Anthelmintic and Antioxidant Activities, Phytochemical Profile and Microscopic Features of Senna alata Collected in the Democratic Republic of Congo

Aim: The objective of this study was to determine the phytochemical profile of Senna alata LINN using chemical screening in solution and thin-layer chromatography, and to assess the antioxidant and anthelmintic activities of the plant抯 aqueous extracts. Methodology: All the analyses performed in this study were, respectively, done as described by the standard protocols. These were: the microscopic examination of the plant powders performed using a light microscope, the search for secondary metabolites carried out by chemical screening in solution and by thin-layer chromatography, the determination of the secondary metabolites, and the antioxidant activity carried out by UV-visible spectroscopy and the anthelmintic activity performed by dilution in decreasing order of concentration. Results: Micrographic analysis of the powder of Senna alata revealed the histological elements rich in unicellular covering hairs with a punctate surface and in fragments of palisade parenchyma, with elongated cells. The presence of polyphenols (flavonoids, anthocyanins, tannins, leuco anthocyanins, free quinones), steroids, terpenoids, and iridoids was detected by phytochemical screening in solution and confirmed by thin-layer chromatography. The determination of total phenolic compounds, flavonoids, total tannins, and anthocyanins showed that Senna alata contains 254.64 mg EQ/g, 12.3%, 9.5%, and 6.5%, respectively, of these metabolites. The aqueous extract of the leaves of Senna alata showed a good anthelmintic activity after 41 minutes of exposure to 5.00 mg/mL of the extract and the antioxidant activity was reported, of which the value of IC50 ( g/mL) of the extract for the DPPH tests is 91.42 15.56. Conclusion: Histological elements rich in unicellular covering hairs with a punctate surface and in fragments of palisade parenchyma, with elongated cells were revealed in the micrographic analysis of Senna alata. The plant抯 leaf methanol extract showed good antioxidant activity, while the anthelmintic activity was demonstrated in its aqueous extract.

In vitro Antisickling and Radical Scavenging Activities of a Poly-herbal Formula (Drepanoalpha®) in Sickle Cell Erythrocyteand Acute Toxicity Study in Wistar Albino Rats.

Aims: To evaluate the antisickling and radical scavenging activities and acute toxicity of indigenous nutritive formula Drepanoalpha®, produced through a bio-guided based plant selection. Study Design: Drepanoalpha® extracts, Antisickling activity by Emmel test, Antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl bleaching methods; acute toxicity on rats, determination of biological and haematological parameters. Place and Duration of Study: Science Faculty University of Kinshasa, between January 2013 and February 2014. Methodology: The antisickling and antioxidant activities of Drepanoalpha® were determined using Emmel and the 1,1-diphenyl-2-picrylhydrazyl bleaching methods respectively. Acute oral toxicity test was performed to determine the LD50. Liver and kidney functions, the hematological and histopathological examinations were assessed using standard techniques. Results: Obtained results revealed that Drepanoalpha® possessesinteresting in vitro antisickling and antioxidant activities as revealed by the observed normal biconcave form of sickle erythrocyte (normalization rate >80%) and the radical scavenging activity (ED50= 0.604 ± 0.028 μg/mL). Acute toxicity assessment revealed that the medium lethal dose (LD50) is higher than 4000 mg/kg. Drepanoalpha® significantly increases the values of WBC, RBC, Hb, HCT, PLT, IDR-CV and PCT. Furthermore, this polyherbal formula significantly decreases the values of IDR-SD, P-RGC, AST and ALT (p<0.05). Both the control and treated groups displayed comparable non altered histological architecture of the liver cells. Discussion: The mean values of biochemical markers and hematological markers of treated rats revealed that Drépanoalpha® is potentially safe indicating non-toxic effect of the phytomedicine on immune cells and blood clotting factors. Moreover, this poly-herbal formulation increases the hemoglobin rate in the all treated rats (500-4000 mg/kg bodyweight) and preserves the histological architecture of the liver cells. Conclusion: Drepanoalpha® may increase weight gain, promote erythropoiesis and thrombopoeisis in sicklers patients. This phytomedicine could be used in the treatment of all form of anemia and may also prevent bile duct obstruction or intra-hepatic cholestasis. The results can form the basis for clinical trials in humans.

