[Bjonnh.net]# _

# Categories/

science


You can read more about my research topics by looking at my academic profile or publications, talks and posters.
Authors: Adriano Rutz ORCID , Maria Sorokina , Jakub Galgonek , Daniel Mietchen , Egon Willighagen , Arnaud Gaudry , James G. Graham ORCID , Ralf Stephan , Roderic Page , Jiří Vondrášek , Christoph Steinbeck ORCID , Guido F. Pauli ORCID , Jean-Luc Wolfender ORCID , Jonathan Bisson ORCID , Pierre-Marie Allard ORCID
Journal: bioRxiv
Subjects:
Contemporary bioinformatic and chemoinformatic capabilities hold promise to reshape knowledge management, analysis and interpretation of data in natural products research. Currently, reliance on a disparate set of non-standardized, insular, and specialized databases presents a series of challenges to data access, either within the discipline or to integration and interoperability between related domains. The fundamental elements of exchange are referenced structure-organism pairs that establish relationships between distinct molecular structures and the living organisms from which they were identified.
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categories publications science
Authors: David Ribnicky , Seon Beom Kim , Alexander Poulev , Yang Wang , Anik Boudreau , Ilya Raskin , Jonathan Bisson ORCID , G. Joseph Ray , Shao-Nong Chen ORCID , Allison Richard , Jacqueline M. Stephens , Guido F. Pauli ORCID
Journal: Journal of Natural Products (RoMEO status: White)
Subjects:
Two new diprenylated coumaric acid isomers (1a and 1b) and two known congeners, capillartemisin A (2) and B (3), were isolated from Artemisia scoparia as bioactive markers using bioactivity-guided HPLC fractionation. Their structures were determined by spectroscopic means, including 1D and 2D NMR methods and LC-MS, with their purity assessed by 1D 1H pure shift qNMR spectroscopic analysis. The bioactivity of compounds was evaluated by enhanced accumulation of lipids, as measured using Oil Red O staining, and by increased expression of several adipocyte marker genes, including adiponectin in 3T3-L1 adipocytes relative to untreated negative controls.
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categories publications science
Authors: Seon Beom Kim , Jonathan Bisson ORCID , J. Brent Friesen ORCID , Luca Bucchini , Stefan Gafner , David C. Lankin ORCID , Shao-Nong Chen ORCID , Guido F. Pauli ORCID , James B. McAlpine ORCID
Journal: Journal of Natural Products (RoMEO status: White)
Subjects:
NMR
Curcuma longa (turmeric) has an extensive history of ethnomedical use for common ailments, and “curcumin”-containing dietary supplements (CDS) are a highly visible portion of today’s self-medication market. Owing to raw material cost pressure, CDS products are affected by economically motivated, nefarious adulteration with synthetic curcumin (“syncumin”), possibly leading to unexpected toxicological issues due to “residual” impurities. Using a combination of targeted and untargeted (phyto)chemical analysis, this study investigated the botanical integrity of two commercial “turmeric” CDS with vitamin and other additives that were associated with reported clinical cases of hepatotoxicity.
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categories publications science
Authors: Kathryn M. Nelson ORCID , Jonathan Bisson ORCID , Gurpreet Singh ORCID , James G. Graham ORCID , Shao-Nong Chen ORCID , J. Brent Friesen ORCID , Jayme L. Dahlin ORCID , Matthias Niemitz ORCID , Michael A. Walters ORCID , Guido F. Pauli ORCID
Journal: Journal of Medicinal Chemistry (RoMEO status: White)
Subjects:
This Perspective of the published essential medicinal chemistry of cannabidiol (CBD) provides evidence that the popularization of CBD-fortified or CBD-labeled health products and CBD-associated health claims lacks a rigorous scientific foundation. CBD’s reputation as a cure-all puts it in the same class as other “natural” panaceas, where valid ethnobotanicals are reduced to single, purportedly active ingredients. Such reductionist approaches oversimplify useful, chemically complex mixtures in an attempt to rationalize the commercial utility of natural compounds and exploit the “natural” label.
