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Le paludisme apparaît comme la plus vieille et la plus meurtrière des maladies tropicales. A travers le monde, de nombreux peuples ont utilisé traditionnellement des plantes pour lutter contre cette maladie. Pour contribuer à la lutte préventive contre le paludisme, une enquête ethnobotanique a été menée à Niamey au près des 40 tradipraticiens afin inventorier les plantes spontanées présumées avoir des activités insecticides. Il ressort des résultats de cette enquête, une nette prédominance des hommes dans l’exercice de la médecine traditionnelle au Niger. En effet, sur les 40 tradipraticiens enquêtés, 36 sont des hommes contre seulement 4 femmes. L’enquête a permis de recenser 28 espèces végétales potentiellement insecticides. Ces plantes sont reparties dans plusieurs familles, celles les plus représentatives sont les Papilionaceae (21,4%), les Lamiaceae (7,1%), les Euphorbiaceae (7,1%), les Combretaceae (7,1%) et les Capparidaceae (7,1%). Les plantes fréquemment citées sont: Azadirachta indica (21%), Striga hermontheca (13,9%) et Hyptis spicigera (10,0%). Les parties des plantes les plus utilisées sont principalement les feuilles (53,3%) et les tiges feuillées (33,3%), avec comme mode principal d’utilisation la fumigation (82,0%). Ces résultats pourraient servir dans le domaine de la recherche des nouveaux biopesticides. L’investigation sera étendue à d’autres régions du pays afin de rassembler le maximum d’espèces végétales antipaludiques. Mots clés: Enquête ethnobotanique, tradipraticiens, plantes insecticides, moustiques, paludisme. English title: Ethnobotanical survey on plants traditionally used in Niger in the fight against mosquitoes vectors of parasitic diseases Malaria appears to be the oldest and deadliest tropical disease. Throughout the world, many people have traditionally used plants to fight this disease. To contribute to the preventive fight against malaria, an ethnobotanical survey has been carried out in Niamey with traditional practitioners to inventory spontaneous plants presumed to have insecticidal activities. The survey shows a predominance of men in the sector; thus, of the 40 traditional healers surveyed, we have 36 men and 4 women. The survey identified 28 potentially insecticidal plant species. These plants are distributed in several families, the most representative are Papilionaceae (21.4%), Lamiaceae (7.1%), Euphorbiaceae (7.1%), Combretaceae (7.1%) and Capparidaceae (7.1%). The most frequently mentioned plants are: Azadirachta indica (21%), Striga hermontheca (13.9%) and Hyptis spicigera (10.0%). The most commonly used plant parts are mainly leaves (53.3%) and leafy stems (33.3%), with fumigation as the main mode of use (82.0%). These results could be used in the field of research of new biopesticides. The investigation will be extended to other regions of the country to gather the maximum number of plant antimalarial species. Keywords: Ethnobotanical survey, traditional healers, medicinal plants, mosquitoes, malaria.

This study aimed to investigate the antiulcer and antioxidant activities of myrtle berry seed aqueous extract (MBSAE) in a peptic ulcer model induced by ethanol in male Wistar rats. MBSAE is rich in total polyphenols, total flavonoids, and unsaturated fatty acids, particularly linoleic (18:2) and oleic (18:1) acids. MBSAE also exhibited in vitro antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) (IC50= 172.1 μg/mL) and superoxide anion (IC50= 200.24 μg/mL) scavenging activities. In vivo, MBSAE provided dose-dependent protection against ethanol-induced gastric and duodenal macroscopic and histological alterations. Also, it inhibited secretory profile disturbances and lipid peroxidation, and preserved normal antioxidant enzyme activities and nonenzymatic antioxidant levels. More importantly, we showed that acute alcohol intoxication increased gastric and duodenal calcium, hydrogen peroxide, and free iron levels, whereas MBSAE treatment protected against intracellular mediator deregulation. In conclusion, we suggest that MBSAE has potent protective effects against alcohol-induced peptic ulcer in rat. This protection might be related in part to its antioxidant properties as well as its opposite effects on some studied intracellular mediators.

Changes in fatty acid profile, lipid quality, essential oil composition, total phenolic (TPC) and flavonoid (TFC) contents, radical scavenging, antibacterial and insecticidal activities were studied during the maturation of Schinus terebinthifolius Raddi fruits. Total lipids showed their maximum at the earlier and intermediate stage (green and half-red) of maturation, whereas, the highest levels of the main components linoleic and oleic acids were found at the late stage (red). Mature fruits were also distinguished by their high lipid quality as revealed by the lower values of n-3/n-6 ratio, calculated oxidizability (Cox), oxidative susceptibility (OS), atherogenic index (AI) and thromobogenic index (TI). The contents of monoterpenes decreased while those of sesquiterpenes increased during maturation. With the exception of α-pinene which dropped remarkably from immature to mature fruits, the content of the other main components (α-phellandrene, β-phellandrene and limonene) showed irregular variations. The TPC in intact and hydrodistilled fruits was higher at the last stage of maturation, while the maximum of TFC was recorded in the intermediate stage. Concomitantly, extract from residual hydrodistilled fruits was found as the most potent radical scavengers, whereas, the oils were found as the least scavengers. Nevertheless, they showed an appreciable antibacterial activity against Enterococcus feacium and Streptococcus agalactiae and exert a strong insecticidal activity against Spodoptera littoralis and Phthorimaea operculella . Collectively, these results suggest that the fruits of S. terebinthifolius could be considered as consolidated source of lipid and essential fatty acids, which may provide some health benefits to consumers. They also showed that the essential oils of S. terebinthifolius fruits can potentially be used in S. littoralis and P. operculella control in association with integrated pest management practices. Moreover, the use of extracts from intact or hydrodistilled residual fruits for the development of functional ingredients and the production of bio-based preservatives is encouraged.

