Effects of high pressure processing on the interaction of α-lactalbumin and pelargonidin-3-glucoside

Effects of High Pressure Processing and Thermal Treatment on the Interaction between α-Lactalbumin and Pelargonium-3-Glucoside

“…As shown in Figure 1 , the fluorescence intensity of α-La was reduced with the increasing anthocyanin concentration due to the fluorescence quenching effect. Additionally, the maximum intensity wavelength at different thermal treatments changed little, indicating that the protein structures were not significantly affected by thermal treatments in the experimental conditions, and a similar result was found for HPP [ 22 ].…”

“…Fluorescence intensity and wavelength shift could provide information about tryptophan, tyrosine, and phenylalanine residues; the tryptophan residue was found to be dominant in absorbing the longest wavelength, displaying the largest extinction coefficient and being highly sensitive to the local environment [ 32 ]. The docking results obtained that the tryptophan residue in the binding site of α-La could be quenched by proton transfer from nearby anthocyanin [ 22 ]. In this experiment, the fluorescence spectra of α-La and P3G solutions subjected to different thermal treatments were recorded to examine the binding reaction.…”

“…α-Lactalbumin is a globular protein derived from milk with a strong Ca 2+ binding site and several distinct Zn 2+ binding sites, which can bind Mg 2+ , Mn 2+ , Na + , and K + as well. As a widely studied protein, α-La is a convenient tool for studying the interactions of a protein with other proteins, peptides, and low-molecular-weight phytochemicals of physiological significance [ 21 , 22 , 23 ]. Pelargonidin-3-glucoside is the component with the highest content of anthocyanin in strawberry, which contributes to its red color and antioxidant activity of strawberry [ 24 ].…”

“…Pelargonidin-3-glucoside is the component with the highest content of anthocyanin in strawberry, which contributes to its red color and antioxidant activity of strawberry [ 24 ]. Former research has reported the quenching parameters of α-La and pelargonidin-3-glucoside (P3G) under different high pressure conditions using fluorescence quenching and analyzed the protein structure and binding site via molecular dynamic simulations and molecular docking studies [ 22 ]. The results revealed that HPP increased the quenching reaction constants and the accessible fractions of α-La under the conditions of 100 MPa/pH 8.0 and 300 MPa/pH 8.0 [ 22 ].…”

“…Former research has reported the quenching parameters of α-La and pelargonidin-3-glucoside (P3G) under different high pressure conditions using fluorescence quenching and analyzed the protein structure and binding site via molecular dynamic simulations and molecular docking studies [ 22 ]. The results revealed that HPP increased the quenching reaction constants and the accessible fractions of α-La under the conditions of 100 MPa/pH 8.0 and 300 MPa/pH 8.0 [ 22 ]. However, the protein structure, size distribution, and their effects on the binding interactions under HPP were not studied.…”