Influence of the maturity on the characteristics of orange-derived extracellular vesicles and their delivery performance for curcumin

Plant-derived extracellular vesicles have considerable potential as natural pharmaceutical and nutraceutical delivery systems. However, the impact of plant maturity on the physicochemical and structural properties of isolated extracellular vesicles is currently unknown. In this work, extracellular vesicles isolated from oranges at different maturity stages were first characterized and compared. Afterwards, polyphenol-load orange juices were successfully prepared by incorporating polyphenols (mainly curcumin) into extracellular vesicles originated from orange juices. Encapsulation in vesicles was found to increase the solubility, stability, bioaccessibility, and antioxidant activity of curcumin, but the effects depended on the maturity of oranges. Specifically, the vesicles from unripe and ripe orange juices were more effective for curcumin delivery than those from overripe orange juice. Conclusively, this study has provided important new information about the optimum maturity for isolating fruit-derived extracellular vesicles. Moreover, the extracellular vesicle-based delivery systems developed in this study may facilitate the design of more effective functional foods and beverages.