Abstract
In this experiment, the peanut protein isolate (PPI), soybean protein isolate (SPI), rice bran protein isolate (RBPI), and whey protein isolate (WPI) were modified by linking chlorogenic acid covalently and linking dextran by Maillard reaction to prepare protein-chlorogenic acid-dextran (PCD) conjugates. As for structures, conformational changes of conjugates were determined by Sodium Dodecyl Sulfate-Polyacrylamide Gel Electrophoresis (SDS-PAGE), Fourier transform infrared (FT-IR), and fluorescence measurements. The molecular weights of PCD conjugates became larger, the structure became disorder, and the amino acid residues inside the protein were exposed to the polar environment when compared to protein-chlorogenic acid (PC) and native proteins (NPs). As for properties, the interfacial tension reduced and antioxidant activity of PCD conjugates enhanced in varying degrees. Based on this, PCD conjugates were used as emulsifiers in order to investigate the properties of nanoemulsions and compared with PC conjugates and NPs. The mean droplet diameters (MDD) results showed that the nanoemulsions that were stabilized by PCD conjugates had the smallest particle sizes and exhibited uniformly dispersed spherical shapes. The storage and oxidative stabilities of PCD conjugates were also significantly improved. In comparison, nanoemulsion that was stabilized by PPI-chlorogenic acid-dextran conjugate had the smallest particle size and optimal stability among four protein stabilized nanoemulsions.
Highlights
Nowadays, the nanoemulsion-delivery system has received widespread attention on encapsulating, protecting, and releasing lipophilic active ingredients, which was mainly due to their high stability and superior protective effects on carrier nutrients when compared to conventional emulsions [1].the nanoemulsion-delivery system has great potential to act as carriers for various drugs and nutrients, and rapidly developed during the past few decades
Low molecular weight electrophoresis bands of protein-chlorogenic acid (PC) conjugates were lighter, and the protein migration rates became slower when compared with each native proteins (NPs) samples, which indicated that the interaction of protein with chlorogenic acid (CA) increased its molecular weight
This indicated that dextran interacted with the PC conjugates to form higher molecular weight conjugates, which was consistent with the results of electrophoretic analysis of lactoferrin-polyphenol-polysaccharide conjugates investigated by Liu et al [10]
Summary
The nanoemulsion-delivery system has received widespread attention on encapsulating, protecting, and releasing lipophilic active ingredients, which was mainly due to their high stability and superior protective effects on carrier nutrients when compared to conventional emulsions [1].the nanoemulsion-delivery system has great potential to act as carriers for various drugs and nutrients, and rapidly developed during the past few decades. Fan et al [8] found that the non-covalent combination of whey protein and epigallocatechin gallate (EGCG) could effectively improve the oxidative stability of the emulsions. Previous studies have shown that the reversibility of non-covalent binding between proteins and polyphenols could lead to the instability of the conjugates at food processing conditions [9]. In this case, covalent attachment of the protein to polyphenols might be considered as a better method. Research had shown that the covalent attachment of the protein to polyphenols showed greater potential in inhibiting lipid oxidation [10], which could improve the emulsion antioxidant properties and stability [11]. Ahmed et al [9] prepared covalently β-lactoglobulin-phenol conjugates, which showed better emulsification, oxidation resistance, and thermal stability than non-covalent conjugates
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