International audience; In the present study, the effect of Ecbalium elaterium seed oil on adhesion, migration and proliferation of human brain cancer cell line (U87) was determined. Treatment of U87 cell line with the seed oil resulted in strong inhibition of their adhesion to fibrinogen (Fg), fibronectin (Fn). It also reduced their migration and proliferation in a dose-dependent manner without being cytotoxic. Concomitantly, by using Matrigel™ assays, the oil significantly inhibited angiogenesis. The anti- tumor effect of the oil is specifically mediated by αvβ3 and α5β1 integrins. The presence of integrin antagonists in seed oil from E. elaterium could be used for the development of anticancer drugs with targeted "multi-modal" therapies combining anti-adhesif, antiproliferative, antimetastasic and anti-angiogenic, approaches.

International audience; In the present work, we propose the synthesis of a new family of sugar derived 1,4:3,6-dianhydrohexitol based AA/AB-type monomers. Unprecedented diacids based on Isomannide and Isoidide were elaborated with high yields and showed interestingly high melting point ranges (240-375 degrees C). Optimization of reaction conditions (temperature, time of reaction, and reactant ratios) has been investigated to synthesize the key intermediate of a set of AB monomers with acid, ester, and acid chloride functionalities. Isosorbide based ether benzoic acid AB monomer was polymerized and characterized by NMR and DSC techniques. The results show a semicrystalline behavior of the obtained polymer thanks to the controlled stereoregular arrangement of the AB starting monomer.

Enzyme-assisted extraction has emerged as an attractive green, cost-effective and high bioactive yielding technology by which desired bioactives with preserved or better efficacy are released. In the present study, the ability of cellulase, hemicellulase and their binary mixture (cellulase:hemicellulase; 1:1) in improving the extraction of essential oils from coriander (Coriandrum sativum L.) seeds, or the residue by-products from the distillation process containing value-added phytochemicals (fatty acids and phenolics) were evaluated. Cellulase and the binary mixture improved the extraction of essential oils by 44.2 and 40%, respectively. Application of enzymes was associated with increased amount of oxygenated terpenes in the essential oils derived from enzyme-treated samples. Linalool, camphor and geranyl acetate were the prominent compounds. From the hydrodistillation residues, a better recovery of petroselinic-rich oil with a good nutritional quality was also observed in enzyme-treated seeds. They also contained an appreciable amount of polyphenols and showed an improved antioxidant activity as revealed by the DPPH, FRAP and cellular antioxidant activity assays. The results suggested that enzyme pre-treatment allowed better recovery without alteration of the essential oil composition. The hydrodistillation residues obtained could be potentially exploited for the development of functional food ingredients and nutraceuticals.

International audience; The fatty acid, essential oil compositions and their respective antioxidant and antibacterial activities was determined in Schinus terebinthifolius Raddi leaves and twigs. The lipid content ranged from 1.75 to 4.65% in twigs and leaves, respectively. Thirteen fatty acids were identified with α-linolenic (C18:3), palmitic (C16:0) and linoleic (C18:2) acids being the main components. The essential oils of both organs were characterized by a high amount of monoterpene hydrocarbons (68.91-74.88%) with α-phellandrene (33.06-36.18%), α-pinene (14.85-15.18%) and limonene (6.62-8.79%) being the chief components. The DPPH˙ radical scavenging assay revealed that both oils have a very weak antiradical activity. In contrast, they showed an appreciable antibacterial activity against the gram-positive Enterococcus feacium (ATCC 19434) and Streptococcus agalactiae (ATCC 13813) bacteria. These results suggest that leaves and twigs of S. terebinthifolius could be considered as an important dietary source of health promoting phytochemicals and has a good potential for use in food industry and pharmacy.

