Saponins from Allium minutiflorum with antifungal activity

Phytochemistry. 2007 Mar;68(5):596-603. doi: 10.1016/j.phytochem.2006.10.009. Epub 2006 Nov 21.

Abstract

Three saponins, named minutoside A (1), minutoside B (2), minutoside C (3), and two known sapogenins, alliogenin and neoagigenin, were isolated from the bulbs of Allium minutiflorum Regel. Elucidation of their structure was carried out by comprehensive spectroscopic analyses, including 2D NMR spectroscopy and mass spectrometry. The structures of the new compounds were identified as (25R)-furost-2alpha,3beta,6beta,22alpha,26-pentaol 3-O-[beta-D-xylopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-galactopyranosyl] 26-O-beta-D-glucopyranoside (1), (25S)-spirostan-2alpha,3beta,6beta-triol 3-O-beta-D-xylopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-galactopyranoside (2), and (25R)-furost-2alpha,3beta,5alpha,6beta,22alpha,26-esaol 3-O-[beta-D-xylopyranosyl-(1-->3)-O-beta-D-glucopyranosyl-(1-->4)-O-beta-D-galactopyranosyl] 26-O-beta-D-glucopyranoside (3). The isolated compounds were evaluated for their antimicrobial activity. All the novel saponins showed a significant antifungal activity depending on their concentration and with the following rank: minutoside B>minutoside C>>minutoside A. No appreciable antibacterial activity was recorded. The possible role of these saponins in plant-microbe interactions is discussed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Allium / chemistry*
  • Antifungal Agents / chemistry
  • Antifungal Agents / isolation & purification
  • Antifungal Agents / pharmacology
  • Bacteria / drug effects
  • Carbohydrate Sequence
  • Fungi / drug effects
  • Glycosides / chemistry
  • Glycosides / isolation & purification
  • Glycosides / pharmacology
  • Magnetic Resonance Spectroscopy
  • Models, Molecular
  • Saponins / chemistry*
  • Saponins / isolation & purification
  • Saponins / pharmacology*
  • Spectrometry, Mass, Electrospray Ionization
  • Steroids / chemistry
  • Steroids / isolation & purification
  • Steroids / pharmacology

Substances

  • Antifungal Agents
  • Glycosides
  • Saponins
  • Steroids
  • minutoside A
  • minutoside B