Preparation of Casein Biopeptide-Loaded Niosomes by High Shear Homogenization and Their Characterization

The aim of this study was to develop a niosomal system to deliver milk bioactive peptides with potential for enhanced bioavailability. Milk casein was hydrolyzed with Flavourzyme, and the hydrolysates were ultrafiltered to obtain low-molecular-weight peptides with enhanced antioxidant activity. Biopeptide-loaded niosomes were prepared by a high shear homogenization method. Peptide-loaded niosomes exhibited a mean particle size of 37.64 ± 0.98 nm with narrow size distribution (PDI = 24.66 ± 0.008%) and high zeta potential (-23.36 mV). The niosomes encapsulated about 67% of peptides into the vesicles and showed controlled and sustained release under simulated gastrointestinal conditions as compared to free peptides. The antioxidant activity of the peptides was not affected due to their encapsulation into niosomes. Morphology of peptide-loaded niosomes was determined by scanning electron microscopy, transmission electron microscopy and atomic force microscopy, and the microstructural interactions analyzed by Fourier transform infrared clearly indicated the formation of peptide-loaded niosomes. High-performance liquid chromatography spectra of peptides in the niosomes and the free peptides were similar, thus confirming their entrapment into the niosomes.