Isolation and characterization of medicinal plant-based extracellular vesicles as nano delivery systems for ascorbic acid

AIM: Plant-derived extracellular vesicles (EVs) are natural nanovesicles for drug delivery. This study isolated and characterised EVs from medicinal plants as delivery vehicles. METHODS: Precipitation method was employed for the isolation and characterised using DLS, SEM, and TEM. The encapsulation efficiency (EE) and antioxidant activity of ascorbic acid (AA)-EVs were evaluated. RESULTS: The total yields of lyophilised vesicles per weight of the sample were 6.0, 8.6 and 9.2 mg/g for garlic, turmeric and ginger, respectively. Mean size of garlic-derived EVs, ginger-derived EVs, and turmeric-derived EVs were 101.0 ± 6.7, 226.4 ± 62.2 and 90.7 ± 2.5 nm, respectively. The zeta potential of the EVs was between -33.2 ± 10.9 and -28.8 ± 8.43 mV. Spherical morphology of the nanovesicles was confirmed by SEM and TEM. The EE of the EVs was between 78.1 ± 2.8% and 87.2 ± 1.4%. CONCLUSION: Overall, the antioxidant activity of AA-loaded EVs was better compared to free AA. This study provides evidence that these medicinal plants are rich sources for developing nanotherapeutics.