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Image Analysis and Untargeted Metabolomics Reveal Potential Phytotoxins from Fusarium venenatum Against Major Parasitic Weed Phelipanche ramosa (L.) Pomel
No full textInternational audienceBranched broomrape (Phelipanche ramosa (L.) Pomel), an obligate parasitic weed with a wide host range, is known for its devasting effects on many crops worldwide. Soil fungi, notably Fusarium sp., are described as pathogenic to broomrape, while the hypothesis of the phytotoxicity of fusaric acid produced by F. verticillioides for parasitic weeds of the genus Orobanche has been proposed. Using image analysis and untargeted metabolomics, this study investigated fungal metabolites phytotoxic for P. ramosa and produced by the F. venenatum MIAE02836 strain, isolated from symptomatic broomrapes and identified as a promising candidate for broomrape biocontrol. Phytotoxicity tests of crude extracts from the fungus alone or in interaction with broomrape on P. ramosa microcalli and quantification of necrosis by image analysis confirmed the phytotoxic potential of F. venenatum MIAE02836 metabolites towards the early developmental stages of P. ramosa. Data analysis of a non-targeted metabolomics approach revealed numerous metabolites produced by F. venenatum MIAE02836. Four of them, accumulated during interaction with the parasitic plant, are known for their phytotoxic potential: maculosin, cyclo(Leu-Phe), phenylalanyl-D-histidine and anguidine. These results suggest that combining image acquisition of the microcalli screening test and untargeted metabolomic approach is an interesting and relevant method to characterize phytotoxic fungal metabolites
Municipal efficiency spillovers in France
No full textInternational audienceThis paper provides evidence of the role of efficiency spillovers between French municipalities assessed through four levels of municipal equipment. We investigate changes in municipal efficiency for both cities possessing a certain level of public goods and cities located closer to those hosting high-rank functions. Based on a cross-sectional database pertaining to French municipalities with over 3500 inhabitants in 2018, we develop a two-stage approach. In the first stage, we estimate municipal efficiency through a robust order- m approach, while in the second stage, we run a truncated bootstrapped regression to disentangle the effect of the distance of an observed municipality to each of the four equipment levels. Our results provide evidence of efficiency spillovers where the less-endowed municipalities benefit the most from higher efficiency due to their geographical proximity to larger equipment centers
Diverse impact of topography and cultivation location on the polyphenolic profiles and certain sensory attributes of ‘País’ heritage wines from the Maule dryland region (Chile)
No full textInternational audiencePolyphenols are compounds that have traditionally been related to sensory properties of wines. The synthesis of these secondary metabolites can be influenced by numerous factors, including the edaphoclimatic conditions of the growing area of vines. In this study, the effect of topography and cultivation location on the chemical composition and sensory perception of wines was determined. Different vineyards cultivating the 'Pais' grape variety were selected. This variety is of great historical heritage relevance in collections of different wineproducing countries. Three vine growing areas from each of three localities of a dryland region of Chile displaying either "Hilly" (slope 18-20 %) or "Valley" (slope less than 9 %) topographies were selected. Resulting wines were analyzed chemically (spectrophotometry and HPLC-DAD) and sensorially (acceptability and CATA). A close relationship between edaphoclimatic conditions of the vine growing area and certain sensory properties of wines (color, mouthfeel but not aroma) was evidenced. By contrast, association between edaphoclimatic conditions of vine cultivation and the phenolic profile of the wine products was unclear. Furthermore, phenolic differences between the wines produced from vines grown at different topographical conditions were not significant
Hazard assessment of fenozan, a released non-intentionally added substance from polyester-based can coating
