A database of high-resolution MS/MS spectra for lichen metabolites

Abstract

While analytical techniques in natural products research massively shifted to liquid chromatography-mass spectrometry, lichen chemistry remains reliant on limited analytical methods, Thin Layer Chromatography being the gold standard. To meet the modern standards of metabolomics within lichenochemistry, we announce the publication of an open access MS/MS library with 250 metabolites, coined LDB for Lichen DataBase, providing a comprehensive coverage of lichen chemodiversity. These were donated by the Berlin Garden and Botanical Museum from the collection of Siegfried Huneck to be analyzed by LC-MS/MS. Spectra at individual collision energies were submitted to MetaboLights (https://www.ebi.ac.uk/metabolights/MTBLS999) while merged spectra were uploaded to the GNPS platform (CCMSLIB00004751209 to CCMSLIB00004751517). Technical validation was achieved by dereplicating three lichen extracts using a Molecular Networking approach, revealing the detection of eleven unique molecules that would have been missed without LDB implementation to the GNPS. From a chemist’s viewpoint, this database should help streamlining the isolation of formerly unreported metabolites. From a taxonomist perspective, the LDB offers a versatile tool for the chemical profiling of newly reported species.

Neuroprotective and Anti-Inflammatory Effects of Evernic Acid in an MPTP-Induced Parkinson’s Disease Model

“…To date, more than 20,000 species have been identified. Lichens produce several secondary metabolites, such as depside, depsidone, xanthone, and dibenzofuran, which have been used in foods, perfumes, and medicines, and as dyes [ 6 , 7 , 8 ]. Furthermore, the metabolites produced by lichens exhibit antioxidant, antimicrobial, anticancer, antiviral, and anti-inflammatory effects [ 9 , 10 , 11 , 12 , 13 ].…”

“…Oakmoss is commercially harvested at ~700 tons annually in south-central Europe for the French fragrance industry [ 14 ]. Evernic acid (EA) is a major component of Evernia prunastri and is also an abundant metabolite in Hypogymnia physodes , Ophioparma ventosa, Ramalina species, and others and is classified as a depside with two monoaromatic rings [ 8 ]. Studies have reported EA is biologically active and that it severely inhibits the growths of the pathogenic fungi Pythium ultimum and Phytophthora infestans [ 15 ].…”

Salazinic Acid-Derived Depsidones and Diphenylethers with α-Glucosidase Inhibitory Activity from the Lichen Parmotrema dilatatum

“…Diverse and specific stablyassociated bacterial cohorts were reported for many lichen species [13], and the highly complex lichen holobiont was recently demonstrated to include basidiomycete yeasts, challenging the traditional notion of lichens comprising a single unique fungus [14]. The specific lifestyle of lichenized fungi is associated with a unique chemodiversity, which essentially corresponds to polymalonate-derived phenolic compounds [15,16]. As of 2020, lichens are still deemed to constitute a largely untapped source of bioactive specialized metabolites [17].…”

Molecular Network-Guided Alkaloid Profiling of Aerial Parts of Papaver nudicaule L. Using LC-HRMS

“…Our main interest is to highlight the species-specific metabolites and propose a reliable alkaloid profile. Therefore, this study utilized the Global Natural Products Social (GNPS) molecular networking platform and significantly accelerated the MS/MS-based clustering of alkaloids, even for compounds with no spectral matches in any public database or in-house MS/MS library [14,15].…”