ABSTRACT
Background and Aims: Manotes expansa Sol. ex Planch. and Aframomum alboviolaceum (Ridl.) Schum. are two plants belonging respectively to the family Connaraceae R.Br. and Zingiberaceae Martino widely used in traditional medicine for the treatment of eye diseases, fever, headaches, gastritis as well as asthma. The aim of the present study is the valorization of these two plants collected in the Democratic Republic of Congo by a quantitative and qualitative analysis of secondary metabolites and mineral elements in their leaves. Materials and Methods: The determination of secondary metabolites in the leaves of Manotes expansa and Aframomum alboviolaceum was carried out by UV-Visible spectrophotometry and X-ray fluorescence spectrophotometry for the identification and quantitative analysis of mineral elements. Results: The results showed that the leaves of these two plants are rich in phenolic compounds, i.e. 442.2 mgEqAG/g for the leaves of A. alboviolaceum, 370.64 mgEqAG/g for the red leaves and 282.64 mgEqAG/g green leaves of M. expansa. Although being part of the same plant, the red and green leaves of M. expansa presented a totally different phytochemical profile. The contents of condensed tannins, anthocyanins and flavonoids are respectively 0.3%, 0.68% and 3.29% for the leaves of A. alboviolaceum; 0.58%, 0.36% and 6.89% for the red leaves, and 0.65%, 0.26% and 7.55% for the green leaves of M. expansa. The mineral content in the leaves of both plants remains dominated by the high concentration of potassium (K), calcium (Ca), Magnesium (Mg), Manganese (Mn) and Iron (Fe). Conclusion: The high content of phenolic compounds and essential trace elements makes the leaves of M. expansa and A. alboviolaceum potential candidates to alleviate several health problems in Africa in general and particularly in the Democratic Republic of Congo.
ABSTRACT
Oral cavity cancers are part of the upper aerodigestive tract cancers and represent a significant burden worldwide. Its epidemiology varies from country to country with high frequencies in South East Asian countries. Tobacco and alcohol are the main risk factors. Survival of oral cancer is low i.e., less than 40% in the advanced stage (stage III and IV), diagnosis of oral cavity cancer is based on a complete clinical examination of the oral cavity complete with biopsy, bio-markers are an adjunct to screening and diagnosis of oral cavity cancers, surgery, radiotherapy, chemotherapy and immunotherapy are part of the therapeutic armamentarium of oral cancer but also have limitations. Traditional medicine is an important and proven alternative in the treatment and support of patients with oral cavity cancer. Prevention of oral cavity cancers includes not only early detection of precancerous and cancerous lesions but also control of risk factors and education of the population. Surgery, radiotherapy, chemotherapy and immunotherapy are part of the therapeutic strategy of oral cancer treatment but also have limitations. Traditional Medicine is an important and proven alternative in the treatment and support of patients with oral cavity cancer. It is thus desirable to scientifically validate phytochemicals in order to integrate alternative medicine as part of national cancer management strategy. In silico advanced studies on secondary metabolites of medicinal plants traditionally used to treat oral cancer are in progress.
ABSTRACT
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.
ABSTRACT
Aims of the Study: To identify plant species traditionally used to treat anemia in Yakoma territory and to evaluate their chemical composition. Place and Duration: Yakoma Territory (survey) and University of Kinshasa (Phytochemical study), from August and October 2019. Methods: Ethnobotanical survey according to the "snowball" sampling technique among traditional healers (based on the free consent of the respondents), chemical analyses of plant materials (chemical screening, TLC, phytomarkers content, minerals composition) according to standard methods. ED-XRF was used for mineral analysis. Microsoft Excel version 2010, Origin version 8.5 Pro and IBM SPSS statistics version 20 software packages were used for data processing and analysis. Results and Discussion: The survey showed that 18 plant species are traditionally used by Ngbandi traditional healers to treat anemia in Yakoma territory. They belong to 16 families and 17 genera. The most used organs are the leaves (68.4%) and the roots (10.5%). Decoction and infusion are the most used mode of preparation (33.3% each), followed by cooking (22.2%) and maceration (11.1%). The oral route (77.8%) is the most used mode of administration followed by the enema (16.7%) and the anal route (5.6%). Morphological types consist of herbs and trees (33.3% each) and shrubs and lianas (16.7% each). The biotope types consist of forest plants (44.4%), cultivated plants/Crops (38.9%), marshy ground plants (11.1%) and ruderal plants (5.6%). These plants belonging to five biological types: erected therophytes (44.4%), mesophanerophytes (27.8%), microphanerophytes and climbing phanerophytes (11.1% each) and lianescent phanerophytes (5.56%). These anti-anemic plant species are mostly Pantropical and Afro-tropical (39% of species each) followed by Guineo-Congolese (17% of species) and American (5%). Chemical analysis revealed the presence of alkaloids, anthocyanins, flavonoids, anthraquinones and terpenoids and various minerals including iron, zinc, copper, calcium, magnesium and manganese. Conclusion: In the current state of knowledge, the survey of anemic plants from this part of the Democratic Republic of the Congo is reported for the first time.
