Cellulose nanocrystal (CNC)-stabilized Pickering emulsion for improved curcumin storage stability

Curcumin is a bioactive supplement known to have many medical benefits. However, it has low bioavailability due to its insolubility in aqueous solution and rapid degradation profile. In this paper, an oil-in-water (O/W) Pickering emulsion (PE) was fabricated ultrasonically with different cellulose nanocrystal (CNC) concentrations to investigate its effect on the physicochemical properties of PE and the storage stability of curcumin. The CNC-PE produced remained stable for at least one month. The highest encapsulation efficiency of curcumin in CNC-PE was found to exceed 99%. For storage of curcumin containing CNC-PE under dark conditions, good stability of curcumin was observed with a half-life of 98.47 d, reflecting a nearly 20-fold improvement as compared to other existing PE systems. On the other hand, storage under visible light, UV light, and at elevated temperature (50 °C) increased the degradation rate of encapsulated curcumin following the order: 50 °C > UV light > visible light > dark. Our findings elucidated the promising potential of CNC-PE as a food-safe delivery system for sensitive lipophilic bioactive compounds.