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1.
Heliyon ; 8(8): e10226, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36090217

RESUMEN

Leaves from Adhatoda vasica Nees, Acanthaceae (synonym Justicia adhatoda L.) have been widely used in traditional medicine for their beneficial effect in the treatment of respiratory diseases. Vasicine, the main quinazoline alkaloid in A. vasica, has been linked to its medicinal properties. The purpose of this work was to develop and validate a reliable analytical method for the quantification of vasicine in A. vasica leaves and commercially available products. For this purpose, a high-performance liquid chromatography method coupled to diode array detection (HPLC-DAD) was used. After optimization of the extraction process and the HPLC conditions, linearity, precision, accuracy, and specificity were checked. During the validation, six commonly available food supplements and dosage forms were tested using the validated method. The calibration model was found to be linear in the concentration range of 5.125-205 µg/mL. The average vasicine content at different concentration levels was 0.99 g/100 g with an RSD% of 0.05%. The average recovery was found to be 102.3% with an RSD of 4.3%. Additionally, it was confirmed that the validated method was still precise and accurate for quantifying vasicine in other matrices like the tested preparations. In summary, the validated method was suitable for the determination of vasicine in leaves of Adhatoda vasica, as well as for investigating the quality and the prescribed intake of several commercial products.

2.
J Ethnopharmacol ; 231: 73-79, 2019 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-30056206

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Hypertension is an important public health challenge in low- and middle-income countries, and in many African countries including Guinea medicinal plants are still widely used for its treatment. MATERIALS AND METHODS: The objective of this study was to determine the prevalence of hypertension in two Guinean urban districts (Pounthioun and Dowsare), to describe its management and to collect information on traditional herbal remedies. A total of 316 participants entered the study, 28.2% (89/316) men and 71.8% (227/316) women. Of these, 181 were from Dowsare (50 men and 131 women) and 135 from Pounthioun (39 men and 96 women). The mean age of subjects was 40.8 ±â€¯14.0 years (range18 - 88years), while the majority of subjects (63.3% or 200/316) were 45-74 years old. RESULTS: The overall prevalence of hypertension was 44.9% (142/316): 46.4% (84/181) from Dowsare and 43.0% (58/135) from Pounthioun. Ethnobotanical investigations among hypertensive patients led to the collection of 15 plant species, among which Hymenocardia acida leaves and Uapaca togoensis stem bark were the most cited. Phytochemical investigation of these two plant species led to the isolation and identification of isovitexin and isoorientin from H. acida, and betulinic acid and lupeol from U. togoensis. CONCLUSION: The presence of these constituents in Hymenocardia acida leaves and Uapaca togoensis stem bark may at least in part support their traditional use against hypertension in Guinea.


Asunto(s)
Hipertensión/tratamiento farmacológico , Medicinas Tradicionales Africanas , Plantas Medicinales , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Etnobotánica , Femenino , Guinea/epidemiología , Humanos , Hipertensión/epidemiología , Masculino , Persona de Mediana Edad , Fitoterapia , Prevalencia , Adulto Joven
3.
Phytother Res ; 32(9): 1750-1754, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29726034

RESUMEN

The flavonoids comprise a large class of plant metabolites distributed in food plants. These compounds have antioxidant, antitumor, antiallergic, and anti­inflammatory effects. The molecular mechanisms of their biological activities remain to be clearly understood. We investigated the in vitro anti­inflammatory potential of a flavonoid mixture and isolated compounds from the leaves of Boldoa purpurascens. Our results provide direct evidence of the anti­inflammatory effects of the mixture, which are mediated by the inhibition of the proinflammatory cytokines tumor necrosis factor α and interleukin 6 as well as the modulation of the expression of cyclooxygenase 2.


