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Engineering >> 2022, Volume 16, Issue 9 doi: 10.1016/j.eng.2021.03.025

Microbial Electrosynthesis for Producing Medium Chain Fatty Acids

a Fujian Provincial Key Laboratory of Soil Environmental Health and Regulation, College of Resources and Environment, Fujian Agriculture and Forestry University, Fuzhou 350002, China
b State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
c College of Architecture and Environment, Sichuan University, Chengdu 610065, China
d Department of Civil and Environmental Engineering & Andlinger Center for Energy and the Environment, Princeton University, Princeton, NJ 08544, USA

Received:2020-07-17 Revised:2021-01-25 Accepted: 2021-03-03 Available online:2021-07-31

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Microbial electrosynthesis (MES) employs microbial catalysts and electrochemistry to enhance CO2 bioconversion to organics with concurrent waste biorefining capability. The aim of this review is to comprehensively discuss the current state of the art and prospects of medium chain fatty acids (MCFAs) production in MES from CO2 and waste organics. Fundamental mechanisms and development of MCFAs production via conventional fermentation are introduced as well. Studies on MCFAs production in MES are summarized, highlighting the strategy of multiple-electron donors (EDs). Challenges for MCFAs production in MES from CO2 are presented, and the primary discussions included methanogenesis inhibition, adenosine triphosphate (ATP) limitations of acetogens, and production of limited EDs via solventogenesis. Possible applications of electrochemical approaches to promote the bioconversion of actual waste materials with MCFAs production are analyzed. Finally, future directions are explored, including multi-stage reactions, substrate supply, product extraction, and microbial pathways.


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