Mechanistic studies of polyphenols reducing the trypsin inhibitory activity of ovomucoid: Structure, conformation, and interactions. (15th May 2023)

• Record Type: Journal Article
• Authors: Cui, Rui; Ji, Shengnan; Xia, Minquan; Fu, Xing; Huang, Xi
• Is Part Of: Food chemistry. Volume 408(2023)
• Publication Date: 2023-05-15
• Subjects: Ovomucoid -- Trypsin Inhibitor -- Polyphenol -- Structure -- Conformation; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2022.135063
• Languages: English
• ISSNs: 0308-8146

Abstract

Graphical abstract: Highlights: EGCG and GA obviously reduced the trypsin inhibitory activity (TIA) of ovomucoid (OVM). EGCG and GA stabilize protein conformation by reducing β-sheet and increasing α-helix content. EGCG and GA bonded to OVM in hydrophobic interactions, causing the decreased TIA of OVM. The quenching mechanism of polyphenols on OVM was static quenching process. Abstract: Ovomucoid (OVM) is a critical anti-nutritional factor in egg, which may reduce nutrient utilization. In this study, the effects of polyphenols on the trypsin inhibitory activity (TIA) of OVM were investigated by exploring the structural changes and interaction mechanisms. The results found that TIA decreased to 62.34% and 90.41% as epigallocatechin gallate (EGCG) and gallic acid (GA) were added individually. EGCG and GA interacted with OVM via static quenching and hydrophobic interaction. They induced a transition of OVM conformation from disorder to order. Infrared and fluorescence quenching analysis showed that the interaction between EGCG or GA and OVM was spontaneous, and hydrophobic interaction was the predominant force. The mechanism suggested that polyphenols affect the protein conformation by spontaneously binding to OVM in hydrophobic interactions, and lowering the TIA through reduced hydrophobicity. In summary, EGCG may be a promising OVM trypsin activity inactivator, which could also guarantee safety of egg products.