Control of Vibrio parahaemolyticus in Seafood Using the Combination of Lytic Phages and Citric Acid

<i>Vibrio parahaemolyticus</i> is a key foodborne pathogen in seafood that poses health risks to consumers. The application of phages and organic acids is considered an alternative strategy for controlling bacterial contamination in foods. In the present study, the genome features of five previously isolated virulent <i>V. parahaemolyticus</i> phages (VPpYZU64, VPpYZU68, VPpYZU81, VPpYZU92, and VPpYZU110) were characterized, and their bacteriostatic effects in combination with citric acid were analyzed. Genome sequencing of the five phages showed a total genome length of 76,153-144,768 bp. No virulent or drug-resistant genes were detected in the five phages. Bacterial inhibition testing of salmon fillets stored at 25 °C for 12 h showed that the number of <i>V. parahaemolyticus</i> decreased by 2.02 and 3.84 log CFU/g after treatment with a phage mixture, <i>VPp</i>MIx, and the combination of phage mixture <i>VPp</i>MIx and citric acid. In addition, phage VPpYZU64 combined with 600 μg/mL citric acid exhibited the highest biofilm reduction rate for <i>V. parahaemolyticus</i>. Collectively, our results show that combining phages and citric acid is a natural and efficient method of controlling <i>V. parahaemolyticus</i> growth in seafood.