Coordinated encapsulation by β-cyclodextrin and chitosan derivatives improves the stability of anthocyanins

To improve the stability of anthocyanins (ACNs), ACNs were loaded into dual-encapsulated nanocomposite particles by self-assembly using & beta;-cyclodextrin (& beta;-CD) and two different water-soluble chitosan derivatives, namely, chitosan hydrochloride (CHC) and carboxymethyl chitosan (CMC). The ACN-loaded & beta;-CD-CHC/CMC nanocomplexes with small diameters (333.86 nm) and had a desirable zeta potential (+45.97 mV). Transmission electron microscopy (TEM) showed that the ACN-loaded & beta;-CD-CHC/CMC nanocomplexes had a spherical structure. Fourier-transform infrared spectroscopy (FT-IR), nuclear magnetic resonance (1H NMR) and X-ray diffraction (XRD) confirmed that the ACNs in the dual nanocomplexes were encapsulated in the cavity of the & beta;-CD and that the CHC/CMC covered the outer layer of & beta;-CD through noncovalent hydrogen bonding. The ACNs from the dual-encapsulated nanocomplexes improved stability of ACNs under adverse environmental conditions or in a simulated gastrointestinal environment. Further, the nanocomplexes exhibited good storage stability and thermal stability over a wide pH range when added into simulated electrolyte drinks (pH = 3.5) and milk tea (pH = 6.8). This study provides a new option for the preparation of stable ACNs nanocomplexes and expands the applications for ACNs in functional foods.

Automated summary

To improve the stability of anthocyanins (ACNs), researchers loaded ACNs into dual-encapsulated nanocomposite particles using β-cyclodextrin (β-CD) and water-soluble chitosan derivatives (chitosan hydrochloride and carboxymethyl chitosan). The ACN-loaded β-CD-chitosan hydrochloride/carboxymethyl chitosan (CHC/CMC) nanocomplexes showed spherical structure and improved ACNs stability under adverse environmental conditions or in a simulated gastrointestinal environment. This study provides a new option for the preparation of stable ACNs nanocomplexes and expands the applications for ACNs in functional foods.