon detection-organic nitrogen detection indicated that the SMPs used in the study contained 15% biopolymers and 28% humic-like substances(based on the total dissolved organic carbon concentration)so would have contained sites that could interact with TMP.A linear relationship of fluorescent intensities of tryptophan protein-like substances in SMP was observed(R^(2)0.99),indicating that the fluorescence enhancement between SMP and TMP occurred.Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy indicated that carboxyl,carbonyl,and hydroxyl groups were the main functional groups involved in the interactions.The electrostatic andπ-πinteractions were discovered by the UV-vis spectra and 1H nuclear magnetic resonance spectra.Structural representations of the interactions between representative SMP subcomponents and TMP were calculated using density functional theory,and the results confirmed the conclusions drawn from the 1H nuclear magnetic resonance spectra.The results help characterize SMP–TMP complexes and will help understand antibiotic transformations in wastewater treatment plants and aquatic environments.