Formulation of virgin coconut oil microemulsion with natural excipients

Abstract

Introduction: Virgin coconut (Cocos nucifera (L.)) oil (VCO) is taking attention from re-searchers because of its biological activities. However, applying VCO directly on the skin often leaves an uncomfortable feeling of greasy, clogged pores and difficult to wash. Coco-nut oil in microemulsion is a better option since it can increase bioavailability as well as convenience for users. Furthermore, this study aims to use natural ingredients, safe for the skin and environmentally friendly. Methods: The research started from extracting saponins from Gleditsia australis by using ethanol and water as extraction solvents. The extracted saponins were characterized by chemical reactions. Then we combined saponins and some other surfactants to investigate the possibility of microemulsion formation. Results: We extracted saponins with efficiency of 7.2%. The results showed that microemul-sions were formed using a mixture of surfactants including saponins and lecithin (ratio of 0.05:100 w:w) in the formula with a ratio of water phase, oil phase, surfactants respectively 3%, 48.5%, 48.5%. Microemulsion met the requirements of quality control and the product is microbiologically stable after 3 months of storage without using preservatives. Conclusion: In this study, we have successfully prepared Virgin coconut oil microemulsion using natural excipients including Virgin coconut oil, water and a mixture of surfactants used as saponins and lecithin. The system showed stability at 30 and 40 °C upon three-month storage and the product is microbiologically stable after 3 months of storage without using preservatives.