Structures spécifiques des peuplements de rongeurs d'agro-écosystèmes et d'écosystèmes « naturels » de la Guadeloupe et de la Martinique

The Muridae rodent community of Guadeloupe and Martinique (French West Indies) includes 3 alien species: the Ship Rat (Rattus rattus), the Norwegian Rat (Rattus norvegicus) and the House Mouse (Mus musculus). A 26,740 trap-night effort conducted under standardized sampling methods showed a strong heterogeneity of the species frequency distribution among 4 agricultural ecosystems (sugar cane, banana, cassava and watermelon) and 3 "natural" ones (tropical rain forest and islands or islets covered either totally or partially by a dry vegetation). A second step of the analysis conducted at a smaller space scale, from the surrounding ecosystems of the cultivated areas to the inside of these ones, gave the same result. The House Mouse constituted the majority of the captures in the agricultural ecosystems (56% for the total and 84% for sugar cane specifically). This species is well represented inside the cultivated area and poorly outside. The Ship Rat is well represented in the "savannah" and "thorn-scrub", and in tropical rain forest, habitats that surround sugar cane and banana fields respectively. Statistically less numerous than the others, the Norwegian Rat was nevertheless well represented in the cultivated area devoted to watermelon and cassava, and concentrated in the field margins. The build-up and the optimisation of strategies for controlling the alien rodents in tropical islands are discussed in relation to these results. The build-up of sampling strategies to evaluate epidemiological and environmental risks due to these alien rodents is also discussed. This last discussion was done in the light of a new result showing that 57% of sampled Guadeloupe House Mice hosted Leptospira interrogans on their kidneysLe peuplement de rongeurs muridés de la Guadeloupe et de la Martinique est constitué de 3 espèces allochtones, le Rat noir (Rattus rattus), le Rat surmulot (Rattus norvegicus) et la Souris domestique (Mus musculus). Un effort d'échantillonnage standardisé de 26 740 nuits-pièges a permis de mettre en évidence une grande hétérogénéité de la distribution de ces espèces au sein d'un ensemble de 4 agro-écosystèmes (canne à sucre, banane, manioc et pastèque) et de 3 écosystèmes naturels (forêt tropicale humide et 2 types d'îles ou îlots à végétation xérophile). Une analyse des résultats, conduite à une échelle spatiale plus fine, depuis les milieux encaissant les parcelles cultivées jusque dans celles-ci, aboutit à la même conclusion. Les Souris domestiques constituent la majorité des captures réalisées sur l'ensemble des agro-écosystèmes étudiés (56 % pour l'ensemble et jusqu'à 84 % pour les agro-écosystèmes canniers). L'espèce est fortement représentée au sein des parcelles cultivées et faiblement dans les milieux encaissants. Le Rat noir est fortement représenté dans les savanes et formations d'épineux d'une part, et la forêt tropicale humide d'autre part, ces milieux constituant respectivement l'environnement immédiat des champs de canne et des bananeraies. Le Surmulot, significativement moins abondant que les espèces précédentes, est cependant bien représenté dans les agro-écosystèmes consacrés aux cultures vivrières et se concentre dans l'écotone que constitue la marge des parcelles cultivées. Ces résultats induisent une réflexion sur l'optimisation des stratégies de lutte anti-rongeurs en vigueur, d'une part, et des stratégies d'échantillonnage destinées à évaluer des risques épidémiologiques ou environnementaux en rapport avec la présence de ces rongeurs, d'autre part. Ils sont discutés en relation avec la mise en évidence récente du portage rénal de Leptospira interrogans par 57 % des souris d'un échantillon collecté à la Guadeloupe

Physicochemical and rheological characterizations of Cocos nucifera L. and Elaeis guineensis Jacq. (Arecaceae) oils for black hair shampoo formulation

Black hair suffers from a lipid deficiency, either on the surface with a decrease in sebaceous secretion or in depth with a lack of covalent bonds between the lipids and the cuticular cells. The result is a porous cuticle, a dull, rough hair that is difficult to untangle and breaks easily. The aim of this study was to evaluate properties of oils extracted from Cocos nucifera and Elaeis guineensis intended for the formulation of shampoos for black hair. Physicochemical and rheological analyses were carried out. Both oils showed a refractive index of 1.45 and melting points of 28 °C and 30 °C for coconut oil and palm kernel oil, respectively. The relative densities, moisture contents, saponification indexes, peroxide values, unsaponifiable matter contents, para-anisidine values were relatively similar while iodine and acid values were different. Both oils are rich in lauric, oleic and linoleic acids. These oils exhibited a Newtonian behavior and a dominant elastic nature after their melting temperature in the study conditions. They could constitute active ingredients for the formulation of shampoo for black hair in view of their different characteristics.Keywords: Physico-chemical analyses, rheological parameters, Cocos nucifera oil, Elaeis guineensis oil

