Mechanism of action of single and mixed antibiotics during anaerobic digestion of swine wastewater: Microbial functional diversity and gene expression analysis

• Published in: Environmental research 2023-02, Vol.219, p.115119-115119, Article 115119
• Main Authors: Tang, Taotao, Liu, Min, Du, Ye, Chen, Ying
• Format: Article
• Language: English
• Subjects: Acetogenesis; Acidogens; Anaerobic digestion; Anaerobiosis; Animals; Anti-Bacterial Agents - pharmacology; Bioreactors; Gene Expression Profiling; Methane; Methanogenic pathways; Mixed antibiotics; Sewage; Swine; Wastewater
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2022.115119

The mechanism by which antibiotics in swine wastewater affect anaerobic digestion (AD) remains unclear. Herein, we investigated how single and mixed antibiotics affect AD in swine wastewater. Both single and mixed antibiotics stimulated methane production at actual concentrations of 0.5–2 mg/L. Low-dose antibiotics (0.5 mg/L) exerted the most significant stimulatory effect on methane production, which increased by 211.63% (single) and 60.93% (mixed), respectively. However, an increased dose decreased the stimulatory effect on methane production. Overall, single antibiotics were more beneficial for methane production than mixed antibiotics since single antibiotics could promote the conversion of propionic and butyric acid, while mixed antibiotics inhibited the process. Microbial community analysis showed that single and mixed antibiotics could also lead to large changes in functional acidogens, ultimately leading to changes in methanogenic pathways. •Single antibiotic could stimulate methane production better than mixed antibiotics.•Acidogenesis-related bacteria was more easily enriched at single antibiotic.•Both single and mixed antibiotics could promote Methanosaeta enrichment.•The methanogenic pathways were different under single and mixed antibiotic stress.