Encapsulation of resveratrol in zein/pectin core-shell nanoparticles: Stability, bioaccessibility, and antioxidant capacity after simulated gastrointestinal digestion

Zein-pectin core/shell nanoparticles loaded with resveratrol were fabricated using a combination of the antisolvent precipitation and electrostatic deposition methods. These nanoparticles were stable to aggregation from pH 2 to 7 and had good heat stability (80 °C for 1 h). The nanoparticles were exposed to a simulated gastrointestinal tract (GIT) containing stomach and small intestine phases, and their bioaccessibility and antioxidant capacity were then measured. The bioaccessibility of the encapsulated resveratrol was higher than that of free resveratrol. Moreover, the in vitro antioxidant capacity of resveratrol was greatly enhanced when it was encapsulated inside the biopolymer nanoparticles, as shown by more potent ABTS+· radical scavenging and ferric ion reducing power. The gastrointestinal fluids collected after digestion of the encapsulated resveratrol also exhibited strong intracellular reactive oxygen species scavenging activity. Our results suggest that the biopolymer nanoparticles produced in this study may be an effective oral delivery system for resveratrol that could be used in functional foods or nutraceutical supplements.