The role of substrate types and substrate microbial community on the fate of antibiotic resistance genes during anaerobic digestion Junya Zhang a, b, c, *, 1 , Tiedong Lu d, 1 , Peihong Shen d , Qianwen Sui a, b, c , Hui Zhong a, b, c , Jibao Liu a, b, c , Juan Tong a, b, c , Yuansong Wei a, b, c, ** a State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China b Department of Water Pollution Control Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing,100085, China c University of Chinese Academy of Sciences, Beijing, 100049, China d College of Life Science and Technology, Guangxi University, Nanning, 530005, Guangxi, China highlights graphical abstract  Substrate types significantly influ- enced the ARGs fate during anaerobic digestion.  The influence from the substrate microbial community on the ARGs fate was limited.  The ARGs in the substrates them- selves contributed little to the ARGs fate.  The dominant factors influencing the separate ARGs were determined.  Nutrient variance led to microbial community variance that dominated ARGs fate. article info Article history: Received 17 December 2018 Received in revised form 29 April 2019 Accepted 4 May 2019 Available online 8 May 2019 Handling Editor: A Adalberto Noyola Keywords: Antibiotic resistance genes Anaerobic digestion Substrate types abstract Anaerobic digestion (AD) is regarded as a promising technology in energy recovery and the spread mitigation of antibiotic resistance. However, the performance of AD is dependent on various factors, and substrate type is one of the most important. In this study, the fate of antibiotic resistance genes (ARGs) response to the substrate types was investigated, and three typical environmental reservoirs of ARGs (pig manure, chicken manure and sewage sludge) were selected. The role of substrate microbial community on the fate of ARGs was clarified through the comparison between the AD of the substrates with and without a prior autoclave-disinfected step. Results showed that substrate types significantly influenced the fate of ARGs, while the influence from the substrate microbial community was limited. The con- centration of antibiotics, the horizontal gene transfer reflected by intI1 and co-selection from heavy metals reflected by metal resistance genes (MRGs) were all reduced effectively. Microbial community varied from substrate types and dominated the ARGs fate concerning the standardized total effects through the mantel test and SEM analysis. The fate of tetX, ermF, tetM and ermB was mainly determined by the physicochemical parameters and the phyla of Firmicutes and Bacteroides. The phyla of * Corresponding author. University of Chinese Academy of Sciences, Beijing, 100049, China. ** Corresponding author.State Key Joint Laboratory of Environmental Simulation and Pollution Control, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, China. E-mail addresses: jyzhang@rcees.ac.cn (J. Zhang), yswei@rcees.ac.cn (Y. Wei). 1 Junya Zhang and Tiedong Lu contributed equally to this work. Contents lists available at ScienceDirect Chemosphere journal homepage: www.elsevier.com/locate/chemosphere https://doi.org/10.1016/j.chemosphere.2019.05.036 0045-6535/© 2019 Elsevier Ltd. All rights reserved. Chemosphere 229 (2019) 461e470