ANTISICKLING ACTIVITY EVALUATION OF FRACTIONS OBTAINED FROM WHOLE EXTRACTS OF NEWBOULDIA LAEVIS P. BEAUV (BIGNONIACEAE)

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

Differential constituents in roots, stems and leaves of Newbouldia laevis Thunb. screened by LC/ESI-Q-TOF-MS

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Chemical composition and antioxidant activities of different parts of Ficus sur

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 activit

A significant antihypertensive effect of Holarrhena floribunda supported by an exploratory phytochemical study

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 medicin

AGRONOMIC CHARACTERIZATION OF SIX TOMATO GENOTYPES IN TOGO

The study was carried out to determine the agronomic performance of height tomato genotypes. These genotypes were evaluated in a completely random block design with 4 replications. Analyses of variance and means comparison (P≤5%) revealed that he germination rate of genotypes was greater than 80% except for TLCV 15 (24%). The number of leaf per plant ranged from 11.62 to 15.73. The largest size was obtained by IVF 328 with 66.34 cm in height and the smallest size was obtained by the TLCV 15 with 51.46 cm. The yield results showed that IVF 328 and Mongal F1 were better with 26.28 tons/ha and 26.07 tons/ha respectively. Regarding the number of fruit per plant, IVF 328 and IVF 5248 were more productive. Analysis of variance showed that the fruit weightwas significantly higher for the Mongal F1 and lower for the TLCV 15. The results obtained will help in decision making toward the production of these genotypes in Togo, thereby improving tomato production

A Comparative Study of the Chemical Composition of the Extracts from Leaves, Stem Bark, and Root Bark of Cassia sieberiana: Antibacterial Activities

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

Diastereoselectivite de l'addition de Michael d'enethiolates avec les enones acycliques : regioselectivite de la reaction de nucleophiles ambidents

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Cyclodextrin retinylidene: A biomimetic kinetic trap model for rhodopsin

Abstract-All trans retinal was attached to both the primary face and the secondary face of b-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

PHYTOCHEMICAL STUDY AND ANTIOXIDANT, ANTIBACTERIAL AND ANTIDIABETIC ACTIVITIES OF FLACOURTIA INDICA LEAVES EXTRACTS FROM THE TOGOLESE FLORA

Objective: Faced with the devastating effect of diabetes, the search for new natural antidiabetic molecules is an exploratory avenue. Methods: In this study, the leaves of Flacourtia indica were collected from the Togolese flora, and their antioxidant activity was evaluated using DPPH and FRAP assays, following a phytochemical screening conducted through colorimetric and precipitation reactions. The content of total phenols was determined using Folin-Ciocalteu's reagent and flavonoids by aluminum trichloride. The antibacterial activity of the extracts was evaluated using the method of dilution in agar wells with Muller-Hinton® agar. Additionally, the extracts' antidiabetic effect was evaluated in rats made diabetic by alloxan at a dose of 120 mg/kg. b.w. Results: The results of our work showed the presence of flavonoids, tannins, anthocyanins, and saponins in the extracts. The best polyphenol and flavonoid contents were measured in the hydroethanolic extract and were 186.46±0.308 mg EqAG/g and 464.14±17.043 mgEqQ/g. ES respectively. The hydroethanolic extract has a higher antioxidant power with an IC50 = 110.22 µg/ml. The reducing powers of the ferric ions were 3706±12.124 and 3777±9.238 µmol/ml, respectively for the hydroethanolic and aqueous extracts. The extracts were active against Staphylococcus aureus and are bacteriostatic. The hydroethanolic extract of the leaves of Flacourtia indica significantly reduced (p = 0.0014) blood glucose levels in diabetic rats. Conclusion: This plant can therefore be a potential medicine in the treatment of diabetes