Structures spécifiques des peuplements de rongeurs d’agro-écosystèmes et d’écosystèmes «naturels» de la Guadeloupe et de la Martinique

The Muridae rodent community of Guadeloupe and Martinique (French West Indies) includes 3 alien species : the Ship Rat (Rattus rattus), the Norwegian Rat (Rattus norvégiens) and the House Mouse (Mus musculus). A 26,740 trap-night effort conducted under standardized sampling methods showed a strong heterogeneity of the species frequency distribution among 4 agricultural ecosystems (sugar cane, banana, cassava and watermelon) and 3 “natural” ones (tropical rain forest and islands or islets covered either totally or partially by a dry vegetation). A second step of the analysis conducted at a smaller space scale, from the surrounding ecosystems of the cultivated areas to the inside of these ones, gave the same result. The House Mouse constituted the majority of the captures in the agricultural ecosystems (56% for the total and 84% for sugar cane specifically). This species is well represented inside the cultivated area and poorly outside. The Ship Rat is well represented in the “savannah” and “thorn-scrub”, and in tropical rain forest, habitats that surround sugar cane and banana fields respectively. Statistically less numerous than the others, the Norwegian Rat was nevertheless well represented in the cultivated area devoted to watermelon and cassava, and concentrated in the field margins. The build-up and the optimisation of strategies for controlling the alien rodents in tropical islands are discussed in relation to these results. The build-up of sampling strategies to evaluate epidemiological and environmental risks due to these alien rodents is also discussed. This last discussion was done in the light of a new result showing that 57% of sampled Guadeloupe House Mice hosted Leptospira interrogans on their kidneys.Le peuplement de rongeurs muridés de la Guadeloupe et de la Martinique est constitué de 3 espèces allochtones, le Rat noir (Rattus rattus), le Rat surmulot (Rattus norvegicus) et la Souris domestique (Mus musculus). Un effort d’échantillonnage standardisé de 26 740 nuits-pièges a permis de mettre en évidence une grande hétérogénéité de la distribution de ces espèces au sein d’un ensemble de 4 agro-écosystèmes (canne à sucre, banane, manioc et pastèque) et de 3 écosystèmes “naturels” (forêt tropicale humide et 2 types d’îles ou îlots à végétation xérophile). Une analyse des résultats, conduite à une échelle spatiale plus fine, depuis les milieux encaissant les parcelles cultivées jusque dans celles-ci, aboutit à la même conclusion. Les Souris domestiques constituent la majorité des captures réalisées sur l’ensemble des agro-écosystèmes étudiés (56 % pour l’ensemble et jusqu’à 84 % pour les agro-écosystèmes canniers). L’espèce est fortement représentée au sein des parcelles cultivées et faiblement dans les milieux encaissants. Le Rat noir est fortement représenté dans les “savanes” et formations d’épineux d’une part, et la forêt tropicale humide d’autre part, ces milieux constituant respectivement l’environnement immédiat des champs de canne et des bananeraies. Le Surmulot,Pascal Michel, Lorvelec Olivier, Borel Gaétan, Rosine Armand. Structures spécifiques des peuplements de rongeurs d’agro-écosystèmes et d’écosystèmes «naturels» de la Guadeloupe et de la Martinique . In: Revue d'Écologie (La Terre et La Vie), tome 59, n°1-2, 2004. pp. 283-292

Resistance to anticoagulant rodenticides in Martinique could lead to inefficient rodent control in a context of endemic leptospirosis

Leptospirosis is a re-emergent worldwide zoonosis. It is endemic in Martinique where transmission conditions are favourable. Humans are usually infected through contact with water contaminated with urine of rodents. Recent human leptospirosis outbreaks in Martinique require today effective rodent management to prevent leptospirosis transmission. Nowadays, use of anticoagulant rodenticides (AR) is the main method implemented to control rodent populations. Nevertheless, intensive use of these AR has selected worldwide manyVKORC1-based resistant rodent strains to AR. Our aim was to characterize the sensitivity of Martinique commensal rodents to AR to better prevent leptospirosis transmission. Resistance of house mice to first-generation and in rare cases even to second-generation ARs were clearly demonstrated in Martinique with the detection of theY139C mutation with a very high allelic frequency of 40% and the A26T/Y139C double-mutation with an allelic frequency of 0.9%. In black rat, the most prevalent rodent in Martinique, 3 new Vkorcl coding mutations were detected, the H68N, A115T and 5149N mutations associated with moderate resistance to first generation AR. Therefore, rodent management in Martinique must be carried carefully to avoid resistance diffusion and maintain long-term effective rodent management, to be able to efficiently prevent leptospirosis transmission

COMPARATIVE STUDY OF THREE EXTRACTION PROCESSES OF SECONDARY METABOLITES FROM LEAVES AND STEMS OF ARTEMISIA ANNUA (Asteraceae)

