Isolation of antifungal saponins from Phytolacca tetramera, an Argentinean species in critic risk.
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.
Escalante
Andrea M
AM
Farmacognosia, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, Suipacha 531, 2000 Rosario, Argentina.
Santecchia
Carina B
CB
López
Silvia N
SN
Gattuso
Martha A
MA
Gutiérrez Ravelo
Angel
A
Delle Monache
Franco
F
Gonzalez Sierra
Manuel
M
Zacchino
Susana A
SA
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
D000935:Antifungal Agents; D010936:Plant Extracts; D012503:Saponins; D014315:Triterpenes; C472597:phytolaccoside B; D009828:Oleanolic Acid; D000432:Methanol