Exploring the combination characteristics of dissolved organic matter with erythromycin in a soil infiltration system

ABSTRACT

Erythromycin (ERY), as a common macrolides antibiotic, is widely used for sterilisation and disinfection of humans or livestock whose migration and transformation in the surface water environment are significantly related to dissolved organic matter (DOM). The characteristics of DOM can be greatly influenced by the complexation between ERY with itself in soil infiltration system. Using spectroscopic techniques (excitation-emission matrices, parallel factor analysis, Fourier infrared spectroscopy, and synchronous fluorescence spectroscopies) to explore the complexation properties of each DOM component with ERY in the system. The binding order of ERY with DOM functional groups was determined by two-dimensional correlation spectroscopy combined with FTIR. The amide I band v(C = O) exhibited stronger binding affinity. After the treatment, the DOM fluorescence intensity sharply decreased and the ERY concentration declined by 88.36%. Thus, synchronous degradation may occur between them. The result of synchronous fluorescence spectroscopy integrated with two-dimensional correlation spectroscopy indicated that the complexation sequencing and ability of DOM with ERY can be changed by a soil infiltration system. There are more binding sites exhibited in DOM with ERY in effluent than influent. A protein-like component of DOM showed priority binding order and more stable binding with ERY and had the highest Log K_M value of 3.61. These results demonstrated that the binding of DOM with ERY in a soil infiltration system could take out most fluorescent DOM, and reduce the concentration and risk of ERY in the surface water body.

GRAPHICAL ABSTRACT

KEYWORDS:

• Dissolved organic matter
• erythromycin
• agricultural non-point sources
• low-impact development facilities
• spectral techniques

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

This manuscript includes all the generated or analysed data. If any other data is required related to this article that can be provided by the corresponding author on reasonable request.

Ethics approval

This manuscript does not involve researching about humans or animals.

Author contributions

All of the authors consented to participate in the drafting of this manuscript. All of the authors consented to publish this manuscript. Yiwen Pang: Investigation, material preparation, data collection and analysis. LinXiao Zhai: Investigation, material preparation, data collection and analysis. Yingying Kou: Study conception, design, supervision and writing-review & editing. DongHai Yuan: Funding acquisition, resources, supervision and writing-review & editing. The first draft of the manuscript was written by Yiwen Pang and LinXiao Zhai. All authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

Additional information

Funding

This work is supported by the National Natural Science Foundation of China (52170097), the National Water Pollution Control and Management Technology Major Project (2018ZX07110005).