Effect of ultrasonic treatment on the stability and release of selenium-containing peptide TSeMMM-encapsulated nanoparticles in vitro and in vivo

[Display omitted] •TSeMMM encapsulated in zein@T/GA nanoparticles were prepared.•Ultrasonic treatment enhanced encapsulation efficiency of zein@T/GA nanoparticles.•zein@T/GA enhanced the stability of TSeMMM during simulated digestion.•zein@T/GA modulated the reduced glutathione content in mouse tissues. Rice selenium-containing peptide TSeMMM (T) with immunomodulatory functions was isolated from selenium-enriched rice protein hydrolysates. However, its biological activity is difficult to be protected in complex digestive environments. In this study, T was encapsulated within zein and gum arabian (GA) through ultrasound treatment to improve its bioactivity and bioavailability. The zein@T/GA nanoparticles were formed using ultrasonic treatment at 360 W for 5 min with a 59.9% T-encapsulation efficiency. In vitro digestion showed that the cumulative release rate of zein@T/GA nanoparticles reached a maximum of 80.69% after 6 h. In addition, short-term animal studies revealed that the nanoparticles had an effect on the levels of tissue glutathione and improved peptides’ oral bioavailability. Conclusively, these findings suggest that the ultrasonicated polysaccharide/protein system is suitable for encapsulating active small molecular peptides. Furthermore, it provides a novel foundation for studying the bioavailability of active substances in functional foods.