Fabrication of novel casein/oligochitosan nanocomplexes for lutein delivery: Enhanced stability, bioavailability, and antioxidant properties

This study aimed to prepare novel nanocomplexes for delivery of lutein using transglutaminase (TGase)-type glycation of casein. The effect of glycated casein nanoparticles on the environmental stability, bioavailability, and antioxidant properties of lutein was investigated. Glycated casein nanoparticles with uniform distribution and small particle size were successfully prepared by ultrasound technology. The structure analysis revealed intermolecular interactions between lutein and glycated casein, with the complexes having a spherical and stable structure. The fabricated nanoparticles exhibited a high encapsulation efficiency (91.89%) and loading capacity (3.06%) for lutein. TGase-type glycation of casein nanoparticles contributed to the strong thermal stability, pH stability, storage stability, and salt stability. Moreover, glycated casein/lutein nanoparticles exhibited resistance to gastric digestion, rapid intestinal release rate, increased lutein bioavailability, and antioxidant activity under simulated digestion. This study provides key support for the development of glycated casein-based nanoparticles as delivery systems and reinforcing stability of hydrophilic nutraceuticals.