Construction of hollow zein-chitosan encapsulated peimine-curcumin self-assembled microparticles with enhanced stability and sustained release

ABSTRACT Peimine (P) and curcumin (CM) possess significant bioactivities but suffer from poor water solubility, low bioavailability, and limited stability. To address these challenges, P-CM self-assembled microparticles (SMPs) were prepared via non-covalent interactions and systematically characterized. The results demonstrated that optimal self-assembly reaction conditions occurred at pH 9, 25 °C, and a P:CM molar ratio of 1:1, yielding uniform nanoparticles (284 nm, PDI = 0.202) with a zeta potential of -19.77 mV. P-CM SMPs exhibited superior antioxidant activities, with ABTS, DPPH radical scavenging activity and FRAP values of 62.69%, 34.18%, and 81.02%, respectively, as well as enhanced anti-inflammatory activity compared to their individual components. To further improve stability and control release, the P-CM SMPs were encapsulated in a hollow zein-chitosan (HZ-CH) composite, achieving high encapsulation efficiency (96.0%). HZ-CH-SMPs exhibited storage stability over time and sustained-release behavior under simulated gastrointestinal conditions. This study provides a theoretical basis for designing delivery strategies integrating molecular self-assembly and protein-polysaccharide encapsulation to overcome solubility and bioavailability limitations of bioactive compounds in functional foods.