Glycyrrhizin (Saponin)

Glycyrrhizin is a triterpenoid saponin (oleanane-type) and the primary bioactive compound of licorice root (Glycyrrhiza glabra/uralensis), not a whole food ingredient, so traditional macronutrient/micronutrient framing does not apply. Key compositional data: Glycyrrhizin (glycyrrhizic acid) constitutes approximately 2–25% dry weight of licorice root, with commercial extracts standardized to 20–25% glycyrrhizin content. Molecular weight: 822.94 g/mol (ammonium glycyrrhizinate form). Structurally, it is a glycoside consisting of one molecule of 18β-glycyrrhetinic acid (the aglycone) linked to two glucuronic acid residues, which govern its amphiphilic and surfactant (saponin) properties. Bioavailability: Orally ingested glycyrrhizin is poorly absorbed intact in the small intestine; gut microbiota (Eubacterium sp., Ruminococcus sp.) hydrolyze it to 18β-glycyrrhetinic acid, the primary systemically active metabolite, with peak plasma levels reached at approximately 8–24 hours post-ingestion. Bioavailability of intact glycyrrhizin is estimated at <1% orally; 18β-glycyrrhetinic acid bioavailability is substantially higher (~40% relative). Intravenous formulations (e.g., Stronger Neo-Minophagen C used clinically in Japan) bypass gut metabolism entirely. Typical research doses: 75–760 mg/day glycyrrhizin equivalent in clinical contexts. Co-occurring compounds in licorice-sourced preparations include liquiritin (~0.5–5% dry weight), isoliquiritigenin, glabridin, and licochalcone A, which may contribute synergistic bioactivity but are distinct from glycyrrhizin itself. No significant macronutrient, vitamin, or mineral contribution is attributable to isolated glycyrrhizin at pharmacological doses.