Comparative persistence of opportunistic Vibrio alginolyticus and major foodborne Vibrio species (Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus) in ready-to-eat seafood under different storage conditions.

Abstract

Vibrio alginolyticus is an opportunistic marine bacterium capable of infecting both humans and aquatic animals, in addition to major foodborne pathogenic Vibrio species (Vibrio cholerae, Vibrio parahaemolyticus, and Vibrio vulnificus). Although these species are increasingly detected in seafood, differences in their persistence under conditions simulating real food systems remain poorly understood. This study investigated the growth, survival, and recovery of V. alginolyticus and compared its behavior with those of the three pathogenic species in ready-to-eat seafood (flatfish, smoked salmon, and salted trout eggs) with different salinities (3.1%, 6.2%, and 11.0%, respectively). Each species was inoculated at two concentrations (1-2 or 4-5 log CFU/g) and stored at 5, 15, and 25 °C for 12 weeks. In low- and moderate-salinity seafood (flatfish and smoked salmon), the four Vibrio species showed broadly similar growth and survival patterns. However, species-specific differences became more evident in high-salinity seafood (salted trout eggs), where V. alginolyticus grew faster and persisted longer, whereas V. vulnificus and V. parahaemolyticus declined more rapidly and V. cholerae showed no detectable growth. Recovery after enrichment under refrigeration further indicated greater persistence of V. alginolyticus than the other species. These findings highlight that multiple environmental factors shape Vibrio persistence in ready-to-eat seafood, with salinity emerging as a particularly influential factor. This study provides comparative insights into opportunistic V. alginolyticus and three pathogenic Vibrio species in real seafood matrices, offering practical information for long-term temperature-control strategies to minimize microbial risks in ready-to-eat seafood.