Characterization, genomic analysis, and decontamination application of a novel Vibrio phage BUCT787 on salmon fillets

Vibrio spp. are significant zoonotic pathogens in seafood, causing human gastroenteritis and posing challenges to the aquaculture industry. The misuse of antibiotics in aquaculture has led to the rise of antibiotic-resistant strains, necessitating alternative solutions like phages for food safety and pathogen control. Herein, we isolated and characterized a novel lytic Vibrio phage, BUCT787, from salmon aquaculture environments. Genomic analysis revealed that BUCT787 shared only 68% genome-wide coverage and 95.97% sequence identity with Vibrio phage 207E29.1, classifying it as a new member of an unclassified family within the Caudoviricetes order. The phage genome contained 86 predicted open reading frames (ORFs), with only 29 ORFs encoding proteins with known functions. BUCT787 exhibited stability across a wide range of temperatures (4°C-36°C) and pH conditions (4-12). To optimize infection efficiency, the optimal MOI for BUCT787 was determined to be 0.01, and the one-step growth curve revealed a latent period of 13 min, followed by a burst phase of 100 min, with a burst size of 42.1 PFU/cell. Furthermore, we developed a novel phage application platform using aerosolization technology to significantly reduce pathogen levels in closed environments and on seafood products, maintaining the freshness of salmon fillets and meeting GRAS standards. BUCT787 exhibited remarkable inhibitory activities against Vibrio spp., with an inhibition efficiency of 99.9%, and preserved the quality of salmon fillets. These findings establish BUCT787 as a promising biocontrol agent, offering a sustainable solution for enhancing seafood safety, reducing the spread of antibiotic-resistant pathogens, and supporting the sustainability of the aquaculture industry. KEY POINTS: • Isolated a novel lytic Vibrio phage BUCT787 with 68% coverage and 95.97% identity. • Phage BUCT787 showed efficient lytic activity and a wide pH and temperature tolerance range. • Developed a phage aerosolization platform that reduced Vibrio contamination by 99.9% on salmon fillets.