Effects of thermal treatment on the immunoreactivity and quantification of parvalbumin from Southern hemisphere fish species with two anti-parvalbumin antibodies

Abstract

This study investigates the effects of thermal (wet-heat) treatment on the immunoreactivity and detectability of parvalbumin allergens (PAV) present in diverse southern hemisphere fish species in Australia, utilizing an anti-cod polyclonal antibody (PoAb) and an anti-carp monoclonal antibody (MoAb) as model antibodies. The detectability of different parvalbumins by the anti-cod PoAb was less affected by thermal treatment than the anti-carp MoAb. Compared to the raw (untreated) fish extracts (as reported in our previous study), heat treatment improved the antibody binding to PAVs of some fish species, especially those difficult to detect PAVs from fish species such as Atlantic salmon and yellowfin tuna. Heat treatment significantly improved the correlation between the PAV content and their immunoreactivity for both antibodies (R2 = 0.82 for the anti-cod PoAb and R2 = 0.55 for the anti-carp MoAb). This suggests that thermally processed PAV is a more stable target than their raw counterparts for the ELISA analysis, but it did not alter the order specificity observed with the raw PAVs. Fish species from the order Perciformes showed stronger immunoreactivity to both antibodies; whereas species from Scombriformes, Scorpaeniformes and Tetraodontiformes showed weak or no immunoreactivity.