Abstract:The hemolytic activity of the metabolites produced by V. parahaemolyticus (Vp) in different food matrices and their toxicity on mice organs were analyzed. Shrimp, oyster, freshwater fish, beef, and egg-fried rice were inoculated with the ATCC33847 strain and incubated. After centrifugation and filtration, a plate hemolysis assay was used to detect the hemolytic activity of metabolites produced by Vp in food matrix filtrates, and mice were fed with different doses of the filtrates of the above food matrices by gavage. Mice were sacrificed, and organ coefficients (OC) and serum biochemical parameters were measured. The filtrate from egg-fried rice had the highest hemolytic activity, but did not produce greater toxicity to mice than other filtrates. In mice fed with the Vp-contaminated shrimp and oyster filtrates, the stomach and intestinal OC were significantly increased (p < 0.05) compared with other food matrix filtrates. The metabolites produced by Vp in five food matrices caused various degrees of changes in albumin (ALB), alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and blood urea nitrogen (BUN) (p < 0.05) in mice. The shrimp filtrate showed a stronger effect on the indicators of mouse liver function than other filtrates and had a stronger liver toxicity, while oyster and freshwater fish filtrates showed a greater toxicity to kidney. These results suggest that Vp may produce different virulence factors in different food matrices, therefore causing different toxic damage to the organs in mice.
