title: Antioxidant and anti-inflammatory activities of six flavonoids separated from licorice.
abstract: Licorice, the roots and rhizomes of several Glycyrrhiza species (Leguminosae), is an important natural sweetening agent and a widely used herbal medicine. In this work, six flavonoids, 5-(1,1-dimethylallyl)-3,4,4'-trihydroxy-2-methoxychalcone (1), licochalcone B (2), licochalcone A (3), echinatin (4), glycycoumarin (5) and glyurallin B (6), were isolated from the extracts of licorice (Glycyrrhiza inflata and Glycyrrhiza uralensis). Their structures were elucidated using various spectroscopic methods. To our knowledge, compound 1 was isolated from natural plants for the first time. All the isolates were tested by antioxidant and anti-inflammatory assays. Compounds 2, 4 and 5 showed strong scavenging activity toward the ABTS(+) radical, and compounds 1, 2, 3, 5 and 6 exhibited potent inhibition of lipid peroxidation in rat liver microsomes compared with the reference controls. Compounds 1-4 dose-dependently inhibited LPS induced reactive oxygen species (ROS) production in RAW 264.7 cells. Furthermore, compounds 1-5 were demonstrated to inhibit the production of nitric oxide (NO), interleukin-6 (IL-6) and prostaglandin E2 (PGE2) in LPS-induced macrophage cells. Moreover, the contents of the six compounds, in different Glycyrrhiza species, were quantified by HPLC-MS.
authors.affiliation: State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Fu
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Yan-Jing
authors.initials: YJ
authors.lastname: Li
authors.forename: Yun-Feng
authors.initials: YF
authors.lastname: Zheng
authors.forename: Ping
authors.initials: P
authors.lastname: Li
mesh_terms: D000818:Animals; D000893:Anti-Inflammatory Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D000975:Antioxidants / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D015232:Dinoprostone / Q000378:metabolism; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D006035:Glycyrrhiza / Q000737:chemistry*; D015850:Interleukin-6 / Q000235:genetics / Q000276:immunology; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D051379:Mice; D008862:Microsomes, Liver / Q000187:drug effects / Q000378:metabolism; D009569:Nitric Oxide / Q000276:immunology; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats
chemical_list: D000893:Anti-Inflammatory Agents; D000975:Antioxidants; D005419:Flavonoids; D015850:Interleukin-6; D010936:Plant Extracts; D009569:Nitric Oxide; D015232:Dinoprostone