Preparation of W/O/W Pickering emulsion based on ursolic acid

Abstract

Objective: This study aimed to improve the application range and bioavailability of ursolic acid. Methods: The W/O/W pickering emulsion was prepared by a two-step process with ursolic acid as emulsifier and pectin as external aqueous phase. The preparation conditions of W/O emulsion were optimized by a single factor experiment, and the effects of pectin mass concentration on physicochemical properties, microstructure, rheological properties and long-term stability of W/O/W pickering emulsion were studied. Results: The optimal preparation technology of W/O emulsion was ursolic acid mass concentration of 4 g/100 mL, water-oil mass ratio of 2∶3, homogenization speed of 9 000 r/min, homogenization time of 5 min. The particle size of the double emulsion prepared with pectin as the external aqueous phase was between 30～40 μm. The absolute value of zeta potential, rheological property and storage stability of the emulsion at 4 ℃ were significantly improved with the increase of pectin mass concentration. Conclusion: The stable pickering double emulsion could be prepared when the mass concentration of pectin was 0.3, 0.4, 0.5 g/100 mL.

Keywords

• w/o/w
• pickering emulsion
• ursolic acid
• pectin
• stability