Abstract
Exosomes are the smallest extracellular vesicles and can transport several molecules between cells. Mammalian milk is a significant source of exosomes. The aim of this study was to isolate exosomes from goat milk (GM) and cow milk (CM) to compare their properties and their capacities for loading with bioactive compounds. Exosomes were purified by differential ultracentrifugation and morphologically characterized by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Moringa oleiferachitin-binding protein (Mo-CBP(3)) conjugated with FITC was charged into the vesicles by four different active methods: (1) electroporation, (2) sonication, (3) freeze-thaw cycles, and (4) incubation at room temperature in the presence of saponin. DLS analysis showed no significant difference between the diameters of the two exosome species. All methods of protein charging were effective. The in vitro cell assay also confirmed successful endocytosis of exosomes from both species by HepG2 cells, particularly those loaded using the freeze-thaw cycle and sonication methods. Goat milk is a viable alternative for encapsulating and delivering bioactive molecules.