Fabrication and characterization of zein-sodium alginate complex nanoparticles as an effective naringenin delivery system: Physicochemical stability, solubility, antioxidant activity

Naringenin (NAR) is a native polyphenolic compound that has a variety of physiological benefits. However, the application of NAR in functional food fields is limited due to its high hydrophobicity and insufficient oral bioavailability. The objective of this study is to prepare naringenin-encapsulated zein-sodium alginate nanoparticles (NAR-Z/SA NPs) to improve the antioxidant effects of NAR by increasing the water solubility. The spherical NAR-Z/SA NPs possessed increased encapsulation efficiency (83.92 ± 0.32%) and loading capacity (18.24 ± 0.73%). The X-ray diffraction and differential scanning calorimetry results confirmed that NAR was in an amorphous state after being encapsulated. Fourier transform infrared spectroscopy revealed that hydrogen bonding, electrostatic interaction, and hydrophobic interaction drove the formation of the NAR-Z/SA NPs. Meanwhile, NAR-Z/SA NPs exhibited desirable pH (3.0–8.0), ionic (0–50 mM) and heating treatment (80°C) stability. Furthermore, NAR-Z/SA NPs had improved solubility and antioxidant activity compared with free NAR. In addition, the NAR-Z/SA NPs showed sustained release of NAR under simulated gastrointestinal conditions. These findings provide an effective choice for the broad application of NAR in food industries.