21 research outputs found

    Etude de synergie des effets chimiques et biologiques des lipides de réserve et des huiles essentielles des fruits et graines saisonniers de la sous-région Afrique Centrale

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    La composition en huiles essentielles et en lipides de rĂ©serve des graines et fruits saisonniers de quatre espĂšces vĂ©gĂ©tales d origine congolaise (Aframomum stipulatum (Gagnep) K. Schum, Aframomum giganteum (Oliv. and Hand) K. Schum, Spondias mombin L. et Nephelium lappaceum L.), a Ă©tĂ© dĂ©terminĂ©e par l utilisation du couplage chromatographie en phase gazeuse/spectromĂ©trie de masse. Les rĂ©sultats obtenus ont permis de comprendre la bioaccumulation des huiles essentielles et des lipides de rĂ©serve dans les organes des diffĂ©rentes espĂšces. Dans le cas des espĂšces du genre Aframomum, les graines et les coques de fruits sont sources Ă  la fois des huiles essentielles et des lipides de rĂ©serve. Les huiles essentielles des graines des deux espĂšces du genre Aframomun sont riches en composĂ©s monoterpĂ©niques hydrocarbonĂ©s et oxygĂ©nĂ©s (b-pinĂšne, 1,8-cinĂ©ole, phellandrĂšne) avec des taux non nĂ©gligeables de sesquiterpĂšnes (a-sĂ©linĂšne et b-caryophyllĂšne). Les huiles essentielles des coques des deux mĂȘmes espĂšces se rĂ©vĂšlent plus riches en monoterpĂ©nes oxygĂ©nĂ©s que celles des graines avec des composĂ©s trĂšs caractĂ©ristiques (b-pinĂšne, 1,8-cineole, linalool pour A. giganteum et b-pinĂšne, terpinĂ©ol, 1,8-cinĂ©ole pour A. stipulatum). On note dans les deux espĂšces, en dĂ©pit des procĂ©dĂ©s unitaires diffĂ©rents utilisĂ©s, la prĂ©sence de lipides de rĂ©serve avec un profil acides gras du type palmitique-linolĂ©ique. Seuls les lipides de rĂ©serve ont Ă©tĂ© caractĂ©risĂ©s dans Spondias mombin L. et Nephelium lappaceum L.. Les diffĂ©rentes parties du fruit de Spondias mombin sont dominĂ©es, comme dans le cas des Aframomum, par la prĂ©sence des acides palmitique-linolĂ©ique avec une prĂ©sence marquĂ©e de l hentriacontane dans l huile de peaux de fruits. L huile d amande de Nephelium lappaceum se distingue par sa richesse en acide arachidique C20:0 et acide 11- eicosĂ©noĂŻque C20:1. Les quatre espĂšces prĂ©sentent un apport en phytostĂ©rols et en tocophĂ©rols. Des essais prometteurs de formulation de phytoproduits ont Ă©tĂ© rĂ©alisĂ©s avec des mĂ©langes de tensioactifs, des a-monoglycĂ©rides et des huiles essentielles de graines de A. giganteum. Les activitĂ©s antimicrobienne, anticancĂ©reuse, antipaludique et anti-radicalaire ont Ă©tĂ© Ă©valuĂ©es sur les extraits d huiles essentielles et sur les lipides de rĂ©serve ainsi que sur les analogues synthĂ©tiques de lipides pris seuls ou en combinaison. Les rĂ©sultats obtenus sont prometteursThe composition of essential oils and fat of seasonal fruits and seeds of four plant species from the Congo (Aframomum stipulatum (Gagnep) K. Schum, Aframomum giganteum (Oliv. and Hand) K. Schum, Spondias mombin L. and Nephelium lappaceum L.), was determined by the combined use of mass spectrometry and gas chromatography. The results were used for understanding the bio-accumulation of essential oils and the storage of lipids in the organs of different species. In the case of the genus Aframomum, seeds and fruit shells are both sources of essential oils and fat. Seeds essential oils of the two species of Aframomun were rich in hydrocarbon and oxygenated monoterpene compounds such as b-pinene, 1,8-cineole, phellandrene, with significant levels of sesquiterpenes (a-selinene and b-caryophyllene). The shells essential oils of the same two species appear to be more rich in oxygenated monoterpenes than seeds, with a large structural features (b-pinene, 1,8-cineole, linalool for A. giganteum and b-pinene, terpineol, 1.8 -cineole for A. stipulatum). It is notified in both species that despite the different unit processes used, the presence of lipid with a fatty acid profile of the type palmitic-linoleic. Only lipids have been characterized from Spondias mombin L. and Nephelium lappaceum L.. The different parts of the fruit of Spondias mombin are dominated, like Aframomum, by the presence of palmitic-linoleic with a large presence of hentriacontane in the oil fruit skins. The kernel oil Nephelium lappaceum is distinguished by its wealth of arachidic acid C20:0 and 11-eicosĂ©noĂŻc acid C20:1. The four species contained in phytosterols and tocopherols. Testing promising formulation of herbal products were made with mixtures of surfactants, a-monoglycerides and essential oils from seeds of A. giganteum. Antimicrobial, anticancer, antimalarial and anti-radical activities were evaluated on the essential oils on the lipid as well as on the synthetic analogs of lipid alone or in combination. The results are promisingTOULOUSE-INP (315552154) / SudocSudocFranceF

