Variation in the structure and emulsification of egg yolk high‐density lipoprotein by lipid peroxide

November 13, 2019

Title

Variation in the structure and emulsification of egg yolk high‐density lipoprotein by lipid peroxide

Author

Zhijie Bao, Da Kang, Xiaomeng Xu, Na Sun, Songyi Lin

Year

2019

Journal

Journal of Food Biochemistry

Abstract

To further clarify the effect of the oxidation of egg yolk high‐density lipoprotein (EYHDL) on the protein structure and emulsification, 2,2′‐azobis (2‐methylpropionamidine) dihydrochloride (AAPH) was selected as a representative lipid peroxidation‐derived peroxyl radical. The results of Raman spectroscopy indicated that, with the increase in the concentration of AAPH, the EYHDL carbonyl content increased significantly and the free sulfhydryl content declined sharply. Circular dichroism spectroscopy and intrinsic fluorescence indicated that exposure of EYHDL to AAPH led to destruction of the orderly structure and reduction of the structural stability. The particle size distribution and zeta potential indicated that the peroxyl radical caused molecular aggregation. Moderate oxidizing conditions can enhance the emulsification of EYHDL, and high‐intensity oxidation decreased emulsification. The research results indicated that EYHDL made a significant change in the oxidation system and led to a change in its structure and emulsification, providing a theoretical basis to clarify the EYHDL oxidation mechanism.

Instrument

J-1500

Keywords

Circular dichroism, Chemical stability, Secondary structure, Protein folding, Food science, Biochemistry