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A restoration of highly contaminated garden soil is proposed as a greener alternative to the production of vegetables. Depending on potentially toxic elements and their concentration, ryegrass shoots accumulate these elements in sufficient quantity to be used as a catalyst in organic synthesis. The analysis of Cd, Pb, Zn, Cu, Fe, Mn, and Al in ashes issued from the calcination of ryegrass shoots revealed that the concentration of Zn was highest (&gt, 7000 mg kg&ndash, 1). The ratios between potential Lewis acids (Zn, Cu, Fe, Mn, and Al) to carcinogenic metals (Cd or Pb) were 191 &plusmn, 7 for LA/Cd and 235 &plusmn, 13 for LA/Pb, making the shoots of ryegrass suitable for the production of Zn-rich polymetallic biosourced catalysts. This material was used in the synthesis of idrocilamide under free-solvent condition, providing the drug in a good yield (69.9%). Data show that a limitation of waste, a maximization of the material incorporation in the process, a minimization of the steps, and an optimization of the stoichiometric factor are the main innovative factors in the current process in comparison with those previously reported.

International audience; In this chapter, we present Norine (https://norine.univ-lille.fr/norine), the unique resource dedicated to nonribosomal peptides. First, the content of the knowledgebase and the related tools are described. Then, a study case shows how to query Norine by annotations or structure and how to interpret the obtained results.

International audience; Baillonella toxisperma is a medicinal plant used in northern Gabon to treat microbial diseases. It is a plant well-known by local populations, but very few studies have focused on the molecules responsible for the antibacterial activities of B. toxisperma. This study proposes a dereplication strategy based on molecular networking generated from HPLC-ESI-Q/TOF data, allowing investigation of the molecules responsible for the antibacterial activity of B. toxisperma. From this strategy, eighteen compounds were putatively identified. All of these compounds belonged mainly to five families of natural compounds, including phenylpropanolamines, stilbenes, flavonoids, lignans and phenolic glycosides. The chemical study carried out from the bark of B. toxisperma allowed us to identify, for the first time, compounds such as resveratrol and derivatives, epicatechin, epigallocatechin and epigallocatechin gallate. In addition, antibacterial activity (diffusion method and microdilution) and cytotoxicity (Cell Counting Kit-8 (CCK-8 Assay)) in vitro were evaluated. The crude ethanolic extract, as well as the fractions of B. toxisperma, showed significant antibacterial activity. However, the ethanolic fractions F2 and F4 presented high antibacterial activity compared to the crude extract. Cytotoxicity studies on colon-cancer cells (Caco-2) and human keratinocyte cells (HaCaT) showed moderate cytotoxicity in both cell types. This study clearly shows the therapeutic potential of the ethanolic extract of the bark of B. toxisperma and provides information on the phytochemical composition and bioactive compounds of the plant.

Plant immunity induction with natural biocontrol compounds is a valuable and promising ecofriendly tool that fits with sustainable agriculture and healthy food. Despite the agroeconomic significance of wheat, the mechanisms underlying its induced defense responses remain obscure. We reveal here, using combined transcriptomic, metabolomic and cytologic approach, that the lipopeptide mycosubtilin from the beneficial bacterium Bacillus subtilis, protects wheat against Zymoseptoria tritici through a dual mode of action (direct and indirect) and that the indirect one relies mainly on the priming rather than on the elicitation of plant defense-related mechanisms. Indeed, the molecule primes the expression of 80 genes associated with sixteen functional groups during the early stages of infection, as well as the accumulation of several flavonoids during the period preceding the fungal switch to the necrotrophic phase. Moreover, genes involved in abscisic acid (ABA) biosynthesis and ABA-associated signaling pathways are regulated, suggesting a role of this phytohormone in the indirect activity of mycosubtilin. The priming-based bioactivity of mycosubtilin against a biotic stress could result from an interaction of the molecule with leaf cell plasma membranes that may mimic an abiotic stress stimulus in wheat leaves. This study provides new insights into induced immunity in wheat and opens new perspectives for the use of mycosubtilin as a biocontrol compound against Z. tritici.

International audience; The hop plant (Humulus lupulus L.) has been exploited for a long time for both its brewing and medicinal uses, due in particular to its specific chemical composition. These last years, hop cultivation that was in decline has been experiencing a renewal for several reasons, such as a craze for strongly hopped aromatic beers. In this context, the present work aims at investigating the genetic and chemical diversity of fifty wild hops collected from different locations in Northern France. These wild hops were compared to ten commercial varieties and three heirloom varieties cultivated in the same sampled geographical area. Genetic analysis relying on genome fingerprinting using 11 microsatellite markers showed a high level of diversity. A total of 56 alleles were determined with an average of 10.9 alleles per locus and assessed a significant population structure (mean pairwise FST = 0.29). Phytochemical characterization of hops was based on volatile compound analysis by HS-SPME GC-MS, quantification of the main prenylated phenolic compounds by UHPLC-UV as well as untargeted metabolomics by UHPLC-HRMS and revealed a high level of chemical diversity among the assessed wild ac-cessions. In particular, analysis of volatile compounds revealed the presence of some minor but original com-pounds, such as aromadendrene, allo-aromadendrene, isoledene, fl-guaiene, alpha-ylangene and fl-pinene in some wild accessions; while analysis of phenolic compounds showed high content of fl-acids in these wild accessions, up to 2.37% of colupulone. Genetic diversity of wild hops previously observed was hence supported by their chemical diversity. Sample soil analysis was also performed to get a pedological classification of these different collection sites. Results of the multivariate statistical analysis suggest that wild hops constitute a huge pool of chemical and genetic diversity of this species.

ObjectivesThe host-microbiota co-metabolite trimethylamineN-oxide (TMAO) is linked to increased thrombotic and cardiovascular risks. Here we, sought to i) characterize which host variables contribute to fasting serum TMAO levels in real-life settings ii) identify potential actionable therapeutic means related to circulating TMAO.DesignWe applied “explainable” machine learning, univariate-, multivariate- and mediation analyses of fasting plasma TMAO concentration and a multitude of bioclinical phenotypes in 1,741 adult Europeans of the MetaCardis study. We expanded and validated our epidemiological findings in mechanistic studies in human renal fibroblasts and a murine model of kidney fibrosis following TMAO exposure.ResultsNext to age, kidney function was the primary variable predicting circulating TMAO in MetaCardis, with microbiota composition and diet playing minor, albeit significant roles. Mediation analysis revealed a causal relationship between TMAO and kidney function decline that strengthened at more severe stages of cardiometabolic disease. We corroborated our findings in preclinical models where TMAO exposure augmented conversion of human renal fibroblasts into myofibroblasts and increased kidney scarringin vivo. Mechanistically, TMAO aggravated kidney fibrosis due to ERK1/2 hyperactivation synergistically with TGF-β1 signaling. Consistent with our findings, patients receiving next-generation glucose-lowering drugs with reno-protective properties, had significantly lower circulating TMAO when compared to propensity-score matched control individuals.ConclusionAfter age, kidney function is the major determinant of fasting circulating TMAO in adults. Our findings of lower TMAO levels in individuals medicated with reno-protective anti-diabetic drugs suggests a clinically actionable intervention for decreasing TMAO-associated excess cardiovascular risk that merits urgent investigation in human trials.Data availability statementRaw shotgun sequencing data that support the findings of this study have been deposited in the European Nucleotide Archive with accession codes PRJEB37249, PRJEB38742, PRJEB41311 and PRJEB46098. Serum NMR and urine NMR metabolome data have been uploaded to Metabolights with accession number MTBLS3429; serum GC-MS and isotopically quantified serum metabolites (UPLC–MS/MS) are available from MassIVE with accession numbers MSV000088042 and MSV000088043, respectively.

International audience; Les additifs plastiques, ajoutés aux polymères au cours de leur formulation, participent aux dangers que posent l’utilisation et le rejet de plastique dans l’environnement. Cet impact dit « chimique » a été démontré à de multiples reprises. En effet, une fois dans l’environnement, les additifs plastiques peuvent être libérés de la matrice polymérique et diffuser dans l’eau environnante ou au sein des organismes après ingestion de particules de plastiques. L’utilisation de certains additifs est controversée car ils se sont révélés être toxiques pour l’environnement, les organismes marins et l’Homme. Afin d’avoir une meilleure compréhension de l’impact chimique de ces additifs, il est important de les identifier, et idéalement de les quantifier. Après avoir sélectionné une soixantaine de ces additifs (plastifiants, retardateurs de flammes, antioxydants, …), une méthode unique pour l’analyse de l'ensemble ces molécules a été développée en pyrolyse couplée à la chromatographie gazeuse et la spectrométrie de masse haute résolution (Py-GC-HRMS). La méthode développée à ensuite permis d’identifier la présence de divers additifs plastiques dans des échantillons de barquettes plastiques alimentaires en polypropylène (PP) et en acide polylactique (PLA). Au vu des additifs mis en évidence dans ces échantillons, et du fait de la forte présence de barquettes alimentaires dans l’environnement, une étude complémentaire s’est portée sur l’impact potentiel de ces additifs sur les stades de reproduction et les jeunes stades de vies de l’huitre creuse (Crassostrea gigas) (une espèce sentinelle, ingénieure et mondialement commercialisée), après exposition à des lixiviats de ces échantillons.

