In situ DART-MS as a Versatile and Rapid Dereplication Tool in Lichenology: Chemical Fingerprinting of Ophioparma ventosa.
BACKGROUND
Lichens widely occur all over the world and are known to produce unique secondary metabolites with various biological activities.


OBJECTIVE
To develop high-throughput screening approaches requiring little to no sample preparation to alleviate the dereplication holdup and accelerate the discovery workflow of new structures from lichens.


METHODS
The extracellular distribution of lichen metabolites is incentive for in situ chemical profiling of lichens using the ambient mass spectrometry DART-MS. For this purpose, the chlorolichen Ophioparma ventosa, producing an array of lichen polyphenolics that encompass the main structural classes associated to lichen chemodiversity, represented a relevant model to assess the versatility of this platform. The feasibility of this approach was first established by analysing the pure compounds known from this species prior to being extended to different solid organs of the lichen.


RESULTS
All tested compounds could be detected in positive and negative ion modes, most often with prevalent protonated or deprotonated molecules. Only depsides underwent a significant in-source fragmentation in both ionisation modes, which should be regarded as an added value for their structural elucidation. In situ DART-MS analyses of Ophioparma ventosa provided an extensive chemical profile and noteworthy pinpointed miriquidic acid, an unusual lichen depside so far unknown within this species. At last, in situ DART-MS granted a first insight into the distribution of the metabolites within the lichen.


CONCLUSIONS
DART-MS represents a versatile tool to the wide field of lichenology, facilitating accelerated and sharp analyses of lichens and bypassing costly and tedious procedures of solvent extraction. Copyright © 2016 John Wiley & Sons, Ltd.
Laboratoire de Pharmacognosie, Equipe PNSCM (ISCR UMR CNRS 6226), Faculté des Sciences Pharmaceutiques et Biologiques, 2 av. du Pr Léon-Bernard, 35042, Rennes Cedex, France.
Pierre
P
Le Pogam
Laboratoire de Pharmacognosie, Equipe PNSCM (ISCR UMR CNRS 6226), Faculté des Sciences Pharmaceutiques et Biologiques, 2 av. du Pr Léon-Bernard, 35042, Rennes Cedex, France. anne-cecile.le-lamer@univ-tlse3.fr.|Université Paul Sabatier Toulouse 3, 118 Route de Narbonne, 31062, Toulouse Cedex 09, France. anne-cecile.le-lamer@univ-tlse3.fr.
Anne-Cécile
AC
Le Lamer
Laboratoire de Pharmacognosie, Equipe PNSCM (ISCR UMR CNRS 6226), Faculté des Sciences Pharmaceutiques et Biologiques, 2 av. du Pr Léon-Bernard, 35042, Rennes Cedex, France.
Béatrice
B
Legouin
Laboratoire de Pharmacognosie, Equipe PNSCM (ISCR UMR CNRS 6226), Faculté des Sciences Pharmaceutiques et Biologiques, 2 av. du Pr Léon-Bernard, 35042, Rennes Cedex, France.
Joël
J
Boustie
Institut d'Electronique et de Télécommunication de Rennes (IETR UMR CNRS 6164), Université de Rennes 1, Campus de Beaulieu, 263 Avenue du General Leclerc, 35042, Rennes Cedex, France. david.rondeau@univ-rennes1.fr.|Département de Chimie, Université de Bretagne Occidentale, 6 avenue le Gorgeu, 29238, Brest Cedex 03, France. david.rondeau@univ-rennes1.fr.
David
D
Rondeau
D002851:Chromatography, High Pressure Liquid; D008011:Lichens / Q000737:chemistry*; D013058:Mass Spectrometry
Lichens; in situ DART-MS; polyphenolics