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Introduction: Bridelia ferruginea is a plant known for its antidiabetic properties. However, few studies on leaf extracts have induced anti-hyperglycemic activity on normal mice subjected to carbohydrate overload. The current study was designed to assess the effect of the leaf extracts’ fraction on fructose-induced diabetic mice. Methods: The in vitro ferric-reducing antioxidant power (FRAP) assay were carried out and the condensed tannins quantified. The vanillin-HCl method was used to characterize the condensed tannins. The antidiabetic effect on fructose-induced diabetic mice was evaluated for 28 days using a fructose-enriched fat diet approach. Results: The fraction confirmed the antioxidant activity with a reducing power of 800 μg/mL comparable to ascorbic acid at 200 μg/mL. The condensed tannins were estimated at 79.6 ± 3.4 mg catechin equivalent per gram of sample. Significant decreases in blood sugar levels of 6.25% at the 7th day, 11.04% at the 14th day, 12.61% at the 21th day, and 11.35% at the 28th day were obtained in mice treated with the extract dose of 200 mg/kg of body weight, compared to the positive control group. The decreases of 37.11% of triglycerides and 40.16% of total cholesterol were also obtained. Conclusion: The investigated fraction showed notable antidiabetic activity and might be a good candidate in the treatment of diabetes.

The use of Chenopodium ambrosioides in some communities in Togo reveals its importance and its medicinal properties. The plant is often infused for medicinal drinks before use. Thus, through a comparative study, this work focused on the identification of the different phytochemical groups and then on the anti-radical capacities of ethanolic and aqueous extracts of aerial parts (lea- ves and seeds) of Chenopodium ambrosioides obtained by maceration and infusion. The phytochemical tests, carried out on the various extracts, showed that they contained certain biomolecules such as flavonoids and tannins. Likewise, the presence of terpenoids and terpenes has been detected. However, it is only in aqueous extracts that the alkaloids have been revealed. The determination of the polyphenol content of the extracts revealed that the aqueous infusion contains 25.699 mgGAE/g DE, followed by the aqueous maceration: 24.873 mgGAE/g DE, after the ethanolic infusion: 21.009 mg GAE/g DE and of the ethanolic maceration: 20.625 mg GAE/g DE. The results of the determination of the anti-radical capacity by the DPPH method after calculation of the IC50, revealed that the infusion gives respectively in aqueous and ethanolic medium: 25.541 μg/ml and 48.269 μg/ml while the maceration leads to 29.187 μg/ml 50.999 μg/ml respectively. This study showed that each extract reacted with DPPH and the aqueous infusion was the most reactive.

In Togo, the abusive use of the root of Cassia sieberiana D.C. in traditional medicine, contributes gradually to the rarefaction of the species. The general objective of this study is to promote the use of vital organs of Cassia sieberiana in traditional medicine in Togo. The identification of secondary metabolites of the extracts (cyclohexane, dichloromethane and methanol) was carried out by GC-MS and by CL-MS / MS. The antibiotic susceptibility test was performed according to the well diffusion method and the MICs and MBCs according to the tube dilution method. Compounds such as sitosterol α-acetate, β-sitosterol, emodin, chaetochromine, luteolin, (±) -catechin, naringenin 5-O-rhamnoside, guibourtinidol- (4 alpha-> 6) -catechin and (-) - epiafzelechin are found in the root and in the stem bark. The identified molecules give the different methanolic extracts, an antibacterial effect on all the germs tested. At the end of this study, it appears that the chemical composition of the stem bark is almost similar to that of the root bark. The leaves would be better placed for the treatment of bacteria tested.

Plant parasitic nematodes are among the most destructive plant pathogens worldwide and their control is very challenging. Plant essential oils (EOs) have showed a great potential in nematode control. In this work, EOs from 10 aromatic plants acclimatized in Togo were assessed in vitro for their nematicidal activity on the root-knot nematode Meloidogyne incognita. EOs were subsequently analyzed by GC-MS and compounds were tested individually on nematodes. The most potent EOs were: Ocimum sanctum L., Cymbopogon schoenanthus (L.) Spreng and Cinnamomum zeylanicum Blume with EC50/72h values of 282 ± 53, 288 ± 30 and 355 ± 126mg/L, respectively. The EC50/48h values of tested compounds were 81 ± 14, 117 ± 33, 128 ± 42, 141 ± 47, 168 ± 40, 216 ± 86 and 235 ± 43mg/L for cinnamyl acetate, methyl eugenol, cinnamyl alcohol, acetyl eugenol, isoeugenol, eugenol and benzyl benzoate, respectively. Furthermore, we found a synergistic nematicidal activity when we combined phenylpropanoids compounds with carvone. EOs and their constituents described herein merit further studies, especially in pot experiments before serving as nematicides.