    Variation in the chemical composition of the essential oils of different organs of domesticated Lippia multiflora Moldenke

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    The essential oils from the different organs of wild and domesticated Lippia multiflora Moldenke, analysed by GPC-FID and GPC-MS, were rich in monoterpenes. These made up 95.0, 94.0, 82.5 and 61.0% of oils from leaves, flowers, stems and roots, respectively, with a predominance of aromatic monoterpenes: p-cymene, thymol, carvacrol and their acetates together made up 44.0 - 74.0% of the oils, along with b-caryophyllene and its oxide (3.0 - 8.4%). Oils from roots differed from those of flowers, leaves and stems by a higher proportion of b-caryophyllene and its oxide (16.0%), and the absence of p-cymene g-terpinene represented respectively, 6.3 - 18.0 and 0.7 - 11.4% of the oils from the other organs. (Z)-ÎČ-Ocimene, identified in the oils from flowers (nearly 10%) was absent from oils of leaves, stems and roots. Oils of stems and roots contained very small amounts of hexadecanoĂŻc acid, b-eudesmol, isocaryophyllene and phytol, none of which had previously been reported in oils from the Congo.Key words: Lippia multiflora Moldenke, organs, essential oil, chemical composition

    Evaluation De La QualitĂ© Physico-Chimique et Microbiologique Des Eaux De Puits ConsommĂ©es Dans Le Quartier KombĂ© À Brazzaville

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    La prĂ©sente Ă©tude vise Ă  Ă©valuer la qualitĂ© physico-chimique et microbiologique des eaux de puits consommĂ©es dans le quartier KombĂ© Ă  Brazzaville. Quatre puits ont Ă©tĂ© identifiĂ©s et caractĂ©risĂ©s. La caractĂ©risation a montrĂ© trois puits Ă©quipĂ©s des mĂȘmes systĂšmes de protection et de remontĂ©e d'eau et, un seul point de prĂ©lĂšvement diffĂšre des autres par le systĂšme de remontĂ©e d'eau. Trente-trois paramĂštres physico-chimiques et neuf paramĂštres microbiologiques ont Ă©tĂ© Ă©valuĂ©s par des mĂ©thodes normĂ©es et rĂ©fĂ©rencĂ©es. Les rĂ©sultats obtenus rĂ©vĂšlent du point de vue physico-chimique que, les eaux de puits Ă©tudiĂ©es sont faiblement minĂ©ralisĂ©es et tous les paramĂštres physico-chimiques rĂ©pondent aux normes de l'OMS, exceptĂ© le pH, la concentration des ions cadmium, chrome, phosphate ainsi que de la silice dans certains cas. La projection des points d’eau sur le diagramme de Piper montre deux familles chimiques : les eaux chlorurĂ©es sodique et potassique et les eaux bicarbonatĂ©es sodique et potassique. Par contre, les eaux consommĂ©es par la population de quartier KombĂ© sont fortement chargĂ©es en E.coli, salmonella et shigella, coliformes totaux, pseudomonas aeruginosa, germes totaux, staphylocoques et, levures et moisissures et sont impropres Ă  la consommation humaine. Avant leur consommation ces eaux doivent subir quelques traitements prĂ©liminaires comme la correction du pH Ă  la chaux et la dĂ©sinfection Ă  l’hypochlorite de sodium.   This study aims to assess the physico-chemical and microbiological quality of well water consumed in the KombĂ© district in Brazzaville. Four wells have been identified and characterized. The characterization showed three wells equipped with the same protection and upwelling systems and only one sampling point differs from the others by the upwelling system. Thirty-three physico-chemical parameters and nine microbiological parameters were evaluated by standardized and referenced methods. The results obtained reveal from the physico-chemical point of view that the waters of the wells studied are weakly mineralized and all the physico-chemical parameters meet WHO standards, except the pH, the concentration of cadmium, chromium and phosphate ions as well as than silica in some cases. The projection of the water points on the Piper diagram shows two chemical families: sodium and potassium chlorinated waters and sodium and potassium bicarbonate waters. On the other hand, the water consumed by the population of the KombĂ© district is heavily loaded with E.coli, salmonella and shigella, total coliforms, pseudomonas aeruginosa, total germs, staphylococci and yeasts and molds and is unfit for human consumption. Before being consumed, this water must undergo some preliminary treatments such as pH correction with lime and disinfection with sodium hypochlorite