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categories publications science
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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categories publications science
Authors: Seon Beom Kim , Jonathan Bisson ORCID , J. Brent Friesen ORCID , Guido F. Pauli ORCID , Charlotte Simmler ORCID
Journal: Journal of Natural Products (RoMEO status: White)
Subjects:
CPC
CCC
Chlorophylls are present in all extracts from the aerial parts of green plant materials. Chlorophylls may act as in vitro bioassay nuisance compounds, possibly preventing the reproducibility and accurate measurement of readouts due to their UV/vis absorbance, fluorescence properties, and tendency to precipitate in aqueous media. Despite the diversity of methods used traditionally to remove chlorophylls, details about their mode of operation, specificity, and reproducibility are scarce. Herein, we report a selective and efficient 45 min liquid–liquid/countercurrent chlorophyll cleanup method using Centrifugal Partition Chromatography (CPC) with a solvent system composed of hexanes–EtOAc–MeOH–water (5:5:5:5, v/v) in elution-extrusion mode.
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categories publications science
Authors: Mary P. Choules ORCID , Jonathan Bisson ORCID , Charlotte Simmler ORCID , James B. McAlpine ORCID , Gabriel Giancaspro , Anton Bzhelyansky , Matthias Niemitz ORCID , Guido F. Pauli ORCID
Journal: Journal of Pharmaceutical and Biomedical Analysis (RoMEO status: V2)
Subjects:
NMR
Whereas generic, LC-based pharmaceutical control quality procedures depend largely on the detection mode and can be particularly ‘blind’ to certain impurities, NMR is a more versatile and, thus, often more judicious detector. While adulteration presents ever-evolving challenges for the analysis of active pharmaceutical ingredients (APIs) and finished products sold in the worldwide (online) marketplace, research chemicals are usually trusted rather than being considered flawed or even adulterated. This report shows how NMR analysis uncovered the unanticipated presence of substantial amounts of mannitol (20 and 43% w/w) as undeclared constituent in two custom synthetic peptides, DR and DRVYI, that were sourced commercially.
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categories publications science
Authors: Adriano Rutz ORCID , Miwa Dounoue-Kubo , Simon Ollivier , Jonathan Bisson ORCID , Mohsen Bagheri , Tongchai Saesong , Samad Nejad Ebrahimi , Kornkanok Ingkaninan , Jean-Luc Wolfender ORCID , Pierre-Marie Allard ORCID
Journal: Frontiers in Plant Science (RoMEO status: Green)
Subjects:
Mass spectrometry (MS) offers unrivalled sensitivity for the metabolite profiling of complex biological matrices encountered in natural products (NP) research. The massive and complex sets of spectral data generated by such platforms require computational approaches for their interpretation. Within such approaches, computational metabolite annotation automatically links spectral data to candidate structures via a score, which is usually established between the acquired data and experimental or theoretical spectral databases (DB). This process leads to various candidate structures for each MS features.
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categories publications science
Authors: Mary P. Choules ORCID , Jonathan Bisson ORCID , Wei Gao , David C. Lankin ORCID , James B. McAlpine ORCID , Matthias Niemitz ORCID , Birgit U. Jaki ORCID , Scott G. Franzblau ORCID , Guido F. Pauli ORCID
Journal: Journal of Organic Chemistry (RoMEO status: White)
Subjects:
NMR
Ensuring identity, purity, and reproducibility are equally essential during synthetic chemistry, drug discovery, and for pharmaceutical product safety. Many peptidic APIs are large molecules that require considerable effort for integrity assurance. This study builds on quantum mechanical 1H iterative Full Spin Analysis (HiFSA) to establish NMR peptide sequencing methodology that overcomes the intrinsic limitations of principal compendial methods in identifying small structural changes or minor impurities that affect effectiveness and safety.