International audience; Bay leaves (Laurus nobilis L.) are widely used as a condiment and their therapeutic benefits are well known. These biological properties were attributed to a plethora of highly bioactive secondary metabolites namely essential oils and phenolics. However, their recovery from plant matrix is generally limited by the presence of physical barrier (cell wall). Thus, the use of novel extraction procedures to enhance their release is particularly important. Therefore, the aim of this work is to assess the potential use of enzyme treatment (cellulase, hemicellulase, xylanase end the ternary mixture of them) as a tool to improve the extraction efficiency of bioactive compounds from bay leaves. Results showed that enzyme pre-treatment resulted in 243, 227, 240.54 and 0.48% increase in the essential oil yields in samples treated with cellulase, hemicellulase, xylanase and the ternary mixture, respectively. Compositional analysis by GC and GC MS revealed remarkable enrichment of the essential oils derived from enzyme-treated samples with oxygenated monoterpenes, leading hence to better antioxidant activity as revealed by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and azino-bis-(3-ethylbenzothiolzoline 6-sulphonic acid) (ABTS) assays. The 1,8-cineole, alpha-terpinyl acetate, methyl eugenol, linalool, a-pinene, sabinene and beta-pinene were found as the most prominent components in all essential oils. Most importantly, enzyme treatment did not induce transformation of the volatile components, but it contributes to the liberation of some glycosidically bound volatiles. Moreover, it significantly enhances the release of phenolic compounds from the hydro distilled residual leaves and consequently their antioxidant activity. These results suggest that enzyme pre-treatment could be useful for extracting valuables components, and hold good potential for use in food, cosmetic and pharmaceutical industries.

International audience; We aimed in the present study to investigate the protective effect of a myrtle (Myrtus communis L.) berry seed aqueous extract (MBSAE) on acetic acid (AA)-induced colitis in rats as well as the mechanism implicated in this coli-protection. The use of the LC/MS technique allowed us to identify 18 phenolic compounds in the MBSAE. Secondly, we found that the MBSAE inhibited the luminol-amplified chemiluminescence of resting neutrophils and N-formyl-methionylleucyl-phenylalanine (fMLF) or phorbolmyristate acetate (PMA) stimulated neutrophils in a dose-dependent manner. The MBSAE had no effect on superoxide anions, but it inhibited H2O2 production in the cell free system stimulated with horseradish peroxidase (HRPO) and MPO release from the neutrophils. In vivo, the pre-treatment of rats with sulfasalazine (100 mg kg(-1)) and the MBSAE (25, 50, and 100 mg kg(-1)) significantly reduced AA-induced colonic mucosa lesions as well as histopathological changes. The MBSAE counteracted AA-induced lipid peroxidation and the depletion of the activity of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). We also found that the myrtle extract inhibited the increase of the plasma scavenging activity (PSA) and preserved the content of non-enzymatic antioxidants such as sulfhydryl groups (-SH) and reduced glutathione (GSH). More importantly, acetic acid administration increased colonic hydrogen peroxide (H2O2), free iron and calcium levels, while the MBSAE pre-treatment reversed all intracellular mediator perturbations. In conclusion, our data suggests that the MBSAE exerted a potential protective effect against AA-induced injury and oxidative stress in the rat colon. This coli-protection might be related in part to its antioxidant and ROS scavenging activities or by negatively regulating Fenton reaction components such as H2O2 and free iron, which are known to lead to cytotoxicity mediated by intracellular calcium deregulation.

International audience; The present work aims to investigate the maturation-related changes in phenolic profile of Melia azedarach (L.) leaves (young and old) and fruits (pulp and kernel) at two developmental stages. A total of 26 phenolic compounds were identified by high-performance liquid chromatography-diode-array detector-hyphenated with tandem mass spectromdtry (HPLC-DAD-ESI MS/MS). They include phenolic acids, flavonols and flavanols which were found mostly in glycosylated forms. The main phenolic compounds were found to be rutin (5.86-21.33%, of total integrated peak area at 280 nm), quercetin-3-O-neohesperidoside (3.95-8.76%), kaempferol-3-O-rutinoside (2.73-11.23%), feruloylglucaric acid (0.85-11.84%) and feruloylquinic acid derivative (1.94-11.07%). The pattern distribution of phenolic compounds was organ-specific, and somewhat variable depending on the stage of maturation. Additionally, the total phenol content was determined as well as the antioxidant capacity using different in vitro assays. The extracts of young leaves demonstrated the highest total phenol content (85.4 mg GAE/g extract), and exhibited the strongest scavenging activity against 2,2-diphenyl-1-picrylhydrazyl DPPH and the highest oxygen radical absorbance capacity ORAC (235 and 328 mg Trolox equivalents/g extract, respectively) compared to old leaves and immature/mature fruit parts. In contrast, the highest metal chelating activity (MCA) was observed in immature pulp extracts (22.85 mg EDTA equivalents/g extract). Pearson's correlation and principal component analysis (PCA) showed that quercetin-3-O-neohesperidoside, rutin and kaempferol-3-O-rutinoside were the main contributors on the antioxidant capacity. On the basis of these results, M. azedarach could serve as an excellent source of natural antioxidants which could be used for pharmaceutical and cosmeceutical applications.