Asunto(s)
Inhibidores de la Ciclooxigenasa/farmacología , Flavonoides/farmacología , Interleucina-6/metabolismo , Macrófagos/efectos de los fármacos , Nyctaginaceae/química , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Antiinflamatorios/farmacología , Ciclooxigenasa 2/metabolismo , Lipopolisacáridos , Ratones , Ratones Endogámicos C57BL , Estructura Molecular , Extractos Vegetales/farmacología , Hojas de la Planta/química
4.
J Ethnopharmacol ; 193: 510-516, 2016 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-27693770

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The Nkundo people (Nkundo area of Bolongo, Mai-Ndombe district, Bandundu Province, DR Congo) use various plant parts of the tree Greenwayodendron suaveolens (Engl. & Diels) Verdc. (syn. Polyalthia suaveolens Engl. & Diels) (Annonaceae) against malaria, but its antiprotozoal constituents are not known. MATERIALS AND METHODS: The crude 80% ethanol extract from the fruits, leaves, root bark and stem bark and 16 fractions were assessed in vitro for their antiprotozoal activity against Trypanosoma brucei brucei, T. cruzi, Leishmania infantum and the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum (Pf-K1). Their cytotoxic effects were evaluated against MRC-5 cells. Active constituents were isolated by chromatographic means, identified using spectroscopic methods, and evaluated in the same assays. RESULTS: The root bark extract showed the highest activity against P. falciparum K1 (IC50 0.26µg/mL) along with the stem bark alkaloid fraction (IC50 0.27µg/mL). The root bark alkaloid fraction had a pronounced activity against all selected protozoa with IC50 values <1µg/mL. The 90% methanol fractions of the different plant parts showed a pronounced activity against P. falciparum K1, with IC50 values ranging between 0.36µg/mL and 0.69µg/mL. Four constituents were isolated: the triterpenes polycarpol, and dihydropolycarpol, the latter one being reported for the first time from nature, and the alkaloids polyalthenol and N-acetyl-polyveoline. They were active to a various degree against one or more protozoa, mostly accompanied by cytotoxicity. The highest selectivity was observed for N-acetyl-polyveoline against P. falciparum K1 (IC50 2.8µM, selectivity index 10.9). CONCLUSIONS: These results may explain at least in part the traditional use of this plant species against parasitic diseases such as malaria in DR Congo.


Asunto(s)
Antimaláricos/farmacología , Fitoquímicos/farmacología , Extractos Vegetales/farmacología , Plasmodium falciparum/efectos de los fármacos , Polyalthia/química , Tripanocidas/farmacología , Antimaláricos/aislamiento & purificación , Antimaláricos/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Frutas/química , Humanos , Concentración 50 Inhibidora , Leishmania infantum/efectos de los fármacos , Leishmania infantum/crecimiento & desarrollo , Pruebas de Sensibilidad Parasitaria , Fitoquímicos/aislamiento & purificación , Fitoquímicos/toxicidad , Fitoterapia , Corteza de la Planta/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/toxicidad , Hojas de la Planta/química , Raíces de Plantas/química , Plantas Medicinales , Plasmodium falciparum/crecimiento & desarrollo , Tripanocidas/aislamiento & purificación , Tripanocidas/toxicidad , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma brucei brucei/crecimiento & desarrollo
5.
J Ethnopharmacol ; 192: 302-308, 2016 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-27394387

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Boldoa purpurascens Cav. (Nyctaginaceae) is a plant species used in traditional medicine in Cuba as a diuretic. AIM OF THE STUDY: The aim of the present investigation was to evaluate the safety profile of a hydroalcoholic extract from leaves of Boldoa purpurascens. MATERIALS AND METHODS: First, an experimental study to assess the oral acute toxicity at a dose of 2000mg/kg body weight of the extract was carried out. Potential genotoxicity of the extract was evaluated using the Ames test and the micronucleus induction assay in mouse bone marrow. In the Ames test a concentration range of 50, 100, 150, 300 and 500µg/plate was tested. In the micronucleus induction assay, doses of 500, 1000 and 2000mg/kg of body weight were tested. For completeness, since the extract contains saponins, the evaluation of the hemolytic activity, ocular and skin irritation were included. RESULTS: No signs or symptoms of toxicity were observed in the oral acute toxicity test (body weight at baseline, seven days and end of the experiment of 236.41±20.07, 256.81±30.44 and 240.02±26.16 respectively for the treated group). The hydroalcoholic extract from the leaves was not mutagenic in the Ames test, and no genotoxicity was observed in the micronucleus assay. A hemolysis test at concentration of 1mg/mL confirmed hemolytic activity, which is not a safety concern since saponins are not absorbed after oral administration. In order to evaluate the percentage of protein denaturation, the ocular irritability index was calculated. The extract was found to be irritating. Finally, skin irritability was evaluated and the irritation index was equal to zero. CONCLUSIONS: Based on the toxicological evaluation of a traditionally used hydroalcoholic extract from the leaves of Boldoa purpurascens we can confirm the safety of its oral use.


