The Agricultural Green Development Science and Engineering Innovation Team at the Institute of Agricultural Resources and Regional Planning of the Chinese Academy of Agricultural Sciences has recently achieved a groundbreaking milestone. In their pioneering study, they delved into the key metabolic pathways and energetic mechanisms that involved the coupling of electron bifurcation and interspecies electron transfer in methane production during anaerobic digestion. Their research, titled "Coupling electron bifurcation and interspecies electron transfer to mitigate ammonia and acids inhibition," have been published in the journal "Renewable and Sustainable Energy Reviews."

Anaerobic digestion is an important technology for promoting agricultural green development as it allows for the simultaneous utilization of agricultural waste resources and energy recovery. The challenges of ammonia nitrogen and volatile fatty acid inhibition in this process necessitate a deep understanding of microbial community structure and metabolic stability   for sustained methane production. The team's work sheds light on the regulation of microbial metabolism and bioenergetics, addressing a critical gap in current research efforts.

Enhancing interspecies electron transfer through the electron bifurcation mechanism can strengthen the bond between bacteria and methane-producing archaea, thereby enhancing methane production potential under conditions of simultaneous ammonia nitrogen and volatile fatty acid inhibition. This paper provides a comprehensive review of how strengthening electron bifurcation coupled with direct interspecies electron transfer alleviates the synergistic inhibition of ammonia nitrogen and volatile fatty acids. It details the molecular mechanisms involved in ammonia nitrogen and volatile fatty acid inhibition and the strategies centered around interspecies electron transfer. The paper systematically explains the mechanism for alleviating the synergistic inhibition of ammonia nitrogen and fatty acids under energy coupling pathways. This research serves as a reference for studies on regulating interspecies electron transfer and energy coupling pathways under anaerobic digestion inhibition conditions.

Anina James, a postdoctoral researcher at the Institute of Agricultural Resources and Regional Planning of the Chinese Academy of Agricultural Sciences, is the first author of the paper, with Prof. Pan Junting as the corresponding author. The research was supported by the National Key Laboratory for Efficient Utilization of Dryland Farmland in Northern China, the National Modern Agricultural Industry Technology System, the Innovation Engineering Project of the Chinese Academy of Agricultural Sciences, and the Agricultural Science Talent Program of the Chinese Academy of Agricultural Sciences.

Original Article Link: 

https://doi.org/10.1016/j.rser.2024.115166