Abstract
Lycopene, a natural carotenoid with antioxidant and health-promoting properties, has attracted attention as a valuable compound for the food, pharmaceutical, and cosmetic industries. Conventional production methods based on plant extraction or chemical synthesis are limited by low yields, high costs, and environmental concerns. In this study, the oleaginous yeast Yarrowia lipolytica was engineered as an alternative microbial cell factory for sustainable lycopene biosynthesis using short-chain fatty acids (SCFAs)-such as acetate, butyrate, and propionate-as inexpensive, renewable carbon sources. Four heterologous genes from Pantoea agglomerans (crtI, crtB, crtE, and idi) were codon-optimized and integrated into the Y. lipolytica genome using different expression systems, including the Golden Gate Assembly strategy. Among the tested strains, PS05/4lyc/GGA, characterized by enhanced phospholipid biosynthesis, demonstrated the highest lycopene yield of 462.9 mg/g dry cell weight and a titer of 3.41 g/L on butyrate medium-values comparable to or exceeding those reported for bioreactor-scale fermentations. The results indicate that co-activation of phospholipid and carotenoid biosynthesis pathways creates favorable intracellular conditions for hydrophobic pigment accumulation. Moreover, the use of SCFAs improved acetyl-CoA availability and redirected carbon flux through the mevalonate pathway, enhancing productivity. Strains with elevated membrane lipid biosynthesis also exhibited higher metabolic stability and stress tolerance.