title: Antioxidant bibenzyl derivatives from Notholaena nivea Desv.
abstract: Four new bibenzyl derivatives were isolated, together with other known bibenzyls, by bioassay-guided fractionation of a CHCl₃-MeOH extract of Notholaena nivea Desv. (Pteridaceae) aerial parts. The structures were elucidated by NMR, ESIMS and other spectral analyses. Their antioxidative effects towards superoxide, lipidic peroxidation and the 2,2'-azino-bis-3-ethilbenzothiazoline-6-sulfonic acid (ABTS) radical were assayed. Results showed that the compound 3,12-dihydroxy-5-methoxybibenzyl (6) is the most active compound in the ABTS free-radical scavenging test, while in the coupled oxidation of β-carotene and linoleic acid assay the compound 5,12-dihydroxy-3-methoxydibenzyl-6-carboxylic acid (1) exerted the highest activity after 1h. A superoxide anion enzymatic test was also carried out and the results were confirmed by an inhibition of xanthine oxidase activity assay. The putative protective role played by compounds 1 and 6 on the injurious effects of reactive oxygen metabolites on the intestinal epithelium, using a Caco-2 human cell line, was investigated. H₂O₂-induced alterations were prevented by preincubating the cells with compounds 1 and 6.
authors.affiliation: Dipartimento di Scienze Farmaceutiche e Biomediche, Università degli Studi di Salerno, Via Ponte Don Melillo 1, 84084 Fisciano (SA), Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Cioffi
authors.forename: Paola
authors.initials: P
authors.lastname: Montoro
authors.forename: Olga Lock
authors.initials: OL
authors.lastname: De Ugaz
authors.forename: Antonio
authors.initials: A
authors.lastname: Vassallo
authors.forename: Lorella
authors.initials: L
authors.lastname: Severino
authors.forename: Cosimo
authors.initials: C
authors.lastname: Pizza
authors.forename: Nunziatina
authors.initials: N
authors.lastname: De Tommasi
mesh_terms: D000975:Antioxidants / Q000494:pharmacology*; D009682:Magnetic Resonance Spectroscopy; D010936:Plant Extracts / Q000494:pharmacology*; D029625:Pteridaceae / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D000975:Antioxidants; D010936:Plant Extracts