International audience; Erismadelphus exsul Mildbr bark is widely used in Gabonese folk medicine. However, little is known about the active compounds associated with its biological activities. In the present study, phytochemical profiling of the ethanolic extract of Erismadelphus exsul was performed using a de-replication strategy by coupling HPLC-ESI-Q/TOF with a molecular network approach. Eight families of natural compounds were putatively identified, including cyclopeptide alkaloids, esterified amino acids, isoflavonoid- and flavonoid-type polyphenols, glycerophospholipids, steroids and their derivatives, and quinoline alkaloids. All these compounds were identified for the first time in this plant. The use of molecular networking obtained a detailed phytochemical overview of this species. Furthermore, antioxidant (2,2-diphenyl-1-picryl-hydrazylhydrate (DPPH) and ferric reducing capacity (FRAP)) and in vitro antimicrobial activities were assessed. The crude extract, as well as fractions obtained from Erismadelphus exsul, showed a better reactivity to FRAP than DPPH. The fractions were two to four times more antioxidant than ascorbic acid while reacting to FRAP, and there was two to nine times less antioxidant than this reference while reacting to DPPH. In addition, several fractions and the crude extract exhibited a significant anti-oomycete activity towards the Solanaceae phytopathogen Phytophthora infestans in vitro, and, at a lower extent, the antifungal activity against the wheat pathogen Zymoseptoria tritici had growth inhibition rates ranging from 0 to 100%, depending on the tested concentration. This study provides new insights into the phytochemical characterization and the bioactivities of ethanolic extract from Erismadelphusexsul bark.

National audience; Environmental pollution from plastics and microplastics (MPs) is a threat to the environment and wildlife on multiple aspects regarding exposition of different hazards. One of them is due to the chemical impact of the organic plastic additives (OPAs). Various additives can be added to polymers during the manufacturing process to modify and improve their physical properties. The analysis of OPAs has shown a growing importance since their use has become controversial as some of the additives were found to be toxic to marine organism and humans. In order to have a better understanding of the chemical impact of those additives, it is important to identify and, ideally quantify the additives included in the polymeric matrices. The analysis of OPAs and polymers is an analytical challenge due to the diversity of their chemical composition, the fact that they are most of the time mixed, and the numerous steps needed for the sample preparation with “conventional” approaches such as solvent extraction (SE). Thus, implementing easy and quick screening analysis methods, able to analyse plastic additives, have become a focus of interest. Pyrolysis coupled to a gas chromatography and a high-resolution mass spectrometer (Py-GC-HRMS) is an analytical tool that enable a relatively quick and easy analysis. This technique minimize or even remove the steps for sample preparation, limiting their potential contamination prior the analysis.The goal of this study is to develop a method using Py-GC-HRMS to identify and, if possible, quantify OPAs included in a polymeric matrix. A single method for the analysis of various selected plastic additives has been implemented and benefits the constitution of a database in GC/MS-Orbitrap with a wide variety of plastic additives. This method has shown its ability to characterise several additives is plastic packaging samples. The development of the quantitative method is still on going.

International audience; Lignin is the second most abundant polymer after cellulose in lignocellulosic biomass. Its aromatic composition and recalcitrant nature make its valorization a major challenge for obtaining low molecular weight aromatics compounds with high value-added from the enzymatic depolymerization of industrial lignins. The oxidation reaction of lignin polymer using laccases alone remains inefficient. Therefore, researches are focused on the use of a laccase-mediator system (LMS) to facilitate enzymatic depolymerization. Until today, the LMS system was studied using water-soluble lignin only (commercial lignins, modified lignins, or lignin model compounds). This work reports a study of three LMS systems to depolymerize the three major industrial lignins (organosolv lignin, Kraft lignin, and sodium lignosulfonate). We show that an enzymatic depolymerization of these lignins can be achieved by LMS using laccase from Trametes versicolor, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt as mediator and a cosolvent (25% of 1,4-dioxane) to enhance the solubilization of lignins.

This first study performed on traditional fruits consumed in North Africa reveals their richness in microorganisms with beneficial attributes like cholesterol lowering capabilities. Blackberries (Rubus sp.), fresh figs (Ficus carica), and prickly pears (Opuntia ficus-indica) are fruits largely and traditionally consumed in Kabylia, a beautiful northern Algerian region. Here, 85 lactic acid bacteria (LAB)-isolates were isolated and identified by MALDI-TOF mass spectrometry. The identified species belong to Lactobacillus and Leuconostoc genera. These 85 LAB-isolates were then assessed for their capabilities to grow under conditions mimicking the gastrointestinal tract, and the resulting data were statistically treated with principal component analysis (PCA). After which, only 26 LAB-isolates were selected and characterized for their genetic relatedness using random amplified polymorphic DNA (RAPD) method. Following the genetic relatedness assessment, only 10 LAB-strains, among which nine Lactobacillus plantarum and one Lactobacillus paracasei were studied for their pathoproperties and some probiotic features. Interestingly, all of these 10 LAB-strains were devoid of adverse effects, but capable to adhere to human epithelial colorectal adenocarcinoma Caco-2 cells. Of note, these 10 LAB-strains exhibited an important in vitro hypocholesteromia effect, in strain-dependent manner. Moreover, the Lactobacillus strains exhibited a high bile salt hydrolase (BSH) activity which was correlated with expression of bsh2, bsh3 and bsh4 genes.

International audience; Physiological parameters such as adiposity and age are likely to infuence protein digestion and utilization. The aim of this study was to evaluate the combined efects of age and adiposity on casein protein and amino acid true digestibility and its postprandial utilization in ratsFour groups were included (n=7/8): 2 months/normal adiposity, 2 months/high adiposity, 11 months/normal adiposity and 11 months/high adiposity. Rats were given a calibrated meal containing 15N-labeled casein (Ingredia, Arras, France) and were euthanized 6 h later. Digestive contents were collected to assess protein and amino acid digestibilities. 15N enrichments were measured in plasma and urine to determine total body deamination. Fractional protein synthesis rate (FSR) was determined in diferent organs using a fooding dose of 13C valine.Nitrogen and amino acid true digestibility of casein was around 95–96% depending on the group and was increased by 1% in high adiposity rats (P=0.04). Higher adiposity levels counteracted the increase in total body deamination (P=0.03) that was associated with older age. Signifcant efects of age (P=0.006) and adiposity (P=0.002) were observed in the muscle FSR, with age decreasing it and adiposity increasing it.This study revealed that a higher level of adiposity resulted in a slight increase in protein and individual amino acid true digestibility values and seemed to compensate for the metabolic postprandial protein alterations observed at older age.

Understanding the interaction between microorganisms is essential for the development of new biocontrol products. The fungus Trichoderma harzianum and the bacteria Bacillus velezensis are exploited for their antagonist activity against phytopathogens. Two coculture strategies of these two microorganisms were developed in order to determine the conditions leading to an interaction which increases the biocontrol activity of this couple, defined in terms of the production of lipopeptides by the bacteria. The culture medium essentially varies between these two strategies. The two media differ depending on the availability of nutrients for the microorganisms. In the medium where Bacillus and Trichoderma have all the necessary elements for their growth, the bacteria thrives at the expense of the fungus thanks to its faster growth rate and the production of antifungal lipopeptides. Sequential inoculation of Trichoderma followed by Bacillus solved these problems preventing the coexistence of the two microorganisms. However, in all of these approaches, the presence of Trichoderma did not influence the production of lipopeptides by B. velezensis and consequently its activity in biocontrol. The effect on the production of these NRPs is most noticeable in a minimal medium designed to impose a nutritional dependence between Bacillus and Trichoderma. The bacteria's requirement for a nitrogen source provided by T. harzianum, mainly in the form of peptides and amino acids, allows them to coexist in coculture. The physical presence of the fungus inhibits the production of lipopeptides, but the presence of its supernatant promotes it. The molecular dialogue between the Trichoderma - Bacillus couple needs to be further deciphered in order to exploit it in agricultural applications.; La compréhension de l’interaction entre les microorganismes est primordiale pour le développement de nouveaux produits de biocontrôle. Le champignon Trichoderma harzianum et la bactérie Bacillus velezensis sont exploités pour leur potentiel dans la lutte contre les phytopathogènes. Deux stratégies de coculture de ces deux microorganismes sont mises au point afin de déterminer les conditions menant à une interaction qui augmente l’activité de biocontrôle de ce couple, définie en termes de production de lipopeptides par la bactérie. Le milieu de culture varie essentiellement entre ces deux stratégies. Les deux milieux varient en fonction de la disponibilité de nutriments pour les microorganismes. Dans un milieu riche, où Bacillus et Trichoderma disposent de tous les éléments nécessaires à leur croissance, la bactérie se développe au dépriment du champignon grâce à son rythme de croissance plus rapide et à la production des lipopeptides antifongiques. L’inoculation séquentielle de Trichoderma suivi par Bacillus permet de résoudre ces problèmes empêchant la coexistence des deux microorganismes. Toutefois, dans toutes ces approches, la présence de Trichoderma n’a pas influencé la production de lipopeptides par B. velezensis GA1 et conséquemment son activité en biocontrôle. L’effet sur la production de ces NRPs est plus remarqué dans un milieu minimum conçu pour imposer une dépendance nutritionnelle entre Bacillus et Trichoderma. Le requis de la bactérie d’une source d’azote produite par T. harzianum, principalement sous forme de peptides et d’acides aminés, leur permet de coexister en coculture. La présence physique du champignon inhibe la production de lipopeptides mais la présence de son surnageant la promeut. Le dialogue moléculaire entre le couple Trichoderma – Bacillus requiert d’être décrypté davantage afin de l’exploiter dans des applications agricoles.

