35 research outputs found
Chemical Composition of Different Extracts of Conyza bonariensis: Insecticidal and Nematicidal Activities
No full textC. bonariensis (L.) Cronq. known as hairy fleabane was first described in Argentina but it is now widely spread through most warmer regions of Europe,
Africa, Asia, the Caribbean and Central America. In this work, a chemical
analysis by liquid and gas chromatography coupled with mass spectrometry
of the whole plant, aerial part, flowers and roots extracts of C. bonariensis
harvested in Togo (West Africa) was carried out. Two acetylenic compounds
Lachnophyllum ester and limonene were identified as the main components
of essential oils while Lachnophyllum and Matricaria lactones were dominant
in chloroform extracts. Based on the plant chemical compositions, essential
oils and chloroform extracts were tested on cowpea weevil Callosobruchus
maculatus adults which are considered as one of the most cosmopolitan pests
of stored beans, and on freshly hatched second-stage juveniles of root-knot
nematode Meloidogyne incognita. Results showed that the whole plant essential oil demonstrated an LC50/24h value of 1.75 μL oil/L air on C. maculatus
while at 3.91 μL oil/L air, it showed 100% mortality. Furthermore, the plant
root chloroform extracts partitioned in diethyl ether-hexane mixture showed
the strongest nematicidal activity with an LC50/72h value of 0.47 mg/mL. Our
findings suggest that the widely diffused plant C. bonariensis and its acetylenic constituents could be considered as potent botanical insecticidal and
nematicidal agents
Determination of tetrahydrocannabinol and cannabidiol contents in Cannabis sativa L. samples in Togo using gas chromatography-mass spectrometry
No full textCannabis sativa L. is a widely used recreational drug in Togo, especially among young people. However, little is known about its chemical composition in Sub-Saharan Africa, and specifically in Togo. This study aimed to determine the levels of phytocannabinoids, specifically Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD), in cannabis samples collected from various towns in Togo using gas chromatography coupled to mass spectrometry (GC-MS). Thirteen cannabis samples were extracted with hexane using maceration and ultrasound to isolate phytocannabinoids, and a quick 24-min gas chromatographic separation method was used to analyse the extracts. THC, CBD, and cannabinol (CBN) were the major components identified in the samples. THC content ranged from 37.73±0.31 to 87.9±1.30% for maceration and from 39.09±2.17 to 84.54±0.80% for sonication, while CBD content varied from 1.36±0.27 to 4.07±0.23% for maceration and from 1.79±0.12 to 5.03±0.90% for sonication. These results indicate that cannabis consumed in Togo has high concentrations of THC and that maceration and sonication is more likely to extract THC and CBD, respectively. The findings could provide important information for the authorities in Togo to assess the extent of THC exposure among cannabis consumers in the country
Extractions, analyses chromatrographiques et activités antibactériennes de Grewia cissoides et Grewia lasio-discus
No full textInternational audienc
Extractions, analyses chromatrographiques et activités antibactériennes de Grewia cissoides et Grewia lasio-discus
No full textInternational audienc
Extractions, analyses chromatrographiques et activités antibactériennes de Grewia cissoides et Grewia lasio-discus
No full textInternational audienc
Impact du compostage sur la réhabilitation de la carrière de calcaire de Sika-Kondji (Togo) : effets sur l’attraction des animaux et sur la performance du maïs (Zea mays L.)
