[Efficiency of supercritical fluid extraction for the production of non-volatile terpenoids from Taraxaci radix].Acta Pharm Hung. 2001 Oct; 71(3):318-24.AP
Supercritical fluid extraction (SFE) is an extraction technique which exploits the solvent properties of fluids above their critical point. As a result supercritical fluid extraction was used to gain various active substances from plants. The use of SFE to obtain bioactive substances from medicinal plants over the past twenty years has been proved to be a viable alternative for the extraction of natural compounds. Dandelion (Taraxacum officinale Wiggers et Webers, Asteraceae) is one of the best known European medicinal plants, not only as a traditional medicine but perspective raw material for modern phytopharmaceuticals. From the characteristic principles our attention has been directed to triterpenes and phytosterols with anti-inflammatory activity, which were extracted with supercritical carbon dioxide. Designed experiments were carried out to determine the optimal extraction parameters. The products obtained by supercritical fluids extraction were compared to extracts prepared by traditional extraction method (Soxhlet) with n-hexane and ethyl alcohol solvents. The content of triterpenes and sterols was monitored after saponification by thin layer chromatography-densitometry. The products gained by supercritical fluid extraction were different from the traditional ones both in their appearance and composition. Triterpenes and their esters were extracted quantitatively by supercritical fluid extraction using CO2 as solvent and the extraction dynamic for triterpenes and phytosterols was different. Triterpenes had a higher concentration in the SFE product then in the extracts prepared by traditional methods.