Newbouldia laevis (P. Beauv.) Seem. or “Boundary Tree” is a medium sized angiosperm in the Bignoniaceae family. It is native to tropical Africa, especially used in West Africa to mark property boundaries in rural areas. Despite its intensive use in folk medicine, the plant chemical composition is under investigated. The study is aimed at identifying the chemical constituents of N. laevis crude plant extracts by high-performance liquid chromatography (HPLC) on line with an untargeted high-resolution mass spectrometry. The used HPLC method showed to be suitable for the determination of withasomnine, newbouldine, and lapachol derivatives together with other known bioactive compounds like phytosterols and triterpenoids. The importance of these chemical constituents is discussed with respect to the role of N. laevis in West African ethnomedicine.

Objective: This study aims to evaluate the fractions from whole extracts of roots and stem barks of Newbouldia laevis and their effect on sickling. Methods: Hydroethanolic extracts of stem barks and roots of Newbouldia laevis were fractionated by the technics of cold precipitation in ethanol. The fractions obtained after phytochemical screening were subjected to Emmel test to evaluate their anti-sickling activity. Active fractions were tested for DPPH and AAPH assay (AAPH induced membrane lipoperoxidation and evaluation of reduction of hemolysis). Results: Two fractions were obtained from each whole extract: supernatant and pellet fractions. Supernatants fractions obtained from whole roots barks extract and stem barks extract at a concentration of 30 mg/ml reduced sickling up respectively to 7% and 10% against 86% for the control. Pellets fractions obtained from the both extracts induced coagulation of SS blood at 30 mg/ml against 86% for the control. Conclusion: Supernatants fractions of hydroethanolic whole extract of roots and stem backs of Newbouldia laevis promise as the potential source of active molecules against sickle cell disease.

Introduction: Ficus sur is a plant widely used in traditional pharmacopoeia in Togo. So, this study aimed the assessment of antioxidant properties and identification of some compounds from the ethanolic extracts of different parts of the plant (leaves, fruits, roots, and barks). Methods: The phenolic and flavonoid contents of the ethanolic extracts of different organs of Ficus sur were assessed using conventional known methods. The DPPH radical scavenging and the ferric-reducing antioxidant power (FRAP) assays were used to highlight the antioxidant activities. The different extract samples were also analysed by liquid chromatography coupled to a quadrupole-time of flight mass detector (ESI-QTOF). Results: Total phenolic contents (TPCs) for 1 mg of dry extract ranged from 489.40 ± 7.48 μg GAE (gallic acid equivalents) for the bark to 62.34 ± 2.66 μg GAE for unripe fruits. The bark exhibited the highest flavonoid content, which was closed to 90.20 ± 3.72 μg QE (quercetin equivalents)/mg of dry extract. The radical scavenging activities of the bark and unripe fruits were 56.50 ± 0.29 and 7.3 ± 0.30 μg QE/mg of dry extract, respectively. In the same order, the FRAP values of the two organs were 104.57 ± 4.75 and 19.61 ± 0.22 μmol FeSO4 Eq/mg of dry extract. Many compounds including notoginsenoside R10; 4’,5,7-trihydroxyflavan-3-ol; catechin; and boviquinone 4 were identified. Conclusion: The various organs of Ficus sur are a source of bioactive compounds especially phenolic compounds and flavonoids with antioxidant activity.

Introduction: Holarrhena floribunda (G.Don) T.Durand & Schinz is a tree that can grow up to 25 m with white latex in its organs. The bark of this plant is commonly used in traditional medicine to treat dysentery, diarrhea, diabetes, malaria, and high blood pressure. In this study, phytochemical groups were widely investigated on trunk bark as well as on leaves of H. floribunda harvested in Danyi (Togo). Antioxidant activity and antihypertensive properties of the plant extracts were also evaluated on sound guinea pigs. Methods: The hydro-ethanolic extract of the trunk bark was prepared and antioxidant activity was evaluated via the DPPH radical-scavenging and the ferric-reducing antioxidant power (FRAP) methods, and via the determination of the total phenolics content. This hydro-ethanolic extract was used to assess the plant extract effect on blood pressure of sound guinea pigs. Results: So, phytochemical screening revealed that H. floribunda contained most of the phytochemical groups. The 50% inhibitive concentration of that extract by DPPH was 29.80 ± 0.001 μg/mL. The equivalent of Fe2+ by FRAP was 1009.9 ± 0.6 μmol/g of dry extract. The content of phenolic compounds was 139 ± 0.053 mg GAE (gallic acid equivalents)/g of dry extract. Intravenous injection of the extract (10, 20, 40, 80 mg/kg) via the invasive method in guinea pigs under normal strain caused a decrease in diastolic blood pressure, systolic blood pressure, and so in mean arterial pressure (MAP) by dose cumulative and time-dependent. Conclusion: The results show that hydro-ethanolic extract of H. floribunda trunk bark has antihypertensive and antioxidant properties. This might be the reason for the use of that extract for the treatment of hypertension in traditional medicine

