Inhibition of the Aggregation of Lactoferrin and (−)-Epigallocatechin Gallate in the Presence of Polyphenols, Oligosaccharides, and Collagen Peptide

Abstract

The aggregation of lactoferrin and (-)-epigallocatechin gallate (EGCG) was inhibited by polyphenols, oligosaccharides, and collagen peptide in this study. Polyphenols, oligosaccharides, or collagen peptide can effectively prevent the formation of lactoferrin-EGCG aggregates, respectively. The addition sequence of lactoferrin, polyphenols (oligosaccharides or collagen peptide) and EGCG can affect the turbidity and particle size of the ternary complexes in the buffer solution; however, it hardly affected the ζ-potential and fluorescence characteristics. With either positive or negative charge, polyphenols and collagen peptide disrupted the formation of lactoferrin-EGCG aggregate mainly through the mechanism of its competition with EGCG molecules which surrounded the lactoferrin molecule surface with weaker binding affinities, forming polyphenols or a collagen peptide-lactoferrin-EGCG ternary complex; for neutral oligosaccharides, the ternary complex was generated mainly through steric effects, accompanied by a change in the lactoferrin secondary structure induced by gallic acid, chlorogenic acid, and xylo-oligosaccharide. Polyphenols, oligosaccharides, or collagen peptide restraining the formation of lactoferrin-EGCG aggregate could be applied in the design of clear products in the food, pharmaceutical, and cosmetic industries.

Binding behaviors and structural characteristics of ternary complexes of β-lactoglobulin, curcumin, and fatty acids

“…The specic mode might be similar to the lactoferrin-EGCG aggregates, in which EGCG acted as linkage among proteins. 36 The zeta potential results indicated that all samples were negatively charged, and did not exceed absolute values of 40 mV, which is the signal of complex stabilization by electrostatic interactions. 37 Thus, the physical stabilities of the samples could not be explained by electrostatic stabilization, and this suggested that other forces, including hydrophobic interactions, Van der Waals interactions or steric overlap interactions, were involved.…”

Activity of catechins and their applications

“…Chemical modification, molecular interaction mechanisms, hydrogen bonding, and nanoparticle treatment increase efficiency Ferreira-Nunes et al 2017, Magalhães et al 2016, Cruz et al 2015, Yang et al 2015a, Chen et al 2010, Yang et al 2015b, Niu et al 2017, Klein et al 2012, Skowyra et al 2013, Arruda et al 2019 avoid heating them as much as possible. The lower the pH level, the more stable the anti-oxidant activities of green tea compounds.…”

“…Chemical modification of anthocyanin and procyanidins to more lipophilic compounds by mass spectroscopy has the advantage of increasing bioavailability in biological matrices because anti-oxidation activity increases based on the acylation of procyanidin B4 by saturated fatty acids (Cruz et al 2015). Polyphenols and collagen peptides can be applied to the design of clear products, via the formation of lactoferrin (LF)-EGCG aggregates, which are destroyed chiefly through competition mechanisms with EGCG molecules (Yang et al 2015a). The mechanism and structural properties of trivalent aggregates of LF and pectin in a multispectral analysis show that the fluorescence intensity of LF decreases while that of EGCG increases (Yang et al 2015b).…”

A Novel Dipeptidyl Peptidase IV Inhibitory Tea Peptide Improves Pancreatic β-Cell Function and Reduces α-Cell Proliferation in Streptozotocin-Induced Diabetic Mice

“…However, the separation and detection of small peptides from black tea extraction presented an analytical challenge because of the presence of phenolic compounds. Because polyphenols can bind to the peptides and form soluble complexes, or even insoluble particles [34,35], we chose SDS-PAGE, which is conveniently coupled with LC-MS/MS to purify and identify the peptides. The peptides remained aggregated at ~15 kDa, as shown in Figure 1, though they have been treated with ultrafiltration, using membranes with a molecular mass cutoff of 1 kDa.…”