8 research outputs found
A Method for the Simultaneous Determination of Chlorogenic Acid and Sesquiterpene Lactone Content in Industrial Chicory Root Foodstuffs
A method for the simultaneous determination of free chlorogenic acids (CGA) and sesquiterpene lactones (STL) in chicory root and its dried (flour) and roasted (grain) forms is described. The method uses one extraction and one analysis for all chicory root products. Various solvents with low to high polarity, such as methanol, chloroform, or n-hexane, were tested alone, in combination in different proportions or with acidified or neutral aqueous solvent. The water/chloroform/methanol (30/30/40, v/v/v) mixture generated the best extraction yield, 21% higher than alcohol mixtures. The profiling of CGA and STL content was performed through a conventional HPLC-DAD method using a PFP core shell column in a fast single run. Good retention time and area repeatability (RDD mean % 0.46 and 5.6, resp.) and linearity (R2≥0.96) were obtained. The STL and chlorogenic acids levels determined were 254.7 and 100.2 μg/g of dry matter in the root, 792.5 and 1,547 μg/g in flour, and 160.4 and 822.5 μg/g in the roasted grains, respectively. With an average recovery of 106% and precision of 90%, this method is rapid, reproducible, and straightforward way to quantify the chlorogenic acids and STL in chicory raw material and end products
Uncatalysed intermolecular aza-Michael reactions
International audienc
Oxygenated lanostane-type triterpenes profiling in laccate Ganoderma chemotaxonomy
Oxygenated lanostane-type triterpenes (OLTT), including ganoderic acids and lucidenic acids produced by fungi of the genus Ganoderma (Polyporales), are abundantly documented for their potential pharmacological value. In order to test the correlation between species identity and OLTT composition, methanolic extracts of seven laccate Ganoderma species were analyzed by liquid chromatography coupled to mass spectrometry. OLTT profiles of each species were compared to a phylogenetic reconstruction of Ganoderma based on ITS rDNA sequences. The results suggest a high specificity in OLTT composition in one of the phylogenetic lineages of Ganoderma that encompasses tropical species, when no OLTT compound was detected in other lineages (including the European G. lucidum and the Asian G. sinense). Within the OLTT-positive lineage, G. sichuanense, G. martinicense, and G. tuberculosum (Asian-tropicum clade) were characterized by a specific composition in ganoderic acids and G. curtisii by a variety of lucidenic acids. An unidentified OLTT was found in G. resinaceum, also equivocally positioned in phylogenetic analyses. These results confirm OLTT as a suitable taxonomic marker in a lineage of pharmacologically and economically valuable species. Correlations with phylogeny, and development of OLTT composition as a fingerprint tool for quality control, could be an issue to address next, based on a more complete species sampling
Safe and Efficient Sigma1 Ligand: A Potential Drug Candidate for Multiple Sclerosis
Multiple Sclerosis (MS) is an autoimmune demyelinating and neurodegenerative disease of the central nervous system (CNS). Current management strategies suppress or modulate immune function, all with consequences and known side effects. They demonstrate a high level of success in limiting new relapses. However, the neurodegenerative process still affects both grey and white matter in the central nervous system. The sigma1 (S1R) ligand-regulated chaperone is implicated in many biological processes in various CNS-targeted diseases, acting on neural plasticity, myelination and neuroinflammation. Among the proteins involved in MS, S1R has therefore emerged as a promising new target. Standard and robust methods have been adopted to analyze the adsorption, distribution, metabolism, excretion (ADME) properties, safety pharmacology and toxicology of a previously synthetized simple benzamide-derived compound with nanomolar affinity for S1R, high selectivity, no cytotoxicity and good metabolic stability. The compound was also characterized as an agonist based on well-validated assays prior to in vivo investigations. Interestingly, we found that the oral administration of this compound resulted in an overall significant reduction in clinical progression in an MS experimental model. This effect is mediated through S1R action. Our results further suggest the potential use of this compound in the treatment of MS
Fig. 1 in Antimicrobial prenylated benzoylphloroglucinol derivatives and xanthones from the leaves of Garcinia goudotiana
Fig. 1. Compounds isolated from Garcinia goudotiana.Published as part of <i>Mahamodo, Sania, Rivière, Céline, Neut, Christel, Abedini, Amin, Ranarivelo, Heritiana, Duhal, Nathalie, Roumy, Vincent, Hennebelle, Thierry, Sahpaz, Sevser, Lemoine, Amélie, Razafimahefa, Dorothée, Razanamahefa, Bakonirina, Bailleul, François & Andriamihaja, Bakolinirina, 2014, Antimicrobial prenylated benzoylphloroglucinol derivatives and xanthones from the leaves of Garcinia goudotiana, pp. 162-168 in Phytochemistry 102</i> on page 163, DOI: 10.1016/j.phytochem.2014.03.006, <a href="http://zenodo.org/record/10489862">http://zenodo.org/record/10489862</a>
Gold(I)-Catalysed Asymmetric Hydroamination of Alkenes: A Silver- and Solvent-Dependent Enantiodivergent Reaction
International audienceIn the present study, we report the first silver dependent enantiodivergent gold catalysed reaction. The asymmetric intramolecular hydroamination of alkenes catalysed by the combination of a single chiral binuclear gold(I) chloride complex and silver perchlorate can afford both enantiomers of the products by a simple solvent change from toluene to methanol. Such an enantiodivergent reaction is strictly independent of the nature of the catalyst anion or the reaction temperature and displays the same first-order kinetic rate law with respect to substrate concentration in both solvents. Beyond a simple solvent effect, the enantioinversion is controlled by gold-silver chloride adducts which occur only in methanol and allow a dual activation of the reagent. While one single gold atom activates the alkene moiety, the other gold atom forms an oxophilic gold-silver chloride adduct which interacts with the carbamate function. By comparison with toluene which affords (S)-enantiomer, this proximal and bimetallic activation allows an opposite stereodifferentiation of the two diastereomeric intermediates during the final protodeauration step and leads therefore to the (R)-enantiomer