Fabrication of caseins nanoparticles to improve the stability of cyanidin 3-O-glucoside. (1st July 2020) - Ouyang, Yongzhong
Highlights: MCs bound with C3G and formed complexes via hydrophobic interactions. Casein significantly prevented the thermal, oxidation, photo degradation and storage stability of C3G. Binding of C3G caused alterations of the secondary structures of the MCs. Abstract: The influence of encapsulation with caseins on the stability of cyanidin 3- O -glucoside (C3G) was investigated. The modified casein nanoparticles (MCs) prepared at pH 5.5 after heated at 80 °C for 30 min was applied to encapsulate C3G. The diameter of nanoparticle (MCs-C3G) was 110 ± 0.31 nm and zeta-potential was −8.83 ± 0.52 mV. The molecular weight of α-casein (32 kDa) and β-casein (25 kDa) increased along with the encapsulation of C3G. The interactions of MCs with C3G were examined at pH 6.3 by fluorescence spectroscopy and IR spectroscopy. MCs encapsulated C3G mainly via the hydrophobic interaction. The secondary structures of caseins were changed along with the combination of C3G, with a decreasing in α-helix, turn random, and coil structure, as well as increased β-sheet. In addition, the MCs-C3G interaction appeared to have a positive effect on the thermal, oxidation and photo stability of C3G.