Synthesis, structural characterization, and evaluation of cyanidin-3-O-glucoside-loaded chitosan nanoparticles

Crabapple (Malus prunifolia Willd. Borkh) is a kind of wild apples with many health benefits. However, the utilization of crabapple fruit remains scarce, due to the poor stability of C3G. In this study, C3G loaded nanoparticles were established by chitosan (CS), chitosan oligosaccharides (CSO), and carboxymethyl chitosan (CMC) united with ionic crosslinking agent γ-Polyglutamic acid (PGA) or calcium chloride (CaCl₂) to improve the stability of C3G. Results showed that C3G-loaded nanoparticles were exhibited nearly spherical with homogeneous morphology. Particularly, C3G-CMC-CaCl₂ nanoparticles exhibited the highest encapsulation efficiency (53.88%) and loading efficiency (5.11%) with preferable particle size (180 nm), good stability (-19 mV) and blood compatibility. C3G-CMC-CaCl₂ nanoparticles also revealed the highest releasing ratio (~75%) at pH 5.3 with stability. Present study established the chemical and cell biological basis for further application of C3G-loaded nanoparticles in nutraceutical and functional food fields, extending the application of crabapple in food processing with bioactive enhancement.