No full textInternational audienceSince the safety of new-generation polyester-based internal coatings regarding the migration of non-intentionally added substances (NIAS) is poorly documented, studies are needed to identify NIAS originating from these food-contact materials (FCM). The aim of this study was to identify volatile and semi-volatile NIAS from polyester-based coatings in order to assess their hazard and ensure consumers’ safety with regard to exposure from canned food. Extraction and migration tests were carried out on a single polyester-coated tin plate (5 batches) using two solvents: acetonitrile and ethanol 95%, then FCM’s extracts and migrates were analysed by GC-MS. An antioxidant degradation (hydrolysis) product, 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionic acid or fenozan (CAS RN: 20170-32-5), was identified and confirmed by reference standard in all migrates. To assess fenozan’s toxicity, several in vitro bioassays, such as the Ames test (to assess point mutation), the micronucleus assay (to detect chromosomal aberrations), and the iodide uptake assay (to study one mode of action for thyroid disruption) were conducted. Fenozan was negative in the Ames test on three strains of S. typhimurium (TA98, TA100, and TA1535) and on one strain of E.coli (WP2), with and without metabolic activation system (S9 mix) using direct incorporation and pre-incubation methods. The in vitro micronucleus assay conducted on HepG2 cells also exhibited a negative response following a 4-hour treatment with the S9 mix, and a 48-hour treatment without the S9 mix. A weak inhibitory effect was obtained when testing fenozan in the iodide uptake assay using rat thyroid FRTL-5 cells. Significant inhibition started from 800 µM of fenozan, with a maximal inhibition of almost 47% at 1000 µM. The findings indicate that fenozan exhibits an anti-thyroid activity in vitro
Getting fit for climate change : modelling future crop-weed interactions in French arable cropping systems
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Resumption of the planting of grapevine varieties in France, referred to as "disease-resistant"
No full textInternational audienceThis article investigates the beginning of the adoption of a new generation of “resistant” grapevine varieties (RVs) in France, in a European context in which varietal innovation has become more and more dynamic over the last thirty years.Today, there is a growing interest in this plant material, because it constitutes a lever for adaptation to the combined impacts of climate change and fungal diseases in vineyards. Based on data from the French digital vineyard register (CVI: “casier viticole informatisé”), this paper provides RV maps of leading regions, as well as less involved ones, which show the implantation of these varieties
Adapting agricultural production systems to changes in the environmental, agricultural and social context, and the role of legumes in the agro-ecological transition
No full textThis issue brings together texts from projects carried out as part of the PSDR 4 Programme, under the aegis of INRAE and 10 French RegionsInternational audienceIn the Burgundy Franche-Comté and Auvergne-Rhône-Alpes French regions, the regional projects POEETE and ProSys dealt with the adaptation of agricultural production systems to changes in the environmental, agricultural and social context, focusing on different scales and taking into account the context of reduced inputs and the search for autonomy by introducing legume crops. The processed data come from various approaches: surveys, experimental monitoring, modelling approach... The impact of climate change on the ecophysiology of legume crops was addressed through a model plant, the pea, and two criteria: flowering date and frost stress. To ensure the sustainability of mixed farming operations, new forage mixtures have been tested. Then the ecosystemic services provided by legume crops were studied: precedent effect, nitrogen content and interest in improving the protein autonomy of farms. The prioritization of ecosystem services in the adoption of these crops was studied via surveys of pioneer farmers in the region. Finally, the agroecological transition was studied via questions about the complementarity of mixed farming and livestock production, the performance of cropping systems including legume crops, farmers' motivations to develop more agro-ecological practices and the study of model farm trajectories
Les mots-clés des curricula
No full textInternational audienceQu’est-ce qu’un curriculum d’éducation ou de formation ? Quels sont leurs liens avec des programmes, plans d’études, référentiels ? Quels sont leurs composants, leurs contenus, leurs modalités de mise en œuvre et leurs évaluations ? Quelles sont leurs relations avec les disciplines, les éducations à… et les dispositifs ? Comment sont-ils élaborés ? Quelles sont leurs morphologies ? Comment sont-ils pris en charge et utilisés par les acteurs ?Voici différentes questions traitées dans cet ouvrage qui regroupe des textes inédits de 24 universitaires qui ont accepté de fédérer leurs travaux de recherche sur les curricula. Ils sont issus de 14 établissements universitaires de l’espace francophone. Cette double diversité de spécialité et de situation géographique assure à cet ouvrage l’équilibre nécessaire à la compréhension des curricula, la rigueur scientifique des écrits le préservant aussi de tout penchant doctrinaire ou militant. Il