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categories publications science
Authors: James B. McAlpine ORCID , Shao-Nong Chen ORCID , Andrei Kutateladze ORCID , John B. MacMillan , Giovanni Appendino ORCID , Andersson Barison , Mehdi A. Beniddir ORCID , Maique W. Biavatti ORCID , Stefan Bluml , Asmaa Boufridi ORCID , Mark S. Butler ORCID , Robert J. Capon , Young H. Choi , David Coppage , Phillip Crews ORCID , Michael T. Crimmins , Marie Csete ORCID , Pradeep Dewapriya , Joseph M. Egan ORCID , Mary J. Garson , Gregory Genta-Jouve ORCID , William H. Gerwick ORCID , Harald Gross , Mary Kay Harper , Precilia Hermanto , James M. Hook , Luke Hunter , Damien Jeannerat ORCID , Nai-Yun Ji ORCID , Tyler A. Johnson , David G. I. Kingston ORCID , Hiroyuki Koshino , Hsiau-Wei Lee , Guy Lewin , Jie Li ORCID , Roger G. Linington , Miaomiao Liu , Kerry L. McPhail ORCID , Tadeusz F. Molinski ORCID , Bradley S. Moore ORCID , Joo-Won Nam ORCID , Ram P. Neupane , Matthias Niemitz ORCID , Jean-Marc Nuzillard ORCID , Nicholas H. Oberlies ORCID , Fernanda M. M. Ocampos ORCID , Guohui Pan ORCID , Ronald J. Quinn , D. Sai Reddy , Jean-Hugues Renault ORCID , José Rivera-Chávez , Wolfgang Robien ORCID , Carla M. Saunders ORCID , Thomas J. Schmidt ORCID , Christoph Seger , Ben Shen ORCID , Christoph Steinbeck ORCID , Hermann Stuppner , Sonja Sturm , Orazio Taglialatela-Scafati , Dean J. Tantillo ORCID , Robert Verpoorte ORCID , Bin-Gui Wang ORCID , Craig M. Williams ORCID , Philip G. Williams , Julien Wist ORCID , Jian-Min Yue ORCID , Chen Zhang , Zhengren Xu ORCID , Charlotte Simmler ORCID , David C. Lankin ORCID , Jonathan Bisson ORCID , Guido F. Pauli ORCID
Journal: Natural Product Reports (RoMEO status: Yellow)
Subjects:
NMR
With contributions from the global natural product (NP) research community, and continuing the Raw Data Initiative, this review collects a comprehensive demonstration of the immense scientific value of disseminating raw nuclear magnetic resonance (NMR) data, independently of, and in parallel with, classical publishing outlets. A comprehensive compilation of historic to present-day cases as well as contemporary and future applications show that addressing the urgent need for a repository of publicly accessible raw NMR data has the potential to transform natural products (NPs) and associated fields of chemical and biomedical research.
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categories publications science
Authors: Pierre-Marie Allard ORCID , Jonathan Bisson ORCID , Antonio Azzollini ORCID , Guido F. Pauli ORCID , Geoffrey A Cordell , Jean-Luc Wolfender ORCID
Journal: Current Opinion in Biotechnology (RoMEO status: Green)
Subjects:
Humans have co-evolved alongside numerous other organisms, some having a profound effect on health and nutrition. As the earliest pharmaceutical subject, pharmacognosy has evolved into a meta-discipline devoted to natural biomedical agents and their functional properties. While the acquisition of expanding data volumes is ongoing, contextualization is lagging. Thus, we assert that the establishment of an integrated and open databases ecosystem will nurture the discipline. After proposing an epistemological framework of knowledge acquisition in pharmacognosy, this study focuses on recent computational and analytical approaches.
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categories publications science
A circular slide-ruler
We had this conference in Chicago in 2016. As I was playing with the laser-cutter and making planetary motion devices see Here, I also was playing with the idea of circular slide rulers. As the calculation of elution volumes and retention in CCC and CPC are using multiplications and divisions it is possible to do these on a circular slide ruler (or a normal one) by using logarithmic scales (because additions in that space correspond to multiplications in linear scale).
