Preparation and characterization of bionanoemulsions for improving and modulating the antioxidant efficacy of natural phenolic antioxidant curcumin

• Bionanoemulsions for enhancing curcumin activity have been proposed.
• Curcumin solubility enhanced from 3 mM (oil) to ∼4.5 mM (surfactant) environment.
• Physicochemical measurements at 298.15, 303.15 and 308.15 K conforming dispersion and interaction extents.
• Dynamic light scattering for particle morphology and dispersion measurement.
• Surfactant engineered radical scavenging activity of ∼95%.

An attempt to augment the antioxidant ability of curcumin, a natural phenolic compound via encapsulation in nontoxic nanoemulsions, has been made. Ethanol and glycerol catalyzed curcumin encapsulated nanoemulsions using cottonseed oil with mild cationic, anionic and nonionic surfactants have been prepared. The prepared bionanoemulsions were found to possess characteristic particle diameter between 100 and 900 nm. The curcumin encased bionanoemulsions have been further screened for antioxidant efficacy with free radical 2, 2-diphenyl-1-picrylhydrazyl that enabled a radical scavenging activity of more than 90% as compared to pure curcumin. Alongside, the reduced surface tension and increased viscosity of curcumin encapsulated bionanoemulsions within 38.37–52.85 mN/m and 0.7947–1.042 mPa-s have quantitatively verified curcumin dispersion and interaction within the continuous medium, enabled via thermodynamic shift.

The figure shows canonical bar enclosing curcumin and justifying the selection of four different model surfactant systems with contrasting ionic nature.Figure optionsDownload as PowerPoint slide