No full textL’exploitation minière contribue à la destruction du sol et de la biodiversité augmentant la pauvreté surtout dans les pays en voie de développement. La restauration d’une mine constitue une obligation pour un développement durable. Dans cette étude des déchets d’un site minier ont été valorisés pour attirer et maintenir certains animaux sur le site et fertiliser le topsol. Il ressort que les insectes sont plus liés aux composts C1 (déchets verts) et C2 (déchets verts et alimentaires) tandis que les composts C3 (déchets verts + calcaires et l’argile) et C4 (déchets verts + alimentaires + calcaires et argiles) attirent plus les amphibiens et les arachnides. Le tas du compost C2 est le plus visité par ces animaux (43 % par rapport aux individus totaux). L’analyse chimique des composts a montré que les composts C2 et C4 présentent les fortes teneurs en matière organique et en azote (1,20 et 0,75 % m.s.), en phosphore (0,45 et 0,38 % m.s.) tandis que les composts C1 et C2 présentent les plus fortes teneurs en potassium (0,48 et 0,60 % m.s.). En ce qui concerne les effets des composts sur la croissance et les paramètres agronomiques du maïs, les plantes cultivées sur les composts C1, C2 et C3 sont celles qui présentent les plus fortes performances. Les composts C1, C2 et C4 seront utilisés dans la restauration de la fertilité du topsol et de la biodiversité de la carrière de Sika-Kondji.Mining activities contribute to soil and biodiversity destruction and Increase poverty especially in developing countries. Restoring a mine in all its aspects after exploitation is a requirement method for sustainable development. The main objective of this study is to restore the fertility of a quarry soil and animals diversity using free wastes. Results indicated that three classes of animals have visited composts piles. They are amphibians, arachnids and insects. Insects are more related to composts C1 (green wastes) and C2 (green wastes + food wastes) while C3 (green wastes + limestone and clay) and C4 (green wastes + food wastes + limestone and clay) attract more amphibians and arachnids. C2 compost pile was most visited by animals (43 % relative to the total individuals). Chemical analysis showed that composts C2 and C4 present the high levels of organic matter, nitrogen (1.20 % and 0.75 ms) and phosphorus (0.45 % and 0.38 ms) contents while composts C1 and C2 have the highest levels of potassium (0.48 % and 0.60 m.s.). Concerning composts effects on agronomics parameters of maize, plants cultivated on composts C1, C2 and C3 are the best. Composts C1, C2 and C4 will be used in restoration programs of Sika-kondji mining site
Etude comparative des activités antioxydantes d’extraits éthanoliques de feuilles, d’écorces et de racines de <i>Cassia sieberiana</i>
No full textDans cet article, les 3 organes de C. sieberiana récoltée au Togo ont fait l’objet d’une étude comparative pour la détermination de leur composition phytochimique, teneur en phénols et flavonoïdes totaux, et activités antioxydantes. Le tri phytochimique a été réalisé grâce aux réactions de colorimétrie et précipitation. La teneur en phénols totaux a été déterminée grâce au réactif du Folin-Ciocalteu et celle des flavonoïdes par AlCl3. L’activité antioxydante a été évaluée par les méthodes de DPPH et FRAP. Les résultats obtenus ont montré que les 3 organes de la plante contiennent des grands groupes chimiques, tels que les flavonoïdes, tanins et saponosides. Les teneurs en phénols totaux des extraits éthanoliques sont (en mg EAG/g) de 276,62 ± 26,120 (feuilles) ; 345,04 ± 3,160 (écorces) ; 327,16 ± 3,990 (racines). Celles des flavonoïdes totaux sont (en mg EQ/g) de 34,134 ± 4,324 (feuilles) ; 36,430 ± 2,022 (écorces) et 37,270 ± 2,216 (racines). Les extraits éthanoliques des 3 organes ont un pouvoir antioxydant appréciable. En conclusion, les résultats obtenus révèlent que les racines et écorces ont des activités antioxydantes semblables, toutefois ne permettent pas à ce stade de la recherche de préciser l’organe approprié pouvant remplacer les racines.© 2017 International Formulae Group. All rights reserved.Mots clés: Cassia sieberiana; composition phytochimique activité antioxydante ; phénols totauxEnglish Title: Comparative antioxidant potential study of different part of Cassia sieberianaEnglish AbstractIn this article, the 3 organs of C. sieberiana harvested in Togo were the subject of a comparative study for the determination of their phytochemical composition, content of total phenols and flavonoids, and antioxidant activities. Phytochemical composition was carried out by colorimetric and precipitation reactions. The total phenol content was determined by Folin-Ciocalteu reagent and total flavonoids by AlCl3. Antioxidant activity was evaluated by DPPH and FRAP methods. The results obtained showed that the 3 organs of the plant contain large chemical groups, such as flavonoids, tannins and saponosides. The total phenol contents of the ethanolic extracts are (in mg EAG / g) of 276.62 ± 26.120 (leaves); 345.04 ± 3.160 (barks); 327.16 ± 3.990 (roots). Those of the total flavonoids are (in mg Eq / g) 34,134 ± 4,324 (leaves); 36,430 ± 2,022 (barks) and 37,270 ± 2,216 (roots). The ethanolic extracts of the 3 organs have an appreciable antioxidant power. In conclusion, the results obtained reveal that the roots and barks have similar antioxidant activities, however do not allow at this stage of research to specify the appropriate organ that can replace the roots.© 2017 International Formulae Group. All rights reserved.Keywords: Cassia sieberiana; phytochemical composition; antioxidant activity; total phenol
Etude chimique sur l’isolement et la synthèse des composés acétyléniques de la plante Conyza bonariensis acclimatée au Togo
No full textInternational audienc
Toward chromatographic bio-guided fractionation of Grewia lasiodiscus extracts active against Staphylo-coccus aureus
No full textInternational audienc