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categories science hack
Someone toying with a laser-cut award
We had [this conference](https://gfp.people.uic.edu/ccc2016/) in Chicago in 2016. As I was playing with the laser-cutter and making planetary motion devices, Guido asked if it wouldn't be possible to make two awards for the conference. I also made a [Slide ruler](/article/20170530_cccslider) for that conference. A bit of design, metallic-gold acrylic, flexible metallic with black background acrylic for the tag, and a piece of wood made by a colleague (Jim).
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categories science hack
Authors: Kathryn M. Nelson ORCID , Jayme L. Dahlin ORCID , Jonathan Bisson ORCID , James Graham , Guido F. Pauli ORCID , Michael A. Walters ORCID
Journal: Journal of Medicinal Chemistry (RoMEO status: White)
Subjects:
Curcumin is a constituent (up to ∼5%) of the traditional medicine known as turmeric. Interest in the therapeutic use of turmeric and the relative ease of isolation of curcuminoids has led to their extensive investigation. Curcumin has recently been classified as both a PAINS (pan-assay interference compounds) and an IMPS (invalid metabolic panaceas) candidate. The likely false activity of curcumin in vitro and in vivo has resulted in >120 clinical trials of curcuminoids against several diseases.
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categories publications science
Authors: Rasika S. Phansalkar , Charlotte Simmler ORCID , Jonathan Bisson ORCID , Shao-Nong Shen , David C. Lankin ORCID , James B. McAlpine ORCID , Matthias Niemitz ORCID , Guido F. Pauli ORCID
Journal: Journal of Natural Products (RoMEO status: White)
Subjects:
NMR
Chemical standardization, along with morphological and DNA analysis ensures the authenticity and advances the integrity evaluation of botanical preparations. Achievement of a more comprehensive, metabolomic standardization requires simultaneous quantitation of multiple marker compounds. Employing quantitative 1H NMR (qHNMR), this study determined the total isoflavone content (TIfCo; 34.5–36.5% w/w) via multimarker standardization and assessed the stability of a 10-year-old isoflavone-enriched red clover extract (RCE). Eleven markers (nine isoflavones, two flavonols) were targeted simultaneously, and outcomes were compared with LC-based standardization.
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categories publications science
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: Jonathan Bisson ORCID , Charlotte Simmler ORCID , Shao-Nong Chen ORCID , J. Brent Friesen ORCID , David C. Lankin ORCID , James McAlpine , Guido F. Pauli ORCID
Journal: Natural Product Reports (RoMEO status: Yellow)
Subjects:
NMR
The notion of data transparency is gaining a strong awareness among the scientific community. The availability of raw data is actually regarded as a fundamental way to advance science by promoting both integrity and reproducibility of research outcomes. Particularly, in the field of natural product and chemical research, NMR spectroscopy is a fundamental tool for structural elucidation and quantification (qNMR). As such, the accessibility of original NMR data, i.e., Free Induction Decays (FIDs), fosters transparency in chemical research and optimizes both peer review and reproducibility of reports by offering the fundamental tools to perform efficient structural verification.
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categories publications science
Authors: Pierre-Marie Allard ORCID , Tiphaine Péresse , Jonathan Bisson ORCID , Katia Gindro , Laurence Marcourt , Van Cuong Pham , Fanny Roussi , Marc Litaudon , Jean-Luc Wolfender ORCID
Journal: Analytical Chemistry (RoMEO status: White)
Subjects:
MS
Dereplication represents a key step for rapidly identifying known secondary metabolites in complex biological matrices. In this context, liquid-chromatography coupled to high resolution mass spectrometry (LC-HRMS) is increasingly used and, via untargeted data-dependent MS/MS experiments, massive amounts of detailed information on the chemical composition of crude extracts can be generated. An efficient exploitation of such data sets requires automated data treatment and access to dedicated fragmentation databases. Various novel bioinformatics approaches such as molecular networking (MN) and in-silico fragmentation tools have emerged recently and provide new perspective for early metabolite identification in natural products (NPs) research.
