METHOD FOR PRODUCING MEDICINAL PLANT EXTRACTS

摘要

The invention relates to the production of phytochemically active extracts from plant material, in particular Petasites hybridus, containing not just lipophilic active agents but also polar or potentially polar components, for example alkaloids, such as pyrrolizidines. The extraction method is characterized in that liquid carbon dioxide in subcritical conditions is used as solvent, as it dissolves the liphohilic agents better than the polar components. Purification of the extract is thus rendered much simpler than in known methods. In this method, preferably at least one pressure-resistant extraction container (10) is used, into which liquid carbon dioxide is introduced in subcritical conditions, and from which a current of extract containing liquid carbon dioxide can be drawn off. In addition, there is at least one zone (160, 180) for treating the liquid carbon dioxide with an adsorbing agent. This zone is situated in the extraction container and/or downstream of said container in a separate pressure-resistant container (16).