ABSTRACT
Objectives: The aim of this work is to carry out a phytochemical study and to evaluate in vitro antibacterial potential of the aqueous extract of Phyllanthus niruri, a plant traditionally used in Kasai Oriental (DR Congo) against various bacteriosis and non-bacterial diseases. Study Design: P. niruri, was selected from a list resulting from an ethnobotanical survey carried out in Kasai Oriental because of the number of citations and recipes involving it, the level of preference of the species as well as the diversity of diseases treated and the plebiscite of its effectiveness by local traditional healers. To contribute to the enhancement of this plant traditionally used against various bacteriosis and to confirm its potential antibacterial power, it was subjected to phytochemical screening and its aqueous extract was tested in vitro on bacterial strains. Place and Duration of the Study: The period of this research went from December 2017 to February 2018. The analyzes were carried out at the physico-chemical and microbiological analysis laboratories of the Congolese Control Office of Mbujimayi (DR Congo) and at the Biology and Chemistry laboratories of the ISP Mbujimayi. Methodology: The chemical groups of the bioactive substances were sought using the classic methods of characterization in solution by precipitation, coloring and foam reactions. The diameters of the zones of inhibition, MICs and CMBs of the aqueous extract of this plant were determined in vitro against 20 bacterial strains subjected to the test. Results: P. niruri contains various bioactive chemical groups. Its aqueous extract showed antibacterial activity in vitro against several of 20 tested bacterial strains. According to the MICs and CMBs, the inhibitory action spectrum covers 12 bacterial strains out of the 20 tested. Conclusion: The results found confirm that P. niruri has antibacterial principles and a therapeutic potential by the presence of several bioactive substances and the inhibitory power of its aqueous extract on some bacterial strains tested.
ABSTRACT
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.
ABSTRACT
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.
ABSTRACT
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.
ABSTRACT
The present paper aims to study the effect of aromatic structure on the inhibition of biogas production and more specifically the effect of para substituted anilines functional groups (chemical structure) on methane biosynthesis by the digested pig manure methanogens. The objective of this study was also to examine the structure-toxicity relationships of aromatic compounds to acetoclastic methanogens. Study Design: Anaerobic digestion of pig manure, anaerobic toxicity essay, The effects of functional group nature on inhibition of methane production by acetoclastic methanogens. Correlation of the methanogenic toxicity (IC50) with aromatic compounds hydrophobicity (logPoct). Place and Duration of Study: Department of Chemistry, University of Kinshasa (DR Congo), between August 2011 and May 2012. Methodology: The toxicity to acetoclastic methanogenic bacteria was performed with the standard method of serum bottles, digested pig manure was utilized as inoculums, acetate as substrate and the methane gas volume produced was measured by serum bottles liquid displacement systems (Mariotte flask system). Results: The obtained results indicate that relationships exist between para substituted anilines functional groups nature (chemical structure) and their inhibitory effects on methanogens. The toxicity of para bisubstituted anilines increases in the following order: SO3 < OH < H < CH3 < Cl < NO2 From this sequence of increasing toxicity, it can be seen that the methanogenic toxicity varies with the functional group nature which is in the para position of the main function. Indeed, p-Nitroaniline and benzene with 45.76 and 208.78 mg/l as IC50 values respectively were the most toxic compounds, while p-Aminophenol and p-Aminosulfonic acid (Sulfanilic acid) with 1800.39 and 2777.82 mg/l IC50 values were the less toxic. A very significant negative linear correlation between the toxicity of para substituted anilines compounds and their hydrophobicity was found. Conclusion: The results of this study indicate that relationships exist between para substituted anilines functional groups nature and their inhibitory effects in methane biosynthesis by the methanogens.
ABSTRACT
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.
ABSTRACT
Aims: The purpose of this study was to evaluate the inhibitory effects of phenolic monomers on methanogenesis in anaerobic digestion and to assess the effect of hydroxyl groups’ number of phenolic monomers (aromatic structure) on inhibition of methane production by acetoclastic methanogens (archaea). Study Design: Anaerobic digestion of pig manure, anaerobic toxicity essay, The effect of the hydroxyl group’s number on the methanogenic toxicity as exhibited by monomeric tannins, Correlation of the methanogenic toxicity (IC50) with aromatic compounds hydrophobicity (logPoct), Correlation of the methanogenic toxicity (IC50) with Cresols boiling point (bp). Place and Duration of Study: Department of Chemistry, University of Kinshasa (DR Congo), between September 2011 and May 2012. Methodology: The toxicity to acetoclastic methanogenic bacteria was performed with the standard method of serum bottles; digested pig manure was utilized as inoculums and acetate as substrate. The methane gas volume produced was measured by serum bottles liquid displacement systems (Mariotte flask system). Results: The results of this study indicate that an increase in the number of hydroxyl groups on the aromatic compound was associated with a decrease in the compound’s toxicity to methanogens (archea). The toxicity of various phenolic monomers are decreasing in the following order: pyrogallol < hydroquinone < resorcinol < phenol < benzene with 3172, 2745, 1725, 1249 and 209 mg/l IC50 values respectively. A significant negative linear correlation between the toxicity of phenolic monomers together with the reference compound (benzene) and their hydrophobicity was found. Moreover, a high positive linear correlation has been found between the IC50 values of phenolic monomers and their boiling temperatures. Conclusion: The obtained results indicate that relationships exist between the phenolic monomers structure and their inhibitory effects in methane biosynthesis. The analysis of experimental results suggests that an increase in the number of hydroxyl groups on the aromatic compounds was associated with a decrease in the phenolic monomers toxicity.
ABSTRACT
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