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Authors: Julien Gabaston , Thierry Buffeteau , Thierry Brotin , Jonathan Bisson ORCID , Caroline Rouger , Jean-Michel Mérillon , Pierre Waffo-Téguo
Journal: Phytochemistry Letters
Subjects:
NMR
In a continuing search for neuroprotective stilbenoids, two uncommon diastereomeric stilbenoid glucosides, africanoside A (1) and B (2) as well as fifteen known stilbenes, E-resveratrol, E-gnetifolin E, E-piceid, E-resveratroloside, E-gnetifolin K, E-gnetol, E-isorhapontigenin, E-isorhapontin, E-isorhapontigenin-4′-O-glucopyranoside, E-gnetin C, E-bisisorhapontigenin B, E-gnemonoside A, E-gnemonoside C, E-gnemonoside D, and E-gnetin E, were isolated from rhizomes of Gnetum africanum, using a combination of centrifugal partition chromatography and preparative HPLC. The structure of these two stilbenoids was investigated by NMR, vibrational circular dichroism (VCD), and electronic circular dichroism (ECD) experiments.
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Authors: Jonathan Bisson ORCID , Marion Brunel , Alain Badoc , Grégory Da Costa , Tristan Richard , Jean-Michel Mérillon , Pierre Waffo-Téguo
Journal: Analytical Chemistry (RoMEO status: White)
Subjects:
CPC
NMR
SPE
Centrifugal partition chromatography (CPC) and all countercurrent separation apparatus provide chemists with efficient ways to work with complex matrixes, especially in the domain of natural products. However, despite the great advances provided by these techniques, more efficient ways of analyzing the output flow would bring further enhancement. This study describe a hyphenated approach made by coupling NMR with CPC through a hybrid-indirect coupling made possible by using a solid phase extraction (SPE) apparatus intended for high-pressure liquid chromatography (HPLC)-NMR hyphenation.
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categories publications science
Authors: Yorgos Papastamoulis , Jonathan Bisson ORCID , Hamza Temsamani , Tristan Richard , Axel Marchal , Jean-Michel Mérillon , Pierre Waffo-Téguo
Journal: Tetrahedron (RoMEO status: Green)
Subjects:
CPC
Stilbenoids have received increasing attention over the last two decades since the discovery of resveratrol in wine. With an ever-growing rhythm, a multitude of biological activities of naturally occurring stilbenes are being reported. In this work, we investigated minor stilbenoid compounds from Vitis vinifera stalks. The compounds were purified by means of centrifugal partition chromatography (CPC), a countercurrent-separation technique. Electrospray ionization–ion trap mass spectrometry (ESI–IT-MS) after optimization proved to be extremely efficient for the detection of these new molecules, providing both structural information for structure elucidation and a means to achieve identification even with minute amounts.
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categories publications science
Authors: Thierry Buffeteau , Dominique Cavagnat , Jonathan Bisson ORCID , Axel Marchal , Gilbert D. Kapche , Ilaria Battistini , Gregory Da Costa , Alain Badoc , Jean-Pierre Monti , Jean-Michel Mérillon , Pierre Waffo-Téguo
Journal: Journal of Natural Products (RoMEO status: White)
Subjects:
VCD
Dimeric stilbene glucosides 1–3 [two diastereomers of (−)-gnemonoside A (1a and 1b), (−)-gnemonoside C (2), and (−)-gnemonoside D (3)] as well as a mixture of the two enantiomers of gnetin C (4) were isolated from the rhizomes of Gnetum africanum. The two enantiomers of gnetin C, (+)-4 and (−)-4, were obtained from the aglycones of 1a and 1b, respectively. The configurations of these stilbenoids were investigated by NMR and vibrational circular dichroism (VCD) experiments.
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categories publications science
Authors: Carole Lambert , Tristan Richard , Elodie Renouf , Jonathan Bisson ORCID , Pierre Waffo-Téguo , Louis Bordenave , Nathalie Ollat , Jean-Michel Mérillon , Stéphanie Cluzet
Journal: Journal of Agricultural and Food Chemistry (RoMEO status: White)
Subjects:
NMR
Grapevine canes are rich in resveratrol and its complex derivatives. These compounds have many biological activities and are needed mainly for health purposes. Canes, which are often wasted, can be used to produce these high-value compounds at low cost. We studied sixteen Vitis vinifera L. cultivars among the most widely cultivated ones worldwide. Polyphenols were extracted from their canes and identified by liquid chromatography–nuclear magnetic resonance spectroscopy. We accurately determined the content of E-ε-viniferin, E-resveratrol, E-piceatannol, and vitisin B and, for the first time, that of hopeaphenol and miyabenol C.
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categories publications science
Authors: Merian Nassra , Stéphanie Krisa , Yorgos Papastamoulis , Gilbert Deccaux Kapche , Jonathan Bisson ORCID , Caroline André , Jan-Pieter Konsman , Jean-Marie Schmitter , Jean-Michel Mérillon , Pierre Waffo-Téguo
Journal: Planta Medica (RoMEO status: Blue)
Subjects:
Microglia-driven inflammatory processes are thought to play an important role in ageing and several neurological disorders. Since consumption of a diet rich in polyphenols has been associated with anti-inflammatory and neuroprotective effects, we studied the effects of twenty-five stilbenoids isolated from Milicia excelsa, Morus alba, Gnetum africanum, and Vitis vinifera. These compounds were tested at 5 and 10 µM on BV-2 microglial cells stimulated with bacterial lipopolysaccharide. Ten stilbenoids reduced lipopolysaccharide-induced nitric oxide production at 5 and/or 10 µM.
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categories publications science
Authors: Davide Slaghenaufi , Stéphanie Marchand-Marion , Tristan Richard , Pierre Waffo-Téguo , Jonathan Bisson ORCID , Jean-Pierre Monti , Jean-Michel Mérillon , Gilles de Revel
Journal: Food Chemistry (RoMEO status: Green)
Subjects:
CPC
Oak
Flavours extracted from oak wood during barrel ageing contribute to the organoleptic character of wines and spirits. The aim of this work was to identify the glycosidic precursors of the key volatile compounds responsible for oak wood aroma. Oak extract is a very complex matrix and, furthermore, precursors are present in very small quantities. Preparative centrifugal partition chromatography (CPC) is a promising solution for purifying the oak extract. The solvent system was selected on the basis of the partition coefficient of glycosidase enzyme activity (Kca).
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categories publications science
Authors: Alison D. Pawlus , Emma Cantos-Villar , Tristan Richard , Jonathan Bisson ORCID , Pascal Poupard , Yorgos Papastamoulis , Jean-Pierre Monti , Pierre-Louis Teissedre , Pierre Waffo-Téguo , Jean-Michel Mérillon
Journal: Journal of Chromatography A (RoMEO status: Green)
Subjects:
Wine is a major dietary source of numerous potentially health promoting stilbenoids that have been the subject of many qualitative and quantitative studies. However, our initial HPLC–MS analyses of crude wine samples demonstrated the presence of compounds with molecular weights matching characteristic stilbenoid dimers, trimers, and tetramers that were unaccounted for in the literature. Due to the likelihood that these are known compounds, a chemical dereplication method is highly desirable. We developed such a method using LC-DAD–MS monitored fractionation steps, using adsorption and centrifugal partition chromatography (CPC), to obtain fractions rich in stilbenoids for analysis in stopped-flow LC–NMR.
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categories publications science
Authors: Alison D. Pawlus , Ramla Sahli , Jonathan Bisson ORCID , Céline Rivière , Jean-Claude Delaunay , Tristan Richard , Eric Gomès , Louis Bordenave , Pierre Waffo-Téguo , Jean-Michel Mérillon
Journal: Journal of Agricultural and Food Chemistry (RoMEO status: White)
Subjects:
NMR
We present stilbenoid profiles of canes from 16 grapevines. Fifteen stilbenoids were obtained through isolation and structure identification using MS, NMR, and [α]D or as commercial standards. An HPLC–UV method for the simultaneous quantification of nine of these stilbenoids was developed and applied to canes of Vitis amurensis, Vitis arizonica, Vitis berlandieri, Vitis betulifolia, Vitis cinerea, Vitis × champini, Vitis × doaniana, Vitis labrusca, Vitis candicans (syn. Vitis mustangensis), Vitis riparia, Vitis rupestris, Vitis vinifera, Muscadinia rotundifolia, and a V.
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categories publications science
Authors: Carole Lambert , Jonathan Bisson ORCID , Pierre Waffo-Téguo , Yorgos Papastamoulis , Tristan Richard , Marie-France Corio-Costet , Jean-Michel Mérillon , Stéphanie Cluzet
Journal: Journal of Agricultural and Food Chemistry (RoMEO status: White)
Subjects:
The interaction between Vitis vinifera and trunk disease fungi requires better understanding. We studied the role of phenolics as possible plant defense compounds in this context. The impact of 24 grapevine phenolic compounds was determined on 6 major wood decay fungi by an in vitro agar plate assay. Hydroxystilbenoids, especially oligomers such as miyabenol C, isohopeaphenol, and vitisin A and B, greatly reduced the growth of the fungi, except that of Phaeoacremonium aleophilum.
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categories publications science