Introduction: Artemisia annua (Asteraceae) is a plant widely used to treat diseases including malaria. Manipulation conditions and treatment of plant influence physico-chemical characteristics and composition, so that objective of this work was to examine extraction processes in order to identify the best process that leads to obtain extracts with optimal pharmacotechnical characteristics and phytochemical properties for drugs formulation. Methods: From raw powder resulting by spraying stems and leaves of Artemisia annua, 3 types of extracts were obtained; a dry infused, a dry hydro-ethanolic macerate and a freeze-dried infused. These different extracts were then characterized on physico-chemical, phyto-chemical and microbiological levels in order to compare them. Results: Freeze-dried infused exhibited the highest extraction yield followed by dry hydro-alcoholic macerate and dry infused with extraction percentages respectively of 11.7 ±0.3%, 8.4 ± 0.4% and 6.8 ± 0.3%. Powders tested were fine and had a diameter varying from 0-2.75 µm with a D 50 <125 µm). Lyophilisate had a porphyritic morphology while macerate and infused had respectively a sticky and crystalline appearance. All powders were microbiologically clean and hydro-ethanolic macerate was qualitatively the richest extract in phytochemicals. Dosage of artemisinin by HPLC showed that freeze-dried infused had the highest concentration of artemisinin (3322.5 +/- 0.637 µg/mL) compared to dry infused (1308.9 +/- 0.105 µg/mL), dry macerate (1296.2 +/- 0.251 μg/mL) and raw powder (2190.8 +/- 0.48 μg/mL). In contrast, phytochemical constituents such as flavonoids were more abundant in macerate than dry infused respectively at 28.7 +/- 0.215 mg EQ/g and 11.4 +/- 0.16 mg EQ/g. Flavonoids concentration were not quantifiable in lyophilizate. Conclusion: Lyophilization should be the best pharmaceutical processes which permit to obtain a high concentration of artemisinin, the best yield of extract, good moisture content and extract powder highly recommended for herbal galenic preparation forms used to fight malaria diseases

COMPARATIVE STUDY OF THREE EXTRACTION PROCESSES OF SECONDARY METABOLITES FROM LEAVES AND STEMS OF ARTEMISIA ANNUA (Asteraceae)

Introduction: Artemisia annua (Asteraceae) is a plant widely used to treat diseases including malaria. Manipulation conditions and treatment of plant influence physico-chemical characteristics and composition, so that objective of this work was to examine extraction processes in order to identify the best process that leads to obtain extracts with optimal pharmacotechnical characteristics and phytochemical properties for drugs formulation. Methods: From raw powder resulting by spraying stems and leaves of Artemisia annua, 3 types of extracts were obtained; a dry infused, a dry hydro-ethanolic macerate and a freeze-dried infused. These different extracts were then characterized on physico-chemical, phyto-chemical and microbiological levels in order to compare them. Results: Freeze-dried infused exhibited the highest extraction yield followed by dry hydro-alcoholic macerate and dry infused with extraction percentages respectively of 11.7 ±0.3%, 8.4 ± 0.4% and 6.8 ± 0.3%. Powders tested were fine and had a diameter varying from 0-2.75 µm with a D 50 <125 µm). Lyophilisate had a porphyritic morphology while macerate and infused had respectively a sticky and crystalline appearance. All powders were microbiologically clean and hydro-ethanolic macerate was qualitatively the richest extract in phytochemicals. Dosage of artemisinin by HPLC showed that freeze-dried infused had the highest concentration of artemisinin (3322.5 +/- 0.637 µg/mL) compared to dry infused (1308.9 +/- 0.105 µg/mL), dry macerate (1296.2 +/- 0.251 μg/mL) and raw powder (2190.8 +/- 0.48 μg/mL). In contrast, phytochemical constituents such as flavonoids were more abundant in macerate than dry infused respectively at 28.7 +/- 0.215 mg EQ/g and 11.4 +/- 0.16 mg EQ/g. Flavonoids concentration were not quantifiable in lyophilizate. Conclusion: Lyophilization should be the best pharmaceutical processes which permit to obtain a high concentration of artemisinin, the best yield of extract, good moisture content and extract powder highly recommended for herbal galenic preparation forms used to fight malaria diseases

C33 Etude comparative de microparticules à base de pectine de Mangifera indica L. (Anacardiaceae) versus la pectine synthétique

