Endogenous reactive oxygen species (ROS)-driven protein oxidation regulates emulsifying and foaming properties of liquid egg white

Jiayi Li; Ziyuan Wang; Nan Xiao; Shanguang Guo; Minmin Ai

doi:10.1016/j.ijbiomac.2024.131843

Endogenous reactive oxygen species (ROS)-driven protein oxidation regulates emulsifying and foaming properties of liquid egg white

Int J Biol Macromol. 2024 Apr 24;268(Pt 1):131843. doi: 10.1016/j.ijbiomac.2024.131843. Online ahead of print.

Authors

Jiayi Li¹, Ziyuan Wang¹, Nan Xiao¹, Shanguang Guo¹, Minmin Ai²

Affiliations

¹ The National Center for Precision Machining and Safety of Livestock and Poultry Products Joint Engineering Research Center, College of Food Science, South China Agricultural University, 510642, China.
² The National Center for Precision Machining and Safety of Livestock and Poultry Products Joint Engineering Research Center, College of Food Science, South China Agricultural University, 510642, China; Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University, Guangzhou 510642, China. Electronic address: scauaiminmin@scau.edu.cn.

PMID: 38663701
DOI: 10.1016/j.ijbiomac.2024.131843

Abstract

Highly oxidative reactive oxygen species (ROS) attack protein structure and regulate its functional properties. The molecular structures and functional characteristics of egg white (EW) protein (EWP) during 28 d of aerobic or anaerobic storage were explored to investigate the "self-driven" oxidation mechanism of liquid EW mediated by endogenous ROS signaling. Results revealed a significant increase in turbidity during the storage process, accompanied by protein crosslinking aggregation. The ROS yield initially increased and then decreased, leading to a substantial increase in carbonyl groups and tyrosine content. The free sulfhydryl groups and molecular flexibility in EWP exhibited synchronicity with ROS production, reflecting the self-repairing ability of cysteine residues in EWP. Fourier-transform infrared spectroscopy indicated stable crosslinking between EWP molecules in the early oxidation stage. However, continuous ROS attacks accelerated EWP degradation. Compared with the control group, the aerobic-stimulated EWP showed a significant decrease in foaming capacity from 30.5 % to 9.6 %, whereas the anaerobic-stimulated EWP maintained normal levels. The emulsification performance exhibited an increasing-then-decreasing trend. In conclusion, ROS acted as the predominant factor causing deterioration of liquid EW, triggering moderate oxidation that enhanced the superior foaming and emulsifying properties of EWP, and excessive oxidation diminished the functional characteristics by affecting the molecular structure.

Keywords: Functional properties; Protein oxidation; ROS.