Anti-oxidant Constituents of the Roots and Stolons of Licorice (Glycyrrhiza glabra)

Abstract

As part of a search for new cancer chemopreventive agents, a new chalcone derivative (1), a novel group of neolignan lipid esters (2), and seven known phenolic compounds (formononetin, glabridin, hemileiocarpin, hispaglabridin B, isoliquiritigenin, 4'-O-methylglabridin, and paratocarpin B) (3-9) were isolated from the roots and stolons of licorice (Glycyrrhiza glabra). The structures of compound 1 and the individual components of isolate 2 were elucidated using various spectroscopic and chemical methods. All isolates were tested in an authentic peroxynitrite anti-oxidant assay. Of these compounds, hispaglabridin B (6), isoliquiritigenin (7), and paratocarpin B (9) were found to be the most potent anti-oxidant agents. Furthermore, isoliquiritigenin (7) was demonstrated to prevent the incidence of 1,2-dimethylhydrazine-induced colon and lung tumors in mice when administered at a dose of 300 mg/kg.

Dietary chalcones with chemopreventive and chemotherapeutic potential

“…Isobavachalcone (15), isolated from Angelica keiskei, significantly inhibited in vivo TPA-induced skin tumor promotion in mice [1]. Similar results were obtained with isoliquiritigenin (2), a phenolic constituent of licorice [20]. This compound inhibited TPA-independent tumor promotion in mice treated with DMBA and suppressed TPA-stimulated production of PGE2 in intact epidermal cells.…”

“…Licochalcone A (18) strongly inhibited phosphorylation of p65 at serine 276 leading to abrogation of its interaction with p300 and subsequent reduction in NF-jB transactivation. Later on, a similar mechanism leading to inhibition of LPS-induced NF-jB activation was also confirmed for licochalcone B (20) and licochalcone D (21) together with reduced LPS-induced production of nitric oxide (NO), TNF-a, and monocyte chemoattractant protein (MCP)-1 [40].…”

“…Isoliquiritigenin (2) with three hydroxyl groups acts as a monofunctional inducer of phase II enzymes, including GST and QR by triggering the antioxidant response element (ARE) in the promoter region of the QR gene [20,24]. Cuendet et al…”

“…Furthermore, among 9 isolates identified from Glycyrrhiza glabra, isoliquiritigenin (2) is one of the three most potent antioxidant compounds exhibiting peroxynitrite scavenging activity. It has been demonstrated that this compound inhibits nitric oxide (NO) production [20]. Similarly, 1,2-dihydroparatocarpin A (3), a prenylated chalcone isolated from extracts of roots or stolons of licorice, mediated effective antioxidant protection against peroxynitrite and nitric oxide [20,185].…”

Isolation, cloning and bioinformatics analysis of β-amyrin 11-oxidase coding sequence from licorice

“…Licorice contain one of the most important crude drugs in the world called glycyrrhizin, which constitutes up to 14% of total soluble solids content (Ibanoglu and Ibanoglu, 2000;Nassiri-asl and Hosseinzadeh, 2008;Shibata, 2000). Glycyrrhizin, an oleanane-type triterpene saponin, is about 50 times sweeter than sugar which is being used as a sweetener and flavoring additive in the food industry (Chin et al, 2007). It has a wide range of pharmacological, anti-bacterial and anti-oxidant activities (Varsha et al, 2013), hepato-protective (Chan et al, 2003;Jeong et al, 2002;Kimura et al, 2001), antiulcer (He et al, 2001), antiallergy (Park et al, 2004).…”