HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
HAL (Le Centre pour la Communication Scientifique Directe), 1993
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Among the Leguminosae, two genera were recently described as forming efficient nodulation with th... more Among the Leguminosae, two genera were recently described as forming efficient nodulation with the bacterial genus Methylobacterium: Crotalaria and Lotononis. Methylobacterium are able to utilize methanol and other C 1 compounds as a sole source of carbon and energy. Originally isolated from Crotalaria podocarpa, C. perrotetti and C. glaucoides, M. nodulans was proved to possess the gene mxaF coding for methanol dehydrogenase large subunit. Plants inoculated by mutants altered in methylotrophy were found to be drastically affected in nodule number and growth. This study aims at describing some histological and cytological characteristics of C. podocarpa nodules induced by Methylobacterium ORS 20601 strain. Mature C. podocarpa nodules are multilobed anchored to the root at one single pod. Within one mature lobe tissues are organized as described in classical indeterminate nodules like Medicago. Within invasion zone II, bacteria are present as classical rods both in intercellular spaces and also intracellularly. Infection threads are not observed nor within root hairs, neither delivering bacteria to young plant cells. Bacteroids within fixation zone III are globally spherical with an average diameter of 4 µm. In the apical zone of mature, fully elongated nodules, the invasion zone rapidly appears to take an unusual shape with a progressive loss of plant cell wall integrity, clearly revealed by cell wall stains. The whole zone is disorganized with no more subsistence of any plant cell wall. Mutants affected in methylotrophy do not induce such lysis. Interestingly, beyond their methylotrophy impairment, mxaF mutants also loose their ability to use methylated pectins in pure culture. We hypothesize that methanol could be produced from cell-wall pectin demethylation in this apical zone, where mxaF gene expression has been localized. (Texte integral)
HAL (Le Centre pour la Communication Scientifique Directe), Nov 21, 2016
International audience1. Le règne fongique : caractères généraux et diversité 2. Modes de vie (st... more International audience1. Le règne fongique : caractères généraux et diversité 2. Modes de vie (stratégie nutritive) 3. Le cycle biologique des Basidiomycota 4. Les Champignons utiles 5. Les Champignons nuisible
Fungi provide ecological and environmental services to humans, as well as health and nutritional ... more Fungi provide ecological and environmental services to humans, as well as health and nutritional benefits, and are vital to numerous industries. Fermented food and beverage products from fungi are circulating in the market, generating billions of USD. However, the highest potential monetary value of fungi is their role in blue carbon trading because of their ability to sequester large amounts of carbon in the soil. There are no conclusive estimates available on the global monetary value of fungi, primarily because there are limited data for extrapolation. This study outlines the contribution of fungi to the global economy and provides a first attempt at quantifying the global monetary value of fungi. Our estimate of USD 54.57 trillion provides a starting point that can be analysed and improved, highlighting the significance of fungi and providing an appreciation of their value. This paper identifies the different economically valuable products and services provided by fungi. By giving a monetary value to all important fungal products, services, and industrial applications underscores their significance in biodiversity and conservation. Furthermore, if the value of fungi is well established, they will be considered in future policies for effective ecosystem management.
Amatoxins, bicyclic octapeptide derivatives responsible for severe hepatic failure, are present i... more Amatoxins, bicyclic octapeptide derivatives responsible for severe hepatic failure, are present in several Basidiomycota species belonging to four genera, i.e. Amanita, Conocybe, Galerina and Lepiota. DNA studies for G. autumnalis, G. marginata, G. oregonensis, G. unicolor and G. venenata (section Naucoriopsis) determined that these species are the same, supporting the concept of Galerina marginata complex. These mostly lignicolous species are designated as white-rot fungi having a broad host range and capable of degrading both hardwoods and softwoods. Twenty-seven G. marginata basidiomes taken from different sites and hosts (three sets) as well as 17 A. phalloides specimens (three sets) were collected in French locations. The 44 basidiomes were examined for amatoxins and phallotoxins using high-performance liquid chromatography. Toxinological data for the wood-rotting G. marginata and the ectomycorrhizal A. phalloides species were compared and statistically analyzed. The acidic and neutral phallotoxins were not detected in any G. marginata specimen, whereas the acidic (β-Ama) and neutral (α-Ama and γ-Ama) amanitins were found in all basidiomes from either Angiosperms or Gymnosperms hosts. The G. marginata amatoxin content varied from 78.17 to 243.61 μg.mg−1 of fresh weight and was elevated significantly in one set out of three. The amanitin amounts from certain Galerina specimens were higher than those from some A. phalloides basidiomes. Relationship between the amanitin distribution and the chemical composition of substrate was underlined and statistically validated for the white-rot G. marginata. Changes in nutritional components from decayed host due to enzymatic systems and genetic factors as well as environmental conditions seem to play a determinant role in the amanitin profile. Variability noticed in the amanitin distribution for the white-rot G. marginata basidiomes was not observed for the ectomycorrhizal A. phalloides specimens.
