Botanical Profile
Glycyrrhiza glabra is a perennial species of the Fabaceae and the classic source of liquorice root. Root and stolon raw materials are characterised by the sweet-tasting triterpene-saponin complex centred on glycyrrhizin, together with flavonoid-rich accompanying fractions.
Glycyrrhiza glabra L. is a perennial herbaceous to subshrubby plant with a strong root and stolon system, imparipinnate leaves, pale-violet to bluish papilionaceous flowers and legumes. The species is native to southeastern Europe, western and central Asia and adjacent regions and is cultivated for root raw materials. Peeled or unpeeled roots and stolons are used as raw materials. The characteristic sweet, slightly scratchy and persistent taste profile is a central identity feature. Liquorice must be distinguished from other Glycyrrhiza species that may also be used regionally but have different profiles.
Phytochemistry
Liquorice root contains triterpene saponins, especially glycyrrhizin or glycyrrhizic acid and its salts, as well as flavonoids such as liquiritin, isoliquiritin, liquiritigenin and isoliquiritigenin, chalcones, coumarins, polysaccharides, sterols and other phenolic accompanying substances. Glycyrrhizin is central to the intense sweetness and to many regulatorily relevant effects. Deglycyrrhizinated liquorice fractions have a different profile from whole-root extracts. Content and composition depend on origin, species, harvest age, root part, peeling, drying and extraction solvent. For extracts, glycyrrhizin content, flavonoid profile, solvent and standardisation are decisive.
Traditional Uses
Liquorice is among the historically most important root raw materials in European, Arab-Persian, Chinese and Ayurvedic herbal traditions. The root was used as a sweetening, harmonising and aromatic component of complex preparations and also found use in confectionery, liquorice products, beverages and tobacco flavourings. In many traditions, liquorice served to balance bitter or pungent plant mixtures sensorially. Historical uses relate to defined root preparations and must be distinguished from modern health-related statements. Its strong sweetness also makes liquorice a technologically interesting raw material.
Current Research
Modern research on Glycyrrhiza glabra addresses glycyrrhizin, glycyrrhetinic acid, flavonoids, inflammation-related models, mucosal models, antiviral and antimicrobial test systems, pharmacokinetics and safety. Of particular relevance is the mineralocorticoid-like effect of glycyrrhizin metabolites, which at high intake or in sensitive individuals may contribute to increased blood pressure, potassium loss and other undesirable effects. Research distinguishes whole-root extracts, isolated glycyrrhizin fractions and deglycyrrhizinated preparations. European monographs and assessments address certain root preparations in the traditional context. Precise specification of the extract is indispensable for assessment.
Sources
- Plants of the World Online: Glycyrrhiza glabra L.; Royal Botanic Gardens, Kew.
- EMA/HMPC documents on Glycyrrhiza glabra L. and Glycyrrhiza inflata Bat., radix.
- Standard references and review articles on liquorice, glycyrrhizin and flavonoids.
Notice
The information presented in this botanical profile has been compiled to the best of our knowledge and belief from botanical, phytochemical, historical and scientific sources. It is intended solely for general professional information and initial orientation.
The content does not constitute an assurance of specific properties, effects, qualities or possible uses of products or extracts. In particular, it does not constitute a guarantee, a statement of suitability, or a statement regarding marketability, permissibility or usability in specific applications or markets.
Assessment of the suitability of a raw material or extract for a particular intended use, as well as compliance with all applicable legal and regulatory requirements, is the sole responsibility of the respective user.