Detection of allergenic parvalbumin of Atlantic and Pacific herrings in fish products by PCR

Abstract

The conventional polymerase chain reaction (PCR) method to detect the major allergenic protein parvalbumin beta 2 of Atlantic herring (Clupea harengus) and Pacific herring (Clupea pallasii) was developed. The specific set of primers for the amplification of the partial genomic sequence of the pvalb 2 gene encoding the main fish allergen of both herrings was designed and applied to the investigation of 24 commercial fish products. The targeted amplicon size was 189 bp of pvalb 2 gene of Atlantic herring and Pacific herring. As the internal amplification control, the DNA of 18S rRNA gene for eukaryotes (141 bp) was successfully used. The specificity of designed primer pair using 26 various fish species was assessed. The intrinsic detection limit was 10 pg µl(-1) of the present specific DNA. Atlantic herring or Pacific herring allergenic parvalbumins were detected in 22 investigated fish products in conformity with the package declaration. Two fish products were negative in spite of the declaration. The proposed PCR method is specific enough and can be used for the detection of Atlantic and Pacific herrings' major allergen parvalbumin beta 2 in fish food products.