International audience; New biosourced chiral cross-linkers were reported for the first time in the synthesis of methyltestosterone (MT) chiral molecularly imprinted polymers (cMIPs). Isosorbide and isomannide, known as 1,4:3,6-dianhydrohexitols, were selected as starting diols. The cMIPs were synthesized following a noncovalent approach via thermal radical polymerization and monitored by Raman spectroscopy. These cross-linkers were fully characterized by H-1 and C-13 nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry. The cross-polarization magic angle spinning C-13 NMR, Fourier transform infrared spectroscopy, scanning electron microscopy, and specific surface areas following the Brunauer-Emmett-Teller (BET) method were used to characterize the cMIPs. The effect of stereochemistry of cross-linkers on the reactivity of polymerization, morphology, and adsorption-recognition properties of the MIP was evaluated. The results showed that the cMIP exhibited an obvious improvement in terms of rebinding capacity for MT as compared with the nonimprinted polymer (NIP). The highest binding capacity was observed for cMIP-Is (27.298mgg(-1)) for high concentrations (500mgL(-1)). However, the isomannide homologue cMIP-Im showed higher recoveryup to 65% and capacity for low concentrations (15mgL(-1)). The experimental data were properly fitted by the Freundlich adsorption isothermal model.

International audience; Integrins are essential protagonists in the complex multistep process of cancer progression and are thus attractive targets for the development of anticancer agents. Cucurbitacin B, a triterpenoid purified from the leaves of Tunisian Ecballium elaterium exhibited an anticancer effect and displayed anti-integrin activity on human glioblastoma U87 cells, without being cytotoxic at concentrations up to 500nM. Here we show that cucurbitacin B affected the adhesion and migration of U87 cells to fibronectin in a dose-dependent manner with IC50 values of 86.2nM and 84.6nM, respectively. Time-lapse videomicroscopy showed that cucurbitacin B significantly reduced U87 cells motility and affected directional persistence. Cucurbitacin B also inhibited proliferation with IC50 value of 70.1nM using Crystal Violet assay. Moreover, cucurbitacin B efficiently inhibited in vitro human microvascular endothelial cells (HMEC) angiogenesis with concentration up to 10nM. Interestingly, we demonstrate for the first time that this effect was specifically mediated by α5β1 integrins. These findings reveal a novel mechanism of action for cucurbitacin B, which displays a potential interest as a specific anti-integrin drug.

International audience; In the present study, the effect of Ecbalium elaterium seed oil on adhesion, migration and proliferation of human brain cancer cell line (U87) was determined. Treatment of U87 cell line with the seed oil resulted in strong inhibition of their adhesion to fibrinogen (Fg), fibronectin (Fn). It also reduced their migration and proliferation in a dose-dependent manner without being cytotoxic. Concomitantly, by using Matrigel TM assays, the oil significantly inhibited angiogenesis. The anti-tumor effect of the oil is specifically mediated by avb3 and a5b1 integrins. The presence of integrin antagonists in seed oil from E. elaterium could be used for the development of anticancer drugs with targeted " multi-modal " therapies combining anti-adhesif, antiproliferative, antimetastasic and anti-angiogenic, approaches.

International audience; The composition of the fatty acids of the roots and aerial parts of Aritolochia longa (Aristolacheae) and Bryonia dioica (Cucurbutaceae) was analyzed by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The oils extracted from the aerial parts of both species were rich in polyunsaturated fatty acids with the essential linolenic and linoleic acids being the most prominent compounds. Oleic and linoleic acids were the majors fatty acids in the roots of both species. Whatever the plant part analyzed and the species, the saturated fatty acids were predominantly composed of palmitic and stearic acids. The antibacterial activity, minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the lipid extracts were determined against a panel of five bacterial strains. The results showed that the sensitivity to the lipid extracts was different for the test bacterial strains, and the susceptibility of gram positive bacteria was found to be greater than gram negative bacteria. The antibacterial activity of the root lipid extracts was particularly important against Enterococcus feacium (CMI value of 125 mu g/mL; CMB values > 250 mu g/mL) and Streptococcus agalactiae (CMI value of 125 mu g/mL; CMB values 250 mu g/mL for A. longa roots). These results indicate that A. longa and B. dioica could be considered as good sources of essential fatty acids which can act as natural antibacterial agents.

We gratefully acknowledge Professor Genevieve Casanas for her scientific support in Statistical analysis. We also thank Dany Maitre for her excellent help in the identification of volatile constituents.; International audience; The composition of essential oil is known to depend on intrinsic and extrinsic factors, including season harvest and climate condition among others. Experiments were conducted to study the variation in the essential oil composition of Aristolochia longa ssp. paucinervis harvested at different period (August, 2009; September, 2011; March, 2012; and April, 2013). The essential oil composition was assessed by GC-FID and GC MS analyses, which revealed the presence of 103 molecules. Hence, samples collected in April 2013 showed the most complex composition (51 compounds) when compared with those collected in September 2011 (42 compounds), August 2009 (37 compounds) and March 2012 (35 compounds). Further, oxygenated sesquiterpenes (50.2-81.1%) and oxygenated monoterpenes (5.9-28.0%) are the major chemical groups.The antimicrobial properties of essential oils were evaluated against six microorganisms by the disc diffusion method. The highest activity is observed against all the Gram-positive bacteria. Increasingly, the essential oil isolated from roots collected in September (2011), exhibited the highest antimicrobial activity against Streptococcus agalactiae and Enterococcus faecium