Bovine cruor, a slaughterhouse waste, is produced in large quantities all around the world. This co-product was mainly composed of hemoglobin, a protein rich in bioactive peptides after its enzymatic hydrolysis. However, during conventional hydrolysis, chemical agents are necessary to adjust/regulate the pH of the solution and the final hydrolysates produced contain high levels of mineral salts. Therefore, in this study, it is proposed to apply, for the first time, a green technology, named electrodialysis with bipolar membrane (EDBM), as an alternative method to the conventional enzymatic hydrolysis of hemoglobin to obtain purified bioactive peptides. The main objectives of the present thesis were to test the feasibility of this new process to produce bioactive peptides from bovine hemoglobin, to establish the optimal conditions, to avoid membrane fouling and to apply a new original « multiple-step » EDMB process allowing the production of demineralized bioactive peptides without the addition of chemical salts. Bipolar/monopolar (anionic or cationic) configurations using the H+ and OH- generated by the bipolar membranes to regulate the pH were investigated and compared to a conventional process using chemical acid and base. The EDBM configuration formed with cationic membranes allowed the production of hydrolysates containing a low concentration of mineral salts but with fouling formation on the cationic membrane, while EDBM configuration formed with anionic membranes allowed the production of hydrolysates without fouling but with a similar salt concentration than the control. Based on these results, a new 3 compartments EDBM configuration was carried-out for denaturing the hemoglobin, inactivating the enzymatic reaction and demineralizing up to 85% the hemoglobin hydrolysate simultaneously. However, a fouling was still observed on the anionic membrane due to hem precipitation. For this reason, an additional step of discoloration was tested before the demineralization to avoid fouling using the electrogenerated acid. The discolored and demineralized peptides recovered showed antioxidant activity, antibacterial activity against many bacterial strains (Gram + and Gram -) and for the first time antifungal activity against many molds and yeasts strains. Moving towards a circular economy, this sustainable technology has found to be effective in performing multiple operations simultaneously and has a great potential for industrial hydrolysis of blood, since it produces purified biopeptides with a low mineral content and can be used as natural preservatives on meat.; Le cruor bovin, déchet des abattoirs est produit en très grande quantité dans le monde. Ce coproduit est composé principalement d'hémoglobine, une protéine riche en peptides bioactifs après son hydrolyse enzymatique. Cependant, lors de l'hydrolyse conventionnelle par la pepsine, des agents chimiques sont nécessaires pour ajuster et réguler le pH de la solution et, les hydrolysats finaux produits contiennent des niveaux élevés en sels minéraux. Pour pallier ces inconvénients, il a été proposé d'appliquer dans cette étude, pour la première fois, une technologie verte, appelée électrodialyse avec membrane bipolaire (EDMB), comme méthode alternative à l'hydrolyse enzymatique conventionnelle de l'hémoglobine afin d’obtenir des peptides bioactifs purifiés. Les objectifs de cette thèse étaient de tester la faisabilité de ce nouveau procédé pour la production de peptides bioactifs à partir d'hémoglobine bovine, d'établir les conditions optimales, d'éviter le colmatage membranaire et d'appliquer un nouveau procédé original d’EDMB à « multiple-étapes » permettant la production de peptides bioactifs déminéralisés sans ajout de produits chimiques. Des configurations bipolaires/monopolaires (anioniques ou cationiques) utilisant les ions H+ et OH- générés par les membranes bipolaires pour réguler le pH ont été étudiées et comparées à un procédé conventionnel utilisant des acides et des bases chimiques. La configuration d’EDMB formée avec les membranes cationiques a permis la production d'hydrolysats contenant une faible concentration en sels minéraux mais avec la présence d’un colmatage sur la membrane cationique, alors que la configuration d’EDMB utilisant des membranes anioniques a permis la production d'hydrolysats sans colmatage mais avec une concentration en sel similaire à celle de l’hydrolyse conventionnelle (contrôle). En se basant sur ces résultats, une nouvelle configuration d’EDMB à 3 compartiments a été mise en place et étudiée pour dénaturer l'hémoglobine, inactiver la réaction enzymatique et déminéraliser à 85% l'hydrolysat peptidique en simultané. Cependant, un colmatage a encore été observé sur la membrane anionique en raison de la précipitation de l'hème. Pour cette raison, une étape supplémentaire de décoloration a été réalisée avant la déminéralisation pour éviter le colmatage en utilisant l'acide électro-généré. Les peptides décolorés et déminéralisés récupérés ont montré une activité antioxydante, une activité antibactérienne contre plusieurs souches bactériennes (Gram + et Gram -) et pour la première fois une activité antifongique contre de nombreuses souches de moisissures et de levures. Dans un contexte d’économie circulaire, cette technologie durable s'avèrerait efficace pour effectuer plusieurs opérations simultanément et présente un potentiel important au niveau industriel pour l'hydrolyse du sang, puisqu'elle produit des bio-peptides purifiés ayant une faible teneur en sels minéraux et pouvant être utilisés comme conservateurs naturels sur la viande.

National audience; La pollution plastique est une menace pour l’environnement et les organismes. Elle les expose à différents dangers. Outre l’impact « physique » lié à l’ingestion de déchets plastique, l’impact « chimique », dû aux additifs plastiques ajoutés aux polymères au cours de leur formulation, est lui aussi problématique. L’utilisation de certains additifs est controversée du fait que certaines molécules se sont révélées être toxiques pour l’environnement, les organismes marins et l’Homme. De ce fait, l’analyse des additifs plastiques montre un intérêt grandissant.Afin d’avoir une meilleure compréhension de l’impact chimique de ces additifs, il est important de les identifier, et idéalement de les quantifier. Leur analyse dans les matrices polymériques est un challenge analytique pour différentes raisons : la diversité de nature chimique des additifs, leur présence généralement en mélange au sein des polymères, ainsi que les nombreuses étapes nécessaires pour la préparation des échantillons avec les approches plus « conventionnelles » telles que l’extraction au solvant. De ce fait, développer des méthodes analytiques relativement faciles et rapides présente un réel intérêt. Ainsi la pyrolyse couplée à la chromatographie gazeuse et la spectrométrie de masse haute résolution (Py-GC-HRMS) est un outil analytique qui permet une analyse relativement facile et rapide d’un échantillon. Cette technique permet de limiter voire de s’affranchir des étapes de préparation des échantillons, limitant alors leur potentielles contaminations avant l’analyse.Le but de cette étude est de développer une méthode en Py-GC-HRMS haute résolution pour l’identification et la quantification d’additifs plastiques organiques. Une méthode unique pour l’analyse de l'ensemble des additifs sélectionnés a été développée et a permis la constitution d’une base de donnée haute résolution contenant une large variété d’additifs plastiques. Cette méthode a ensuite été appliquée sur certains plastifiants dans le but de les quantifier. Elle montre son utilité pour la caractérisation et le dosage d’additifs dans différents échantillons de matrices polymériques.