# Conferences/

Hyphenating countercurrent chromatography with NMR and mass spectrometry. How to enhance the range of the liquid phases

Countercurrent chromatography techniques are increasingly used in the fractionation and purification steps of natural products due to their excellent versatility and efficiency. However, one of the major bottlenecks in liquid-liquid chromatography is the solvent system selection. In this work, a NMR-based analysis of complex solvent mixtures was developed for biphasic system selection and modification. This allowed us to develop more versatile separation conditions, such as gradients. Additionally, we hyphenated our countercurrent chromatography device with NMR and mass spectrometry.
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category conferences
Authors: Jonathan Bisson ORCID , Pascal Poupard , Alison D. Pawlus , Alexandre Pons , Philippe Darriet , Jean-Michel Mérillon , Pierre Waffo-Téguo
Journal: Journal of Chromatography A (RoMEO status: Green)
Subjects:
CPC
MS
The phytochemical study of the root extract of the stilbenoid-rich Vitis riparia × Vitis berlandieri grapevine was carried out by centrifugal partition chromatography (CPC). For this reason, we developed a new elution mode we named back-step, which allowed us to obtain cleaner fractions and a more efficient separation process when used in conjunction with a classical elution approach. Three hydroxystilbenes: (E)-resveratrol, (E)-ɛ-viniferin and (E)-vitisin C, with greater than 90% purity were thus obtained through such process, with minimal sample handling and purification steps.
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categories publications science