A Multi-Strain Phage Cocktail for Effective Biocontrol of Pathogenic Vibrio Species in Seafood

The emergence of multidrug-resistant Vibrio alginolyticus and Vibrio parahaemolyticus poses significant challenges to aquaculture health management and the safety of seafood products. In this study, we developed a phage-based biocontrol strategy to address this issue. Thirty-seven lytic phages were isolated, from which a cocktail of five phages (PVa1, PVa2, PVp1, PVp2, and PVp6) with complementary host ranges was formulated. Comprehensive characterization revealed that these phages possess short latent periods (~10 min), large burst sizes (>7.4 × 103 PFU/cell), and high stability under a broad range of pH (4–11) and thermal (30–70 °C for most) conditions. The phage cocktail demonstrated strong efficacy in inhibiting multiple Vibrio strains in vitro. In a proof-of-concept evaluation on raw tuna fillets, it reduced bacterial counts by 1–2 log. Our findings highlight the potential of this phage cocktail as an effective, safe, and sustainable biocontrol agent for use in aquaculture systems and for enhancing the safety of seafood products.