Enabling the carbon loop with economical C1-based medium-chain fatty acid biomanufacturing

Abstract

Medium-chain fatty acids (MCFAs) are critical industrial chemicals, yet their production predominantly relies on fossil fuels or edible feedstocks, posing a trade-off between decarbonization goals and food security. While one-carbon (C1) substrates offer a promising alternative, a comprehensive sustainability and economic assessment is lacking. Here, we develop a coupled life cycle assessment and techno-economic analysis framework that integrates bioprocess parameters, regional grids, and carbon policy constraints to evaluate C1-based MCFA biomanufacturing. The results demonstrate that CO₂-based routes achieve a 39% lower global warming potential than lignocellulosic alternatives, driven by carbon sequestration and avoidance of energy-intensive pretreatment, but subject to renewable energy integration. Economically, C1-based production becomes cost-competitive for high-value MCFAs, with carbon taxes in policy-advanced regions cutting costs by ∼20%. Fermentation yield and feedstock costs are the most critical levers for commercialization. This work establishes a transferable quantitative framework to guide carbon-neutral MCFA production and advance C1 biomanufacturing and the circular bioeconomy.