The transition to a resource-efficient circular economy needs development on alternative sources of energy and materials to decrease our dependency on fossil resources. Through microbial chain elongation, reactor microbiomes convert complex feedstocks into medium-chain carboxylates (MCC), valuable platform chemicals with diverse applications in the energy, agri-food and chemical industries.
This thesis presents open-culture microbial chain elongation processes for the production of MCC from food waste and lactate. Alternative MCC separation approaches are further explored. Potential feedstocks and processing schemes supporting the production of even-chain, odd-chain and branched MCC with lactate as the key electron donor are proposed. Additionally, an outlook is given on the potential and implications of producing MCC-rich products (e.g. feed additives, soil amendments) and sustainable aviation fuels. Lactate-based chain elongation is envisioned as a promising, versatile platform to upcycle nutrient-rich and complex organic residues into a variety of valuable products supporting the development of the circular economy.