Chemical diversity of five coastal Roccella species from mainland France, the Scattered Islands, and São Tomé and Príncipe

Abstract

Roccella species constitute interesting models to address questions regarding lichen metabolite diversity across taxonomic, ecological and geographic gradients. Indeed, owing to their wide distribution, their taxonomic diversity and the narrow ecological niche they occupy, Roccella species are good candidates to study the drivers of lichen chemistry. This study focuses on the chemical profiling of five species: R. applanata, R. belangeriana, R. fuciformis, R. montagnei and R. phycopsis. These five species were sampled in a rather narrow longitudinal range (1°51′W to 47°17′E) covering the Eastern Atlantic and Western Indian Ocean areas along an extended latitudinal range (48°49′N to 22°23′S). High Pressure Liquid Chromatography (HPLC) analysis followed by mass spectrometry of 31 Roccella thalli revealed a number of interesting patterns through a multivariate (PCA) analysis, including the first detailed chemical profiles for two species from the Scattered Islands: R. applanata and R. belangeriana. Metabolite segregation amongst all studied Roccella species, including R. montagnei and R. belangeriana, gave some insight into the taxonomy of the latter two species, which we interpret as separate species. An additional analysis focusing on R. montagnei samples revealed chemical differences along both a latitudinal and ecological gradient (from Europa Island to São Tomé and Príncipe). Three mass spectra databases were built to dereplicate the ions, which gave an overview of the factors that could drive quantitative and qualitative metabolite composition in lichens. Additionally, several new Roccella species records are reported for the Scattered Islands, as well as São Tomé and Príncipe.

The genus Ramalina (Ascomycota, Lecanoromycetes, Ramalinaceae) from the Scattered Islands (French Southern and Antarctic Lands), with descriptions of three new species

“…However, H. foertherianum constitutes rather vast shrublands in this territory, which was shown from the Glorioso Islands to be a suitable phorophyte for Ramalina species. Another notable result is that, despite (Ferron et al 2020). So, when considering Roccella genus from the Scattered Islands, the species with asexual dispersal means seem to have better dispersal abilities, however, this cannot be generalized to the Ramalina species from these territories, for which sexual or asexual dispersal strategy seems to result both in rather low dispersal abilities.…”

“…After evaporation of the solvents, all dried extracts were weighed to prepare a solution at a concentration of 1 mg⋅mL -1 in methanol. All extracts were filtered (0.45 µm) before being subjected to high-performance liquid chromatography coupled with diode-array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-MS) with the method previously reported (Ferron et al 2020). In addition, three custom chemical databases were used: the HLDB built with authentic lichen standards, the RamalinaDB built from an extensive bibliography on compounds identified in Ramalina species coupled with their predicted retention time and their molecular weight, and the LDB-MS1, a database built by Damien Olivier-Jimenez (Ferron et al 2020).…”

Antibiotic and Nematocidal Metabolites from Two Lichen Species Collected on the Island of Lampedusa (Sicily)

“…(+)-Montagnetol has been previously found in different Roccella species, including R. phycopsis [ 48 ] and R. montagnei [ 21 ]. The study by Basset et al (2009) [ 49 ] confirmed its stereochemistry synthetizing both epimers.…”

A New Cryptic Lineage in Parmeliaceae (Ascomycota) with Pharmacological Properties

“…Deconvolution was then applied using the ADAP Wavelets algorithm. Dereplication was gathered through our laboratory database called HLDB [ 49 ], and relative quantities of the major products were determined by integration of the UV chromatograms at 254 nm.…”