Improvement of delivery properties of soybean 7S protein by high-pressure homogenization: In the case of curcumin

In this study, curcumin@high-pressure homogenization-soybean 7S protein/nanoparticles (CUR@HPH-7S-NPs) were prepared by an anti-solvent method. The physicochemical properties results showed at a CUR concentration of 4 mg/mL, CUR@HPH-7S-NPs had better size, encapsulation efficiency (EE), and zeta-potential values of 151.9 nm, 88.80 %, and −23.1 mV, respectively. Fourier transforms infrared (FTIR) and endogenous fluorescence spectroscopy results indicated CUR bound to HPH-7S through hydrophobic interactions, and the force between HPH-7S and CUR molecules was greater than that between untreated 7S protein and CUR. Furthermore, the pH stability results showed the size of CUR@HPH-7S-NPs was barely affected by pH away from adjacent area of the isoelectric point of 7S protein. The physical thermal stability and bio-accessibility results suggested that HPH-7S was more effective in delaying the degradation, had more physical thermal stability, and had a significant improvement in the bio-accessibility of CUR than that of untreated 7S protein. What's more, the antioxidant activity results showed at a CUR equivalent concentration of 40 μg/mL, the DPPH and ABTS radical scavenging activity of CUR@HPH-7S-NPs was 85.10 % and 96.64 %, respectively, both of which were significantly higher than that of free CUR. Finally, this study aimed to provide a theoretical basis for the delivery of other hydrophobic bioactive substances.