Introduction : La pectine est un polysaccharide retrouvé dans la paroi de nombreuses cellules végétales, notamment dans les fruits mûrs. Elle possède d’excellentes propriétés gélifiantes qui en font un ingrédient particulier dans l’industrie alimentaire et pharmaceutique. Elle est obtenue également par synthèse, donnant lieu à la pectine synthétique. Dès lors, les propriétés de ces deux sources de pectine seraient-elles identiques ? L’objectif de notre travail était de comparer des formulations de microparticules d’acide salicylique à partir de pectine naturelle de Mangifera indica L. et de pectine synthétique. Méthodes : La gélification ionique a été utilisée pour la fabrication des microparticules. Pour la préparation 3% de pectine naturelle contre 2% de pectine synthétique ont été utilisé dans du tampon citrate à pH 5 avec du chlorure de calcium (CaCl2) à 0,2%. La solution de réticulation était du CaCl2 à 10%. Les microparticules obtenues ont été caractérisées sur le plan macroscopique par la vérification de la couleur et de la forme. La taille des particules a été déterminée au microscope optique permettant de calculer les déciles. Enfin les différents taux d’encapsulation ainsi que les rendements d’encapsulation ont été déterminés. Résultats : Les microparticules obtenues avec la pectine naturelle étaient de couleur brune et de forme aplaties, celles avec la pectine synthétique étaient de couleur blanche plus ou moins arrondies. La pectine   naturelle donnait des particules de taille variant de 87 à 190 mm avec une moyenne de 137,70 mm et un rapport interdecile de 1,66. Quant à la pectine synthétique, les tailles des particules étaient comprises entre 58 et 116 mm avec une moyenne de 85,19 mm et un rapport interdecile de 1,55. Le taux d’encapsulation avec la pectine naturelle de Mangifera indica L. était de 6,08% avec un rendement d’encapsulation de 78,5%. En ce qui concerne la pectine synthétique, elle a donné un taux d’encapsulation de 17,72% et un rendement d’encapsulation de 88%. Conclusion : Des microparticules ont pu être formulées avec la pectine naturelle de Mangifera indica L. Cependant, la pectine synthétique a donné de meilleurs résultats de formulation et a pu encapsuler plus de principe actif par rapport à la pectine naturelle

Memoires de 68

En annexe, revue Materiaux pour l'histoire de notre temps, 1991, n.24SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : AR 15085 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

A global compilation of diatom silica oxygen isotope records from lake sediment – trends, and implications for climate reconstruction

International audienceOxygen isotopes in biogenic silica (δ18OBSi) from lake sediments allow for quantitative reconstruction of past hydroclimate and proxy–model comparison in terrestrial environments. The signals of individual records have been attributed to different factors, such as air temperature (Tair), atmospheric circulation patterns, hydrological changes and lake evaporation. While every lake will have its own set of drivers of d18O, here we explore the extent to which regional or even global signals emerge from a series of palaeoenvironmental records. For this purpose, we have identified and compiled 71 down–core records published to date and complemented these datasets with additional lake basin parameters (e.g. lake water residence time and catchment size) to best characterize the signal properties. Records feature widely different temporal coverage and resolution ranging from decadal–scale records covering the last 150 years to records with multi–millennial scale resolution spanning glacial–interglacial cycles. Best coverage in number of records (N = 37) and datapoints (N = 2112) is available for northern hemispheric (NH) extra–tropic regions throughout the Holocene (corresponding to Marine Isotope Stage 1; MIS 1). To address the different variabilities and temporal offsets, records were brought to a common temporal resolution by binning and subsequently filtered for hydrologically open lakes with lake water residence times 45° N) lakes, we find common δ18OBSi patterns during both the Holocene and the Common Era and maxima and minima corresponding to known climate episodes such as the Holocene Thermal Maximum (HTM), Neoglacial Cooling, Medieval Climate Anomaly (MCA) and the Little Ice Age (LIA). These patterns are in line with long–term Tair changes supported by previously published climate reconstructions from other archives as well as Holocene summer insolation changes. In conclusion, oxygen isotope records from NH extratopic lake sediments feature a common climate signal at centennial (for CE) and millennial (for Holocene) time scales despite stemming from different lakes in different geographic locations and constitute a valuable proxy for past climate reconstructions

A global compilation of diatom silica oxygen isotope records from lake sediment: additional information on the lakes and sites corresponding to the records

Oxygen isotopes in biogenic silica (δ18O BSi) from lake sediments allow for quantitative reconstruction of past hydroclimate and proxy–model comparison in terrestrial environments. The signals of individual records have been attributed to different factors, such as air temperature (T air ), atmospheric circulation patterns, hydrological changes and lake evaporation. Here, we provide 55 composite down–core records published to date and complemented with additional lake basin parameters (e.g. lake water residence time and catchment size) to best characterize the signal properties. Records feature widely different temporal coverage and resolution ranging from decadal–scale records covering the last 150 years to records with multi–millennial scale resolution spanning glacial–interglacial cycles. Best coverage in number of records (N=37) and datapoints (N=2112) is available for northern hemispheric (NH) extra–tropic regions throughout the Holocene (corresponding to Marine Isotope Stage 1; MIS 1)