The synthesis of biosourced copolyethersulfones by polycondensation of 1,4:3,6-dianhydrohexitol monomers and bisphenol A is reported. Structures and properties of these copolymers were investigated in each case. In the first part, the impact of the position of the two hydroxyl groups of isosorbide, isomannide, and isoidide is discussed. In the second part, we focused on improving the cost/thermal properties balance by introducing controlled proportions of bisphenol A as comonomer. The addition of bisphenol A serves two purposes. The first one is to maintain good thermal and mechanical properties of resulting copolymers. The second reason is to insure low-cost route to copolyethersulfones for a potential use in industrial applications. All the products have been fully characterized by NMR spectroscopy, MALDI-TOF spectrometry, and viscosimetry. The thermal properties were studied by differential scanning calorimetry (DSC).

International audience; Introduction: Rapid determination of microorganisms' antibiotic susceptibility remains a great challenge for the clinical diagnosis of infectious diseases. In this study, we compare three rapid bioluminescent antibiotic susceptibility tests with the conventional normalised microdilution method. Methods: The susceptibility of two bacterial and two fungal strains to a 6 h incubation with one of eight standard antibiotics was investigated by the ATP, AK and QNO bioluminescent methods. Results: Three rapid and accurate antibiotic susceptibility testing were investigated performing ATP, AK and QNO bioluminescent assays. All the results were in accordance with those obtained using a standard microdilution assay. All these methods were sensitive and faster than the previously well-known ones. Discussion: The development of bioluminescent determination methods could lead to accurate and useful antibiotic susceptibility testing. (C) 2009 Elsevier Inc. All rights reserved.

International audience; A comprehensive analysis of the responses of Nigella sativa L. to elevated zinc concentrations was assessed in pot experiments. Zn excess supply did not affect the germination but drastically reduced radicle elongation. A concentration-dependent reduction in all growth parameters, yield, and yield components was observed. With the increasing Zn concentrations, total lipid contents decreased and changes in fatty composition toward the production of saturated ones were underscored. Despite the reduction in the seeds essential oil yield, a redirection of the terpene metabolism toward the synthesis of oxygenated compounds has been evidenced. A significant increase in the total phenols and flavonoids contents concomitant with improved antioxidant activities has also been found. Collectively, these results highlight the possible use of N. sativa L. in phytoremediation applications, on the one hand, and that Zn excess could represent an excellent alternative to improve the nutritional attributes of this important species, on the other hand.

International audience; New biosourced unprotected diols were prepared by acylation reaction of aminoalcohol based on 1,4: 3,6-dianhydrosorbitol (Isosorbide Is) with several aliphatic and aromatic diacyl chlorides (sebacoyl, adipoyl, and terephthaloyl). Optimization of reaction conditions (solvent, base nature, and addition mode) has been investigated with protected alcohols. The use of hindered bases was needful to ensure the selectivity of the addition reaction when starting from unprotected aminoalcohol, and selectively led to bis amides products with good yields. 1D and 2D NMR techniques were used to ascertain the structures of the unprecedented monomers. These novel building blocks were successfully polymerized using succinic and terephthalic spacers and studied by NMR and DSC techniques.

International audience; Two series of 1,2,3-triazolium chiral ionic liquid (CIL) stereoisomers are synthesized from isosorbide by combining the robust attributes of the copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC), alkylation of the resulting 1,2,3-triazoles by methyl iodide and further anion metathesis with different fluorinated salts. These novel biosourced CILs are characterized in details by H-1 and C-13 NMR spectroscopy, high-resolution mass spectrometry (ESI-HRMS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and broadband dielectric spectroscopy (BDS). The effect of stereochemistry on their physical, thermal and ion conducting properties is discussed. Markedly, it is demonstrated for the first time that stereochemistry can drastically influence ionic conductivity by several orders of magnitude.

Authors want to thank all INRAP staff for analysis and helpful discussion. M. Mezni is acknowledged for NMR experiments, R. Jebali and N. Chaabane for ICP analysis.; International audience; Isosorbide and isomannide are polycondensed in solution with trimesoyl chloride at a concentration of 0.06 mol L-1 for the synthesis of cyclic and multicyclic polyesters. The feed ratio diol/trimesoyl chloride is varied from 1.0/1.0 to 1.6/1.0. As all obtained polyesters prove insoluble, innovative solvent-free matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI ToF MS) is performed for their characterization. The influence of the stereochemistry is shown to be of great importance for the cyclization trend. Both isosorbide and isomannide lead mainly to cyclic and multicyclic structures at a feed ratio of 1.0/1.0 and 1.1/1.0. Isomannide gives higher fractions of multicyclic structures. The products are characterized by complementary techniques such as C-13 cross polarization magic angle spinning nuclear magnetic resonance (C-13 CP-MAS NMR) and differential scanning calorimetry measurements. Application as a cryptands for the uptake of metal ions in aqueous media is followed by inductively coupled plasma atomic emission spectroscopy (ICP AES) analysis and reveal efficient toward large range of metals with tunable selectivity depending on the starting diol.

