title: Antioxidant and alpha-amylase inhibitory compounds from aerial parts of Varthemia iphionoides Boiss.
abstract: Various extracts of aerial parts of Varthemia (Varthemia iphionoides Boiss) were investigated for radical-scavenging activity, antioxidative activity, and porcine pancreas alpha-amylase inhibitory activity. The ethanol and water extracts showed a pronounced 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity, with inhibition of about 90% at a concentration of 100 microg/ml, and alpha-amylase inhibitory activity of about 70% at a concentration of 200 microg/ml by the 2-chloro-4-nitrophenyl alpha-maltotrioside (CNP-G3) degradation method. The ethanol extract was purified by column chromatography to give seven 3-methoxyflavones (1-7) and eudesmane sesquiterpene, selina-4,11(13)-dien-3-on-12-oic acid (8). The structures of these compounds were established by NMR, MS, and UV spectroscopy. Of 3-methoxyflavones, 5,7,4'-trihydroxy-3,6-dimethoxyflavone (1), 5,7,4'-trihydroxy-3,3'-dimethoxyflavone (2), and 5,4'-dihydroxy-3,7,3'-trimethoxyflavone (3,7,3'-tri-O-methyl-quercetin) (7) exhibited pronounced radical-scavenging activity. The antioxidative activity in the linoleic acid system was considerable in compounds 1, 2, and 5,4'-dihydroxy-3,6,7-trimethoxyflavone (4). Compounds 1, 2, 4, 5 (5,7,4'-trihydroxy-3-methoxyflavone), and 6 (5,4'-dihydroxy-3,7-dimethoxyflavone) showed markedly high inhibitory activity against porcine pancreas alpha-amylase. Eudesmane sesquiterpene did not show any activity.
authors.affiliation: Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University, Kagoshima, Japan.
authors.forename: Maher M
authors.initials: MM
authors.lastname: Al-Dabbas
authors.forename: Kanefumi
authors.initials: K
authors.lastname: Kitahara
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Suganuma
authors.forename: Fumio
authors.initials: F
authors.lastname: Hashimoto
authors.forename: Kenjiro
authors.initials: K
authors.lastname: Tadera
mesh_terms: D019659:Asteraceae / Q000737:chemistry*; D001713:Biphenyl Compounds / Q000737:chemistry; D002850:Chromatography, Gel; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D047309:Flavones / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D006834:Hydrazines / Q000737:chemistry; D013058:Mass Spectrometry; D019906:Nuclear Magnetic Resonance, Biomolecular; D010851:Picrates; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology; D045787:Sesquiterpenes, Eudesmane / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D013056:Spectrophotometry, Ultraviolet; D000516:alpha-Amylases / Q000037:antagonists & inhibitors* / Q000378:metabolism
chemical_list: D001713:Biphenyl Compounds; D004791:Enzyme Inhibitors; D047309:Flavones; D016166:Free Radical Scavengers; D006834:Hydrazines; D010851:Picrates; D010936:Plant Extracts; D045787:Sesquiterpenes, Eudesmane; C004931:1,1-diphenyl-2-picrylhydrazyl; D000516:alpha-Amylases