HAL (Le Centre pour la Communication Scientifique Directe), Oct 27, 2010
International audienceOral communication. Argania spinosa (L.) Skeels (Sapotaceae) is an endemic ... more International audienceOral communication. Argania spinosa (L.) Skeels (Sapotaceae) is an endemic tree located mainly in south-western of Morocco. The argan tree plays medicinal, ecological and socioeconomic roles in this area. The fruit of A. spinosa has oil-producing kernels with a high unsaturated fatty acid content. The argan oil is greatly used in food and cosmetic products. Kernel, pulp of fruit and trunk have also been studied for sterols, triterpenes and saponins. Our goal in this study is to investigate the leaves for phenolic compounds by HPLC in 90 specimens of argan tree from three localities in Souss Massa area (south-western Morocco). Quantification and histolocalisation of phenolic components, i. e. flavonoids and condensed tannins (molecules well known for their broad spectrum of biological activities) in the three localities were carried out using chromatographic and spectroscopic methods combined to histochemical technics. Flavonol glycosides were quantified by HPLC from argan leaves. The main flavonol glycoside was myricitrin. The content of myricetin derivatives was higher than the quercetin derivative content. With regard to chemotaxonomy, four flavonol glycosides seem to be good markers for this species as they were detected by HPLC in 90 specimens of argan tree from the 3 localities. The histochemical studies of the different parts of A. spinosa (leaves, stems and thorns) have shown a high concentration of myricetin derivatives in the peripheral tissues, this cell localisation of the flavonoids could explain the Argan tree adaptation to aridit
De nombreuses medecines alternatives (ou pratiques therapeutiques non conventionnelles) et en par... more De nombreuses medecines alternatives (ou pratiques therapeutiques non conventionnelles) et en particulier de fondement holistique comme la Medecine Traditionnelle Chinoise (MTC) sont actuellement largement utilisees en complement de l’arsenal chimiotherapique curatif (ou medecine allopathique) [1, 2]. Un prix Nobel decerne en 2015 au Pr Y.You. Tu a particulierement distingue la MTC en passe d’etre reconnue en 2019 par l’Organisation Mondiale de la Sante [3, 4]. Methode : Differents travaux de synthese ont ete realises sur l’efficacite therapeutique des plantes utilisees en MTC [2, 5, 6]. Discussion : Des etudes cliniques sont ici rapportees quant aux preuves d’efficacite pour traiter des patients atteints de differentes pathologies [7, 8]. Cependant, certaines plantes utilisees n’etant pas denuees de toxicite, elles necessitent une transformation particuliere et un prescripteur confirme pour eviter tout accident [2, 5, 6, 9].
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
HAL (Le Centre pour la Communication Scientifique Directe), 1993
HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.
Among the Leguminosae, two genera were recently described as forming efficient nodulation with th... more Among the Leguminosae, two genera were recently described as forming efficient nodulation with the bacterial genus Methylobacterium: Crotalaria and Lotononis. Methylobacterium are able to utilize methanol and other C 1 compounds as a sole source of carbon and energy. Originally isolated from Crotalaria podocarpa, C. perrotetti and C. glaucoides, M. nodulans was proved to possess the gene mxaF coding for methanol dehydrogenase large subunit. Plants inoculated by mutants altered in methylotrophy were found to be drastically affected in nodule number and growth. This study aims at describing some histological and cytological characteristics of C. podocarpa nodules induced by Methylobacterium ORS 20601 strain. Mature C. podocarpa nodules are multilobed anchored to the root at one single pod. Within one mature lobe tissues are organized as described in classical indeterminate nodules like Medicago. Within invasion zone II, bacteria are present as classical rods both in intercellular spaces and also intracellularly. Infection threads are not observed nor within root hairs, neither delivering bacteria to young plant cells. Bacteroids within fixation zone III are globally spherical with an average diameter of 4 µm. In the apical zone of mature, fully elongated nodules, the invasion zone rapidly appears to take an unusual shape with a progressive loss of plant cell wall integrity, clearly revealed by cell wall stains. The whole zone is disorganized with no more subsistence of any plant cell wall. Mutants affected in methylotrophy do not induce such lysis. Interestingly, beyond their methylotrophy impairment, mxaF mutants also loose their ability to use methylated pectins in pure culture. We hypothesize that methanol could be produced from cell-wall pectin demethylation in this apical zone, where mxaF gene expression has been localized. (Texte integral)
HAL (Le Centre pour la Communication Scientifique Directe), Nov 21, 2016
International audience1. Le règne fongique : caractères généraux et diversité 2. Modes de vie (st... more International audience1. Le règne fongique : caractères généraux et diversité 2. Modes de vie (stratégie nutritive) 3. Le cycle biologique des Basidiomycota 4. Les Champignons utiles 5. Les Champignons nuisible
Fungi provide ecological and environmental services to humans, as well as health and nutritional ... more Fungi provide ecological and environmental services to humans, as well as health and nutritional benefits, and are vital to numerous industries. Fermented food and beverage products from fungi are circulating in the market, generating billions of USD. However, the highest potential monetary value of fungi is their role in blue carbon trading because of their ability to sequester large amounts of carbon in the soil. There are no conclusive estimates available on the global monetary value of fungi, primarily because there are limited data for extrapolation. This study outlines the contribution of fungi to the global economy and provides a first attempt at quantifying the global monetary value of fungi. Our estimate of USD 54.57 trillion provides a starting point that can be analysed and improved, highlighting the significance of fungi and providing an appreciation of their value. This paper identifies the different economically valuable products and services provided by fungi. By giving a monetary value to all important fungal products, services, and industrial applications underscores their significance in biodiversity and conservation. Furthermore, if the value of fungi is well established, they will be considered in future policies for effective ecosystem management.