Asunto(s)
Nyctaginaceae/toxicidad , Extractos Vegetales/toxicidad , Hojas de la Planta/toxicidad , Administración Oral , Animales , Células de la Médula Ósea/efectos de los fármacos , Células de la Médula Ósea/patología , ADN Bacteriano/efectos de los fármacos , ADN Bacteriano/genética , Dermatitis por Contacto/etiología , Dermatitis por Contacto/patología , Ojo/efectos de los fármacos , Ojo/metabolismo , Proteínas del Ojo/metabolismo , Femenino , Hemólisis/efectos de los fármacos , Masculino , Ratones Endogámicos BALB C , Micronúcleos con Defecto Cromosómico/inducido químicamente , Pruebas de Micronúcleos , Mutación , Nyctaginaceae/química , Fitoterapia , Extractos Vegetales/administración & dosificación , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta/química , Plantas Medicinales , Desnaturalización Proteica , Conejos , Ratas Sprague-Dawley , Ratas Wistar , Medición de Riesgo , Pruebas de Irritación de la Piel , Solventes/química , Factores de Tiempo , Pruebas de Toxicidad Aguda
6.
J Ethnopharmacol ; 182: 137-49, 2016 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-26900129

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The recent outbreak of Ebola virus infections has mostly remained confined to the West African countries Guinea-Conakry, Sierra-Leone and Liberia. Due to intense national and international mobilizations, a significant reduction in Ebola virus transmission has been recorded. While international efforts focus on new vaccines, medicines and diagnostics, no coherent national or international approach exists to integrate the potential of the traditional health practitioners (THPs) in the management of infectious diseases epidemics. Nevertheless, the first contact of most of the Ebola infected patients is with the THPs since the symptoms are similar to those of common traditionally treated diseases or symptoms such as malaria, hemorrhagic syndrome, typhoid or other gastrointestinal diseases, fever and vomiting. MATERIALS AND METHODS: In an ethnomedical survey conducted in the 4 main Guinean regions contacts were established with a total of 113 THPs. The socio-demographic characteristics, the professional status and the traditional perception of Ebola Virus Disease (EVD) were recorded. RESULTS: The traditional treatment of the main symptoms was based on 47 vegetal recipes which were focused on the treatment of diarrhea (22 recipes), fever (22 recipes), vomiting (2 recipes), external antiseptic (2 recipes), hemorrhagic syndrome (2 recipes), convulsion and dysentery (one recipe each). An ethnobotanical survey led to the collection of 54 plant species from which 44 identified belonging to 26 families. The most represented families were Euphorbiaceae, Caesalpiniaceae and Rubiaceae. Literature data on the twelve most cited plant species tends to corroborate their traditional use and to highlight their pharmacological potential. CONCLUSIONS: It is worth to document all available knowledge on the traditional management of EVD-like symptoms in order to evaluate systematically the anti-Ebola potential of Guinean plant species.


