title: Extracellular localization of the diterpene sclareol in clary sage (Salvia sclarea L., Lamiaceae).
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.
authors.affiliation: Laboratoire de Biotechnologies Végétales Appliquées aux Plantes Aromatiques et Médicinales, Université Jean Monnet, Université de Lyon, Saint-Etienne, France. caissard@univ-st-etienne.fr
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Caissard
authors.forename: Thomas
authors.initials: T
authors.lastname: Olivier
authors.forename: Claire
authors.initials: C
authors.lastname: Delbecque
authors.forename: Sabine
authors.initials: S
authors.lastname: Palle
authors.forename: Pierre-Philippe
authors.initials: PP
authors.lastname: Garry
authors.forename: Arthur
authors.initials: A
authors.lastname: Audran
authors.forename: Nadine
authors.initials: N
authors.lastname: Valot
authors.forename: Sandrine
authors.initials: S
authors.lastname: Moja
authors.forename: Florence
authors.initials: F
authors.lastname: Nicolé
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Magnard
authors.forename: Sylvain
authors.initials: S
authors.lastname: Legrand
authors.forename: Sylvie
authors.initials: S
authors.lastname: Baudino
authors.forename: Frédéric
authors.initials: F
authors.lastname: Jullien
mesh_terms: D002625:Chemistry, Organic / Q000379:methods; D003460:Crystallization; D004224:Diterpenes / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D018506:Gene Expression Regulation, Plant; D007477:Ions; D013058:Mass Spectrometry / Q000379:methods; D008855:Microscopy, Electron, Scanning / Q000379:methods; D009821:Oils; D010936:Plant Extracts / Q000737:chemistry; D010940:Plant Proteins / Q000378:metabolism; D027544:Salvia / Q000378:metabolism*; D013696:Temperature; D013729:Terpenes
chemical_list: D004224:Diterpenes; D007477:Ions; D009821:Oils; D010936:Plant Extracts; D010940:Plant Proteins; D013729:Terpenes; C070760:sclareol