vise l’appropriation des concepts, des problématiques de recherche et des méthodologies d’investigation des curricula en portant une attention privilégiée aux contenus, tout en croisant cette perspective didactique avec des points de vue sociologiques, historiques, politiques et anthropologiques.Dans un contexte où les sociétés occidentales sont bousculées dans leurs certitudes venues d’un autre temps, aussi bien par les innovations technologiques que par leurs évolutions internes, Les mots-clés des curricula met à la disposition d’un lectorat varié (étudiants, enseignants, chercheurs, responsables politiques, citoyens) une présentation claire d’un large éventail des éléments qui constituent les curricula et qui permettent d’en comprendre la complexité et les conditions de leur conception et opérationnalisation
Evaluating the biomolecular interaction between delamanid/formulations and human serum albumin by fluorescence, CD spectroscopy and SPR: Effects on protein conformation, kinetic and thermodynamic parameters
No full textCorresponding author: [email protected] (T. Srichana).International audienceDelamanid is an anti-tuberculosis drug used for the treatment of drug-resistant tuberculosis. Since delamanid has a high protein bound potential, even patients with low albumin levels should experience high and rapid delamanid clearance. However, the interaction between delamanid and albumin should be better controlled to optimize drug efficacy. This study was designed to evaluate the binding characteristics of delamanid to human serum albumin (HSA) using various methods: fluorescence spectroscopy, circular dichroism (CD), surface plasmon resonance (SPR), and molecular docking simulation. The fluorescence emission band without any shift indicated the interaction was not affected by the polarity of the fluorophore microenvironment. The reduction of fluorescence intensity at 344 nm was proportional to the increment of delamanid concentration as a fluorescence quencher. UV-absorbance measurement at the maximum wavelength (λmax, 280 nm) was evaluated using inner filter effect correction. The HSA conformation change was explained by the intermolecular energy transfer between delamanid and HSA during complex formation. The study, which was conducted at temperatures of 298 K, 303 K, and 310 K, revealed a static quenching mechanism that correlated with a decreased of bimolecular quenching rate constant (kq) and binding constant (Ka) at increased temperatures. The Ka was 1.75–3.16 × 104 M−1 with a specific binding site with stoichiometry 1:1. The negative enthalpy change, negative entropy change, and negative Gibbs free energy change demonstrated an exothermic-spontaneous reaction while van der Waals forces and hydrogen bonds played a vital role in the binding. The molecular displacement approach and molecular docking confirmed that the binding occurred mainly in subdomain IIA, which is a hydrophobic pocket of HSA, with a theoretical binding free energy of −9.33 kcal/mol. SPR exhibited a real time negative sensorgram that resulted from deviation of the reflex angle due to ligand delamanid-HSA complex forming. The binding occurred spontaneously after delamanid was presented to the HSA surface. The SPR mathematical fitting model revealed that the association rate constant (kon) was 2.62 × 108 s−1M−1 and the dissociation rate constant (koff) was 5.65 × 10−3 s−1. The complexes were performed with an association constant (KA) of 4.64 × 1010 M−1 and the dissociation constant (KD) of 2.15 × 10−11 M. The binding constant indicated high binding affinity and high stability of the complex in an equilibrium. Modified CD spectra revealed that conformation of the HSA structure was altered by the presence of delamanid during preparation of the proliposomes that led to the reduction of secondary structure stabilization. This was indicated by the percentage decrease of α-helix. These findings are beneficial to understanding delamanid-HSA binding characteristics as well as the drug administration regimen
Actualisation des repères du PNNS : répartition temporelle des prises alimentaires
No full textCitation suggérée : Anses. (2024). Actualisation des repères du PNNS : répartition temporelle des prises alimentaires. (Saisine 2019-SA-0001). Maisons-Alfort : Anses, 202 p.A la demande de la Direction générale de la santé, l’Anses a élaboré en 2016 le fonds scientifique nécessaire à la formulation des repères alimentaires dans le cadre de l’actualisation du Plan national nutrition santé (Anses 2016b). Ce travail scientifique de fond a permis l’élaboration de repères semi-quantitatifs de consommation des groupes d’aliments.Au cours de ces travaux, les discussions collectives entre experts et les échanges avec les parties prenantes ont fait émerger la question de la pertinence de recommandations portant sur la répartition des prises alimentaires dans la journée