The photodynamic inactivation of common pathogenic (Vibrio parahaemolyticus) and spoilage (Shewanella putrefaction) bacteria in aquatic products was investigated using curcumin as a photosensitizer. Viable cell counts, cell regrowth capacity, cell surface morphology, reactive oxygen species (ROS) level, biofilm biomass and cell viability were detected before and after photodynamic treatment, and the structural parameters of biofilms were further analyzed. The results showed that when the final concentration of curcumin was 3.0 or 10 μmol/L, and the illumination time was 8 min, the colony number of V. parahaemolyticus and S. putrefaciens were reduced by more than 7 (lg(CFU/mL)). The antibacterial mechanism was by producing a large amount of ROS, leading to the breakdown of the bacterial cell wall and eventually cell lysis and death. In addition, when the illumination time was 60 min, the eradication rates of V. parahaemolyticus and S. putrefaciens biofilms were about 70% and 62% for curcumin concentrations of 30 and 50 μmol/L, respectively. This study may provide new ideas for the design of a new photodynamic technology (PDT) for use in the food industry.

Aquatic products are rich in polyunsaturated fatty acids and high-quality proteins, which are very susceptible to spoilage during storage, so the development of new preservation technologies to extend the shelf life of aquatic products has become a hotspot in current research. Photodynamic inactivation (PDI) technology, as a new and efficient means of inactivating microorganisms, has shown great potential for application in the field of aquatic product preservation. In this article, we elaborate on the mechanism of PDI technology in the preservation of aquatic products, discuss the factors affecting the preservation effect of PDI on aquatic products, and introduce the methods for its evaluation. In addition, we present a systematic review of the application of PDI in the preservation of fish, crustaceans, shellfish and other aquatic products. On this basis, we provide an outlook on the development of new photosensitizers and the combined application of PDI technology with other preservation technologies, aiming to provide a basis for promoting the application and development of PDI technology in the field of aquatic product preservation.