@conference{
author = "Prodić, Ivana and Smiljanić, Katarina and Nagl, Christoph and Hoffmann-Sommergruber, Karin and Ćirković-Veličković, Tanja",
year = "2021",
abstract = "Cor a 8 is a relevant allergen that can cause severe allergic reactions. It is a 115 amino acid protein with a molecular mass of 9 kDa and is a member of the non-specific lipida transfer protein family. This allergen is resistant to high temperatures, pH changes, gastric and intestinal enzymes. The main route of exposure is through ingestion. In order to examine its resistance to digestion, we have applied a popular 1.0 INFOGEST protocol [1], specialized for the complete food, which in vitro mimics physiologically relevant conditions of oral-gastric-intestinal digestion. The aim of this study was to compare Cor a 8 resistance to gastric digestion, from both, raw and roasted hazelnuts, before and upon pepsin (gastric) digestion. Stability of the Cor a 8 protein was investigated by simulation of oral and gastric digestion phases, performed with ground raw and roasted hazelnut kernels. Hazelnut proteins were extracted from the digestion mixture and analyzed by 1D and 2D SDS-PAGE, while raw and roasted Cor a 8 western blots were probed with specific anti-Cor a 8 antibodies in 1D and 2D immunoblots. The electrophoretic patterns of the raw and roasted extracts were similar. 1D SDS PAGE profiles demonstrated high stability of Cor a 8 against enzymatic treatments. Control samples of Cor a 8 from raw and roasted hazelnut extracts migrated as a single band at around 12 kDa in 1D immunoblot. However, in case of roasted hazelnut, the protein showed a slightly lower capacity to bind specific anti-Cor a 8 antibody, as compared to raw hazelnut extract. In 2D immunoblot, with higher resolution, specific antibody binding was decting a significant and noticeable smear in the basic region indicating a range of different protein variants. This was more pronounced detectable in the case of roasted sample upon digestion, pointing to a mix of variants in this allergen batch. It has been suggested that the allergenicity of the Cor a 8 is almost insensitive to temperature. The allergen is stable even after digestion and roasting processes up to 140˚C. We hypothesize that a lipid-rich food matrix delays extraction of proteins, thereby delaying their gastrointestinal digestion, which may affect allergen sensitizing capacity and clinical symptoms.",
publisher = "Sociedade Portuguesa de Química",
journal = "Book of Abstracts of the XXI EuroFoodChem Congress",
title = "Allergenicity assessment of Cor a 8 from raw and roasted hazelnut upon oral-gastric digestion phase of INFOGEST protocol",
pages = "126-126",
url = "https://hdl.handle.net/21.15107/rcub_cherry_5762"
}
