Abstract: Licorice is a self-propelling plant that has many applications in pharmaceutical and food industries. Glycyrrhiza glabra is a kind of licorice whose main active constituentis a triterpenoid saponin called glycyrrhizin. If ether bound of glycyrrhizin is broken,it would loss its sweet taste and converts to glycyrrhetinic acid which is used as ananti-inflammatory agent. In order to produce glycyrrhetinic acid, glycyrrhizin without isolation is hydrolyzed in an acidic medium to release glycyrrhetinic acid. After filtration, glycyrrhetinic acid is extracted from resulting cake by ethyl acetate. The extract is then evaporated and the resulting solution is acetylated to produce glycyrrhetinic acid acetate. The ester is then purified by hexane and hydrolyzed with sodium hydroxide to produce glycyrrhetinic acid. The glycyrrhetinic acid produced in this way is dissolved in methanol and decolorized by activated carbon. Finally, water is added to solution to precipitate white glycyrrhetinic acid, which is purified by crystallization in aqueous ethanol to yield the final purified product.
Mitra Amani , Rahmat Sotudeh-Gharebagh Navid Mostoufi and Hosein A. Motahhari Kashani , 2005. Optimal Extraction of Glycyrrhetinic Acid Froml icorice Root . Journal of Food Technology, 3: 576-580.