title: Flavan-3-ols isolated from some medicinal plants inhibiting COX-1 and COX-2 catalysed prostaglandin biosynthesis.
abstract: Extracts from the four plant species Atuna racemosa Raf. ssp. racemosa, Syzygium corynocarpum (A. Gray) C. Muell., Syzygium malaccense (L.) Merr. & Perry and Vantanea peruviana Macbr., traditionally used for inflammatory conditions, were fractionated using a cyclooxygenase-1 catalysed prostaglandin biosynthesis in vitro assay. The flavan-3-ol derivatives (+)-catechin, (+)-gallocatechin, 4'-O-Me-ent-gallocatechin, ouratea-catechin and ouratea-proanthocynidin A were isolated as active principles. The IC50 values ranged from 3.3 microM to 138 microM whilst indomethacin under the same test conditions had an IC50 value of 1.1 microM. The flavonol rhamnosides mearnsitrin, myricitrin and quercitrin were also isolated. When further tested for inhibitory effect on cyclooxygenase-2 catalysed prostaglandin biosynthesis, the five flavan-3-ol derivatives exhibited from equal to weaker inhibitory potencies, as compared to their cyclooxygenase-1 inhibitory effects. The flavonol rhamnosides were inactive towards both enzymes.
authors.affiliation: Department of Pharmacy, Uppsala University, Sweden.
authors.forename: Y
authors.initials: Y
authors.lastname: Noreen
authors.forename: G
authors.initials: G
authors.lastname: Serrano
authors.forename: P
authors.initials: P
authors.lastname: Perera
authors.forename: L
authors.initials: L
authors.lastname: Bohlin
mesh_terms: D000818:Animals; D002392:Catechin / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D002417:Cattle; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology*; D005260:Female; D005419:Flavonoids / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D014905:Independent State of Samoa; D007527:Isoenzymes / Q000378:metabolism*; D015394:Molecular Structure; D010920:Placenta / Q000201:enzymology; D018515:Plant Leaves; D018547:Plant Stems; D010946:Plants, Medicinal; D011247:Pregnancy; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism*; D012756:Sheep
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D005419:Flavonoids; D007527:Isoenzymes; D002392:Catechin; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases