Changes and distributions of antibiotic resistance genes in liquid and solid fractions in mesophilic and thermophilic anaerobic digestion of dairy manure

Qiuping Zhang; Jifei Xu; Xiujun Wang; Wenbo Zhu; Xiaoke Pang; Ji Zhao

doi:10.1016/j.biortech.2020.124372

Changes and distributions of antibiotic resistance genes in liquid and solid fractions in mesophilic and thermophilic anaerobic digestion of dairy manure

Bioresour Technol. 2021 Jan;320(Pt A):124372. doi: 10.1016/j.biortech.2020.124372. Epub 2020 Nov 5.

Authors

Qiuping Zhang¹, Jifei Xu², Xiujun Wang¹, Wenbo Zhu¹, Xiaoke Pang¹, Ji Zhao¹

Affiliations

¹ Inner Mongolia Key Laboratory of Environmental Pollution Prevention and Waste Resource Recycle, School of Ecology and Environment, Inner Mongolia University, Hohhot, China.
² Inner Mongolia Key Laboratory of Environmental Pollution Prevention and Waste Resource Recycle, School of Ecology and Environment, Inner Mongolia University, Hohhot, China. Electronic address: Jifeixu@imu.edu.cn.

PMID: 33186839
DOI: 10.1016/j.biortech.2020.124372

Abstract

This study mainly explored the changes and distributions of antibiotic resistance genes (ARGs) in liquid fraction (L_F) and solid fraction (S_F) in anaerobic digestion (AD) of dairy manure. After mesophilic and thermophilic AD, the copy numbers of ARGs in L_F decreased by 0.06-1.80 logs while those in S_F increased by 0.08-7.85 logs, suggesting the enrichment of ARGs in S_F. Statistical analysis elucidated that high total solids promoted the enrichment of ARGs in S_F. The increased abundances of genera such as Ruminofilibacter, Treponema and Sphaerochaeta in S_F were responsible for the enrichment of most ARGs. These insights demonstrated the digested solid had the potential risks to promote the spread of ARGs in the environment, and the digested solid of livestock manure should be post-treated before the application.

Keywords: Anaerobic digestion; Antibiotic resistance genes; Distribution; Liquid fraction; Solid fraction.

MeSH terms

Anaerobiosis
Anti-Bacterial Agents* / pharmacology
Drug Resistance, Microbial / genetics
Genes, Bacterial
Manure*

Substances

Anti-Bacterial Agents
Manure