Four cyanostyryl-substituted carbazole derivatives (CN-ODEC1, CN-ODEC2, CN-DDEC1, and CN-DDEC) were synthesized and their self-assembly properties have been studied. It was found that they could form organogels especially in aromatic solvents. Scanning electron microscopy and light microscopy images show that the xerogels formed from monosubstituted derivatives (CN-O/DDEC1) gave well-organized tapes, and those from disubstituted derivatives (CN-O/DDEC2) exhibited heavy entangled three-dimensional structures. The UV–vis absorption and fluorescence emission spectra, as well as X-ray diffraction patterns, suggest that carbazole derivatives underwent J-type π-stacking. Meanwhile, we suggested that strong H-bonding and moderate π–π interactions were the key driving force for the gelation of the monosubstituted derivatives, and head-to-tail “ladder-type” J-aggregates were formed in the gel state. On the other hand, strong π–π interaction might be considered as the main driving force for the gelation of disubstituted derivatives, and J-aggregates with no well-organized packing mode of molecules were obtained in the gel phase. It should be noticed that aggregation-induced emission was observed during the gelation processes.

Sickle cell disease is a genetic disease very expanded all over the African block. In Togo like most African countries, it’s one of major causes of morbidity and mortality. The available treatments are very ornamental and are most of the time remedy than cure. However, in our areas, the sicks use medicinal plants for treating themselves. It’s in this scope that this study has been conducted in sight of assessing the anti-sickling activity of Newbouldia laevis extracts (leaves, roots and stem barks) based on Emmel test using 2% sodium metabisulphite. The extracts were also studied for its in vitro antioxidant activity using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2’-azobis (2-amidinopropane hydrochloride) (AAPH) methods. The results obtained show that the roots and the stem barks extracts have a comparable efficiency. These extracts enabled us to reduce the sickling rate respectively at 17% and 16% against 78% for the control that was incubated in the presence of 0.9% sodium chloride. The leaves extract led to hemolysis and hemolysing concentration was 5mg/ml. Light antioxidant activity in vitro was obtained for the two extracts. Our outcomes proved that in vitro , roots and stem barks of Newbouldia laevis extracts have an anti-sickling activity contrary to the hemolysing leaves extract. © 2018 International Formulae Group. All rights reserved. Keywords: Sickle cell disease, sickling, Newbouldia laevis , Metabisulphite

The root bark of Cassia sieberiana was analyzed using direct analysis in real time mass spectrometry, and a main flavonoid component with an [M + H](+) mass of 275 was identified. The flavonoid, epiafzelechin, was isolated and fully characterized with the concerted use of NMR spectroscopy, circular dichroism, and optical rotation. Electronic circular dichroism and optical rotation TDDFT calculations were also performed, and their agreement with the experimental results confirmed the enantiomeric identity of the isolated natural product. The antioxidant activity of the compound was also investigated.

Dans cet article, les 3 organes de C. sieberiana recoltee au Togo ont fait l’objet d’une etude comparative pour la determination de leur composition phytochimique, teneur en phenols et flavonoides totaux, et activites antioxydantes. Le tri phytochimique a ete realise grâce aux reactions de colorimetrie et precipitation. La teneur en phenols totaux a ete determinee grâce au reactif du Folin-Ciocalteu et celle des flavonoides par AlCl 3 . L’activite antioxydante a ete evaluee par les methodes de DPPH et FRAP. Les resultats obtenus ont montre que les 3 organes de la plante contiennent des grands groupes chimiques, tels que les flavonoides, tanins et saponosides. Les teneurs en phenols totaux des extraits ethanoliques sont (en mg EAG/g) de 276,62 ± 26,120 (feuilles) ; 345,04 ± 3,160 (ecorces) ; 327,16 ± 3,990 (racines). Celles des flavonoides totaux sont (en mg EQ/g) de 34,134 ± 4,324 (feuilles) ; 36,430 ± 2,022 (ecorces) et 37,270 ± 2,216 (racines). Les extraits ethanoliques des 3 organes ont un pouvoir antioxydant appreciable. En conclusion, les resultats obtenus revelent que les racines et ecorces ont des activites antioxydantes semblables, toutefois ne permettent pas a ce stade de la recherche de preciser l’organe approprie pouvant remplacer les racines. © 2017 International Formulae Group. All rights reserved. Mots cles: Cassia sieberiana ; composition phytochimique activite antioxydante ; phenols totaux English Title: Comparative antioxidant potential study of different part of Cassia sieberiana English Abstract In 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 AlCl 3 . 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 phenols

