A5012914866- Lichen and fungal ecology
- Botany and Plant Ecology Studies
- Bryophyte Studies and Records
- Mycorrhizal Fungi and Plant Interactions
- Medicinal plant effects and applications
- Plant Pathogens and Fungal Diseases
- melanin and skin pigmentation
- Phytochemical compounds biological activities
- Analytical Chemistry and Chromatography
- Geology and Paleoclimatology Research
- Biocrusts and Microbial Ecology
- Complementary and Alternative Medicine Studies
- Oral Health Pathology and Treatment
- Phytochemicals and Antioxidant Activities
- Synthesis and biological activity
- Plant Toxicity and Pharmacological Properties
- Fungal Biology and Applications
- Polar Research and Ecology
- Microbial Natural Products and Biosynthesis
- Metabolomics and Mass Spectrometry Studies
- Allergic Rhinitis and Sensitization
- Sesquiterpenes and Asteraceae Studies
- Hibiscus Plant Research Studies
- Drug-Induced Hepatotoxicity and Protection
- Fern and Epiphyte Biology
Institut des Sciences Chimiques de Rennes
2015-2024
Université de Rennes
2015-2024
Centre National de la Recherche Scientifique
2015-2024
Université Européenne de Bretagne
2010-2016
Institut de Chimie
2007-2012
Pharmac
2008
Australian National University
2007
Laboratoire de Synthèse Organique
2003
Two new beta-orcinol depsidones, 1 and 2, together with 13 known compounds were isolated from the lichen Usnea articulata. The structures of 2 elucidated by spectroscopic analyses those comparison their data literature values or direct authentic standards. Compounds 1, 5 exhibited moderate antiradical activity in 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. depsidones 4 showed better superoxide anion scavenging (IC50 = 566 580 microM, respectively) than quercetin 754 microM).
A thorough phytochemical study of Stereocaulon evolutum was conducted, for the isolation structurally related atranorin derivatives. Indeed, pilot experiments suggested that (1), main metabolite this lichen, would interfere with lifecycle hepatitis C virus (HCV). Eight compounds, including one reported first time (2), were isolated and characterized. Two analogs (5, 6) also synthesized, to enlarge panel atranorin-related structures. Most these compounds active against HCV, a half-maximal...
The extreme resiliency of lichens to UV radiations makes them an interesting model find new photoprotective agents acting as UV-blockers and antioxidant. In this research, using a in vitro method designed overcome the shortage material associated many studies dealing with natural products, we show that three major compounds isolated from lichen Vulpicida pinastri, vulpinic acid, pinastric acid usnic were blocker agents. Antioxidant assays evidenced superoxide anion scavenging activity....
Abstract Imaging mass spectrometry techniques have become a powerful strategy to assess the spatial distribution of metabolites in biological systems. Based on auto-ionisability lichen using LDI-MS, we herein image major secondary (specialized metabolites) from Ophioparma ventosa by LDI-MSI (Mass Spectrometry Imaging). Such technologies offer tremendous opportunities discuss role natural products through mapping, their patterns being consistent with previous chemical ecology reports. A...
Three natural flavonols compounds have been isolated from the ethyl acetate fraction of Scurrula ferruginea Danser (Loranthaceae). Besides quercetin and quercitrin, an unusual flavonol glycoside 4"-O-acetylquercitrin was isolated. Structures were determined using spectroscopic methods including UV, NMR HRMS-EI. The incidence 4"-O-acetylquercitrin, not previously reported in Loranthaceae, is discussed. Cytotoxic evaluation on four human cancer cell lines showed to be most active with IC50 35...
Abstract The phytochemical study of Stereocaulon montagneanum harvested in Sumatra (Indonesia) led to the isolation 11 known compounds including two metabolites not previously described genus , peristictic acid ( 8 ) and menegazziaic 10 ). complete 1 H 13 C NMR spectral assignments stictic derivatives are reported with some revisions. Five depsidones belonging chemosyndrome were superoxide anion scavengers as potent ascorbic no toxicity on human cell lines.
