The Reduction in the IgE-Binding Ability of β-Lactoglobulin by Dynamic High-Pressure Microfluidization Coupled with Glycation Treatment Revealed by High-Resolution Mass Spectrometry

Abstract

Our previous study indicated that pretreatment by dynamic high-pressure microfluidization (DHPM) and glycation with galactose was a promising method for decreasing the immunoglobulin E (IgE)-binding ability of β-lactoglobulin (β-LG). In this work, the conformational alteration of β-LG subjected to DHPM and glycation treatment was investigated in relation to IgE-binding ability by orbitrap mass spectrometry. After DHPM pretreatment, lower IgE-binding ability of glycated β-LG was observed with increasing pressures. Prior to DHPM pretreatment, 11 glycated sites were identified, while the number of glycation sites was increased to 12 after pretreatment. However, there was no significant difference of the glycation sites at the pressures of 50, 100, and 200 MPa, respectively. Average degree of substitution per peptide molecule of β-LG (DSP) was investigated to assess the degree of glycation per glycation site. All of the samples pretreated by DHPM exhibited a higher glycation level than those without DHPM pretreatment. The shielding effects of epitopes owing to glycation contributed to the reduction of IgE-binding capacity. Orbitrap mass spectrometry could provide a comprehensive understanding of the nature of protein glycation.

Comparison of antigenicity and conformational changes to β-lactoglobulin following kestose glycation reaction with and without dynamic high-pressure microfluidization treatment

“…According to Chen et al (2017), DHPM treatment could improve the glycation level, by forming more glycation sites via conformational changes of the protein.…”

Morphological and structural characteristics of rice amylose by dynamic high‐pressure microfluidization modification

“…Previous studies reported that the starches with high‐amylose‐lipid complexes had less chance to swell and gelatinize than normal and waxy starch (Wang et al, ). Researchers agreed that the delay in swelling and gelatinization was due to the emulsifier complexation between amylose and lipids, which could prevent the transport of water into the granules and delay both the release of soluble components and the deformation and collapse of starch granules (Keetels, Van Vliet, Jurgens, & Walstra, ).…”

“…In order to obtain starch with beneficial properties, a number of studies into modified starch are increasing in extent year by year. Some new methods are more and more paid attention to the modification of starch, such as high‐pressure processing (HPP) (Cappa, Barbosa‐Cánovas, Lucisano, & Mariotti, ), high‐pressure homogenization (HPH) (Chen, Zeng et al, ; Le Thanh‐Blicharz, Lewandowicz, Błaszczak, & Prochaska, ), irradiation (Dar et al, ), enzymatic hydrolysis, and blending with other food materials (Alamri, Mohamed, & Hussain, ), as well as kinds of crosslinking and grafting methods for specific applications.…”

“…DHPM can generate high‐velocity impacts, high‐frequency vibrations, and intense shear, etc., which causes the formation of fine emulsions and modifies the texture of various dairy products. In recent research, DHPM, as an emerging technology, has been employed in the food industry, for example, for modifying proteins (Chen, Tu et al, ), starches (Tu et al, ), enzymes (Liu et al, ), fibers (Wan et al, ), pectin (Zhang, Xie, Lan, Gong, & Wang, ), etc. Chen et al () suggested that DHPM treatment could induce the degradation of pectin owing to the rupture of glyosidic bonds.…”

“…In recent research, DHPM, as an emerging technology, has been employed in the food industry, for example, for modifying proteins (Chen, Tu et al, ), starches (Tu et al, ), enzymes (Liu et al, ), fibers (Wan et al, ), pectin (Zhang, Xie, Lan, Gong, & Wang, ), etc. Chen et al () suggested that DHPM treatment could induce the degradation of pectin owing to the rupture of glyosidic bonds. Some literatures showed that the allergenicity of β‐lactoglobulin decreased, which was mainly due to the changes in the conformation of the protein induced by DHPM (Liu et al, ).…”