Antisickling Activity and Membrane Stabilizing Effect of Anthocyanins Extracts from Adansonia digitata L. Barks on Sickle Blood Cells.

Background: Parts of baobab tree (Adansonia digitata) including especially the barks are commonly used for their medicinal properties. Aims: The aim of this work is to evaluate the antisickling activity of baobab tree barks, which are used in Congolese traditional medicine to manage Sickle Cell Disease. Study Design: Baobab tree barks was extracted with water by maceration. Phytochemical tests were conducted with standard procedures. Antisickling activity and the minimum concentration of extract required to normalize sickled cells was determined by Emmel test. Place and Duration of Study: This work was done at department of chemistry, Science Faculty, University of Kinshasa (DR Congo), between November 2012 and February 2013. Methodology: The barks collected from Adansonia digitata were dried and powdered. A chemical screening was perform and extraction of anthocyanins done. Antisickling activity was evaluated by Emmel test, membrane stability by osmotic fragility test and Fe3+ evolution by following solution absorbance at 630nm. The rate of sickle cell shape normalization was determined at different plant aqueous extract concentrations in order to determine the minimal concentration of extract required to normalize sickle cells. The shape modification was quantitatively evaluated from the values of parameters such as surface, radius and perimeters of sickle blood cells before or after treatment with plant extract using Motic software. Results: The aqueous extract of Adansonia digitata showed an antisickling activity with a maximal normalization rate of 65.7% and a minimal concentration required to normalize sickled cells of 5.0mg/mL. The cell surface, perimeter and radius were significantly different before and after treatment with plant extract. The chemical screening showed the presence of polyphenols among which anthocyanins. The biological activity of this plant would be due to these pigments. The anthocyanins extract have also shown a stabilization effect on sickle blood red cells membranes and a reduction of methemoglobin to hemoglobin effect Conclusion: The results obtained show significant antisickling activity of Adansonia digitata barks thus justifying the use of this plant by traditional healers in Congolese traditional medicine in the management of Sickle Cell Disease.

Ethnopharmacological Survey of Medicinal Plants Used against Malaria in Bukavu City (D.R. Congo).

Aims: An Ethnopharmacological survey was conducted in the city of Bukavu, in order to identify plant species and recipes used in Congolese folk medicine for the treatment of malaria. Study Design: Survey; plant collection; plant identification and classification: family, used part, treated disease, recipes preparation; floristic characterization. Place and Duration of Study: “Université Officielle de Bukavu” (DR Congo), from February 2011toDecember 2012. Methodology: Forty-nine healers belonging to different ethnic groups were interviewed about the plant species used in traditional medicine for the management of malaria in the city of Bukavu. The name of the plants, the plant parts, the modes of preparation and the modes of administration of recipes were recorded. Cited plants were collected and identified at herbarium of the Laboratory of Ecology and Plants Resource Management, Faculty of Sciences, “Université Officielle de Bukavu”. The plants ecological status was also determined. Results: Forty species of plants belonging to twenty seven botanical families were identified. The main habitat preference of species is cultivated (62%), trees constituted 33% of morphological type while 30% of biological type are microphanerophytes. The decoction was the main mode of preparation (47.5%) and almost all recipes (100%of cases) are administrated by oral route. Leaves constituted sixty percent of plant organs used for drug preparation. Conclusion: Some plant species cited (62.5%) are known in the literature to possess antimalarial activity. Further studies should be undertaken to investigate effectiveness of other plants that have not yet been studied and to determine their chemical composition.

Anti-Hyperglycemic Activity of Raphia gentiliana De Wild. (Arecaceae).