National audience; En dix ans, les recherches sur les particules plastiques, nano- (NP) et microplastiques (MP), et leurs contaminants associés se sont largement développées. L’amélioration des connaissances de ces familles de contaminant s’étant accrue, les pratiques analytiques ont dû évoluer et être adaptées. La garantie de la qualité des résultats générés ne peut être obtenue que par la mise en commun des expertises, ainsi que la mise en place d’infrastructures et l’utilisation d’appareillages complémentaires.Dans le cadre du CPER Marco, différents laboratoires (Anses, LOG et ULCO) ont mis en place la plateforme 3PAC de façon à partager leurs équipements analytiques, méthodes, expertises et connaissances.En terme d’infrastructure, de nombreuses possibilités existent. Tout d’abord des systèmes d’aquarium avec un environnement contrôlé sont disponibles pour réaliser des études d’exposition. Une pièce « microplastique » permet de réaliser des manipulations (digestion, filtration) sous atmosphère maîtrisée et ainsi limiter les risques de contamination. La caractérisation des particules (taille, forme) peut être réalisée à l’aide de divers équipements : loupes binoculaires ou directement par microscopie via l’utilisation des capteurs optiques du µ-Raman ou du µ-FT-IR. Enfin, l’identification des particules ou des contaminants associés est rendue possible par l’utilisation de techniques complémentaires soit spectroscopiques (µ-Raman, µ-FT-IR), soit spectrométriques (Py-GC/MS et Py-GC/Orbitrap). L’acquisition de nouveaux équipements, complémentaires, est programmée de façon à venir enrichir les possibilités analytiques (microscopie confocale, technologie light scattering).Dès aujourd’hui, l’expertise des différents partenaires permet de couvrir un large champ de recherches allant des études en laboratoire, aux prélèvements sur le terrain. A titre d’exemple, des travaux récents ont porté sur l’étude de sédiments et organismes prélevés in situ, la réalisation d’études d’encagement d’organismes marins, ou encore l’exposition de bivalves en conditions contrôlées.Désormais, l’ambition de la plateforme 3PAC est de répondre aux appels à projets nationaux et internationaux portant sur l’étude des particules plastiques et de leurs conséquences. Ces projets seront menés au sein d’un écosystème analytique idoine, regroupant expertises, technologies et infrastructures.

National audience; La pollution plastique est une menace pour l’environnement et les organismes. Elle les expose à différents dangers. Outre l’impact « physique » lié à l’ingestion de déchets plastique, l’impact chimique, dû aux additifs plastiques ajoutés aux polymères au cours de leur formulation, est lui aussi problématique. En effet, une fois dans l’environnement, les additifs plastiques peuvent être libérés de la matrice polymérique et diffuser dans l’eau environnante ou au sein des organismes après ingestion de particules de plastiques. L’utilisation de certains additifs est controversée car ils se sont révélés être toxiques pour l’environnement, les organismes marins ou l’Homme.Afin d’avoir une meilleure compréhension de l’impact de ces additifs sur les organismes, il est important de les identifier et idéalement de les quantifier. L’analyse des additifs plastiques est un challenge analytique pour différentes raisons. En comparaison avec les approches plus "traditionnelles", la pyrolyse couplée à une chromatographie gazeuse et spectrométrie de masse (Py-GC-MS) est un outil analytique qui permet une analyse relativement facile et rapide d’un échantillon. Cette technique permet une analyse quasi-directe des échantillons limitant alors les potentielles contaminations des échantillons lors des étapes de préparation précédant l’analyse.Le but de cette étude est de développer une méthode en Py-GC-MS pour l’identification et, si possible, la quantification d’additifs plastiques organiques. Après avoir sélectionné une soixantaine de ces additifs selon leur nocivité et utilisation (plastifiants, retardateurs de flammes, antioxydants, …), une méthode unique pour l’analyse de l'ensemble ces molécules a été développée et a permis la constitution d’une base de donnée haute résolution. Cette méthode sera appliquée sur divers échantillons pour identifier, voire quantifier, les additifs plastiques contenus dans plusieurs matrices polymériques. De plus, la mise en place d'une méthode de pyrolyse avec un gradient de température permet également de caractériser le type de polymère sur le même échantillon.

The potentialities of front-face fluorescence (FFF) and mid-infrared (MIR) spectroscopies coupled with partial least square regression (PLSR) were compared to predict the lipid oxidation of pound cakes. The level of lipid oxidation in pound cakes determined using classical methods showed some changes. Similarly, the fluorescence emission (305–490 nm) and excitation (252–390 nm) spectra and MIR spectra scanned in the 4000–700 cm−1 region showed some changes in pound cakes as a function of both storage time and the type of oil used in the formulation. The application of PLSR to the MIR spectra, provided excellent predictive results for free fatty acid (R2 = 0.97) and peroxide values (R2 = 0.87). Similar results were obtained from both tryptophan and MIR spectra for the prediction of TOTOX (R2 > 0.86) demonstrating the efficiency of the MIR and FFF spectroscopies to qualify and quantify the level of lipid oxidation in pound cakes.

International audience; Trihydroxycinnamoyl spermidines (THCSpd) are plant specialized metabolites with promising pharmacological activities as antifungals, antibacterial, antiviral, and antidepressant drugs. However, their characterization and potential pharmaceutical exploitation are greatly impaired by the sourcing of these compounds, restricted to the pollen of core Eudicot plant species. In this work, we developed a precursor-directed biosynthesis of THCSpd in yeast using a dual enzymatic system based on 4-coumarate-CoA ligases (4CL) and spermidine N-hydroxycinnamoyltransferases (SHT). The system relies on the yeast endogenous spermidine pool and only requires hydroxycinnamic acids as exogenous precursors. By exploring 4CL isoforms and SHT diversity among plants, we have driven the production of 8 natural THCSpd, using single or mixed hydroxycinnamic acid precursors. Substrate promiscuities of 4CL and SHT were genuinely exploited to produce 8 new-to-nature THCSpd from exotic hydroxycinnamic and dihydrohydroxycinnamic acids, together with 3 new-to-nature THCSpd containing halogenated hydroxycinnamoyl moieties. In this work, we established a versatile and modular biotechnological production platform allowing the tailor-made THCSpd synthesis, constituting pioneer metabolic engineering for access to these valuable natural products.

Hydrolysis of bovine hemoglobin (bHb), the main constituent of bovine cruor by-product, releases a natural antimicrobial peptide (NKT) which could present a major interest for food safety. To enrich this, tangential ultrafiltration can be implemented, but ultrafiltration conditions are mainly empirically established. In this context, the application of a simulation method for predicting the NKT yield and enrichment was investigated. Ultrafiltration performances were studied for decolored bHb hydrolysates at different degrees of hydrolysis (DH, 3%, 5%, 10% and 18%) and colored hydrolysates (3% and 5% DH) with 1 and 3 kg&middot, mol&minus, 1 regenerated cellulose membranes. The simulation method helped to identify the most promising hydrolysate (in terms of NKT enrichment, yield and productivity) as the 3% DH colored hydrolysate, and UF conditions (volumetric reduction factor of 5 and 3 with 1 and 3 kg&middot, 1 membrane, respectively) for higher antimicrobial recovery. A maximal enrichment factor of about 29 and NKT purity of 70% in permeate were observed. The results showed that the antimicrobial activity was in relation with the process selectivity and NKT purity. Finally, this reliable method, applied for predicting the ultrafiltration performances to enrich peptides of interest, is part of a global approach to rationally valorize protein resources from various by-products.

Alternaria brassicicola causes black spot disease in Brassicaceae. During host infection, this necrotrophic fungus is exposed to various antimicrobial compounds, such as the phytoalexin brassinin which is produced by many cultivated Brassica species. To investigate the cellular mechanisms by which this compound causes toxicity and the corresponding fungal adaptive strategies, we first analyzed fungal transcriptional responses to short-term exposure to brassinin and then used additional functional approaches. This study supports the hypothesis that indolic phytoalexin primarily targets mitochondrial functions in fungal cells. Indeed, we notably observed that phytoalexin treatment of A. brassicicola disrupted the mitochondrial membrane potential and resulted in a significant and rapid decrease in the oxygen consumption rates. Secondary effects, such as Reactive oxygen species production, changes in lipid and endoplasmic reticulum homeostasis were then found to be induced. Consequently, the fungus has to adapt its metabolism to protect itself against the toxic effects of these molecules, especially via the activation of high osmolarity glycerol and cell wall integrity signaling pathways and by induction of the unfolded protein response.

International audience; Analysis of organic plastic additives (OPAs) associated to plastic polymers is growing. The current review outlines the characteristics and the development of (multi-step) pyrolysis coupled with a gas chromatography mass spectrometer (Py-GC/MS) for the identification and semi-quantification of OPAs. Compared to traditional methods, Py-GC/MS offers advantages like suppressing extensive steps of preparation, limiting contamination due to solvents and the possibility to analyse minute particles. Its key advantage is the successive analysis of OPAs and the polymeric matrix of the same sample. Based on the studied articles, numerous methods have been described allowing identification and, in some case, semi-quantification of OPAs. There is nevertheless no gold standard method, especially given the huge diversity of OPAs and the risks of interferences with polymers or other additives, but, among other parameters, a consensus temperature seems to arise from studies. More broadly, this review also explores many aspects on the sample preparation like weight and size of particles and calibration strategies. After studying the various works, some development prospects emerge and it appears that methodological developments should focus on better characterizing the limits of the methods in order to consider which OPAs can be quantified and in which polymers this is feasible.

