One-pot solvent-free extraction and formulation of lipophilic natural products: from curcuma to dried formulations of curcumin

Abstract

A new environmentally friendly process for the efficient extraction and formulation of lipophilic bioactive compounds from plants has been successfully developed. This study describes the application of this ultrasound-assisted technique to the simultaneous encapsulation and extraction of curcumin from Curcuma longa in a medium essentially composed of water with the addition of biocompatible oil and surfactant. The resulting curcuminoid-loaded emulsion was called “extremulsion” for extract-emulsion. The composition of the extractant medium and ultrasonic parameters were studied to obtain optimal extremulsions in terms of droplet size, stability and curcumin-loading. Extremulsions comprising droplets with a diameter on the order of 100 nm were obtained with a curcumin recovery rate up to 87% compared to the conventional Soxhlet-assisted extraction in acetone. Their stability during the freeze-drying step has been studied in order to obtain a curcumin-loaded formulation easily stored and ready for use. Extremulsions did not show significant alteration in droplet size and composition after freeze-drying and rehydration.