SUPERCRITICAL-FLUID EXTRACTION OF COMPOUNDS FROM PLANT-ORIGIN

Supercritical fluid extraction of compounds from plant origin. Supercritical fluid extraction (SFE) characteristics are particularly interesting in the extraction of compounds from plant origin: extractions are fast and can be performed at low temperatures on-line coupling with chromatographic methods is possible, etc. As the solvent strength of supercritical fluids is proportional to their density, a selective extraction can be obtained using a pressure or temperature gradient. The addition of polar modifiers allows to enhance the solvent strength of supercritical fluids with a view to extract moderately polar compounds. On-line coupling with a chromatographic method facilitates the analysis of extracted substances whose concentration in plants is often low. Various applications of SFE to the extraction of natnral products are given.