International audience; Functionalization of bio-based oligomers is a relevant approach in order to allow these materials to replace more conventional and nonbiodegradable polymers in a wider range of applications. This article will report on the hydroxylation of isosorbide-based ethersulfone oligomers. The hydroxy end-group was controlled by the variation of polycondensation parameters. Comparative study was conducted to assess the effect of isosorbide excess and the monomer concentration on structural composition and molecular weights of produced oligomers. Depending on reaction conditions, various products were synthesized, mainly alpha,omega-dihydroxyethersulfone oligomers. The characterization of the synthesized polyethersulfone was demonstrated by MALDI-TOF, NMR spectroscopy, differential scanning calorimetry, and size exclusion chromatography.

In this work the physicochemical characteristics including fatty acids, tocopherols and sterols composition of Ecballium elaterium (L.) A. Rich seed oil was determined. Results showed that linoleic acid (48.64%) and punicic acid (22.38%) were the major polyunsaturated fatty acids. Among the phytosterols, β-sitosterol was the most abundant (396.25 mg/100 g), while the major tocopherol form was γ-tocopherol (44.23 mg/100 g). In addition, we evaluated for the first time the effect of E. elaterium seed oil on the growth of human colonic adenocarcinoma (HT29) and fibrosarcoma (HT1080) cell lines. The original finding was its potent antiproliferative effect on both tumour cell lines. This effect was dose-dependent, with half-maximal inhibition values of IC50 = 4.86 μg/ml and 4.16 μg/ml respectively. This pilot study opens the way for further investigation about the potential use of E. elaterium as an anticancer agent. Keywords: Ecballium elaterium, Seed oil, Chemical composition, Antiproliferative activity, Colon cancer

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International audience; The chemical composition of the volatile oils obtained from the roots, leaves, flowers, and stems of Thapsia garganica of Tunisian origin was investigated by GC-FID and GC/MS analyses. Sesquiterpene hydrocarbons and oxygenated monoterpenes were predominant in the oils of all plant parts. Bicyclogermacrene (21.59-35.09%) was the main component in the former compound class, whereas geranial (3.31-14.84%) and linalool (0.81-10.9%) were the most prominent ones in the latter compound class. Principal-component (PCA) and hierarchical-cluster (HCA) analyses revealed some common constituents, but also significant variability amongst the oils of the different plant parts. This organ-specific oil composition was discussed in relation to their biological and ecological functions. For the evaluation of the intraspecific chemical variability in T. garganica, the composition of the flower volatile oils from four wild populations was investigated. Bicyclogermacrene, linalool, and geranial were predominant in the oils of three populations, whereas epicubenol, -sesquiphellandrene, and cadina-1,4-diene were the most prominent components of the oil of one population. PCA and HCA allowed the separation of the flower oils into three distinct groups, however, no relationship was found between the volatile-oil composition and the geographical distribution and pedoclimatic conditions of the studied populations.

The essential oil of Murraya crenulata (Turcz.) Oliver (Rutaceae) was obtained from fresh leaves by hydrodistillation of plant material collected in Lifou, Loyalty Islands, New Caledonia. Analysis by a combination of GC and GC–MS indicates a characteristic chemical composition dominated by p-menthane derivatives, mainly perilla aldehyde (73.2%), limonene (8.2%), perilla alcohol (6.5%) and its acetate (6.0%). Copyright © 2006 John Wiley & Sons, Ltd.

International audience; The present study aims at evaluating the antiulcer and antioxidant effect of Artemisia campestris aqueous extract (ACAE) as well as the mechanism of action involved in such gastroprotection. The use of LC/MS allowed the identification of 11 phenolic compounds and the colorimetric analysis demonstrated that the ACAE exhibited an important in vitro antioxidant activity. We first showed that in vivo ACAE protected against macroscopic and histological changes induced by aspirin in stomach mucosa. Aspirin administration was accompanied by an oxidative stress status assessed by an increase in malondialdehyde (MDA) level, a decrease in the content of sulfhydryl -(SH) groups and a depletion of antioxidant enzyme activities such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). Pre-treatment with ACAE protected against aspirin-induced gastric oxidative stress. More importantly, aspirin administration increased plasma and tissue hydrogen peroxide (H2O2), free iron and calcium levels, while the ACAE pre-treatment reversed all the effects of aspirin-induced intracellular mediators. In conclusion, we suggest that Artemisia campestris aqueous extract has potent antiulcer and antioxidant properties. This gastroprotection offered by ACAE might be related partly to the safety of sulfhydryl group as well as its opposite effect on some intracellular mediators such as hydrogen peroxide, free iron and calcium.