    Evaluation de la Qualité Physico-Chimique et Microbiologique des eaux de Puits Consommées dans le Quartier Kombé à Brazzaville

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    Naturellement, les eaux souterraines sont potables de façon gĂ©nĂ©rale et devraient ĂȘtre consommĂ©es sans aucun traitement prĂ©alable. Malheureusement, ces eaux sont soumises actuellement Ă  une forte pression anthropique. Cette Ă©tude vise d’évaluer la qualitĂ© physico-chimique et microbiologique des eaux de puits consommĂ©es dans le quartier KombĂ© Ă  Brazzaville. Quatre puits ont Ă©tĂ© identifiĂ©s et caractĂ©risĂ©s. La caractĂ©risation a montrĂ© trois puits Ă©quipĂ©s des mĂȘmes systĂšmes de protection et de remontĂ©e d'eau et, un seul point de prĂ©lĂšvement diffĂšre des autres par le systĂšme de remontĂ©e d'eau. Trente-trois paramĂštres physico-chimiques et neuf paramĂštres microbiologiques ont Ă©tĂ© Ă©valuĂ©s par des mĂ©thodes normĂ©es et rĂ©fĂ©rencĂ©es. Les rĂ©sultats obtenus rĂ©vĂšlent du point de vue physico-chimique que, les eaux de puits Ă©tudiĂ©es sont faiblement minĂ©ralisĂ©es et tous les paramĂštres physicochimiques rĂ©pondent aux normes de l'OMS, exceptĂ© le pH, la concentration des ions cadmium, chrome, phosphate ainsi que de la silice dans certains cas. Une seule famille chimique est mise en Ă©vidence : les eaux chlorurĂ©es sodique et potassique. Malheureusement, ces eaux sont fortement chargĂ©es en Escherichia. coli, Salmonella et Shigella, coliformes totaux, Pseudomonas aeruginosa, germes totaux, staphylocoques, levures et moisissures. Elles sont impropres Ă  la consommation humaine et doivent subir quelques traitements prĂ©liminaires comme la correction du pH Ă  la chaux et la dĂ©sinfection Ă  l’hypochlorite de sodium. Naturally, groundwater is generally drinkable and should be consumed without any prior treatment. Unfortunately, these waters are currently subject to strong anthropogenic pressure. This study aims to evaluate the physicochemical and microbiological quality of well water consumed in the KombĂ© district of Brazzaville. Four wells were identified and characterized. The characterization showed three wells equipped with the same protection and water rise systems and only one sampling point differed from the others by the water rise system. Thirty-three physicochemical parameters and nine microbiological parameters were evaluated using standardized and referenced methods. The results obtained reveal from the physicochemical point of view that the well water studied is poorly mineralized and all the physicochemical parameters meet WHO standards, except pH, the concentration of cadmium, chromium, phosphate ions as well as than silica in certain cases. Only one chemical family is highlighted: sodium and potassium chloride waters. Unfortunately, these waters are heavily loaded with Escherichia. coli, Salmonella and Shigella, total coliforms, Pseudomonas aeruginosa, total germs, staphylococci, yeasts and molds. They are unfit for human consumption and must undergo some preliminary treatments such as pH correction with lime and disinfection with sodium hypochlorite

