Enhanced Expression of Cs CCD2 Enables Highly Efficient Crocetin Production in Yarrowia lipolytica

Crocetin, a bioactive carotenoid derivative from saffron, exhibits antioxidant, anti-inflammatory, and metabolic regulatory properties. Its low natural abundance and limited extraction production hinder large-scale production. Microbial synthesis offers a promising alternative but is constrained by low carotenoid cleavage dioxygenase (CCD2) expression. Here, we engineered a zeaxanthin-producing <i>Yarrowia lipolytica</i> strain to enhance <i>Cs</i>CCD2 expression via fermentation temperature opt