International audience; New series of polyether-amides were prepared by polycondensation in solution of three diamines based on 1,4-3,6-dianhydrohexitols with two types of diacyl chlorides (sebacoyl and isophtaloyl). Unprecedented diamines based on isomannide and isoidide were elaborated. The corresponding polyether-amides (PeA) were obtained with high yields. They were characterized by different analytical techniques (NMR, MALDI-ToF MS, DSC). The combination of MALDI-ToF MS with NMR spectroscopy allowed us to confirm structure types. DSC measurements revealed an amorphous character for the isophtaloyl family with a high Tg value. The sebacoyl series proved to be semi-crystalline with a high Tm value. Isosorbide-based PeAs demonstrated interesting properties (Tg above 210 °C and Tm above 240 °C) and high viscosity (0.32).

New classes of amphiphilic polyesters were prepared from metallated (Si, Ge) fatty methyl ester (FAME) precursors and poly(tetramethylene oxide) glycol. Hydrosilylation of 10-undecenoic methyl ester by tetramethyldisiloxane occurred at 80 degrees C in the presence of Karstedt's catalyst, and hydrogermylation of the same FAME derivative was obtained at the same temperature under radical AIBN initiation. These diester precursors, obtained in high yields (approximately 90%), reacted with poly(tetramethylene oxide) glycol under free solvent to give silicon polymers or germanium oligomers. These condensed materials display both the characteristic of organic-inorganic hybrid materials and those of amphiphilic polymers. The nature of organometallic fragment (hydrophobicity of tetramethyldisiloxy and sterical hindrance of diphenylgermyl) was shown to influence the chemical reactivity of the polymerizable monomers and the physical properties of the resulting copolymers. The amphiphilicity of these materials provides a driving force for the formation of small objects (approximately 1 nm), making them very attractive as hybrid nanocontainers.

A simple and efficient method for producing amphiphilic germylated compounds has been developed by hydrogermylation of fatty acid methyl esters. The germylated precursors afford a micelle-type assembly in various solvents as evident by the formation of nano-objects, micrometer spheres and lamellar forms. This offers a promising route to synthetically useful monomers for structured materials. Copyright © 2008 John Wiley & Sons, Ltd.

The essential oils obtained by hydrodistillation of pieces of dead trunks of Callitris sulcata (Parlatore) Schlechter and Callitris neocaledonica Dummer were investigated by gas chromatography, mass spectrometry and NMR spectroscopy. Analyses evidenced the presence of rare natural compounds: both essential oils are exclusively sesquiterpenic with nevertheless remarkable difference: C. sulcata essential oil was dominated by β-barbatene and thujopsene while C. neocaledonica was characterized by high levels of guaiane- and eudesmane-type structures (eudesmols, guaiol and related components). The biochemical correlations between the major components of each species are discussed and the relationship between the two species is commented.

As part of our search for new antimalarial drugs, we have screened for inhibitors of Pfnek-1, a protein kinase of Plasmodium falciparum, in south Pacific marine sponges. On the basis of a preliminary screening, the ethanolic crude extract of a new species of Xestospongia collected in Vanuatu was selected for its promising activity. A bioassay-guided fractionation led us to isolate xestoquinone which inhibits Pfnek-1 with an IC50 around 1 mu M. Among a small panel of plasmodial protein kinases, xestoquinone showed modest protein kinase inhibitory activity toward PfPK5 and no activity toward PfPK7 and PfGSK-3. Xestoquinone showed in vitro antiplasmodial activity against a FCB1 P. falciparum strain with an IC50 of 3 mu M and a weak selectivity index (SI 7). Xestoquinone exhibited a weak in vivo activity at 5 mg/kg in Plasmodium berghei NK65 infected mice and was toxic at higher doses. (c) 2006 Elsevier Ltd. All rights reserved.

Hydrometalation of carbon−carbon double bonds by group 14 hydrides is inhibited by carbonyl compoundsmainly by α,β-unsaturated carbonyl groupsas efficiently as by classical radical trapping compounds, such as galvinoxyl and hydroquinone. This phenomenon, in the case of polyfunctional CC- and CO-containing compounds, such as carvone, leads to an autoinhibition of the exocyclic alkenylic hydrometalation under normal reaction conditions, while under drastic conditions, the O-metalation of the α,β-unsaturated carbonyl group occurs.

Review; Ciguatera is the most common food poisoning found in the tropical and subtropical areas, acquired by the consumption of marine products. A lot of work concerning its etiology, its epidemiology and its clinical effects, as well as the discovery of the toxins involved, the description of their transfer, the study of their structure and the analysis of their pharmacological effects, have allowed a better understanding of the ciguateric phenomenon. Ciguatera is known to be due to benthic dinoflagellates belonging to the Gambierdiscus gender, in particular G. toxicus. Under specific conditions, this microalga produces gambier-toxins, toxins which are the precursors of other toxins, the ciguatoxins. However, the factors supporting this production are still poorly known, and the implication of others dinoflagellates, cyanophytes or bacteria have been suspected. In contrast, the fish species responsible for the transmission of ciguatera are globally well identified. The clinical symptoms of the intoxication are now well described. They mainly include digestive, neurological and cardiovascular disorders whose preponderance varies according to the nature of the toxins involved, since toxin structures are different between one ocean and the other. The ciguateric intoxication tends to be exported towards non endemic areas where it is still misdiagnosed. No specific antidote exists to date, and it is only by symptomatic or palliative treatments that ciguatera is currently treated.

