Extracellular localization of the diterpene sclareol in clary sage (Salvia sclarea L., Lamiaceae)

PLoS One. 2012;7(10):e48253. doi: 10.1371/journal.pone.0048253. Epub 2012 Oct 25.

Abstract

Sclareol is a high-value natural product obtained by solid/liquid extraction of clary sage (Salvia sclarea L.) inflorescences. Because processes of excretion and accumulation of this labdane diterpene are unknown, the aim of this work was to gain knowledge on its sites of accumulation in planta. Samples were collected in natura or during different steps of the industrial process of extraction (steam distillation and solid/liquid extraction). Samples were then analysed with a combination of complementary analytical techniques (gas chromatography coupled to a mass spectrometer, polarized light microscopy, environmental scanning electron microscopy, two-photon fluorescence microscopy, second harmonic generation microscopy). According to the literature, it is hypothesized that sclareol is localized in oil pockets of secretory trichomes. This study demonstrates that this is not the case and that sclareol accumulates in a crystalline epicuticular form, mostly on calyces.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chemistry, Organic / methods
  • Crystallization
  • Diterpenes / chemistry
  • Gas Chromatography-Mass Spectrometry / methods
  • Gene Expression Regulation, Plant
  • Ions
  • Mass Spectrometry / methods
  • Microscopy, Electron, Scanning / methods
  • Oils
  • Plant Extracts / chemistry
  • Plant Proteins / metabolism
  • Salvia / metabolism*
  • Temperature
  • Terpenes

Substances

  • Diterpenes
  • Ions
  • Oils
  • Plant Extracts
  • Plant Proteins
  • Terpenes
  • sclareol

Grants and funding

This work is part of the Claryssime Programme (http://www.claryssime.fr/) supervised by CD, and including a PostDoc grant to SL. Claryssime is funded by “Pôle de Compétitivité Parfums, Arômes, Senteurs, Saveurs”, “Direction Générale de la Compétitivité, de l’Industrie et des Services” and “Région Rhône-Alpes”. Laser microscopy is funded by Université Jean Monnet, CNRS and Leica Microsystem. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.