Jaboticaba (Plinia peruviana) extract nanoemulsions: development, stability, and in vitro antioxidant activity.

OBJECTIVE

The aim of this work is to develop and characterize nanoemulsions containing jaboticaba extract (Plinia peruviana) aiming pharmaceutical and cosmetic applications.

METHODS

Nanoemulsions were prepared by high-pressure homogenization method using different concentrations of components (oil, surfactant, and extract) and homogenization pressures, in order to optimize the preparation conditions. Both unloaded and extract-loaded nanoemulsions were characterized according to their size, polydispersity, zeta potential, pH, morphology, and physical stability. Total phenolic and flavonoid contents in free jaboticaba extract and jaboticaba-loaded nanoemulsions were determined spectrophotometrically, while ellagic acid content was determined by high-performance liquid chromatography (HPLC) analysis. In vitro antioxidant activity was investigated by 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) methods.

RESULTS

Colloidal dispersions exhibited a mean particle size around 200 nm, with monodisperse size distribution (PdI <0.3), and spherical shape. Stability studies showed that nanoemulsions were stable over 120 d of storage at room temperature. Jaboticaba nanoemulsions showed significant concentrations of phenolics, flavonoids, and ellagic acid, with encapsulation efficiency values higher than 90%. Antioxidant properties of jaboticaba nanoemulsions were demonstrated by its remarkable ability to scavenge DPPH free radicals and to reduce ferric-tripyridyltriazine complex, which can be attributed to their phenolic and flavonoid contents.

CONCLUSIONS

The results suggest that nanoemulsions containing jaboticaba extract can be considered a promising candidate as a new antioxidant agent.