International audience; Hybrid catalysis, which combines chemo- and biocatalytic benefits, is an efficient way to address green chemistry principles. 5-Hydroxymethylfurfural (HMF) is a versatile building block in numerous industrial applications. To date, few studies have described the production of its amine derivatives and their polymers. Finding a good methodology to directly transform HMF to 5-aminomethyl-2-furancarboxylic acid (AMFC) therefore represents an important challenge. After selecting the best oxidation catalyst for HMF conversion to 5-aldehyde-2-furancarboxylic acid and immobilizing a transaminase onto a solid carrier, we implemented the first one-pot/two-steps hybrid catalytic process to produce AMFC (77 % yield); this is the most efficient AMFC catalytic production method from HMF reported to date. This process also produced 2,5-furandicarboxylic acid (21 % yield) as a major secondary product that can be applied to polymer syntheses such as polyethylene furanoate. Herein, we report a novel way to access new biosourced polymers based on HMF oxidized and aminated derivatives.

National audience; La pollution plastique est une menace pour l’environnement et les organismes. Elle les expose à différents dangers. Un de ces dangers est l’impact chimique due aux additifs plastiques organiques. Différents types d’additifs peuvent être ajoutés au polymères plastiques au cours de leur formulation afin de leur conférer certaines propriétés. L’utilisation de certains additifs est controversée du fait que certaines molécules se sont révélées être toxique pour l’environnement, les organismes marins et l’homme. De ce fait, l’analyse des additifs plastiques montre un intérêt grandissant.Afin d’avoir une meilleure compréhension de l’impact chimique de ces additifs, il est important d’identifier, et idéalement quantifier les additifs inclus dans les matrices polymériques. Leur analyse dans les polymères est un challenge analytique du fait de la diversité de la composition chimiques des additifs et du fait qu’il soit, en général, en mélange au sein des polymères. De ce fait, développer des méthodes analytiques de screening relativement facile et rapide présente un réel intérêt. Le but de cette étude est de développer une méthode en pyrolyse couplée à une chromatographie gazeuse et spectrométrie de masse (Py-GC/MS) pour l’identification et, si possible, la quantification d’additifs plastiques organiques. Cette méthode permettra également de caractériser le type de polymère sur le même échantillon. La première étape a consisté à développer une méthode commune en GC/MS-Orbitrap pour l’analyse de différents additifs plastiques ainsi que de constituer une base de donnée haute résolution contenant une large variété d’additifs plastiques.

National audience; La recherche concernant les nano- (NP) et microplastiques (MP) s’est largement développée ces dernières années avec une meilleure connaissance de la façon dont les expérimentations doivent être conduites. Ainsi, il est désormais clair que ce sujet nécessite un investissement important en terme d’expertise, d’infrastructure, ou d’appareillage, de manière à garantir la production de résultats de qualité.Dans le cadre d’un contrat plan Etat/Région (CPER Marco), différents laboratoires du Boulonnais (Anses, LOG et ULCO) ont mis en place une plateforme (3PAC) de façon à partager leurs équipements analytiques, méthodes, expertises et connaissances.Parmi les infrastructures à disposition à l’heure actuelle sont retrouvés : des systèmes d’aquarium avec un environnement contrôlé pour réaliser des études d’exposition, une pièce « microplastique » permettant de réaliser des manipulations (digestion, filtration) sous atmosphère maîtrisée et ainsi limiter les risques de contamination. La caractérisation des particules (taille, forme) est ensuite réalisée à l’aide de divers équipements : une loupe binoculaire ou directement via l’utilisation du µ-Raman. Enfin l’identification des particules est rendue possible par l’utilisation de techniques spectroscopiques (µ-Raman) ou spectrométriques (Py-GC/MS et Py-GC/Orbitrap). L’acquisition de nouveaux équipements, complémentaires, est d’ores et déjà programmée de façon à venir enrichir les possibilités analytiques (microscopie confocale, µ-FT-IR, light scattering).Dès aujourd’hui, l’expertise des différents partenaires permet de couvrir un large champ de recherches allant des études en laboratoire, aux prélèvements sur le terrain. A titre d’exemple, des travaux récents ont porté sur l’étude de sédiments et organismes prélevés in situ, la réalisation d’études d’encagement d’organismes marins, ou encore l’exposition de bivalves en conditions contrôlées.L’ambition de la plateforme 3PAC est de répondre aux appels à projet nationaux et internationaux portant sur l’étude des particules plastiques et de leurs conséquences, en proposant un écosystème analytique idoine, regroupant expertises, technologies et infrastructures.

Vibrio bacteria, and particularly members of the Harveyi clade, are the causative agents of vibriosis, responsible for mass mortality events and importatn economic losses on aquaculture farms. Vibrio harveyi, which can form biofilms on aquaculture facility surfaces, has recently been identified as an emerging threat for seabass (Dicentrarchus labrax) aquaculture. As no prophylactic method is available on the market, it is urgent to improve surveillance and diagnosis tools to successfully manage vibriosis outbreaks. This thesis focuses on the optimisation of vibriosis risk reduction strategies in seabass farms, using a combination of microbiological and molecular approaches. First, we develop quantification and identification methods. A mreB-targeted SYBR Green I real-time PCR method was developed to quantify V. harveyi directly from environmental samples, including seawater and biofilms. A new in-house database named Luvibase, composed of 23 reference MALDI-TOF mass spectra profiles from vibrio collections strains, was elaborated in order to identify Vibrio species belonging to the Harveyi clade, by MALDI-TOF MS. Second, those methods were applied during a sampling campaign from April to October 2018 in a seabass aquaculture facility. Seawater and biofilm samples were collected from rearing tanks, and from the cold- and hot-water inlets, supplying the farm. The abundance of V. harveyi and Vibrionaceae cultivable at 37°C and their relative diversity were then determined. Several pathogens for seabass were constantly isolated during the sampling campaign. A positive correlation was highlighted between seawater temperature and their abundance in both types of samples. As these biofilms may act as a reservoir of V. harveyi in the farm, and as its abundance is likely to increase due to global warming, anti-biofilm solutions are urgently needed, in order to manage the risk of Vibrio outbreak.; Les bactéries du genre Vibrio et plus particulièrement celles du clade Harveyi, sont responsables de la vibriose, entraînant des mortalités de masse associées à des pertes économiques considérables pour le secteur aquacole. Vibrio Harveyi est un agent pathogène émergent pour le bar commun d'élevage (Dicentrarchus labrax), capable de former des biofilms. Etant donné qu'aucune méthode prophylactique n'est aujourd'hui commercialisée, la lutte contre la vibriose réside dans la prévention et le développement de méthodes de surveillance et de diagnostic. L'objectif de cette thèse consiste à apporter des éléments de compréhension, via la combinaison d'approches microbiologiques et moléculaires, visant à optimiser la gestion du risque Vibrio pour le bar commun d'élevage. Dans un premier temps, des méthodes de quantification et d'identification ont été mises au point. Une méthode de PCR en temps réel, ciblant le gène mreB, a été développée et optimisée pour quantifier V. harveyi à la fois dans l'eau et les biofilms. La "Luvibase", une base de données composée de 23 profils de spectres de masse de souches de Vibrio de collection a ensuite été élaborée, permettant d'identifier les espèces du clade Harveyi par MALDI-TOF MS. Dans un second temps, ces méthodes ont été appliquées lors d'une campagne hebdomadaire d'échantillonnage d'avril à octobre 2018 dans une ferme d'élevage de bars communs. Des échantillons d'eau et de biofilms ont été collectés à partir des bassins d'élevage et des arrivées d'eau chaude et froide, alimentant la ferme. L'abondance de V.harveyi et des Vibrionaceae cultivables à 37°C, mais aussi leur diversité relative ont ensuite été déterminées. Plusieurs espèces potentiellement pathogènes ont régulièrement été identifiées, dont V.harveyi, tout au long de la campagne. L'étude de l'influence des paramètres environnementaux a mis en évidence une corrélation positive entre la température de l'eau et l'abondance de ces bactéries à la fois dans l'eau et les biofilms. Sachant que ces biofilms peuvent induire une persistance de V.harveyi au sein de la ferme, et que leur abondance pourrait prochainement augmenter du fait du réchauffement climatique, il est urgent de développer des solutions anti-biofilms, afin de limiter le risque Vibrio.

