title: Flavonol glycosides from Muehlenbeckia platyclada and their anti-inflammatory activity.
abstract: A new flavonol, morin-3-O-alpha-rhamnopyranoside (1), along with four known flavonols, kaempferol 3-O-alpha-rhamnopyranoside (2), kaempferol 3-O-beta-glucopyranoside (3), quercetin 3-O-alpha-rhamnopyranoside (4) and (+)-catechin (5), were isolated from the methanolic extract of Muehlenbeckia platyclada. The structures of these compounds were determined on the basis of chemical and spectroscopic evidence, as well as acid hydrolysis of the original glycoside. Isolates were evaluated for inhibition of generation of superoxide anion, and inhibition of release of neutrophil elastase. Compound 2 showed moderate inhibition of superoxide anion generation with an IC(50) value of 6.11+/-0.86 microg/ml; 1, 3 and 5 inhibited neutrophil elastase release with IC(50) values of 3.82+/-0.80, 8.61+/-1.38 and 4.37+/-0.72 microg/ml, respectively, and were 15-fold more potent than phenylmethylsulfonyl fluoride (PMSF), the positive control, in this anti-inflammatory assay.
authors.affiliation: Graduate Institute of Natural Products, College of Pharmacy, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
authors.forename: Chiao-Ting
authors.initials: CT
authors.lastname: Yen
authors.forename: Pei-Wen
authors.initials: PW
authors.lastname: Hsieh
authors.forename: Tsong-Long
authors.initials: TL
authors.lastname: Hwang
authors.forename: Yu-Hsuan
authors.initials: YH
authors.lastname: Lan
authors.forename: Fang-Rong
authors.initials: FR
authors.lastname: Chang
authors.forename: Yang-Chang
authors.initials: YC
authors.lastname: Wu
mesh_terms: D000893:Anti-Inflammatory Agents / Q000737:chemistry* / Q000494:pharmacology; D044948:Flavonols / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D006027:Glycosides / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D010936:Plant Extracts / Q000737:chemistry; D019664:Polygonaceae / Q000737:chemistry*
chemical_list: D000893:Anti-Inflammatory Agents; D044948:Flavonols; D006027:Glycosides; D010936:Plant Extracts; C539541:morin-3-O-alpha-rhamnopyranoside