    Evaluation De La QualitĂ© Physico-Chimique et Microbiologique Des Eaux De Puits ConsommĂ©es Dans Le Quartier KombĂ© À Brazzaville

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    La prĂ©sente Ă©tude vise Ă  Ă©valuer la qualitĂ© physico-chimique et microbiologique des eaux de puits consommĂ©es dans le quartier KombĂ© Ă  Brazzaville. Quatre puits ont Ă©tĂ© identifiĂ©s et caractĂ©risĂ©s. La caractĂ©risation a montrĂ© trois puits Ă©quipĂ©s des mĂȘmes systĂšmes de protection et de remontĂ©e d'eau et, un seul point de prĂ©lĂšvement diffĂšre des autres par le systĂšme de remontĂ©e d'eau. Trente-trois paramĂštres physico-chimiques et neuf paramĂštres microbiologiques ont Ă©tĂ© Ă©valuĂ©s par des mĂ©thodes normĂ©es et rĂ©fĂ©rencĂ©es. Les rĂ©sultats obtenus rĂ©vĂšlent du point de vue physico-chimique que, les eaux de puits Ă©tudiĂ©es sont faiblement minĂ©ralisĂ©es et tous les paramĂštres physico-chimiques rĂ©pondent aux normes de l'OMS, exceptĂ© le pH, la concentration des ions cadmium, chrome, phosphate ainsi que de la silice dans certains cas. La projection des points d’eau sur le diagramme de Piper montre deux familles chimiques : les eaux chlorurĂ©es sodique et potassique et les eaux bicarbonatĂ©es sodique et potassique. Par contre, les eaux consommĂ©es par la population de quartier KombĂ© sont fortement chargĂ©es en E.coli, salmonella et shigella, coliformes totaux, pseudomonas aeruginosa, germes totaux, staphylocoques et, levures et moisissures et sont impropres Ă  la consommation humaine. Avant leur consommation ces eaux doivent subir quelques traitements prĂ©liminaires comme la correction du pH Ă  la chaux et la dĂ©sinfection Ă  l’hypochlorite de sodium.   This study aims to assess the physico-chemical and microbiological quality of well water consumed in the KombĂ© district in Brazzaville. Four wells have been identified and characterized. The characterization showed three wells equipped with the same protection and upwelling systems and only one sampling point differs from the others by the upwelling system. Thirty-three physico-chemical parameters and nine microbiological parameters were evaluated by standardized and referenced methods. The results obtained reveal from the physico-chemical point of view that the waters of the wells studied are weakly mineralized and all the physico-chemical parameters meet WHO standards, except the pH, the concentration of cadmium, chromium and phosphate ions as well as than silica in some cases. The projection of the water points on the Piper diagram shows two chemical families: sodium and potassium chlorinated waters and sodium and potassium bicarbonate waters. On the other hand, the water consumed by the population of the KombĂ© district is heavily loaded with E.coli, salmonella and shigella, total coliforms, pseudomonas aeruginosa, total germs, staphylococci and yeasts and molds and is unfit for human consumption. Before being consumed, this water must undergo some preliminary treatments such as pH correction with lime and disinfection with sodium hypochlorite

    ActivitĂ©s AntiprolifĂ©rative et Antiradicalaire d’extraits Aqueux de Quatre Plantes MĂ©dicinales Congolaises