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categories publications science
Authors: Guido F. Pauli ORCID , Matthias Niemitz ORCID , Jonathan Bisson ORCID , Michael W. Lodewyk , Cristian Soldi , Jared T. Shaw , Dean J. Tantillo ORCID , Jordy M. Saya , Klaas Vos , Roel A. Kleinnijenhuis , Henk Hiemstra , Shao-Nong Chen ORCID , James McAlpine , David C. Lankin ORCID , J. Brent Friesen ORCID
Journal: Journal of Organic Chemistry (RoMEO status: White)
Subjects:
NMR
FID
The revision of the structure of the sesquiterpene aquatolide from a bicyclo[2.2.0]hexane to a bicyclo[2.1.1]hexane structure using compelling NMR data, X-ray crystallography, and the recent confirmation via full synthesis exemplify that the achievement of “structural correctness” depends on the completeness of the experimental evidence. Archived FIDs and newly acquired aquatolide spectra demonstrate that archiving and rigorous interpretation of 1D 1H NMR data may enhance the reproducibility of (bio)chemical research and curb the growing trend of structural misassignments.
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categories publications science
Authors: Jonathan Bisson ORCID , James McAlpine , J. Brent Friesen ORCID , Shao-Nong Chen ORCID , James Graham , Guido F. Pauli ORCID
Journal: Journal of Medicinal Chemistry (RoMEO status: White)
Subjects:
IMP
High-throughput biology has contributed a wealth of data on chemicals, including natural products (NPs). Recently, attention was drawn to certain, predominantly synthetic, compounds that are responsible for disproportionate percentages of hits but are false actives. Spurious bioassay interference led to their designation as pan-assay interference compounds (PAINS). NPs lack comparable scrutiny, which this study aims to rectify. Systematic mining of 80+ years of the phytochemistry and biology literature, using the NAPRALERT database, revealed that only 39 compounds represent the NPs most reported by occurrence, activity, and distinct activity.
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categories publications science
Authors: Ariene A. Leme , Cristina M.P. Vidal , A.B.S. Sousa , Rasika Phansalkar , Joo-Won Nam ORCID , Jonathan Bisson ORCID , Shao-Nong Chen ORCID , Guido F. Pauli ORCID , Ana Bedran-Russo
Journal: Dental Materials (RoMEO status: Green)
Subjects:
NMR
Plant derived proanthocyanidins are well-established compounds exhibiting high dentin biomodification potency. Among the effects, enhanced tissue biomechanics and biostability are of relevance to restorative dentistry. This study evaluated the adhesive properties of an enriched proanthocyanidin primer on the bond strength of experimental resin-based adhesives containing variable concentrations of HEMA.

categories publications science
Authors: Joo-Won Nam ORCID , Rasika Phansalkar , David C. Lankin ORCID , Jonathan Bisson ORCID , James McAlpine , Ariene A. Leme , Cristina M.P. Vidal , Benjamin Ramirez , Matthias Niemitz ORCID , Ana Bedran-Russo , Shao-Nong Chen ORCID , Guido F. Pauli ORCID
Journal: Journal of Organic Chemistry (RoMEO status: White)
Subjects:
NMR
The ability of certain oligomeric proanthocyanidins (OPACs) to enhance the biomechanical properties of dentin involves collagen cross-linking of the 1.3–4.5 nm wide space via protein–polyphenol interactions. A systematic interdisciplinary search for the bioactive principles of pine bark has yielded the trimeric PAC, ent-epicatechin-(4β→8)-epicatechin-(2β→O→7,4β→8)-catechin (3), representing the hitherto most potent single chemical entity capable of enhancing dentin stiffness. Building the case from two congeneric PAC dimers, a detailed structural analysis decoded the stereochemistry, spatial arrangement, and chemical properties of three dentin biomodifiers.
