关键词: 小清蛋白；加工；BLAB/c小鼠模型；致敏性

Abstract: In this study, silver carp muscle was processed into fish cakes by heating, autoclaving, Lactobacillus paracasei fermentation, or L. paracasei fermentation combined with autoclaving. Changes in the immunogenicity and secondary structure of parvalbumin (PV) from fish cakes were evaluated by enzyme-linked immunosorbent assay (ELISA) and Fourier transform infrared (FTIR) spectroscopy. The effect of processing methods on the allergenicity of PV from fish cakes in BALB/c mice was analyzed in terms of allergy symptom scores, and changes in serum immunoglobulin E (IgE) antibody, histamine and cytokine levels. The results showed that compared with heating, autoclaving, L. paracasei fermentation and their combination reduced the reduction rate of PV immunoglobulin G binding capacity from fishcakes by 50.6%, 34.7% and 68.5%, respectively. Compared with natural PV (from silver carp muscle), the α-helix content was reduced by 10.7%, 13.3% and 17.3%, and the β-sheet content was increase by 7.8%, 5.1% and 14.8% by autoclaving, L. paracasei fermentation and their combination, respectively, while there was no significant change in the heating group. All processing methods except heating alleviated allergic symptoms in sensitized mice, and significantly reduced the serum levels of histamine and Th2 cytokines including interleukin-4 (IL-4), IL-5 and IL-13 (P < 0.05). Serum IgE antibody levels were significantly higher in the heat treatment group than in the other treatment groups (P < 0.05), and L. paracasei fermentation combined with autoclaving was the most effective in reducing the allergenicity of PV. In summary, the single treatments were less effective than their combination in reducing the α-helix content, increasing the folding degree, and mitigating the immunogenicity and allergenicity of PV, but they all alleviated Th2 cell responses in immunized mice, in turn inhibiting allergic reactions. Among them, autoclaving combined with fermentation had the most significant effect on the immunogenicity and allergenicity of the major fish allergen PV.

Key words: parvalbumin; processing; BALB/c mouse model; allergenicity