Licorice Root (Glycyrrhiza glabra)

Licorice root (Glycyrrhiza glabra) is a perennial legume native to Eurasia. Its rhizome has been used for millennia as a flavoring agent and traditional medicine. The dried root contains a complex mixture of saponins, flavonoids, and polysaccharides. These compounds give it anti-inflammatory, antiviral, and endocrine-modulating properties, making it a popular botanical supplement for digestive, respiratory, and metabolic support.

• Glycyrrhizin (glycyrrhizic acid): C₄₂H₆₂O₁₆, MW = 822.94 g/mol. IUPAC: (4S,5S,6R,7R,8R,9S,10S,11R,12S,13R,14S,15R,16S,17S)-4-(β-D-glucopyranosyl-β-D-glucopyranosyl-oxy-) -5-(hydroxy)-6-(hydroxymethyl)-7-(hydroxymethyl)-8-(hydroxymethyl)-9-(hydroxymethyl)-10-(hydroxy)-11-(hydroxymethyl)-12-(hydroxymethyl)-13-(hydroxy)-14-(hydroxymethyl)-15-(hydroxymethyl)-16-(hydroxymethyl)-17-(hydroxy)-1-(3-hydroxy-2-methyl-prop-2-enyl)-1-(hydroxymethyl)-1-(hydroxy)-1-(hydroxy)-1-(hydroxy)-1-(hydroxy)-1-(hydroxy)-1-hydroxy-1-hydroxy-1-hydroxy-1-hydroxy-1-hydroxy-1-hydroxy-1-hydroxy-1-hydroxy-1-hydroxy-1-hydroxy).
• Key structural features: A triterpenoid (β-amyrin) skeleton with a glucuronic acid disaccharide (glycone) at C-3, conferring high water solubility and the ability to bind mineralocorticoid receptors. Additional flavonoids (liquiritigenin, isoliquiritigenin) contain phenyl-propane-type structures facilitating antioxidant activity.

• Cultivation: Licorice root is cultivated commercially in Turkey, China, and Iran, where the plant thrives in temperate, well-drained soils.
• Wild Harvesting: Wild-harvested roots from the Balkans are also used.
• Extraction: Extraction typically employs 70 % ethanol or water-ethanol mixtures to solubilize glycyrrhizin and flavonoids, followed by spray-drying to produce powdered extracts.
• DGL Production: DGL is produced by enzymatic hydrolysis of glycyrrhizin to glycyrrhetic acid, reducing mineralocorticoid activity.
• Quality Considerations:
  • Glycyrrhizin content (10–20 % for standard extracts, ≤ 0.2 % for DGL).
  • Absence of heavy metals and pesticide residues (verified by USP or ISO 17025-certified laboratories).
  • Content of marker flavonoids (≥ 0.2 % liquiritin).
• Manufacturing Standards: Good Manufacturing Practice (GMP) and third-party testing ensure batch-to-batch consistency for supplements.