Physicochemical studies of sunflower oil based vitamin D nanoemulsions

Abstract

The cumulative scientific information available on the digestibility of cooking oils and their nutritive values has spurred interest in replacing synthetic oils with natural oils to encapsulate lipophilic bioactives in nanoemulsion form. Our aim was to design stable nanoemulsions that encapsulate maximum concentration of cholecalciferol (vitamin D3) into edible oil for improved stability and bioaccessibility. Among the four cooking oils tested, sunflower oil nanoemulsions formulated by a low energy method were found to be stable and highly miscible with Tween 85 and isopropanol (1:1) surfactant mixture. Mean droplet size of these nanoemulsions encapsulating 0.1–0.% (w/v) of cholecalciferol varied from 57.7 ± 1.9 to 158.13 ± 1.8 nm, and the ζ-potential maintained beyond −30 mV with entrapment efficiency ranging from 94.1% to 95.7%. Nanoemulsions were found to be stable over a period of 28 days upon storage at 4, 25, and 40 °C with no significant change in vitamin D3 content. Bioaccessibility studies using a simulated gastro-intestinal digestion model revealed release of 98% of the encapsulated vitamin D3. This method reported here to fabricate cooking oil based nanoemulsions for encapsulation of VD3 using simple formulations and inexpensive tools can have economic importance in therapeutic and food based approaches to enhance the quality of vitamin D nutrition.