Advancements in photodynamic inactivation: A comprehensive review of photosensitizers, mechanisms, and applications in food area

Abstract

Food microbial contamination results in serious food safety issues and numerous food loss and waste, presenting one of the most significant challenges facing the global food system. Photodynamic inactivation (PDI) technology, which combines light and photosensitizers (PS) to provide antimicrobial effects, is an ideal nonthermal antimicrobial technique for the food industry. This review provides a comprehensive overview of PDI technology, beginning with the fundamental photoactivation principles of PS and the pathways of photoinduced reactive oxygen species (ROS) generation. PS is the most critical factor affecting PDI efficiency, which is categorized into three types: organic, metal oxide-, and carbon-based. This review systemically summarizes the photophysical properties, in vitro PDI performances, potential enhancement strategies, and the advantages and limitations of each type of PS. Furthermore, the antimicrobial mechanisms of the PDI technologies are analyzed at both microscopic and molecular levels. Finally, the current applications of PDI in various food systems are discussed, along with the associated challenges and opportunities. Overall, this review offers crucial insights into optimizing and advancing PDI technology, highlighting key challenges and suggesting future research directions to enhance the effectiveness and scalability of PDI for diverse food applications.