18α-glycyrrhizin

18α-glycyrrhizin is an epimer of glycyrrhizic acid, a triterpenoid saponin and one of the main bioactive constituents found in licorice (Glycyrrhiza species)[2][6]. It is structurally similar to the more common 18β-glycyrrhizic acid but differs in stereochemistry at the C-18 position. While glycyrrhic acids are well known for their anti-inflammatory, antiviral, antiallergic, and hepatoprotective properties[3][5], the α-isomer (18α-glycyrrhizin) has been reported to have weaker antihepatotoxic and anti-inflammatory activities compared to its β counterpart[1][10]. The mechanism of action for glycyrrhic acids generally involves suppression of pro-inflammatory cytokines such as TNF-alpha, inhibition of NF-kB translocation into nuclei, free radical scavenging activity, and modulation of immune cell proliferation via JNK/ERK/PI3K-AKT pathways[3]. The presence of natural 18α-glycyrrhizin in licorice extracts is debated; it can be produced by epimerization from the β form under alkaline conditions but may also exist as a minor natural congener[2].

Other names

alpha-Glycyrrhizin18alpha-GlycylrrhizinIsoglycyrrhizinic acid18|A-Glycyrrhizic acid