Cold argon plasma-induced aggregated and non-aggregated structural changes in casein and peptidomic insights into allergenicity

Ruiyi Cai; Chin-Ping Tan; Oi-Ming Lai; Yali Dang; Aiming Liu; Ling-Zhi Choeng; Daodong Pan; Lihui Du

doi:10.1016/j.foodchem.2024.142408

Cold argon plasma-induced aggregated and non-aggregated structural changes in casein and peptidomic insights into allergenicity

Food Chem. 2024 Dec 7:468:142408. doi: 10.1016/j.foodchem.2024.142408. Online ahead of print.

Authors

Ruiyi Cai¹, Chin-Ping Tan², Oi-Ming Lai³, Yali Dang¹, Aiming Liu⁴, Ling-Zhi Choeng⁵, Daodong Pan¹, Lihui Du⁶

Affiliations

¹ State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo 315211, China; Zhejiang-Malaysia Joint Research Laboratory for Agricultural Product Processing and Nutrition, Ningbo 315800, China.
² Department of Food Technology, Faculty of Food Science and Technology, Universiti Putra Malaysia, Serdang 43400, Malaysia.
³ Department of Bioprocess Technology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, Serdang 43400, Malaysia.
⁴ Medical School of Ningbo University, Ningbo 315211, China.
⁵ School of Agriculture, Food and Ecosystem Sciences, Faculty of Science, University of Melbourne, Melbourne, Victoria 3010, Australia.
⁶ State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Ningbo 315211, China; Zhejiang-Malaysia Joint Research Laboratory for Agricultural Product Processing and Nutrition, Ningbo 315800, China. Electronic address: dulihui@nbu.edu.cn.

PMID: 39674013
DOI: 10.1016/j.foodchem.2024.142408

Abstract

Casein (CN) is a common allergen that is challenging to avoid in modern foods. The effect of cold argon plasma (CAP) on reducing CN antigenicity was investigated, focusing on alterations in epitope structure and sequence. CAP mainly contains hydroxyl radicals (∙OH). After a 12-min CAP treatment, the result of ELISA demonstrated an 80.46 % reduction in antigenicity. Transmission electron microscopy and electrophoresis revealed that certain CN aggregated, while multispectral analysis indicated that part of CN was fragmented into smaller peptides. The predictive 3D model suggested the disruption of linear epitopes located in the α-helix region might contribute to the reduced allergenicity. The peptide sequences were compared to the linear epitopes predicted by immunoinformatics approaches, revealing some reduction or breakage of key allergic sequences. Meanwhile, amino acids with aromatic side chains and hydrophobic groups were susceptible to CAP-induced modifications. This investigation demonstrated CAP could be beneficial for processing hypoallergenic foods.

Keywords: Antigenicity; Casein; Cold argon plasma; Dielectric barrier discharge; Peptide sequencing.