A new specific voltage-sensitive calcium channel (VSCC) blocker has been isolated from the venom of the fish-hunting cone snail Conus consors. This peptide, named omega-Ctx CNVIIA, consists of 27 amino acid residues folded by 3 disulfide bridges. Interestingly, loop 4, which is supposed to be crucial for selectivity, shows an unusual sequence (SSSKGR). The synthesis of the linear peptide was performed using the Fmoc strategy, and the correct folding was achieved in the presence of guanidinium chloride, potassium buffer, and reduced/oxidized glutathione at 4 degrees C for 3 days. Both synthetic and native toxin caused an intense shaking activity, characteristic of omega-conotoxins targeting N-type VSCC when injected intracerebroventricularly to mice. Binding studies on rat brain synaptosomes revealed that the radioiodinated omega-Ctx CNVIIA specifically and reversibly binds to high-affinity sites with a K(d) of 36.3 pM. Its binding is competitive with omega-Ctx MVIIA at low concentration (K(i) = 2 pM). Moreover, omega-Ctx CNVIIA exhibits a clear selectivity for N-type VSCCs versus P/Q-type VSCCs targeted respectively by radioiodinated omega-Ctx GVIA and omega-Ctx MVIIC. Although omega-Ctx CNVIIA clearly blocked N-type Ca(2+) current in chromaffin cells, this toxin did not inhibit acetylcholine release evoked by nerve stimuli at the frog neuromuscular junction, in marked contrast to omega-Ctx GVIA. omega-Ctx CNVIIA thus represents a new selective tool for blocking N-type VSCC that displays a unique pharmacological profile and highlights the diversity of voltage-sensitive Ca(2+) channels in the animal kingdom.

International audience; A novel conotoxin was isolated and characterized from the venom of the fish-hunting marine snail Conus consors. The peptide was identified by screening chromatography fractions of the crude venom that produced a marked contraction and extension of the caudal and dorsal fins in fish, and noticeable spontaneous contractions of isolated frog neuromuscular preparations. The peptide, named CcTX, had 30 amino acids and the following scaffold: X11CCX7CX2CXCX3C. At the frog neuromuscular junction, CcTx at nanomolar concentrations selectively increased nerve terminal excitability so that a single nerve stimulation triggered trains of repetitive or spontaneous synaptic potentials and action potentials. In contrast, CcTx had no noticeable effect on muscle excitability even at concentrations 100 x higher than those that affected motor nerve terminals, as revealed by direct muscle stimulation. In addition, CcTx increased miniature endplate potential (MEPP) frequency in a Ca2+-free medium supplemented with ethylene glycol-bis-(beta-aminoethyl ether)-N,N,N', N'-tetraacetic acid (EGTA). Blockade of voltage-dependent sodium channels with tetrodotoxin (TTX) either prevented or suppressed the increase of MEPP frequency induced by the toxin. CcTx also produced a TTX-sensitive depolarization of the nodal membrane in single myelinated axons giving rise, in some cases, to repetitive and/or spontaneous action potential discharges. In addition, CcTx increased the nodal volume of myelinated axons, as determined using confocal laser scanning microscopy. This increase was reversed by external hyperosmolar solutions and was prevented by pretreatment of axons with TTX. It is suggested that CcTx, by specifically activating neuronal voltage-gated sodium channels at the resting membrane potential, produced Na+ entry into nerve terminals and axons without directly affecting skeletal muscle fibres. CcTx belongs to a novel family of conotoxins that targets neuronal voltage-gated sodium channels.

International audience; In this paper, we present an overview of the biodiversity of both marine snails of the large genus Conus and their venoms. After a brief survey of Conidae malacology, we focus on the high degree of biodiversity of this genus, its specific biogeography as well as its habitat, and the relatively strict diet of its members. The venom of Conidae species contains a large number of peptides that can interact selectively with key elements of the peripheral and central nervous systems of vertebrates and invertebrates. Emphasis is on summarizing our current knowledge of the specific actions of venom components on ionic channels, receptors and other key elements of cellular communication. The peptides isolated from venoms, called conotoxins, form different families according to both their primary structure and their specific pharmacological targets. Three families encompassing the mu-, muO- and delta-conotoxins target voltage-sensitive sodium channels but with different modes of action or tissue selectivity. Another important class of conotoxins is the omega-conotoxin family which acts on voltage-sensitive calcium channels. The alpha-conotoxin family is represented by several peptides blocking muscular or neuronal nicotinic acetylcholine receptors. Finally, a blocker of potassium channels is presented as well as two conotoxins acting on the N-Methyl-D-Aspartate receptor. Primary structures and cysteine frameworks of all these conotoxins are shown and compared. At the end of the review, we report the contribution of molecular biology to identification of new conotoxins having original pharmacological properties. In conclusion, conotoxins have received increasing attention from physiologists, pharmacologists, biochemists and physicians because of their selectivity as well as their pharmacological and therapeutic potential.