title: Isolation of antifungal saponins from Phytolacca tetramera, an Argentinean species in critic risk.
abstract: The methanolic extract of the berries of Phytolacca tetramera, an Argentinean species submitted to a great anthropic impact, and therefore in critic risk of extinction, not previously studied, showed antifungal activity against opportunistic pathogenic fungi. Through fractionation of the extract followed by agar dilution assays, three monodesmosidic triterpenoid saponins have been isolated from the butanolic extract of P. tetramera. The structures were established as phytolaccosides: B [3-O-beta-D-xylopiranosyl-phytolaccagenin], E [3-O-beta-D-glucopyranosyl-(1-->4)-beta-D-xylopiranosyl-phytolaccagenin]. and F [3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-xylopyranosyl-phytolaccagenic acid]. The three saponins belong to the olean-type triterpenoid saponins, with 28,30 dicarboxylic groups and an olefinic double bond on C-12. Phytolaccosides B and E but not phytolaccoside F, showed antifungal activities against a panel of human pathogenic opportunistic fungi. Phytolaccoside B was the most active compound and showed the broadest spectrum of action. The most sensitive fungus was Trichophyton mentagrophytes.
authors.affiliation: Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Escalante
authors.forename: Carina B
authors.initials: CB
authors.lastname: Santecchia
authors.forename: Silvia N
authors.initials: SN
authors.lastname: López
authors.forename: Martha A
authors.initials: MA
authors.lastname: Gattuso
authors.forename: Angel
authors.initials: A
authors.lastname: Gutiérrez Ravelo
authors.forename: Franco
authors.initials: F
authors.lastname: Delle Monache
authors.forename: Manuel
authors.initials: M
authors.lastname: Gonzalez Sierra
authors.forename: Susana A
authors.initials: SA
authors.lastname: Zacchino
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry* / Q000494:pharmacology; D001118:Argentina; D015169:Colony Count, Microbial; D005658:Fungi / Q000187:drug effects; D009682:Magnetic Resonance Spectroscopy; D000432:Methanol; D009828:Oleanolic Acid / Q000031:analogs & derivatives / Q000737:chemistry* / Q000302:isolation & purification / Q000494:pharmacology; D029603:Phytolacca / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry; D018514:Plant Structures / Q000737:chemistry; D012503:Saponins / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology; D014315:Triterpenes / Q000737:chemistry* / Q000302:isolation & purification* / Q000494:pharmacology
chemical_list: D000935:Antifungal Agents; D010936:Plant Extracts; D012503:Saponins; D014315:Triterpenes; C472597:phytolaccoside B; D009828:Oleanolic Acid; D000432:Methanol