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    Le but de ce travail est d’évaluer les propriĂ©tĂ©s antiprolifĂ©rative et antiradicalaire des extraits aqueux de quatre plantes mĂ©dicinales congolaises dont Morinda lucida, Klainedoxa gabonensis, Tephrosia vogelii et Nauclea latifolia. L’activitĂ© antiprolifĂ©rative de l’extrait aqueux de chacune des quatre espĂšces a Ă©tĂ© Ă©valuĂ©e in vitro sur une lignĂ©e cellulaire cancĂ©reuse (U87-MG) et une lignĂ©e cellulaire normale (Hek-293) en utilisant le test MTT. L’activitĂ© antiradicalaire a Ă©tĂ© Ă©valuĂ©e en mesurant la capacitĂ© de piĂ©geage du radical DPPH. Des analyses phytochimiques des extraits ont Ă©tĂ© rĂ©alisĂ©es par chromatographie sur couche mince et par HPLC-PDA. Les extraits aqueux de Klainedoxa gabonenis et de Tephrosia vogelii ont montrĂ© une activitĂ© antiprolifĂ©rative contre les cellules cancĂ©reuses U87-MG avec des valeurs de CI50 infĂ©rieures Ă  90 ÎŒg/ml. L’extrait aqueux de Klainedoxa gabonenis a montrĂ© Ă©galement une activitĂ© antiradicalaire remarquable (CI50 = 4 ± 0,73 ÎŒg/ml) .En plus, le traitement des cellules cancĂ©reuses U87-MG Ă  la fois par l’extrait aqueux de Klainedoxa gabonensis (100 ÎŒg/ml) et par un inhibiteur de la protĂ©ine MEK (1ÎŒM) provoque une suppression totale de la prolifĂ©ration des cellules U87-MG (glioblastome). L’analyse en HPLC–PDA de l’extrait aqueux Klainedoxa gabonenis a montrĂ© la prĂ©sence des composĂ©s de type acide gallique (41, 9 %) et quercĂ©tine (2,17 %). Notre Ă©tude a permis d’identifier deux plantes mĂ©dicinales aux propriĂ©tĂ©s antiprolifĂ©ratives parmi les quatre plantes mĂ©dicinales congolaises Ă©valuĂ©es dont une possĂ©dant Ă  la fois les propriĂ©tĂ©s antiprolifĂ©rative et antiradicalaire. The purpose of this work is to evaluate antiprolifertive and DPPH radical scavenging activities of aqueous extracts from Morinda lucida Smith, Klainedoxa gabonensis Pierre ex Engl, Tephrosia vogelii Hook f and Nauclea latifolia Sm. The antiproliferative activity of the aqueous extract of each of the four species was evaluated in vitro on a cancer cell line (U87-MG) and a normal cell line (Hek-293) using the MTT assay. The antiradicalar activity was evaluated by measuring the scavenger capacity of the DPPH radical. Phytochemical analyzes of the extract were performed by thin layer chromatography and HPLC-PDA. The aqueous extracts of Klainedoxa gabonenis and Tephrosia vogelii showed antiproliferative activity against U87-MG cancer cells with IC50 values below 90 ÎŒg / ml. The aqueous extract of Klainedoxa gabonenis also showed remarkable antiradical activity (IC50 = 4± 0,73 ÎŒg/ml). In addition, the treatment of U87-MG cancer cells by both the aqueous extract of Klainedoxa gabonensis (100 ÎŒg / ml) and by an MEK protein inhibitor (1 ÎŒM) causes a total suppression of U87-cell proliferation. MG (glioblastoma). HPLC-PDA analysis of the aqueous extract Klainedoxa gabonenis showed the presence of gallic acid compounds (41.9%) and Quercetin (2.17%).: Our study identified two medicinal plants with antiproliferative properties among the four Congolese herbal medicines evaluated, one with both anti-proliferative and antiradical properties

    IN VITRO EVALUATION OF ANTIPLASMODIAL ACTIVITY OF EXTRACTS OF ACANTHOSPERMUM HISPIDUM DC (ASTERACEAE) AND FICUS THONNINGII BLUME (MORACEAE), TWO PLANTS USED IN TRADITIONAL MEDICINE IN THE REPUBLIC OF CONGO.

