title: Antifungal activity of extracts and prenylated coumarins isolated from Baccharis darwinii Hook & Arn. (Asteraceae).
abstract: The petroleum ether extract of Baccharis darwinii showed activity against Cryptococcus neoformans and dermatophytes. Bioactivity-guided fractionation of Baccharis darwinii has resulted in the isolation of three coumarins: 5'-hydroxy aurapten (anisocoumarin H, 1), aurapten (7-geranyloxycoumarin, 2) and 5'-oxoaurapten (diversinin, 3). The structures of these compounds were characterized by spectroscopic methods. These compounds were evaluated for their antimicrobialactivity against a panel of each, bacteria and fungi. Compound 3 showed the best activities against Microsporum gypseum, Trichophyton rubrum and Trichophyton mentagrophytes with MICs = 15.6 microg/mL, followed by compound 1 whose MICs against the same fungi were 62.5 microg/mL. In addition they showed fungicidal rather than fungistatic activity. Both compounds showed moderate activity (MICs = 125 microg/mL) against Cryptococcus neoformans. This is the first report of the presence of compound 1 in B. darwinii.
authors.affiliation: Laboratorio de Productos Naturales Patagónicos (LAPRONAP), Facultad de Ciencias Naturales, Universidad Nacional de la Patagonia San Juan Bosco, Km 4, CP 9000, Comodoro Rivadavia, Chubut, Argentina. rkurdelas@unpata.edu.ar
authors.forename: Rita R
authors.initials: RR
authors.lastname: Kurdelas
authors.forename: Beatriz
authors.initials: B
authors.lastname: Lima
authors.forename: Alejandro
authors.initials: A
authors.lastname: Tapia
authors.forename: Gabriela Egly
authors.initials: GE
authors.lastname: Feresin
authors.forename: Manuel
authors.initials: M
authors.lastname: Gonzalez Sierra
authors.forename: María Victoria
authors.initials: MV
authors.lastname: Rodríguez
authors.forename: Susana
authors.initials: S
authors.lastname: Zacchino
authors.forename: Ricardo D
authors.initials: RD
authors.lastname: Enriz
authors.forename: Monica L
authors.initials: ML
authors.lastname: Freile
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification*; D031175:Baccharis / Q000737:chemistry*; D001419:Bacteria / Q000187:drug effects; D003374:Coumarins / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology; D005658:Fungi / Q000187:drug effects; D008826:Microbial Sensitivity Tests; D015394:Molecular Structure; D010936:Plant Extracts / Q000032:analysis / Q000494:pharmacology*; D054876:Prenylation; D013057:Spectrum Analysis
chemical_list: D000935:Antifungal Agents; D003374:Coumarins; D010936:Plant Extracts