Impacts of biochar on anaerobic digestion of swine manure: Methanogenesis and antibiotic resistance genes dissemination

• Published in: Bioresource technology 2021-03, Vol.324, p.124679-124679, Article 124679
• Main Authors: Yang, Shuo, Chen, Zhiqiang, Wen, Qinxue
• Format: Article
• Language: English
• Subjects: Anaerobic digestion; Anaerobiosis; Animals; Anti-Bacterial Agents - pharmacology; Antibiotic resistance genes; Biochar; Charcoal; Direct interspecies electron transfer; Drug Resistance, Microbial; Genes, Bacterial; Manure; Swine; Swine manure
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2021.124679

[Display omitted] •ARGs and intI1 were effectively reduced with biochar addition in AD.•Biochar enhanced methanogenesis because robust DIET chain was established.•Defluviitoga, Thermovirga and Cloacibacillus participated in DIET with Methanothrix.•ARGs variation was not directly affected by biochar but driving by intI1.•Biochar addition in AD could improve both methane yield and ARGs removal. This work aimed to study the effects of biochar on methanogenesis and antibiotic resistance genes (ARGs) fate during anaerobic digestion (AD) of swine manure (SM) was investigated. Under the optimal biochar dosage of 5–10%, methane yield was significantly improved by 25%, ascribing to the enhancement of direct interspecies electron transfer (DIET). Biochar addition alleviated the need of cytochrome-c as interspecies electron connection components and enriched the microbes involved in DIET. Defluviitoga, Thermovirga and Cloacibacillus were dominant with biochar addition and might participate in DIET together with Methanothrix. The abundance of parC, tetX, blaCTX-M, blaTEM, aac(6′)-Ib-cr, ermB and tetW were significantly reduced in biochar treatments and intI1 removal increased by 15% in B-5% than the control. Structural equation models demonstrated that intI1 (λ = 0.59, P