CO₂-DERIVED FERMENTATION PATHWAYS FOR SUSTAINABLE PROTEIN AND LIPID PRODUCTION IN FOOD AND FEED

Industrial biogenic CO₂ streams are an underutilized carbon resource, while the food and feed sectors need scalable alternatives to conventional protein and lipid sources. Here, we present a modular CO₂-to-nutrients platform that couples autotrophic gas fermentation with acetate-based microbial upgrading. In the first stage, a thermophilic acetogenic bacterium converts CO₂ and H₂ into acetate. Acetate is subsequently recovered and concentrated to provide a readily handled C2 platform intermediate for downstream biomanufacturing [1,2]. This design separates gas conversion from product formation and enables the same CO₂-derived intermediate to feed complementary production routes. In the protein route, filamentous fungi are cultivated on acetate to generate protein-rich biomass with a favorable amino-acid profile for food and feed applications [3]. In the lipid route, marine thraustochytrid protists are cultivated under fed-batch conditions to produce intracellular single-cell oils, including omega-3 fatty acids [4]. For both routes, the process chain encompasses upstream cultivation, acetate handling, fermentation optimization, downstream biomass recovery and product characterization. The work demonstrates the integration of CO₂ conversion with acetate-driven production of two nutritionally relevant ingredient classes. Beyond the individual products, the platform provides flexibility: carbon captured as acetate can be directed towards protein-rich biomass or lipid-rich microbial oils according to market requirements and process performance. Coupling efficient gas fermentation with robust downstream cell factories therefore offers a practical route to resource-efficient, circular and scalable production of sustainable food and feed ingredients.