Presence and identity of secondary metabolites are two the main components lichen taxonomy. Aromatic compounds formed via acetyl-polymalonate pathway most studied substances. In addition, derived from mevalonic acid (e.g., terpenes steroids) sometimes detected in medulla. However, their value as diagnostic characters genus Usnea yet poorly understood despite fact that they were mentioned several taxonomical papers. We conclude i) aside previously recognized polyphenolic compounds,...
Abstract The composition of fatty acids (FAs) is known to discriminate families within genera bacteria, fungi, octocorals and algae. Here, we applied the more sensitive gas chromatographic (GC) analysis investigate taxonomic value using FA 15 species lichen, including three chlorolichens (two Cladonia Stereocaulon scutelligerum ), nine tripartite lichens ( species) cyanolichens Lichina pygmaea , Collema cristatum Peltigera membranacea ). One macroscopic cyanobacterium Nostoc sp.),...
Screening of the antifungal activities ten Guadeloupean plants was undertaken to find new extracts and formulations against superficial mycoses such as onychomycosis, athlete's foot, Pityriasis versicolor, well deep fungal infection Pneumocystis pneumonia. For first time, CMI these plant [cyclohexane, ethanol ethanol/water (1:1, v/v)] determined five dermatophytes, Candida species, Scytalidium dimidiatum , a Malassezia sp. strain carinii . Cytotoxicity tests most active were also performed...
Abstract Introduction In recent years, LC‐MS has become the golden standard for metabolomic studies. Indeed, LC is relatively easy to couple with soft electrospray ionization. As a consequence, many tools have been developed structural annotation of tandem mass spectra. However, it sometimes difficult do data‐dependent acquisition (DDA), especially when developing new methods that stray from classical workflow. Objective An old tool petroleomics recently gained popularity in metabolomics,...
Two mycosporines were isolated for the first time in two chlorolichen species, <i>Dermatocarpon luridum</i> and miniatum</i>. Mycosporine glutaminol (<b>1</b>) mycosporine glutamicol (<b>2</b>) along with ethyl ester of (<b>3</b>), which was formed during purification process. Aqueous extracts pure then investigated their antioxidant activities photoprotective properties photostability photocytotoxicity. Semi-purified fractions much more than lichen aqueous crude extracts. Compound <b>3</b>...
Sciadonic acid (Scia; 20:3Δ5,11,14) is a distinctive fatty (FA) with polymethylene-interrupted double bond at C5. It specifically found in seeds from gymnosperms such as pine nuts. Published papers describe decrease liver and plasma triacylglycerols rats fed this nutriment. The present study seeks to identify the action mechanism of Scia on triacylglycerol synthesis. In way, its nutritional effect FA metabolism involving Stearoyl-CoA Desaturase 1 (SCD1) investigated.Scia discerned trace...
Roccella species constitute interesting models to address questions regarding lichen metabolite diversity across taxonomic, ecological and geographic gradients. Indeed, owing their wide distribution, taxonomic the narrow niche they occupy, are good candidates study drivers of chemistry. This focuses on chemical profiling five species: R. applanata, belangeriana, fuciformis, montagnei phycopsis. These were sampled in a rather longitudinal range (1°51′W 47°17′E) covering Eastern Atlantic...
Abstract Thin-layer chromatography (TLC) still enjoys widespread popularity among lichenologists as one of the fastest and simplest analytical strategies, today remaining primary method assessing secondary product content lichens. The pitfalls associated with this approach are well known TLC leads to characterizing compounds by comparison standards rather than properly identifying them, which might lead erroneous assignments, accounting for long-held interest in hyphenating dedicated...
Spectral analysis of lichen extracts obtained by MIR-FEWS permits to discriminate species and the identification their major compounds. is a rapid, efficient convenient tool for metabolic profiling.