Formulation with zinc acetate enhances curcumin's inherent and photodynamic antimicrobial effects for food preservation

Food spoilage is primarily caused by microbial contamination. Curcumin has attracted attention as a safe and healthy food preservative based on its favorable pharmacological properties and antimicrobial effects. However, the antimicrobial activity of curcumin is moderate. This study proposes a strategy to enhance the efficacy of curcumin by formulating it with zinc acetate. The formulated curcumin, Cur-Zn, exhibited increased antimicrobial activity against multiple food-contaminating bacteria and fungi. With light illumination, the antimicrobial activity of Cur-Zn was further enhanced due to the photodynamic inactivation (PDI) effect. Additionally, Cur-Zn demonstrated higher efficacy in alleviating food contamination by either bacteria or fungi compared to curcumin alone. Furthermore, Cur-Zn more efficiently delayed the spoilage of fresh beef during the long-term storage. Thus, Cur-Zn can be a highly effective food preservative.