Asunto(s)
Personal de Salud , Fiebre Hemorrágica Ebola/tratamiento farmacológico , Medicina Tradicional , Adulto , Anciano , Anciano de 80 o más Años , Brotes de Enfermedades/prevención & control , Ebolavirus , Etnobotánica , Femenino , Guinea , Conocimientos, Actitudes y Práctica en Salud , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Humanos , Masculino , Persona de Mediana Edad
7.
J Ethnopharmacol ; 174: 187-94, 2015 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-26239153

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Isolona hexaloba (Pierre) Engl. and Diels (Annonaceae) is traditionally used in D.R. Congo against parasitic diseases including malaria. MATERIALS AND METHODS: Two crude aqueous extracts, 3 crude methanol extracts and 3 crude 80% ethanol extracts from the leaves, root bark and stem bark together with 12 subfractions from the crude 80% ethanol extracts were evaluated in vitro for their antiprotozoal activity against Trypanosoma brucei brucei, T. cruzi, Leishmania infantum and the chloroquine and pyrimethamine resistant K1 strain of Plasmodium falciparum. Their cytotoxic effects against MRC-5 cell lines were also assessed. RESULTS: Results indicated that the most pronounced activities against T. b. brucei were recorded for the crude methanol extracts of root bark (IC50=1.97 µg/ml; SI>32.49) and leaves (IC50=2.65 µg/ml; SI>24.15). Three samples displayed good activity against T. cruzi: the 80% methanol extract of leaves (IC50=8.33 µg/ml; SI>3.92), its petroleum ether fraction (IC50=8.50 µg/ml; SI=2.52) and the crude aqueous extract of the stem bark (IC50=9.31 µg/ml; SI=3.46). The crude aqueous extract of the leaves exhibited a pronounced and selective activity against L. infantum (IC50=2.00 µg/ml; SI>32). The crude methanol extract of leaves (IC50=6.35 µg/ml; SI>10.10) and the 2 dichloromethane soluble fractions of the 80% ethanol extracts from root bark (IC50=6.96 µg/ml; SI=6.1) and stem bark (IC50=8 µg/ml; SI>8.00) showed good activity and selectivity against L. infantum. The most active samples against Plasmodium falciparum K1 were the leaves crude 80% ethanol extract (0.92 µg/ml) and its fractions: alkaline aqueous (IC50=0.27 µg/ml), 90% methanol (0.90 µg/ml) and dichloromethane (1.04 µg/ml), respectively, with promising selectivity indexes of 35

Asunto(s)
Annonaceae , Antiprotozoarios/toxicidad , Corteza de la Planta , Extractos Vegetales/toxicidad , Hojas de la Planta , Raíces de Plantas , Animales , Antiprotozoarios/aislamiento & purificación , Leishmania infantum/efectos de los fármacos , Ratones , Extractos Vegetales/aislamiento & purificación , Tallos de la Planta , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos
8.
J Ethnopharmacol ; 150(3): 1145-53, 2013 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-24184265

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The objective of the present study was to collect and document information on herbal remedies traditionally used for the treatment of malaria in Guinea. MATERIALS AND METHODS: The survey was carried out from May 2008 to September 2010 and targeted traditional medical practitioners and herbalists. The questionnaire and oral interviews were based on the standardized model which was prepared by the "Centre de Recherche et de Valorisation des Plantes Médicinales (CRVPM) - Dubréka". RESULTS AND DISCUSSION: A total of 258 people (141 males and 117 females) from which 150 traditional healers and 108 herbalists were interviewed. The age of informants ranged from 28 to 82 years old. 57% (149/258) of the interviewees were more than 50 years old. The respondents had good knowledge of the symptoms of malaria, and a fairly good understanding of the causes. One hundred thirteen plant species were recorded, out of which 109 were identified. They belonged to 84 genera and 46 families. The most frequently cited plants were Vismia guineensis, Parkia biglobosa, Nauclea latifolia, Harungana madagascariensis, Terminalia macroptera, Crossopteryx febrifuga, Terminalia albida, Annona senegalensis, and Nauclea pobeguinii. The leaves were most frequently used (80/113 species), followed by stem bark (38/113 species) and roots (4/113 species). The remedies were mostly prepared by decoction (111 species), followed by maceration (seven species). Only one species was prepared by infusion. CONCLUSION: The present study showed that traditional healers in Guinea have a consistent knowledge of antimalarial plants. Further research should be carried out to compare the anti-malarial activity of the different species, and to check if their use against malaria can be scientifically validated.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria/tratamiento farmacológico , Medicinas Tradicionales Africanas , Fitoterapia , Plantas Medicinales , Adulto , Anciano , Etnobotánica , Femenino , Guinea , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
9.
J Ethnopharmacol ; 149(2): 438-42, 2013 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-23876596