Ficus sur est une plante alimentaire couramment utilisee en medecine traditionnelle au Togo. Elle a cependant fait l’objet de tres peu d’etudes phytochimiques. Le present travail a pour but de valoriser cette espece a travers l’identification continue de ses metabolites. Ainsi, l’extraction cyclohexanique au Soxhlet a ete realisee sur les feuilles de Ficus sur . Cet extrait cyclohexanique obtenu a ete ensuite fractionne puis purifie par chromatographie sur colonne de gel de silice. L’identification des composes a ete realisee par GC-MS, precedee quelquefois d’une etape de derivatisation. Treize fractions (A1 a A13) ont ete obtenues du fractionnement de cet extrait. Apres deux purifications successives de la fraction A5, deux sous-fractions A5.1 et A5.2 ont ete obtenues. Le spectre de masse d’un compose de A2 presente un pic moleculaire a m/z 426 et des pics fragments [M-69] + , [M-154] + , [M-169] + , [M-197] + , [M-208] + et [M-219] + caracteristique du taraxasterol. Pour A5.2 derivatisee, un compose presente un spectre de masse de pic moleculaire a m/z 486 et des pics fragments [M-90] + , [M-129] + et [M-357] + propres au β -sitosterol trimethylsilyl ether derive du β - sitosterol. La presence de ces deux phytosterols bioactifs serait un atout majeur dans l’usage therapeutique de cette plante. © 2017 International Formulae Group. All rights reserved. Mots cles: Ficus sur , GC-MS, taraxasterol, β -sitosterol English Title: Identification of two bioactive phytosterols of the cyclohexane extract of Ficus sur (moraceae) leaves English Abstract Ficus sur is a food plant commonly used in traditional medicine in Togo. However, few phytochemical studies of this species are available. This work aims at contributing to the enhancement of this approach through an identification of its metabolites. The leaves of Ficus sur were then extracted with cyclohexane using soxhlet. The obtained cyclohexane extract was fractionated and purified by chromatography on silica gel column. Identification of the compounds was carried out by GC-MS, sometimes preceded by a derivatization step. Thirteen fractions (A1 to A13) were obtained from the fractionation of this extract. After two successive purifications of the fraction A5, two subfractions A5.1 and A5.2 were obtained. The mass spectrum of a compound of A2 has a molecular peak at m/z 426 and peaks [M-69] + , [M-154] + , [M-169] + , [M-197] + , [M-208] + and [M-219] + characteristic of taraxasterol. For the derivatized fraction A5.2, a compound has a mass spectrum of molecular peak at m/z 486 and peaks [M-90] ++ and [M-357] + characteristic of β -sitosterol trimethylsilyl ether derived from β -sitosterol. The presence of these two bioactive phytosterols would be a major asset in the therapeutic use of this plant. © 2017 International Formulae Group. All rights reserved. Keywords: Ficus sur , GC-MS, taraxasterol, β- sitosterol

