title: Antioxidant, alpha-amylase inhibitory and brine-shrimp toxicity studies on Centaurea centaurium L. methanolic root extract.
abstract: Free radical scavenging activity of the methanolic extract of the roots of Centaurea centaurium L. (Asteraceae) and its phenolic, non-polar and water fractions was measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The phenolic fraction showed high radical-scavenging activity with DPPH (IC(50) of 57 microg mL(-1)) and potent antioxidant properties both on lipid peroxidation and beta-carotene bleaching (IC(50) of 195 and 5 microg mL(-1), respectively). The n-hexane fraction of the extract showed the highest inhibitory activity against alpha-amylase with an IC(50) of 158 microg mL(-1). In this fraction, the most abundant constituents were the fatty acids: 11,14-eicosadienoic acid methyl ester, 9-octadecenoic acid methyl ester and 9-octadecenoic acid. Various terpenes, e.g. cypirene, alpha-zingiberene, beta-farnesene, beta-santalene, beta-bisabolene, beta-himachalene and azulene were also present. The LC(50) against the brine shrimp nauplii for the methanolic extract was found to be 44.05 microg mL(-1), whilst LC(50) values for the polyphenolic, lipophilic and water fractions were found to be 157.44, 25.98 and 152.81 microg mL(-1), respectively.
authors.affiliation: Department of Pharmaceutical Science, University of Calabria, Rende, CS, Italy. filomena.conforti@unical.it
authors.forename: Filomena
authors.initials: F
authors.lastname: Conforti
authors.forename: Federica
authors.initials: F
authors.lastname: Menichini
authors.forename: Monica R
authors.initials: MR
authors.lastname: Loizzo
authors.forename: A Giancarlo
authors.initials: AG
authors.lastname: Statti
authors.forename: Antonio
authors.initials: A
authors.lastname: Rapisarda
authors.forename: Francesco
authors.initials: F
authors.lastname: Menichini
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Houghton
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry / Q000494:pharmacology; D001156:Artemia / Q000187:drug effects*; D001713:Biphenyl Compounds / Q000494:pharmacology; D031179:Centaurea / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology*; D006834:Hydrazines / Q000494:pharmacology; D015227:Lipid Peroxidation / Q000187:drug effects; D010851:Picrates; D018517:Plant Roots / Q000737:chemistry; D010946:Plants, Medicinal / Q000737:chemistry*; D000516:alpha-Amylases / Q000037:antagonists & inhibitors*; D019207:beta Carotene / Q000378:metabolism
chemical_list: D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D006834:Hydrazines; D010851:Picrates; D019207:beta Carotene; C004931:1,1-diphenyl-2-picrylhydrazyl; D000516:alpha-Amylases