On estime aujourd’hui que 90 % des procédés chimiques font appel à au moins un catalyseur, et que 30 à 40 % de l’économie mondiale dépendent directement ou indirectement de l’utilisation de catalyseurs. Ces espèces chimiques ou biologiques sont extrêmement répandues au niveau industriel ; elles permettent de mieux maitriser la sélectivité et la spécificité d’une grande diversité de réactions chimiques pour la formation à façon de composés cibles très variés, en jouant sur les chemins réactionnels et donc les énergies d’activations, tout en favorisant le plus souvent la cinétique. De manière générale, les catalyseurs sont le lieu d’environnements physicochimiques aux propriétés différentes de celles des milieux réactionnels conventionnels. Ils favorisent ou permettent des évènements réactionnels spécifiques (acte catalytique) mettant en œuvre leurs propriétés, et permettent même la création de nouveaux intermédiaires réactionnels facilitant et/ou orientant les réactions. La diversité des catalyseurs permet d’accéder à un panel extrêmement large de mécanismes moléculaires plus ou moins complexes dont la compréhension permet en retour un meilleur contrôle des réactions et l’optimisation de procédés catalytiques, ainsi que leur couplage raisonné selon des réactions dites « multi-catalytiques » qui tirent bénéfice des propriétés supplémentaires inédites de ces systèmes catalytiques ainsi assemblés. It is estimated today that 90% of chemical processes use less than one catalyst, and that 30-40% of the world economy depends directly or indirectly on the use of catalysts. These chemical or biological species are extremely widespread at the industrial level; they make it possible to better control the selectivity and specificity of a wide variety of chemical reactions for the customised formation of very varied target compounds, by playing on the reaction pathways and thus the activation energies, while most often favouring kinetics. In general, catalysts are the site of physicochemical environments with properties different from those of conventional reaction media. They promote or allow specific reaction events (catalytic act) implementing their properties, and even allow the creation of new reaction intermediates facilitating and/or directing reactions. The diversity of catalysts provides access to an extremely wide range of more or less complex molecular mechanisms, the understanding of which allowing for a better control of reactions and optimisation of catalytic processes, as well as their reasoned coupling according to so-called "multi-catalytic" reactions that benefit from the additional novel properties of these catalytic systems assembled in this way. 454

International audience; Le développement des légumineuses dans la sole française, facteur dedurabilité, doit faire face à des contraintes de production qui peuventpénaliser leur rentabilité. Des avancées significatives, obtenues en poisd’hiver, devraient accélérer le progrès génétique et favoriser cette culture.

International audience; The persistence of pathogenic Agrobacterium strains as soil-associated saprophytes may cause an inconsistency in the efficacy of the biocontrol inoculants under field condition. The study of the interaction occurring in the rhizosphere between the beneficial and the pathogenic microbes is thus interesting for the development of effective biopesticides for the management of crown gall disease. However, very little is still known about the influence of these complex interactions on the biocontrol determinants of beneficial bacteria, especially Bacillus strains. This study aimed to evaluate the effect of the soil borne pathogen Agrobacterium tumefaciens C58 on root colonization and lipopeptide production by Bacillus velezensis strain 32a during interaction with tomato plants. Results show that the presence of A. tumefaciens C58 positively impacted the root colonization level of the Bacillus strain. However, negative impact on surfactin production was observed in Agrobacterium-treated seedling, compared with control. Further investigation suggests that these modulations are due to a modified tomato root exudate composition during the tripartite interaction. Thus, this work contributes to enhance the knowledge on the impact of interspecies interaction on the ecological fitness of Bacillus cells living in the rhizosphere.

The aim of this study was to investigate the probiotic properties of 174 Lactobacillus strains isolated from Mongolian dairy products, and particularly their impact on intestinal calcium uptake and absorption. All isolates underwent a first screening based on cell surface hydrophobicity, acid tolerance, tolerance to gastro-intestinal digestion, autoaggregation, adhesion and cytotoxicity against intestinal cells. Six Lactobacillus strains from different species (L. casei, L. kefiranofaciens, L. plantarum, L. fermentum, L. helveticus and L. delbrueckii) were selected, and their impact on intestinal calcium uptake and transport was investigated using Caco-2. Five strains were able to improve total calcium transport after 24 h contact with a differentiated Caco-2 cell monolayer. Concomitantly the L. plantarum strain was able to increase cellular calcium uptake in Caco-2 cells by 10% in comparison to control conditions. To determine which pathway(s) of calcium absorption was modulated by the strains, a qPCR-based study on 4 genes related to calcium/vitamin D metabolism or tight junction integrity was conducted on mucus-secreting intestinal HT-29 MTX cells. The L. plantarum strain modulates the transcellular pathway by regulating the expression of vitamin D receptor (1.79 fold of control) and calcium transporter (4.77 fold of control) while the L. delbrueckii strain acts on the paracellular pathway by modulating claudin-2 expression (2.83 fold of control). This work highlights the impact of Lactobacillus probiotic strains on intestinal calcium absorption and for the first time give some evidence about the cellular pathways involved.

International audience

International audience; Ethnopharmacological relevance: An extensive ethnopharmacological survey was carried out in the Peruvian Amazonian district of Loreto with informants of various cultural origins from the surroundings of Iquitos (capital city of Loreto) and from 15 isolated riverine Quechua communities of the Pastaza River.A close attention was paid to the medical context and plant therapy, leading to the selection of 35 plant species (45 extracts). The extracts were tested for antiviral activity against HCV with counting of Huh-7 cellular death in case of toxicity, and cytotoxicity was evaluated in HepG2 cells.Aim of the study: The aim of the study was to inventory the plants used against hepatitis in Loreto, then to evaluate their antiviral activity and to suggest a way to improve local therapeutic strategy against viral hepatitis, which is a fatal disease that is still increasing in this area.Materials and methods: An ethnographic survey was carried out using “participant-observation” methodology and focusing on plant therapy against hepatitis including associated remedies. 45 parts of plant were extracted with methanol and tested in vitro for anti-HCV activity in 96-well plate, using HCV cell culture system with immunofluorescent detection assisted by automated confocal microscopy. Toxicity of plant extracts was also evaluated in microplates on hepatic cells by immunofluorescent detection, for the Huh-7 nuclei viability, and by UV-absorbance measurement of MTT formazan for cytotoxicity in HepG2 cells.Results: In vitro assay revealed interesting activity of 18 extracts (50% infection inhibition at 25 μg/mL) with low cytotoxicity for 15 of them. Result analysis showed that at least 30% of HCV virus were inhibited at 25 μg/mL for 60% of the plant extracts. Moreover, the ethnomedical survey showed that remedies used with low and accurate dosing as targeted therapy against hepatitis are usually more active than species indicated with more flexible dosing to alleviate symptoms of hepatic diseases.Conclusion: Together with bibliographic data analysis, this study supported the traditional medicinal uses of many plants and contributed to a better understanding of the local medical system. It also permitted to refine the therapeutic plant indications regarding patients’ liver injuries and vulnerability. Only 2 of the 15 most active plant species have already been studied for antiviral activity against hepatitis suggesting new avenues to be followed for the 13 other species.

International audience; The identification of non-fermentative Gram negative bacilli from run-off and spring water, including fluorescent Pseudomonas is very complex and investigations are needed to contribute to the systematic of these bacteria. In this dataset, the phenotypical profiles of three strains isolated from Vosges mountains first identified as Pseudomonas fluorescens were determined using APIⓇ 50 CH galleries. Then, the identification of their proteins released directly into water was carried out using tandem/mass spectrometry after separating proteins on native two-dimensional polyacrylamide gels. Finally, genotypic analysis data is presented, that illustrates biodiversity in this fluorescent bacterial group. This data is referred by a research article entitled "Fluorescent Pseudomonas strains from mid-mountain water able to release antioxidant proteins directly into water".

Biofilm bioreactors are promising systems for continuous biosurfactant production since they provide process stability through cell immobilization and avoid foam formation. In this work, a two-compartment biofilm bioreactor was designed consisting of a stirred tank reactor and a trickle-bed reactor containing a structured metal packing for biofilm formation. A strong and poor biofilm forming B. subtilis 168 strain due to restored exopolysaccharides (EPS) production or not were cultivated in the system to study the growth behavior of the planktonic and biofilm population for the establishment of a growth model. A high dilution rate was used in order to promote biofilm formation on the packing and wash out unwanted planktonic cells. Biofilm development kinetics on the packing were assessed through a total organic carbon mass balance. The EPS+ strain showed a significantly improved performance in terms of adhesion capacity and surfactin production. The mean surfactin productivity of the EPS+ strain was about 37% higher during the continuous cultivation compared to the EPS- strain. The substrate consumption together with the planktonic cell and biofilm development were properly predicted by the model (&alpha, = 0.05). The results show the efficiency of the biofilm bioreactor for continuous surfactin production using an EPS producing strain.

The physico-chemical, textural and color parameters and fluorescence spectra of aromatic amino acids and nucleic acids (AAA + NA), tryptophan residues, nicotinamide adenine dinucleotide (NADH) and vitamin A were scanned on sturgeon samples kept at 4 degrees C up to 12 days. Using the principal component analysis (PCA), the riboflavin and NADH spectra allowed clear differentiation between sturgeon samples according to their storage time. The best result was obtained by applying the common components and specific weights analysis (CCSWA) to the riboflavin and NADH data tables since better differentiation was achieved between the 4 group sturgeon samples aged: 2 days; 5, 6 and 7 days; 8 and 9 days and 12 days. The proposed methodology demonstrates the ability of CCSWA to evaluate sturgeon freshness level according to their storage time.