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categories publications science
A cat that has been transformed
This article is in english, but the original one is in french. Just because many english-speaking people asked me about these transforms. (Cet article est en anglais, même si l’original est en français. C’est juste parceque on m’a plus souvent demandé en anglais qu’en français plus d’informations sur ce sujet. Mais ça devrait être plutôt clair pour les francophones.) Through my migration to o-blog v2.5 I found some old experiments I did with FFT related to this Rapport d’écoute - Sur les épaules de Darwin (France Inter) - La forme des mots
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category science
Authors: Cristina M.P. Vidal , Ariene A. Leme , Thaiane R. Aguiar , Rasika Phansalkar , Joo-Won Nam ORCID , Jonathan Bisson ORCID , James McAlpine , Shao-Nong Chen ORCID , Guido F. Pauli ORCID , Ana Bedran-Russo
Journal: Langmuir (RoMEO status: White)
Subjects:
NMR
Proanthocyanidins (PACs) are secondary plant metabolites that mediate nonenzymatic collagen cross-linking and enhance the properties of collagen based tissue, such as dentin. The extent and nature of cross-linking is influenced by the composition and specific chemical structure of the bioactive compounds present in certain PAC-rich extracts. This study investigated the effect of the molecular weight and stereochemistry of polyphenol compounds on two important properties of dentin, biomechanics, and biostability. For that, purified phenols, a phenolic acid, and some of its derivatives were selected: PAC dimers (A1, A2, B1, and B2) and a trimer (C1), gallic acid (Ga), its esters methyl-gallate (MGa) and propyl-gallate (PGa), and a pentagalloyl ester of glucose (PGG).
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categories publications science
Authors: Ariene A. Leme , Cristina M.P. Vidal , Thaiane R. Aguiar , A.B.S. Sousa , Rasika Phansalkar , Joo-Won Nam ORCID , Jonathan Bisson ORCID , Shao-Nong Chen ORCID , Guido F. Pauli ORCID , Ana Bedran-Russo
Journal: Dental Materials (RoMEO status: Green)
Subjects:
NMR
The polyphenol source and molecular structure complexity affects interactions of proanthocyanidins (PACs) with dentin matrix. Therefore, this study evaluated the dentin bioactivity of compounds from a non-galloylated PACs-rich extract.

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: Guido F. Pauli ORCID , Shao-Nong Chen ORCID , David C. Lankin ORCID , Jonathan Bisson ORCID , Ryan J. Case , Lucas R. Chadwick , Tanja Gödecke , Taichi Inui , Aleksej Krunic , Birgit U. Jaki ORCID , James B. McAlpine ORCID , Shunyan Mo , José G. Napolitano , Jimmy Orjala , Juuso Lehtivarjo , Samuli-Petrus Korhonen , Matthias Niemitz ORCID
Journal: Journal of Natural Products (RoMEO status: White)
Subjects:
NMR
The present study demonstrates the importance of adequate precision when reporting the δ and J parameters of frequency domain 1H NMR (HNMR) data. Using a variety of structural classes (terpenoids, phenolics, alkaloids) from different taxa (plants, cyanobacteria), this study develops rationales that explain the importance of enhanced precision in NMR spectroscopic analysis and rationalizes the need for reporting Δδ and ΔJ values at the 0.1–1 ppb and 10 mHz level, respectively.
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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
A cat that has been transformed

Suite à l’émission de France Inter « Sur les épaules de Darwin, La forme des mots », j’ai décidé d’expérimenter un peu avec la conversion d’images en sons par transformée inverse de fourier.

Pour cela, j’ai utilisé le logiciel ARSS, un peu vieillot, mais qui fait ce qu’il a à faire.

Commençons par un petit exemple, transformons l’image de la formule de cette fameuse transformée en son avec la commande :

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category 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
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