Beyond the farm: Making edible protein from CO2 via hybrid bioinorganic electrosynthesis

•We realized CO2 to protein in a two-stage bioinorganic electrosynthesis system•We clarified how key factors of inflow and voltage affected this bioconversion•We revealed the importance O2-level control for maximizing production•This process with renewable feedstocks is independent conventional agriculture The rapid growth global population will double demand by 2050. However, ways production need large occupation arable land are associated negative environmental impacts such as high greenhouse gas emissions, water pollution, deforestation. This proof-of-concept study aims develop investigate that combines strengths microbial electrochemistry metabolisms convert surplus electricity into single-cell protein. results may provide insights developing an alternative approach step forward farming high-quality using free from land, which aligns Sustainable Development Goals (2, 12, 13, 15). Climate change food shortage two defining challenges coming decades. Considering approaches associate sources rely on inexhaustible substrates/energy should be pursued. In study, we propose can first excessive methane then synthesize With external 3.5 V rate 50 mL·d?1, it was possible produce methanotrophic biomass 118.7 ± 9.2 mg·L?1 amino acids mass content 54.6% 8.3%, resulting nitrogen assimilation conversion efficiency 91.0% 1.3% 71.0%. applied voltages, rates, O2 supply were found affect significantly. proved production. increasing level carbon dioxide (CO2) atmosphere consequence fossil fuel consumption causes serious climate changes. Besides preventing depletion fuels, development efficient cost-effective technologies capture utilization (CCU) could potentially bring us economic benefits.1Von Der Assen N. Jung J. Bardow A. Life-cycle assessment utilization: avoiding pitfalls.Energy Environ. 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