Biofuel synthesis from carbon dioxide via a bio-electrocatalysis system

Biofuel produced by coupling electrochemical carbon dioxide (CO₂) conversion and microbial fermentation is one of the most viable alternatives to fossil fuels. It provides an effective route to mitigate global climate change and the energy crisis. In this study, a bio-electrocatalysis system was proposed in which acetic acid and formic acid were continuously catalyzed by solid electrolyte reactors and provided the carbon backbone and reducing equivalent, respectively, for the biosynthesis of β-farnesene in engineered Yarrowia lipolytica. The addition of inexpensive polyphosphates aids in the regeneration of intracellular ATP. The final engineered strain was able to accumulate a β-farnesene titer of 14.8 ± 0.23 g L⁻¹ from CO₂. The overall energy efficiency of the described bio-electrocatalysis system for biofuel production was calculated to be ∼0.75%.