title: Antioxidant and antimutagenic properties of Hibiscus tiliaceus L. methanolic extract.
abstract: The genus Hibiscus thrives in a variety of climates and produces a diversity of natural compounds with bioactive properties. We have studied the chemical composition and the in vivo antioxidant properties of Hibiscus tiliaceus L. methanolic flower extract, as well as its mutagenic/antimutagenic effects. Vitamin E and some stigmasterol derivatives that might confer an antioxidant effect to the extract were present. Treatment with this extract protected several Saccharomyces cerevisiae strains defective in antioxidant defenses against H2O2 and t-BOOH cytotoxicities, showing a clear antioxidant activity. The effect is the same for all strains used, independent of the antioxidant defense disrupted, suggesting that protection may be due to molecules that act as versatile and wide spectrum nonenzymatic antioxidants, such as vitamins or phytosterols. The extract was not mutagenic in either Salmonella typhimurium or S. cerevisiae and showed a significant antimutagenic action against oxidative mutagens in S. cerevisiae.
authors.affiliation: Departamento de Biofísica, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
authors.forename: Renato Moreira
authors.initials: RM
authors.lastname: Rosa
authors.forename: Maria Inés S
authors.initials: MI
authors.lastname: Melecchi
authors.forename: Rafael
authors.initials: R
authors.lastname: da Costa Halmenschlager
authors.forename: Fernanda C
authors.initials: FC
authors.lastname: Abad
authors.forename: Cristina Rosat
authors.initials: CR
authors.lastname: Simoni
authors.forename: Elina B
authors.initials: EB
authors.lastname: Caramão
authors.forename: João Antonio Pêgas
authors.initials: JA
authors.lastname: Henriques
authors.forename: Jenifer
authors.initials: J
authors.lastname: Saffi
authors.forename: Ana Lígia Lia
authors.initials: AL
authors.lastname: de Paula Ramos
mesh_terms: D016587:Antimutagenic Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D035264:Flowers / Q000737:chemistry*; D031584:Hibiscus / Q000737:chemistry*; D000432:Methanol; D009152:Mutagenicity Tests; D010936:Plant Extracts / Q000494:pharmacology*
chemical_list: D016587:Antimutagenic Agents; D000975:Antioxidants; D010936:Plant Extracts; D000432:Methanol