Removal of extracellular antibiotic resistance genes using magnetic biochar/quaternary phosphonium salt in aquatic environments: A mechanistic study

JOURNAL OF HAZARDOUS MATERIALS

卷:411

Article

Fu, Yuhao^1,2  Wang, Fang^1,2  Sheng, Hongjie^1,2  Hu, Fang^1,2  Wang, Ziquan^1,2  Xu, Min^1,2  Bian, Yongrong^1,2  Jiang, Xin^1,2  Tiedje, James M.³ 

[1] Chinese Acad Sci, Inst Soil Sci, CAS Key Lab Soil Environm & Pollut Remediat, Nanjing 210008, Peoples R China

[2] Univ Chinese Acad Sci, Beijing 100049, Peoples R China

[3] Michigan State Univ, Dept Plant Soil & Microbial Sci, Ctr Microbial Ecol, E Lansing, MI 48824 USA

关键词: Magnetic biochar;    Quaternary phosphonium salt;    Extracellular antibiotic resistance gene;    Electrostatic adsorption;    Oxidative damage;   

DOI  :  10.1016/j.jhazmat.2021.125048

来源: Elsevier

【 摘 要 】

The proliferation and spread of antibiotic resistance genes (ARGs) is becoming a worldwide crisis. Extracellular DNA encoding ARGs (eARGs) in aquatic environment plays a critical role in the dispersion of antimicrobial resistance genes. Strategies to control the dissemination of eARGs are urgently required for ecological safety and human health. Towards this goal, magnetic biochar/quaternary phosphonium salt (MBQ), was used to investigate the efficiency and removal mechanism for eARGs. Magnetic biochar modified by quaternary phosphonium salt enhanced the adsorption capacity of extracellular DNA to approximately 9 folds, compared to that of the unmodified. DNA adsorption by MBQ was mainly dominated by chemisorption in heterogeneous systems and was promoted in acidic and low-salt environment. The generation of ?OH and MBQ colloid jointly cleaved DNA into fragments, facilitating the adsorption of the phosphate backbone of DNA onto MBQ through electrostatic force as well as the conformational transition of DNA. Furthermore, quantification of extracellular DNA after MBQ was applied in water demonstrated that over 92.7% of resistance genes were removed, indicating a significantly reduced risk of propagation of antimicrobial resistance in aquatic environments. These findings have a practical significance in the application of MBQ in mitigating the spread of ARGs in aquatic environment.

【 授权许可】

Free