Saponins from European Licorice Roots (Glycyrrhiza glabra)

Abstract

European licorice roots ( Glycyrrhiza glabra), used in the food and beverage industry due to their distinctive sweet and typical licorice flavor, were fractionated, with the triterpenoid saponins isolated and their chemical structures determined by means of ESIMS, ESIMS/MS, HRESIMS, and 1D/2D NMR experiments. Next to the quantitatively predominant saponin glycyrrhizin (11) and some previously known saponins, the structures of 10 monodesmosidic saponins were assigned unequivocally for the first time, namely, 30-hydroxyglycyrrhizin (1), glycyrrhizin-20-methanoate (2), 24-hydroxyglucoglycyrrhizin (3), rhaoglycyrrhizin (4), 11-deoxorhaoglycyrrhizin (5), rhaoglucoglycyrrhizin (6), rhaogalactoglycyrrhizin (7), 11-deoxo-20α-glycyrrhizin (8), 20α-galacturonoylglycyrrhizin (9), and 20α-rhaoglycyrrhizin (10).

Review of Constituents and Biological Activities of Triterpene Saponins from Glycyrrhizae Radix et Rhizoma and Its Solubilization Characteristics

“…In addition, similar triterpene saponins, such as licorice-saponin G2 (9) and araboglycyrrhizin (16), were also observed in G. uralensis, G. glabra, and G. inflate. Eleven triterpene saponins (2, 4, 5, 10-12, 14, 25, 26, 36, and 41) were also found both in G. uralensis and G. glabra, including uralsaponin B (2) [16,21], licorice-saponin B2 (4) [22,23], licorice-saponin C2 (5) [22,23], licorice-saponin H2 (10) [23,24], licorice-saponin J2 (11) [23,24], licorice-saponin K2 (12) [21,24], 18α-glycyrrhizic acid (14) [17], licorice-saponin M3 or uralsaponin T (25) [27,31], licorice-saponin N4 (26) [31,32], uralsaponin V (36) [21,27], and 3-O-β-d-glucuronopyranosylglycyrrhetinic acid (41) [21,27].…”

Natural Product Triterpenoids and Their Semi-Synthetic Derivatives with Potential Anticancer Activity

“…The sweet-tasting oleanane-type triterpene glycoside glycyrrhizin (8) (▶ Fig. 2) is used as an ingredient in the food and beverage industry and is the major active constituent of Glycyrrhiza glabra L. (licorice) (Fabaceae) [45]. This and 2 other Glycyrrhiza species are official sources of licorice in the Chinese Pharmacopoeia, with G. glabra demonstrated as having anti-inflammatory, antioxidant, antiviral, hepatotoxic, and neuroprotective propensities [46].…”

Investigations into the Structure-Function Relationship of the Naturally-Derived Surfactant Glycyrrhizin: Emulsion Stability

“…To ensure no effect from ammonia, we purified the substance by solubilizing 50 g of glycyrrhizin ammoniacal in 3 L of purified water and used formic acid (2.2•10 −3 mol L −1 , corresponds to 1%) to reduce the pH to 3. The solution was freeze-dried and the process was [10] repeated to make sure that no ammonia was present. A quantitative nuclear magnetic resonance spectroscopy (qNMR) as reported by Frank, Kreissl, Daschner, and Hoffman [15] was applied to determine the purities of glycyrrhizin and 18ßglycyrrhizinic acid.…”