Abstract: To enhance the physicochemical stability of anthocyanins (ACN), this study developed four ACN-loaded nanocomplex delivery systems by electrostatic self-assembly using ovalbumin (OVA) as the carrier in combination with four different polysaccharides, namely chitosan (CS), carboxymethyl cellulose, arabic gum, and hyaluronic acid (HA), respectively. All prepared nanocomplexes exhibited high ACN encapsulation efficiency (58.87%–65.84%). The structural properties of the nanocomplexes were systematically characterized using transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Furthermore, their antioxidant capacity, thermal stability, storage stability, and gastrointestinal stability were evaluated. The results showed that at pH 2.0, all nanocomplexes exhibited small average particle sizes and favorable zeta potentials. The components of the nanocomplex could interact with each other through a combination of electrostatic attraction and hydrogen bonding. Under light exposure, the OVA-ACN-HA nanocomplex demonstrated the best thermal and storage stability, as well as good biocompatibility. Meanwhile, this system exhibited remarkable antioxidant activity, with its scavenging capacity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) cation radicals being 1.03–2.16 times and 1.38–1.64 times higher than that of free ACN, respectively. In a simulated gastrointestinal environment, the OVA-ACN-CS nanocomplex exhibited superior stability, showing approximately 3.81 times ACN retention rate after 4 h of digestion as compared to free ACN. Additionally, it demonstrated controlled and sustained release properties. This study provides a theoretical basis for improving the stability of ACN and the development of functional foods enriched with anthocyanins.

Key words: ovalbumin; anthocyanin; polysaccharide; nanocomplex; stability