Aims: Raphia gentiliana De Wild fruit is edible. The aim of this work is to evaluate the anti-hyperglycemic activity of this fruit for its use as medicinal food. Study Design: Phytochemical analysis; extraction by lyophilzation process; measure of blood glucose level; calculation of glycemic load and index. Place and Duration of Study: National Institute of Biomedical research (DR Congo), between October 2011 and June 2012. Methodology: The study was performed in vivo (mice and humans). A Dose of 0.2g/Kg of Raphia gentiliana fruit extracts was administered to fasting (18 hours) hyperglycemic induced NMRI mice by oral application. The kinetics profile of the blood sugar level of the hyperglycemic induced mice was evaluated using a glucometer after one to two hours of administration. For humans, the Raphia gentiliana fruit was taken by 45 consenting individuals. Glycemia was measured by spectrophometry and the triangle surface area ratio’s method was used to calculate the glycemic and load index. Results: The results about the anti-hyperglycemic activity in NMRI’s mice showed a significant decrease in blood sugar level. After oral application of aqueous Raphia gentiliana fruit extracts, the decrease of 27% and 56% were observed after respectively one and two hours. For human subjects, observed values of glycemic index and load were -3.1% and -1.36% respectively. These negative glycemic index and glycemic load values are excepted standard. Conclusion: The obtained results indicate that Raphia gentiliana fruits have an antihyperglycemic activity and justify the use of this plant in Congolese traditional medicine.

Etude par spectroscopie UV-visible de la denaturation thermique de l'hemoglobine S : une nouvelle approche du depistage rapide de la drepanocytose

La denaturation thermique des hemoglobines A et S dans le sang total a ete etudiee par spectrophotometrie UV-visible. Les resultats (exprimes en terme de temperature detransition =Tt) indiquent qu'a pH 7.4 et sans ajout d'electrolyte; la denaturation thermique montre la meilleure discrimination des sangs AA; AS et SS. Les valeurs calculees de Tt; sur base de l'analyse par regression non lineaire d'une fonction sigmoidale; a l'aide du programme Origin 4;0 sont 65;2 ; 61;0 et 58;0 oC respectivement pour les sangs AA; AS et SS. Ces resultats; obtenus dans un milieu ne necessitant pas la purification prealable des hemoproteines; montrent que la temperature de transition offre; comme la mobilite electrophoretique; la possibilite de depister la drepanocytose. L'essai d'utilisation de la denaturation thermique comme technique de caracterisation des hemoglobines a montre la pertinence de la methode

Activite antifalcemiante et thermodegradation d'une fraction d'anthocyanes extraits de Zizyphus mucronata

L'activite antifalcemiante de Zizyphus mucronata; une plante utilisee en medecine traditionnelle congolaise pour la prise en charge de l'anemie SS; a ete evaluee en utilisant le test d'Emmel. Les anthocyanes extraits des feuilles de Zizyphus mucronata; ont montre in vitro une bonne activite antifalcemiante. La concentration minimale de normalisation a ete determinee; et la chromatographie sur couche mince utilisant le melange dichloromethane-benzene comme solvant d'elution dans le rapport 6 :4 a indique la presence de deux spots differents avec comme valeurs des rapports frontaux (Rf) 0;24 et 0;31 (fraction 1 et fraction 2 respectivement). La premiere fraction (Rf : 0;24) d'anthocyanes isolee a montre une grande activite. L'etude de l'effet de la chaleur sur la fraction 1 a indique l'instabilite des anthocyanes extraits de Zizyphus mucronata vis-a-vis de la chaleur. Conclusion : L'activite antifalcemiante de Zizyphus mucronata a ete confirmee in vitro. Cette activite serait due aux anthocyanes dont la fraction 1 isolee est la plus active. Cette fraction est instable vis-a-vis de la chaleur. Il serait donc mieux d'eviter de soumettre la plante a la chaleur lors de la preparation des recettes traditionnelles