Effect of Fish Species and Fermentation on Immunological Properties of Allergens from Freshwater Fish

Abstract

With increased freshwater fish consumption in China, hypersensitivity reactions of consumers have become more and more common, most of which are mediated by IgE antibodies and manifest as urticaria, asthma, diarrhea, and even life-threatening anaphylaxis. More attention paid to immunological properties of freshwater fish is therefore necessary. The aim of this study was to investigate IgE/IgG binding capacity of seven most popular freshwater fish in China and evaluate the effect of fermentation on freshwater fish allergens, especially parvalbumin. Patient sera and monoclonal anti-parvalbumin antibody were used in indirect ELISA and western blotting to detect the IgE and IgG binding capacity. Different fermentation conditions, including different starter cultures, fermentation time, concentration of starter cultures, NaCl and glucose, were studied to evaluate the effect of fermentation on immunological properties of fish allergens. The results showed that black carp had the highest IgE binding capacity (OD450nm:0.821). Fermentation with Lactobacillus plantarum reduced the IgG (76.12±4.73%) and IgE-binding (39.71±6.18%) capacity to a larger extent than fermentation with Staphylococcus xylosus and Saccharomyces cerevisiae. The results showed more hypersensitivity could be reduced with longer fermentation time. The reduction rate was the highest with an incubation concentration of Lactobacillus plantarum at 1.5% (v/w). A change in the NaCl content affected IgG/IgE binding capacities of fish allergens during fermentation, while a change in glucose had less impact. In conclusion, fermentation can be applied to the development of low-sensitivity freshwater fish products with further experiments.