International audience; This study was performed on all Eryngium species growing in Tunisia in order to evaluate their intra and interspecies variabilities and to investigate their biological activities. These species are used in traditional medicine, and literature about the phytochemical investigations of most of them is scarce. Antimicrobial and light-enhanced activities were tested against multiresistant microorganisms and extended spectrum beta-lactamase producing bacteria (ESBL). All studied species showed antimicrobial effect with several MIC values lower than 70 μg/ml. Tested Eryngium species have proven to be a promising source of photoactive compounds, while light-enhanced activity offers an alternative for the inactivation of pathogenic microorganisms which is currently subjected to a great interest. This is the first report of this activity in genus Eryngium. A significant improvement of antimicrobial activity with UV irradiation was observed, mainly for E. dichotomum, E. ilicifolium and E. triquetrum. Cytotoxicity, studied for the first time for the most species, was evaluated against cancer (J774) and non-cancer (WI38) human cell lines. Chemical composition of volatile compounds presented in the most active crude extracts (petroleum ether extracts) of the aerial parts was investigated using GC/MS analysis and was submitted to statistical analyses. It revealed their high content of bioactive phytochemicals, particularly oxygenated sesquiterpenes like spathulenol, ledol and α-bisabolol but also hydrocarbon sesquiterpenes such as β-bisabolene and copaene, as well as polyacetylene derivatives such as falcarinol. Statistical analyses permitted to evaluate the interrelations between all Tunisian Eryngium species.

Polyurethanes (PU) are a family of versatile synthetic polymers intended for diverse applications. Biological degradation of PU is a blooming research domain as it contributes to the design of eco-friendly materials sensitive to biodegradation phenomena and the development of green recycling processes. In this field, an increasing number of studies deal with the discovery and characterization of enzymes and microorganisms able to degrade PU chains. The synthesis of short lifespan PU material sensitive to biological degradation is also of growing interest. Measurement of PU degradation can be performed by a wide range of analytical tools depending on the architecture of the materials and the biological entities. Recent developments of these analytical techniques allowed for a better understanding of the mechanisms involved in PU biodegradation. Here, we reviewed the evaluation of biological PU degradation, including the required analytics. Advantages, drawbacks, specific uses, and results of these analytics are largely discussed to provide a critical overview and support future studies.

Key messageThe spring wheat-derived QTLFhb1was successfully introgressed into triticale and resulted in significantly improved FHB resistance in the three triticale mapping populations.AbstractFusarium head blight (FHB) is a major problem in cereal production particularly because of mycotoxin contaminations. Here we characterized the resistance to FHB in triticale breeding material harboring resistance factors from bread wheat. A highly FHB-resistant experimental line which derives from a triticale × wheat cross was crossed to several modern triticale cultivars. Three populations of recombinant inbred lines were generated and evaluated in field experiments for FHB resistance using spray inoculations during four seasons and were genotyped with genotyping-by-sequencing and SSR markers. FHB severity was assessed in the field by visual scorings and on the harvested grain samples using digital picture analysis for quantifying the whitened kernel surface (WKS). Four QTLs with major effects on FHB resistance were identified, mapping to chromosomes 2B, 3B, 5R, and 7A. Those QTLs were detectable with bothFusariumseverity traits. Measuring of WKS allows easy and fast grain symptom quantification and appears as an effective scoring tool for FHB resistance. The QTL on 3B collocated withFhb1, and the QTL on 5R with the dwarfing geneDdw1. This is the first report demonstrating the successful introgression ofFhb1into triticale. It comprises a significant step forward for enhancing FHB resistance in this crop.

Plants are often subject to attack by fungi, nematodes and insects, which generate immense yield losses. Hence, the quest for crop protection solutions is ongoing, concurrent with greater awareness towards the use of synthetic chemicals in agricultural practice. Scientific research has shifted towards the use of natural products, which possess good efficacy and are environment friendly. This review details two classes of natural products. The first one is the plant essential oils with their volatile constituents, which have been proven to possess antifungal, nematicidal and insecticidal activities. The second class is the lipopeptides produced by antagonistic microorganisms. Their biological activities are discussed, as they have been shown effective against plant fungi and pests. Essential oils and lipopeptides have huge potential to be used as biopesticides. The combinatorial approach between essential oils, antagonistic microorganisms and lipopeptides for crop protection is discussed, potentially both can produce a synergistic effect, resulting from their combination against plant fungi, nematodes and pests.

Hybrid catalysis emerged about twenty years ago. This discipline aims at combining a chemical catalyst with a biological catalyst to produce a multi-catalytic system, with additional properties compared to those of single catalysts, has long remained little studied because it calls on a wide range of skills that are rarely brought together in joint work.In recent years, however, the growing interest in inter- or even transdisciplinary research has greatly benefited its development, and the number of examples of hybrid catalysis applications is now growing exponentially. Historically developed for kinetic resolution and deracemisation processes, hybrid catalysis is now illustrated in many fields, with very different purposes, from the regeneration of costly enzyme co-substrates to the implementation of integrated catalytic tandems allowing the synthesis of previously inaccessible compounds.In this respect, it benefits from numerous advances in chemistry and biology/molecular biology, whether in terms of new modelling or analytical techniques, the possibility of designing new, more efficient and tolerant catalysts, or the development of more efficient reaction devices thanks to reactor and process engineering. This important diversity of catalysts and techniques now represents a promising hope for the renewal of catalysis that is often struggling to meet tomorrow’s environmental challenges.; La catalyse hybride a émergé il y a une vingtaine d’années. Cette discipline, qui vise à combiner un catalyseur chimique avec un catalyseur biologique afin de produire un système multi-catalytique possédant des propriétés supplémentaires par rapport à celles des catalyseurs unitaires, est longtemps restée peu étudiée car faisant appel à des compétences très diversifiées rarement rassemblées au sein de travaux communs.Ces dernières années, l’accroissement de l’intérêt pour les recherches inter- voire transdisciplinaires a largement bénéficié à son développement et le nombre d’exemples d’applications de la catalyse hybride croît aujourd’hui de manière exponentielle. Historiquement mise au point pour les procédés de résolution cinétique et de déracémisation, elle s’illustre désormais dans de très nombreux domaines, avec des finalités très différentes, depuis la régénération de cosubstrats enzymatiques coûteux, jusqu’à la mise en place de tandems catalytiques intégrés permettant la synthèse de composés jusque-là inaccessibles.Elle bénéficie à ce titre de nombreuses avancées en chimie et biologie/biologie moléculaire, qu’il s’agisse des nouvelles techniques de modélisation ou analytiques, de la possibilité de concevoir de nouveaux catalyseurs plus efficaces et tolérants, ou encore de l’élaboration de dispositifs réactionnels plus performants grâce aux génies des réacteurs et des procédés. Cette importante diversité de catalyseurs et de techniques représente un espoir prometteur pour le renouveau d’une catalyse qui peine souvent à répondre aux défis environnementaux de demain.

International audience; In the recent years, research on microplastics (MP) and nanoplastics (NP) has largely developed with better insights on the way analyses have to be conducted. It is now clear that research in this topic necessitates huge investment in terms of expertise, infrastructure and materials in order to insure the best quality for results.In the framework of a French regional project, CPER Marco, different laboratories from Universities, CNRS and Anses decided to create a common platform (3PAC) in order to share knowledge, expertise, working methodologies and analysis devices. This platform presently gather different equipment: monitored laboratory aquaria for controlled exposition studies, a laminar flow cabinet to avoid contaminations, stereomicroscopes to characterize particles and a µRaman, a Py-GC/MS and a Py-GC/HRMS for the identification of polymers. In the future, acquisitions of new analytical equipment are planned including light scattering technology for NP characterization and µFT-IR for polymer identification. By now, expertise of the different partners allows to cover a large field of applications from both laboratory and field studies. Recently investigations have been carried out on sediment, organisms from the environment and their microbiote, but also caging of marine organisms, exposition of bivalves in controlled conditions. The ambition of 3PAC is to answer national and transnational call for projects, making available an ecosystem gathering expertise, technologies and infrastructures.

The heterogeneous catalytic partial oxidation of alcohols and aldehydes in the liquid phase usually needs the addition of a homogeneous base, which in turn makes the products&rsquo, recovery cumbersome, and can further induce undesired side reactions. In the present work, we propose the use of novel catalysts based on metallic Au, Pd and bimetallic AuPd nanoparticles embedded in a titanosilicate matrix. The as-prepared catalysts showed good efficiency in the base-free partial oxidation of furfural and 5-hydroxymethylfurfural. Au4Pd1@SiTi catalyst showed high selectivity (78%) to monoacids (namely, 5-formyl-2-furancarboxylic acid and 5-hydroxymethyl-2-furancarboxylic acid) at 50% 5-hydroxymethylfurfural (HMF) conversion. The selectivity even reached 83% in the case of furfural oxidation to furoic acid (at 50% furfural conversion). The performances of the catalysts strongly depended on the Au&ndash, Pd ratio, with an optimal value of 4:1. The pH of the solution was always below 3.5 and no leaching of metals was observed, confirming the stabilization of the metal nanoparticles within the titanosilicate host matrix.