De nos jours, la filière karité a une importance socio-économique non négligeable dans le développement des grands producteurs mondiaux de beurre de karité. Le présent travail a pour objectif de faire une enquête sur les profils des unités de production, les procédés de collecte des amandes et de production de beurre, les rendements d’extraction de beurre et les caractéristiques sensorielles des beurres de karité afin de faire l’état des lieux de la filière karité au Togo. Les résultats obtenus ont montré que 31,25% des unités de production avaient recours au barattage classique, ensuite viennent les procédés de barattage Peuhl (25,00%) et de cuisson directe (25,00%). Les techniques industrielles (UIP1 et UIP2 : 06,25% chacune) ainsi que le barattage sans torréfaction (06,25%) sont les moins pratiqués. Les rendements en beurre sont de : 49,00% (UIP1) ; 48,63% (barattage Peuhl) ; 43,25% (barattage classique) ; 42,00% (UIP2), 31,33% (barattage sans torréfaction) et 27, 91% (cuisson directe). S’agissant des caractéristiques sensorielles, trois types de couleur ont été identifiés, avec une prédominance des beurres à couleur beige (60,00%), tandis que les proportions des couleurs jaune et gris sont de 20% chacune. Cependant, la texture compacte a occupé une proportion de 93,00%. Fort de ces constats, il est alors envisagé par la suite des études supplémentaires sur des paramètres physico-chimiques des échantillons afin de mieux apprécier la qualité des beurres de karité produits au Togo.Mot clés : Beurre, unités de production, procédés d’extraction, rendements en beurre, caractéristiques sensoriellesEnglish Title: Assessment of shea butter production techniques in TogoEnglish AbstractNowadays, the shea sector has a significant socio-economic importance in the development of the world largest producers of shea butter. The objective of this study is to investigate the profiles of production units, almonds collection processes and production of butter, butter extraction yields and sensory characteristics of shea butters produced to make a critical review of the different processing methods in Togo. The results obtained showed that 31.25% of production units were using the classic churning, followed by Fulani churning processes (25.00%) and direct cooking (25.00%). Industrial technology (UIP1 and UIP2: 06.25%) and churning without roasting (06.25%) are the least practices. Butter yields found are: 49.00% (UIP1); 48.63%) (Fulani churning); 43.25% (classical churning); 42.00% (UIP2), 31.33% (churning without roasting) and 27, 91% (direct cooking). Regarding the sensory characteristics, three kinds of colour have been identified, with a predominance of beige butters (60.00%, while the proportions of yellow and gray colours are 20% each one. However, the compact texture has held a proportion of 93.00%. In the light of the forgoing a comprehensive study of physical and chemical parameters of the butters should be undertaken in order to better assess the quality of shea butter produced in Togo.© 2017 International Formulae Group. All rights reserved.Keywords: Butter production units, methods of extraction, butter yields, sensory characteristics

Reacion of titanium enethiolates with α-unsaturated ketones leads selectively to 3-hydroxy 4-saturated alkanedithioates, arising from a 1,2-carbon-addition, whereas aluminum enethiolates give oxoketene dithioacetals, from exclusove 1,4-sulphur-addition.

Mass spectrometry was performed on self-assembled monolayers (SAMs) of dodecanethiol on gold using the new direct analysis in real time (DART) ionization technique. Observed peaks for the SAMs included monomers, dimers, and trimers of the SAM molecules, with the dimer and trimer relative peak heights enhanced as compared to the spectra for neat dodecanethiol. The possibility that the observed peaks were due to residual (noncovalently bonded) material on the surface was tested by attempting to observe residual dodecanol. No peaks corresponding to dodecanol were observed. These results indicate that DART is an excellent ionization method for the direct and unambiguous mass analysis of chemical species in self-assembled monolayers.

All trans retinal was attached to both the primary face and the secondary face of β-cyclodextrin via a Schiff base linkage, analogous to that in rhodopsin. The new models were evaluated and compared with n -butylamine retinylidene Schiff base for their rates of hydrolysis, and factors that influence such rates. Competition studies using adamantane carboxylate demonstrated the kinetic trap theory by diminishing the binding of retinal in the cyclodextrin, thereby augmenting the rate of hydrolysis. NMR experiments indicate that the retinylidene is most probably bound in the form of a dimer.

1,4-Addition reaction of lithiated dithioesters with acyclic β-substituted E enones affords diastereomeric 5-oxo-alkanedithioates. Anti configuration was assigned to the major diastereoisomer by chemical correlation. This stereochemistry depends on the configuration of the prochiral partners. The cisl/trans ratio of intermediate enethiolates was analyzed by trapping experiments. Two cases of highly selective cis deprotonation of dithioesters were observed. Michael addition with E-enones (3-penten-2-one, chalcone) occurs with high stereospecificity: anti/syn product ratios are identical to the cis/trans enethiolate ratios. A pseudo-cyclic transition state is proposed with substituents of the enone C-C double bond occupying favorable equatorial positions. The 1,4-addition reaction is kineticaly controlled. In contrast to ester enolates, enethiolates allow the use of enones without the need of tertiobutyl or phenyl groups. The observed diastereoselectivity (ratio anti/syn up to 95 : 5) offers a new means of creation of two vicinal carbon substituted asymmetric centers by carbon-carbon bond formation in the acyclic series. Poor selectivities were however observed when using unsaturated diesters as acceptors.

Cis lithium enethiolates, generated from substituted dithioesters, undergo 1,4-addition uith vapious β-monosubstituted α-unsaturated ketones. With acyclic enones one of the tw resulting diastereomeric 5-oxodithioesters is predominantly formed (ratio up to 95 : 5). Its anti configuration was proven by chemical correlation in one case. Evidence for fhe stereospecificity of this Michael, addition is given.