Amatoxins, bicyclic octapeptide derivatives responsible for severe hepatic failure, are present i... more Amatoxins, bicyclic octapeptide derivatives responsible for severe hepatic failure, are present in several Basidiomycota species belonging to four genera, i.e. Amanita, Conocybe, Galerina and Lepiota. DNA studies for G. autumnalis, G. marginata, G. oregonensis, G. unicolor and G. venenata (section Naucoriopsis) determined that these species are the same, supporting the concept of Galerina marginata complex. These mostly lignicolous species are designated as white-rot fungi having a broad host range and capable of degrading both hardwoods and softwoods. Twenty-seven G. marginata basidiomes taken from different sites and hosts (three sets) as well as 17 A. phalloides specimens (three sets) were collected in French locations. The 44 basidiomes were examined for amatoxins and phallotoxins using high-performance liquid chromatography. Toxinological data for the wood-rotting G. marginata and the ectomycorrhizal A. phalloides species were compared and statistically analyzed. The acidic and neutral phallotoxins were not detected in any G. marginata specimen, whereas the acidic (β-Ama) and neutral (α-Ama and γ-Ama) amanitins were found in all basidiomes from either Angiosperms or Gymnosperms hosts. The G. marginata amatoxin content varied from 78.17 to 243.61 μg.mg−1 of fresh weight and was elevated significantly in one set out of three. The amanitin amounts from certain Galerina specimens were higher than those from some A. phalloides basidiomes. Relationship between the amanitin distribution and the chemical composition of substrate was underlined and statistically validated for the white-rot G. marginata. Changes in nutritional components from decayed host due to enzymatic systems and genetic factors as well as environmental conditions seem to play a determinant role in the amanitin profile. Variability noticed in the amanitin distribution for the white-rot G. marginata basidiomes was not observed for the ectomycorrhizal A. phalloides specimens.
HAL (Le Centre pour la Communication Scientifique Directe), Oct 27, 2010
International audienceOral communication. Argania spinosa (L.) Skeels (Sapotaceae) is an endemic ... more International audienceOral communication. Argania spinosa (L.) Skeels (Sapotaceae) is an endemic tree located mainly in south-western of Morocco. The argan tree plays medicinal, ecological and socioeconomic roles in this area. The fruit of A. spinosa has oil-producing kernels with a high unsaturated fatty acid content. The argan oil is greatly used in food and cosmetic products. Kernel, pulp of fruit and trunk have also been studied for sterols, triterpenes and saponins. Our goal in this study is to investigate the leaves for phenolic compounds by HPLC in 90 specimens of argan tree from three localities in Souss Massa area (south-western Morocco). Quantification and histolocalisation of phenolic components, i. e. flavonoids and condensed tannins (molecules well known for their broad spectrum of biological activities) in the three localities were carried out using chromatographic and spectroscopic methods combined to histochemical technics. Flavonol glycosides were quantified by HPLC from argan leaves. The main flavonol glycoside was myricitrin. The content of myricetin derivatives was higher than the quercetin derivative content. With regard to chemotaxonomy, four flavonol glycosides seem to be good markers for this species as they were detected by HPLC in 90 specimens of argan tree from the 3 localities. The histochemical studies of the different parts of A. spinosa (leaves, stems and thorns) have shown a high concentration of myricetin derivatives in the peripheral tissues, this cell localisation of the flavonoids could explain the Argan tree adaptation to aridit
De nombreuses medecines alternatives (ou pratiques therapeutiques non conventionnelles) et en par... more De nombreuses medecines alternatives (ou pratiques therapeutiques non conventionnelles) et en particulier de fondement holistique comme la Medecine Traditionnelle Chinoise (MTC) sont actuellement largement utilisees en complement de l’arsenal chimiotherapique curatif (ou medecine allopathique) [1, 2]. Un prix Nobel decerne en 2015 au Pr Y.You. Tu a particulierement distingue la MTC en passe d’etre reconnue en 2019 par l’Organisation Mondiale de la Sante [3, 4]. Methode : Differents travaux de synthese ont ete realises sur l’efficacite therapeutique des plantes utilisees en MTC [2, 5, 6]. Discussion : Des etudes cliniques sont ici rapportees quant aux preuves d’efficacite pour traiter des patients atteints de differentes pathologies [7, 8]. Cependant, certaines plantes utilisees n’etant pas denuees de toxicite, elles necessitent une transformation particuliere et un prescripteur confirme pour eviter tout accident [2, 5, 6, 9].
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