CuminUP60® - a commercially-available high-soluble curcumin exhibits photodynamic fungicidal efficacy against Saccharomyces cerevisiae

Photodynamic technology (PDT) is an emerging non-thermal sterilization and preservation strategy that has garnered considerable attention due to its high efficiency, safety, and residue-free nature. Curcumin is a promising natural, food-safe photosensitizer for antimicrobial photodynamic inactivation. However, its extremely poor water solubility severely limits its practical application in aqueous food systems. In this study, we systematically evaluated the inactivation efficacy and underlying mechanisms of PDT mediated by CuminUP60®, a commercially available, highly water-soluble curcumin complex, against Saccharomyces cerevisiae , a common spoilage microorganism in fruit and vegetable products that causes significant economic losses in the beverage and sauce industries. The results demonstrated that optimized treatment conditions (75 μmol/L CuminUP60® combined with blue light at a dose of 0.396 J/cm 2 ) achieved a 4.12-log reduction in S. cerevisiae colony-forming units. Mechanistic analysis revealed that PDT induced a marked accumulation of intracellular and mitochondrial reactive oxygen species (ROS), leading to mitochondrial membrane depolarization and subsequent depletion of intracellular ATP. This study demonstrates that CuminUP60® is a highly promising natural photosensitizer, providing a novel strategy for the non-thermal control of fungal spoilage in the food industry.