title: Variations in lipophilic and vacuolar flavonoids among European Pulicaria species.
abstract: Four European Pulicaria species, P. odora, P. paludosa, P. sicula and P. vulgare, were analysed for their surface and vacuolar constituents for comparison with previous data obtained for P. dysenterica. Each species had a distinct flavonoid pattern with notable differences between leaf and inflorescence. 6-Hydroxyflavonols were the major lipophilic components in all of the species and tissues except in the leaves of P. paludosa and P. vulgare, where scutellarein 6-methyl ether was the main constituent. In the leaves of P. sicula a more unusual flavone, 6-hydroxyluteolin 5,6,7,3',4'-pentamethyl ether, was a major component. Pulicaria odora was distinguished by the presence of a series of methylated 6-hydroxykaempferol derivatives including a 3,5,6,7,4'-pentamethyl ether. Quercetagetin hexamethyl ether occurred in both tissues of P. sicula together with the 3,7,3,4'-tetra methyl ether and other quercetagetin derivatives, which were 5-methylated. Quercetagetin 3,7,3'-methyl ether was present in all species except P. odora. Flavonol glucuronides were characteristic vacuolar constituents of all the taxa studied. Two rare glycosides, patuletin and 6-hydroxykaempferol 6-methyl ether 7-glucuronides were identified in the inflorescence of P. odora. Pulicaria vulgaris, a rare plant of southern England, had the vacuolar flavonoid profile most similar to the other more abundant British plant, P. dysenterica.
authors.affiliation: School of Plant Sciences, Plant Science Laboratories, The University, Whiteknights, PO Box 221, Reading, Berks RG6 6AS, UK. christine.williams@reading.ac.uk
authors.forename: Christine A
authors.initials: CA
authors.lastname: Williams
authors.forename: Jeffrey B
authors.initials: JB
authors.lastname: Harborne
authors.forename: Jenny R
authors.initials: JR
authors.lastname: Greenham
authors.forename: Renée J
authors.initials: RJ
authors.lastname: Grayer
authors.forename: Geoffrey C
authors.initials: GC
authors.lastname: Kite
authors.forename: John
authors.initials: J
authors.lastname: Eagles
mesh_terms: D019659:Asteraceae / Q000737:chemistry* / Q000145:classification; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D003116:Color; D005419:Flavonoids / Q000737:chemistry* / Q000302:isolation & purification; D035264:Flowers / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D014018:Tissue Distribution
chemical_list: D005419:Flavonoids