title: Tolerance response to in situ ammonia stress in a pilot-scale anaerobic digestion reactor for alleviating ammonia inhibition.
abstract: The anaerobic digestion (AD) of protein-rich substrates is generally inhibited by ammonia. In this study, ammonia-tolerant acclimation was exposed to a stepwise in situ ammonia stress during the continuous AD of solid residual kitchen waste by using a continuous stirred tank reactor with a 50 L active volume. The reactor worked well during the acclimation process, with an average daily biogas production of 58 L/d, an effluent soluble chemical oxygen demand of 7238 mg/L, a volatile fatty acid (VFA) content of 578 mg/L, and a VFA/alkalinity ratio of less than 0.4. Moreover, ammonia stress enhanced the activity of Coenzyme F420. The results of high-throughput 16S rDNA sequencing showed that ammonia stress increased the relative abundance of Firmicutes bacteria and hydrogenotrophic methanogens but decreased the abundance of acetotrophic methanogens. This microbial community shift was proposed to be an in situ response strategy for ammonia stress adaptation.
authors.affiliation: School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing 314001, China.
authors.forename: Shumei
authors.initials: S
authors.lastname: Gao
authors.affiliation: School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Jiangnan University, Wuxi 214122, China.
authors.forename: Mingxing
authors.initials: M
authors.lastname: Zhao
authors.affiliation: School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Jiangnan University, Wuxi 214122, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen
authors.affiliation: School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Jiangnan University, Wuxi 214122, China.
authors.forename: Meijuan
authors.initials: M
authors.lastname: Yu
authors.affiliation: School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Jiangnan University, Wuxi 214122, China. Electronic address: wqruanjn@gmail.com.
authors.forename: Wenquan
authors.initials: W
authors.lastname: Ruan
mesh_terms: D000641:Ammonia / Q000494:pharmacology*; D000693:Anaerobiosis / Q000187:drug effects*; D001419:Bacteria / Q000378:metabolism; D056804:Biofuels / Q000382:microbiology; D057919:Biological Oxygen Demand Analysis; D019605:Euryarchaeota / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000378:metabolism*; D008697:Methane / Q000096:biosynthesis; D012722:Sewage / Q000382:microbiology*
chemical_list: D056804:Biofuels; D005232:Fatty Acids, Volatile; D012722:Sewage; D000641:Ammonia; D008697:Methane
keywords: Acclimation; Ammonia inhibition; Ammonia tolerance response; Anaerobic digestion; Hydrogenotrophic methanogens