In vitro gastrointestinal digestion fate, bioaccessibility, and antioxidant activity of anthocyanins encapsulated in zein/polysaccharide composite nanocarriers

Red cabbage is an excellent source of acylated and glycosylated anthocyanins, which are known to exhibit various potential health benefits. However, their limited stability and poor bioavailability have restricted their practical application. Here, the in vitro digestion behavior of red cabbage anthocyanins was studied, using a delivery system based on zein and pectin, chondroitin sulfate, and λ-carrageenan. Results indicated that anthocyanins-loaded zein/polysaccharide nanoparticles showed reduced surface hydrophobicity and good redispersibility in aqueous solutions. Under simulated gastrointestinal conditions, anthocyanins were progressively released, with most of the release occurring within the intestine. The nanocarriers maintained improved colloidal stability and anthocyanins' digestive stability, with retention rates reaching 63.02-70.64%. In addition, ACNs intestinal bioaccessibility was markedly increased to 49.89-66.12%, achieving intestine-targeted delivery. Furthermore, nanocarriers enhanced antioxidant properties of anthocyanins after gastrointestinal digestion, highlighting the potential of zein/polysaccharide carriers to protect and deliver anthocyanins in the gastrointestinal tract, further expanding their application as functional ingredients.