The effectiveness of chemical as well as biological catalysts for carrying out chemical reactions on an industrial level is no longer to be demonstrated. Their specificity and selectivity make them essential tools for many processes, and as such, they represent a major key in the establishment of tomorrow's industry. Historically, catalysts have mostly been used in a unitary manner, with processes involving several catalysts most often forming part of multi-stage strategies. However, the last two decades have seen a significant increase in research into multi-catalytic reactions that combine two or more catalysts in order to benefit from collaborative effects. While catalysts of different natures are very rarely used together, the combination of a chemical catalyst and a biocatalyst, known as "hybrid catalysis", is most likely the most promising type of multi-catalytic reaction because of the unprecedented diversity and efficiency allowed. Nevertheless, it remains the most complex to implement, calling on skills from different fields (chemistry, biology, materials, etc.). The prospects it offers are giving riseto pioneering work that is pushing researchers to develop new strategies for overcoming the limitations and inhibitions that inevitably arise when these two types of catalyst are forced to work together.; L’efficacité des catalyseurs chimiques et biologiques pour la réalisation de réactions chimiques au niveau industriel n’est plus à démontrer. Leur spécificité et sélectivité en font des outils essentiels à de nombreux procédés, et ils représentent à ce titre un outil majeur dans l’établissement de l’industrie de demain.Historiquement, les catalyseurs ont été très majoritairement utilisés de manière unitaire, les procédés en faisant intervenir plusieurs s’inscrivant le plus souvent dans des stratégies multi-étapes. Cependant, les deux dernières décennies ont vu un essor de la recherche autour des réactions multi-catalytiques qui combinent deux catalyseurs ou plus afin de bénéficier d’effets collaSi des catalyseurs de natures différentes ne sont que très rarement mis en jeu ensemble, la combinaison d’un catalyseur chimique et d’un biocatalyseur, appelée « catalyse hybride », représente très probablement le type de réaction multi-catalytique le plus prometteur de par la diversité et l’efficacité inédites permises. Elle n’en demeure pas moins la plus complexe à mettre en œuvre, faisant appel à des compétences de domaines différents (chimie, biologie, matériaux, etc.). Les perspectives offertes donnent lieu à des travaux pionniers qui poussent les chercheurs à mettre au point de nouvelles stratégies permettant de contourner les limitations et inhibitions qui ne manquent pas d’apparaitre lorsque l’on force ces deux types de catalyseurs à travailler de concert.

Enterococci are opportunistic pathogens responsible for hospital- and community-acquired infections. All enterococci produce a surface polysaccharide called EPA (enterococcal polysaccharide antigen) required for biofilm formation, antibiotic resistance, and pathogenesis. Despite the critical role of EPA in cell growth and division and as a major virulence factor, no information is available on its structure. Here, we report the complete structure of the EPA polymer produced by the model strain E. faecalis V583. We describe the structure of the EPA backbone, made of a rhamnan hexasaccharide substituted by Glc and GlcNAc residues, and show that teichoic acids are covalently bound to this rhamnan chain, forming the so-called “EPA decorations” essential for host colonization and pathogenesis. This report represents a key step in efforts to identify the structural properties of EPA that are essential for its biological activity and to identify novel targets to develop preventive and therapeutic approaches against enterococci., All enterococci produce a complex polysaccharide called the enterococcal polysaccharide antigen (EPA). This polymer is required for normal cell growth and division and for resistance to cephalosporins and plays a critical role in host-pathogen interaction. The EPA contributes to host colonization and is essential for virulence, conferring resistance to phagocytosis during the infection. Recent studies revealed that the “decorations” of the EPA polymer, encoded by genetic loci that are variable between isolates, underpin the biological activity of this surface polysaccharide. In this work, we investigated the structure of the EPA polymer produced by the high-risk enterococcal clonal complex Enterococcus faecalis V583. We analyzed purified EPA from the wild-type strain and a mutant lacking decorations and elucidated the structure of the EPA backbone and decorations. We showed that the rhamnan backbone of EPA is composed of a hexasaccharide repeat unit of C2- and C3-linked rhamnan chains, partially substituted in the C3 position by α-glucose (α-Glc) and in the C2 position by β-N-acetylglucosamine (β-GlcNAc). The so-called “EPA decorations” consist of phosphopolysaccharide chains corresponding to teichoic acids covalently bound to the rhamnan backbone. The elucidation of the complete EPA structure allowed us to propose a biosynthetic pathway, a first essential step toward the design of antimicrobials targeting the synthesis of this virulence factor.

International audience; Freezing is a major environmental limitation that affects biomass and seed productivity in a large number of crop species including legumes. Medicago truncatula is a model molecular‐genetic system for legume biology. A strategy to decipher freezing tolerance after a cold acclimation period in M. truncatula was developed using a quantitative genetic approach. Three main quantitative trait loci (QTL) with additive effects for freezing damage were detected on chromosomes 1, 4, and 6 using a recombinant inbred line population derived from a cross between the freezing‐tolerant accession F83005‐5 and the freezing‐sensitive accession DZA045‐5. The QTL on chromosome 6, named Mt‐FTQTL6, explained 40% of the phenotypic variance. Fine mapping of Mt‐FTQTL6 led to the identification of 20 positional candidate genes. Twelve of these 20 genes belong to the C‐repeat binding factor/dehydration‐responsive element binding factor 1 group of the AP2/EREBP transcription factor family and are tandemly arrayed. Non‐synonymous single nucleotide polymorphism (SNP) mutations, indels, and copy number variations were identified as putative candidate polymorphisms in CBF/DREB1 genes to explain the difference in freezing tolerance between the parental M. truncatula accessions. These important findings pave the way for translational applications to improve freezing tolerance in crop legumes such as pea, lentil, faba bean, and alfalfa

Population genetic structure of the worldwide-distributed wheat pathogen Zymoseptoria tritici has been extensively studied at large geographical scales, but to a much less extent at small or local spatial scales. A total of 627 single-conidial fungal isolates were sampled from several locations in northern France (Hauts-de-France Region) to assess fungal genetic structure at region, field, plant, and leaf layer scales, using highly polymorphic microsatellite markers and mating type idiomorphs. Important and overall similar levels of both gene and genotype diversities (gene diversity values of ≥0.44 and haplotype frequencies of ≥94%) were found at all the examined scales. Such rates of diversity are likely due to an active sexual recombination in the investigated areas, as revealed by equal proportions of the two mating types scored in all sampled populations. Interestingly, a rare occurrence of clones among lesions from a same leaf, as well as among leaves from different plant leaf layers (e.g., upper versus lower leaves), was highlighted, indicating that ascospores contribute much more than expected to Z. tritici epidemics, compared with pycnidiospores. Population structure and analyses of molecular variance revealed significant genetic differentiation at the regional scale (GST = 0.23) and, as expected, not at the other more local scales (GST ≤ 0.01). Further analyses using Bayesian and unweighted neighbor-joining statistical methods detected six genetic clusters within the regional population, overall distributed according to the locations from which the isolates were sampled. Neither clear directional relative migration linked to the geographical distribution of the locations, nor isolation by distance, were observed. Separate evolutionary trajectories caused by selection and adaptations to habitat heterogeneity could be the main forces shaping such structuration. This study provides new insights into the epidemiology and the genetic structure of Z. tritici at small local and, for the first time, at single plant and leaf layer scales. Such findings would be helpful in implementing effective control strategies.

International audience; Flax (Linum usitatissimum) is a plant grown in temperate regions either for its fiber or for its seeds, which are rich in the essential fatty acid omega-3. It is also well known as a source of medicinal compounds. The chemical composition of its leaves is currently poorly described. In order to fill this gap, we have conducted a comprehensive analysis of flax leaf metabolome. The exploration of the metabolome allowed the characterization of compounds isolated for the first time in flax leaves. These molecules were isolated by preparative HPLC and then characterized by NMR, LC-MS and standard analysis. This work extended our picture of C-glycosyl-flavonoids and coniferyl alcohol derivatives accumulated in flax. The follow-up of the content of these different metabolites via UPLC-MS revealed significant accumulation differences in spring and winter flax leaves. In particular, two methylated C-glycosylflavonoids (swertisin and swertiajaponin) were the most abundant phenolic compounds in winter flax whereas they were not detected in spring flax. This result suggests that these 2 compounds are involved in cold stress tolerance in flax.

To support small and large-scale genome mining projects, we present Post-processing Analysis tooLbox for ANTIsmash Reports (Palantir), a dedicated software suite for handling and refining secondary metabolite biosynthetic gene cluster (BGC) data annotated with the popular antiSMASH pipeline. Palantir provides new functionalities building on NRPS/PKS predictions from antiSMASH, such as improved BGC annotation, module delineation and easy access to sub-sequences at different levels (cluster, gene, module and domain). Moreover, it can parse user-provided antiSMASH reports and reformat them for direct use or storage in a relational database.Palantir is released both as a Perl API available on CPAN (https://metacpan.org/release/Bio-Palantir) and as a web application (http://palantir.uliege.be). As a practical use case, the web interface also features a database built from the mining of 1616 cyanobacterial genomes, of which 1488 were predicted to encode at least one BGC.Supplementary data are available at Bioinformatics online.

International audience