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    The aim of this study was to evaluate extracts from two medicinal plants, Acanthospermum hispidum and Ficus thonningii, used in traditional medicine in Congo Brazzaville, for in vitro antiplasmodial activities against two laboratory strains of Plasmodium falciparum: the chloroquine sensitive 3D7 and the chloroquine resistant Dd2. ELISA HRP2 assay was used to evaluate the in vitro inhibitory activity of the extracts alone or in combination with chloroquine. Cytotoxicity was assessed on human HeLa cell line and reflected by the selectivity index. Methanolic extract of Acanthospermum hispidum exhibited a strong and a moderate inhibitory activity on the growth of Dd2 and 3D7 at 2.8 ”g/ml and 9.2 ”g/ml concentrations respectively with a selectivity index >10. The combination of the most active extract (methanolic extract of Acanthospermum hispidum) with chloroquine showed a synergistic interaction on both strains. The good selectivity index of Acanthospermum hispidum on HeLa cells reflects the safety of this plant. Extracts from Ficus thonningii did not show any promising antiplasmodial activity on both 3D7 and Dd2. Except the methanolic extract which exhibited a slight antiplasmodial activity with inhibitory concentration and selectivity index corresponding to 9.61 ”g/ml and 11.16 respectively. Methanolic extract of Acanthospermum hispidum exhibited moderate to high inhibitory activity on 3D7 and Dd2 laboratory strains and a synergistic antimalarial effect when combined with chloroquine. Ficus thonningii seems to have no antimalarial activity. Phytochemical analysis, in vivo investigations using animal models and later clinical trials in collaboration with traditional practitioners are necessary to clarify the potential antimalarial activity of both plants

    Impact of Waste Management on Surface Water and Soil Pollution on the Right Bank of the Congo River in the Brazzaville Agglomeration (Republic of Congo)

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    Situated on the right bank of the Pool Malébo, in the Congo River basin, the city of Brazzaville is rich in potential water resources. This resource is being polluted by human practices that are deteriorating the quality of the soil and, consequently, the quality of the water. The aim of this study is therefore to list the activities carried out by the population around watercourses in order to get an idea of how waste is managed and its impact on water and soil quality. The survey sample was selected on the basis of zones of influence located between 250 m and 750 m around watercourses. The survey form was drawn up using Sphinx Plus2-Edition Lexica-V5. The data from the surveys was entered into the same software, then transferred to Excel for processing in order to produce the graphs. 880 people were surveyed, the most dominant age group being between 25 and 48 years old, i.e. a rate of 66%; the female sex being the most representative with a rate of 54%. The average age of the respondents was lower secondary school, and they were generally employed in the private sector. Commercial activities (restaurants/bars, pharmacies, grocery stores/butchers, markets, etc.) are the most common economic activity, with a rate of around 70%; 59% of these activities are located close to or very close to the watercourse (750 - 1000 m). The activities that contribute to soil degradation, and consequently water degradation, in the city of Brazzaville are: 59% the dumping of household waste and/or wastewater on the ground and 32% uncontrolled urbanization. The study shows that soil and water pollution in Brazzaville is caused by poor management of household waste and uncontrolled urbanization

    CaractĂ©risation Phytochimique et ActivitĂ© Larvicide d’extraits Bruts de Plantes Issues de la PharmacopĂ©e Traditionnelle du Niger sur les Larves d’Anopheles gambiae S.L.

