Black rice anthocyanins nanoparticles based on bovine serum albumin and hyaluronic acid: Preparation, characterization, absorption and intestinal barrier function protection in Caco-2 monolayers

Black rice anthocyanins (BRA) nanoparticles (NPs) were prepared using hyaluronic acid (HA), oxidized hyaluronic acid (OHA) and bovine serum albumin (BSA) to enhance the absorption and bioactivity of anthocyanins (ACNs). Results showed that HA/OHA-BSA-BRA NPs had a spherical morphology and excellent dispensability, with hydrated radius- 500 nm, zeta potential-- 30 mV, and encapsulation efficiency-21 %. Moreover, using in vitro gastrointestinal release assay, we demonstrated that both BRA-loaded NPs exhibited effective controlled release properties of ACNs, significantly enhancing the accessibility of ACNs to the intestine. Cellular experiments showed that both two NPs had good biocompatibility and increased uptake of BRA. Furthermore, in comparison to the free BRA group, both BRA NPs groups significantly decreased the TEER value and increased the expression of tight junction proteins (Claudin 1, Occludin and ZO-1) in Caco-2 cell monolayers with LPSinduced damage. Therefore, our study demonstrated that HA/OHA-BSA-BRA NPs are promising carriers of ACNs and can effectively prevent the LPS-induced intestinal barrier injury in vitro.