Separation and analysis of glycyrrhizin, 18β-glycyrrhetic acid and 18α-glycyrrhetic acid in liquorice roots by means of capillary zone electrophoresis

Abstract

Glycyrrhizin is the main active compound of Glycyrrhiza glabra root extracts; according to recent studies, glycyrrhizin and its aglycon, glycyrrhetic acid, have interesting therapeutic properties. A new capillary electrophoretic method has been developed for the separation and quantification of glycyrrhizin, beta-glycyrrhetic acid and its isomer a-glycyrrhetic acid. Separation of the analytes was achieved in less than 3 min on a fused silica capillary, by injecting the samples at the short end of the capillary (effective length: 8.5 cm). The background electrolyte was composed of pH 10.0 carbonate buffer, methanol and ethylene glycol (80/10/10) and contained 0.4% beta-cyclodextrin; indomethacin was used as the internal standard. Diode array detection was used, with quantitative assays carried out at 254 nm. Linearity was found over the 5-200 and 2.5-100 microg mL(-1) concentration ranges for glycyrrhizin and glycyrrhetic acid, respectively. This method has been applied to the determination of the analytes in different matrices (liquorice roots and commercial confectionery products), and to the purity control of beta-glycyrrhetic acid obtained from the hydrolysis of glycyrrhizin. When analysing beta-glycyrrhetic acid and its epimer in roots, the samples were purified by means of a suitable solid-phase extraction (SPE) procedure with Oasis HLB cartridges, which granted good selectivity, eliminating matrix interference.

A novel process for extraction of natural sweetener from licorice (Glycyrrhiza glabra) roots

“…So the nature of organic extractant and pH are the crucial factors for purification of GA. Several procedures are reported in the literature on solvent extraction [5] Preparative purification of glycyrrhizin extracted from the root of licorice using high-speed counter-current chromatography Jiang et al 2004 Powder of licorice roots is extracted by 70% aqueous-methanol solution, then filtered and HCl is added for precipitation. Precipitation is dried by freeze-drying and separation of components is carried out by HSCCC [6] Separation and analysis of glycyrrhizin, 18␤-glycyrrhetic acid and 18␤-glycyrrhetic acid in licorice roots by means of capillary zone electrophoresis Sabbioni et al…”

“…Most accepted technologies of the extraction of GA from the roots include extraction with hot water at ambient pressure in the presence of various additives like alkalis, mineral acids, ethyl alcohol, etc., such as, aqueous ammonia [2][3][4], methanol [5][6][7], ethanol [8]. The primary aqueous extract of licorice roots contains GA and many other water-soluble substances and then it is subjected to further processing for more purified products.…”

Solid‐phase extraction of liquiritin and glycyrrhizic acid from licorice using ionic liquid‐based silica sorbent

“…It is a Chinese herb that is commonly used as an expectorant and to arrest coughing, reduce fever, comfort the stomach, alleviate urgency and potentiate the effects of various other herbs [2,3]. Liquiritin (LQ) (Fig.…”

Changes in Components, Glycyrrhizin and Glycyrrhetinic Acid, in RawGlycyrrhiza uralensisFisch, Modify Insulin Sensitizing and Insulinotropic Actions

“…The 18-and 18-isoforms of glycyrrhetinic acid were not separated in HPLC analysis. Since these epimers have been reported to have similar biological activities 14,15) and they had comparable insulin-stimulated glucose uptake in our preliminary experiment, we used a racemic mixture of 18-and 18-glycyrrhetinic acid (1:1) as a reference for further experiments. The mixture was abbreviated as glycyrrhetinic acid.…”