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    In the preventive fight against malaria, natural products are considered better because they are biodegradable and therefore more respectful of the environment and the ecosystem. In the framework of the research of new insecticidal molecules, the present study concerns, the phytochemical screening and the evaluation of the larvicidal activity of the extracts (aqueous and methanolic) of 26 plants on the larvae of Anopheles gambiae sl. been carried out according to a WHO protocol (1985). The phytochemical profile of the plants was determined according to the standard methods of characterization (color reactions). High larvicidal activity against Anopheles gambiae larvae after 24 h and then 48 h exposure was observed. Crotalaria podocarpa, Momordica balsamina, Xeromphis nilotica and Senna occidentalis showed a 100% mortality rate after 24 hours of exposure. The larvicidal activity is much more important after 48 hours. A 100% mortality was observed with Senna occidentalis, Momordica balsamina, Ocimum basilicum, Citrus sinensis, Striga hermontheca, Xeromphis. nilotica, Crotalaria podocarpa, Diospyros mespiliformis, Cymbopogon citratus, Cleome viscosa and Combretum micrantum. Poor larvicidal activity was observed on the one hand with the methanolic extracts of Crotalaria podocarpa and Aloe vera and on the other with the aqueous extracts of Citrus sinensis, Ocimum basilicum and Aloe vera. Phytochemicalscreening revealed the presence of five major groups of compounds, including saponosides, terpenes sterols, flavonoids, tannins and alkaloids, which are also present in the aqueous and methanolic extracts of the various plant samples. These chemical groups could justify the traditional use of these plants.Dans la lutte prĂ©ventive contre le paludisme, les produits naturels sont considĂ©rĂ©s comme meilleurs car biodĂ©gradables et donc plus respectueux de l’environnement et de le Ă©cosystĂšme. Dans le cadre de la recherche des nouvelles molĂ©cules insecticides, la prĂ©sente Ă©tude concerne, le screening phytochimique et l’évaluation de l’activitĂ© larvicide des extraits (aqueux et mĂ©thanoliques) de 26 plantes sur les larves d’AnophĂšles gambiae s.l. Les tests larvicides ont Ă©tĂ© rĂ©alisĂ©s selon un protocole de l’OMS(1985). Le profil phytochimique des plantes a Ă©tĂ© dĂ©terminĂ© suivant les mĂ©thodes standards de caractĂ©risation (rĂ©actions colorĂ©es). Une forte activitĂ© larvicide vis-Ă -vis des larves d’AnophĂšles gambiae aprĂšs 24h puis 48h d’exposition a Ă©tĂ© observĂ©e. Crotalaria podocarpa, Momordica balsamina, Xeromphis nilotica et Senna occidentalis ont montrĂ© un taux de mortalitĂ© de 100% aprĂšs 24h d’exposition. L’activitĂ© larvicide est beaucoup plus importante aprĂšs 48h. Une mortalitĂ© de 100% a Ă©tĂ© observĂ©e avec Senna occidentalis, Momordica balsamina, Ocimum basilicum, Citrus sinensis, Striga hermontheca, Xeromphis. nilotica, Crotalaria podocarpa, Diospyros mespiliformis, Cymbopogon citratus, Cleome viscosa et Combretum micrantum. De faibles activitĂ©s larvicides ont Ă©tĂ© constatĂ©es d’une part avec les extraits mĂ©thanoliques de Crotalaria podocarpa et Aloe vera et d’autre part avec les extraits aqueux de Citrus sinensis, Ocimum basilicum et Aloe vera. Le screening phytochimique a mis en Ă©vidence la prĂ©sence de cinq (5) grands groupes de composĂ©s parmi lesquels les saponosides, les terpĂšnes stĂ©rols, les flavonoĂŻdes, les tanins et les alcaloĂŻdes aussi bien prĂ©sents dans les extraits aqueux et mĂ©thanoliques des diffĂ©rents Ă©chantillons des plantes. Ces groupes chimiques pourraient justifier l’utilisation traditionnelle de ces plantes

    Approvisionnement En Eau Dans La Ville De Brazzaville, Congo

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    The difficulty of water supply is a major problem faced by the households of Brazzaville in Congo. The objective of this study is to list and identify the different types of water used, and to assess the general hygiene of households. The method used in this prospective study is based on an onsite survey and direct measurement. The survey involves administering a questionnaire to the households in the 9 districts of the city of Brazzaville. 630 households were surveyed. 70 households were drawn in this study and were selected in each borough. There are many sources of water. Overall, 80.16% of households consume water from the SNDE. The survey revealed that 71.00% of households walk on foot to get access to water supply. Plastic cans and buckets are used more in the transportation (43.00 and 37.00 %) and storage (45.00 and 39.00 %) of water. The water storage period is relatively long. It can hold water from 3 days (21.00%) to more than one week (13.00 %) for some households. Analysis of the results of the survey showed that the sources of water supply are diversified. This diversification is due to the phenomenon of shortage and/or repeated water cut recorded by households. Water supply, transport and storage practices, and the cleaning of water containers highlight the precarious conditions of hygiene and sanitation households in the city of Brazzavill
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