Harnessing yeasts for sustainable succinic acid production: advances in metabolic engineering and biorefinery integration.

This review highlights the potential of Yarrowia lipolytica and other yeasts as sustainable producers of bio-based succinic acid (SA), a key platform chemical with applications in bioplastics, solvents, and pharmaceuticals. Recent advances in metabolic engineering have substantially improved SA titers, yields, and productivities in yeasts. These improvements were achieved by reconstructing biosynthetic pathways, disrupting gene involved in side-metabolism and/or expressing heterologous genes involved in critical metabolic functions. The use of renewable feedstocks, including crude glycerol, agricultural residues, food waste hydrolysates, and industrial by-products, has shown promise in reducing both production costs and environmental impacts. Innovative downstream separation techniques, such as in situ extraction, membrane filtration, and crystallization, further contribute to process sustainability. Integrating yeast-based SA production into circular biorefineries and adopting continuous production systems are promising strategies for enhancing economic feasibility and minimizing ecological footprints. Although challenges related to scale-up and process integration persist, ongoing advancements in genetic engineering and bioprocessing technologies position yeast-based processes as a viable route for sustainable, large-scale bio-based SA production within a circular bioeconomy framework.