separation of glabridin from licorice by reversed-phase high-performance liquid chromatography

초록

The main components of licorice root, glycyrrhizin and its aglycone, glycyrrhetinic acid, are clinically used in treatments of atherosclerosis, viral diseases, and allergic inflammation such as chronic hepatitis and atopic dermatitis, while minor components of licorice, which are mostly flavonoids, have some biological action supplementing the efficacy of licorice. Certain flavonoids isolated from licorice roots show effects on arachidonic acid metabolism, as well as antimicrobial, as antiviral, as antiinflammatory and also as antioxidants. The extracts of Glycyrrhiza glabra exhibited antioxidant activity and two antioxidant flavonoid compounds were isolated from it, glabrene and glabridin. Due to the function of skin whitening and antioxidizing of glabridin in licorice root, the concern to its commercialization is being increased. Therefore the schemes of the extraction and separation of glabridin by HPLC from licoricce root were systematically performed in this work. The analytical column was Chrompack Omnispher 5 C18 250×4.6 ㎜(Varian, U.S.A.). The flow rate of mobile phase was set at the 1.0 ㎖/min and the injection volume was 20 ㎕. The wavelength was fixed at 230 ㎚. 20 g of the powder of licorice root was dissolved in 100 ㎖ of the solvent of ethyl acetate. This sample was extracted by ultrasonic system for 1 hour at room temperature. That content of glabridin by ethyl acetate was measured as 1.26 g/licorice root kg. The column efficiencies and resolutions of glabridin were experimentally investigaed with mobile phase composition. The glabridin was well separated in the mobile phase composition of 50/50, acetonitrile/water (v/v) and its retention time was 20.3 min. The glabridin extracted from licorice root and collected several times was identified by LC/MS.