title: Cyclooxygenase active bioflavonoids from Balaton tart cherry and their structure activity relationships.
abstract: Several flavonoids and isoflavonoids isolated from Balaton tart cherry were assayed for prostaglandin H endoperoxide synthase (PGHS-1) enzyme or cyclooxygenase isoform-1 (COX-1) activity. Genistein showed the highest COX-1 inhibitory activity among the isoflavonoids studied, with an IC50 value of 80 microM. Kaempferol gave the highest COX-1 inhibitory activity among the flavonoids tested, with an IC50 value of 180 microM. The structure-activity relationships of flavonoids and isoflavonoids revealed that hydroxyl groups at C4', C5 and C7 in isoflavonoids were essential for appreciable COX-1 inhibitory activity. Also, the C2-C3 double bond in flavonoids is important for COX-1 inhibitory activity. However, a hydroxyl group at the position decreased COX-1 inhibitory activity by flavonoids.
authors.affiliation: Department of Horticulture, Michigan State University, USA.
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.forename: M G
authors.initials: MG
authors.lastname: Nair
authors.forename: G M
authors.initials: GM
authors.lastname: Strasburg
authors.forename: A M
authors.initials: AM
authors.lastname: Booren
authors.forename: I
authors.initials: I
authors.lastname: Gray
authors.forename: D L
authors.initials: DL
authors.lastname: Dewitt
mesh_terms: D051545:Cyclooxygenase 1; D016861:Cyclooxygenase Inhibitors / Q000737:chemistry*; D005419:Flavonoids / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry* / Q000201:enzymology; D006801:Humans; D007527:Isoenzymes / Q000037:antagonists & inhibitors*; D008565:Membrane Proteins; D010936:Plant Extracts / Q000737:chemistry; D011451:Prostaglandin-Endoperoxide Synthases; D019685:Rosales / Q000737:chemistry* / Q000201:enzymology; D013329:Structure-Activity Relationship
chemical_list: D016861:Cyclooxygenase Inhibitors; D005419:Flavonoids; D007527:Isoenzymes; D008565:Membrane Proteins; D010936:Plant Extracts; D051545:Cyclooxygenase 1; C496511:PTGS1 protein, human; D011451:Prostaglandin-Endoperoxide Synthases