Non-covalent interactions between large yellow croaker (Pseudosciaena crocea) roe protein isolates and curcumin: Implications for enhanced curcumin delivery

This study investigated the influence of heat treatment on the interaction of large yellow croaker (Pseudosciaena crocea) roe protein isolate (pcRPI) with curcumin (Cur), and heated pcRPI (HpcRPI)-Cur and pcRPI-Cur complexes were also prepared. Fourier transform infrared spectroscopy, fluorescence spectroscopy, and surface hydrophobicity analysis indicated that pcRPI and HpcRPI bind to Cur mainly by hydrogen bonds, van der Waals interactions, and hydrophobic interactions, and compared with pcRPI, HpcRPI showed better binding effects with Cur. Molecular docking analysis also evaluated the binding site and the forces between vitellogenin, vitellogenin B and C in pcRPI and Cur. Furthermore, HpcRPI-Cur could form gels induced by glucono-δ-lactone (GDL), while pcRPI-Cur-GDL exhibited a fluid state. The HpcRPI-Cur-GDL gels showed great protective effects on Cur in the resistant gastrointestinal environment. These results indicated that heat treatment will improve the application of pcRPI as a functional material in the food field.