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: To evaluate the in vitro antiplasmodial activity and cytotoxicity, and the in vivo activity of extracts and fractions from the leaves, root-bark and stem-bark of Triclisia gilletii (De Wild) Staner (Menispermaceae), used in traditional medicine against malaria. MATERIALS AND METHODS: The aqueous and 80% MeOH extracts, and a series of fractions and subfractions from the leaves, stem and root-bark of Triclisia gilletii were tested in vitro for their antiplasmodial activity against a Congolese-sensitive strain of Plasmodium falciparum, against the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum, for cytotoxicity against MRC-5 cells, and in vivo in mice infected with Plasmodium berghei berghei. RESULTS: Many samples from the three plant parts exhibited pronounced activity against the Congolese chloroquine-sensitive strain of Plasmodium falciparum with some IC50 values <0.02 µg/ml, and against the K1 strain, with some IC50 <0.25; the selectivity was higher against the Congolese strain. At oral doses of 200 and 400mg/kg body weight in infected mice, the aqueous, 80% methanol and total alkaloid extracts from the three plant parts produced more than 65% and 75% chemosuppression, respectively. The antiplasmodial activity of these three plant parts of Triclisia gilletii can at least in part be attributed to bisbenzylisoquinoline alkaloids, and supports its use for the treatment of uncomplicated malaria in traditional medicine.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria/tratamiento farmacológico , Menispermaceae , Parasitemia/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Animales , Antimaláricos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Cloroquina , Resistencia a Múltiples Medicamentos , Humanos , Malaria/parasitología , Ratones , Parasitemia/parasitología , Corteza de la Planta , Extractos Vegetales/farmacología , Hojas de la Planta , Raíces de Plantas , Plasmodium berghei/aislamiento & purificación , Plasmodium falciparum/efectos de los fármacos , Pirimetamina
10.
J Ethnopharmacol ; 148(2): 724-7, 2013 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-23612422

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: To evaluate the antiprotozoal activity and cytotoxicity of extracts and fractions from the leaves, root bark and stem bark of Alstonia congensis (Apocynaceae), used in traditional medicine against parasitic diseases. MATERIALS AND METHODS: The aqueous and 80% MeOH extracts, and a series of fractions and subfractions from the leaves, stem and root bark of Alstonia congensis were tested in vitro for their antiprotozoal activity against Trypanosoma brucei brucei, Trypanosoma cruzi, Lesihamania infantum and the chloroquine and pyrimethamine-resistant K1 strain of Plasmodium falciparum. Their cytotoxicity on MRC-5 cells (human lung fibroblasts) was evaluated as well. RESULTS: The aqueous and 80% MeOH extracts and a series of subfractions of each plant part exhibited pronounced antiprotozoal activity against the K1 strain of Plasmodium falciparum with IC50 values ranging from 2 to 5 µg/ml, and good activity against Trypanosoma brucei brucei and Trypanosoma cruzi with IC50 values ranging between 5 and 10 µg/ml. The residual 80% MeOH extract from the leaves, and the total alkaloid extract from stem and root bark were the only subfractions active against Leishmania infantum with IC50 values <10 µg/ml. None of the samples from the root bark was cytotoxic against MRC-cell lines (CC50>64 µg/ml). In general, the aqueous extract (traditional decoction) showed the highest selectivity, especially against Plasmodium falciparum. CONCLUSION: These results can partly support and justify the traditional use of these plant parts of Alstonina congensis as raw materials for the preparation of traditional remedies to treat parasitic diseases such as malaria and trypanosomiasis.


Asunto(s)
Alstonia/química , Antiprotozoarios/farmacología , Extractos Vegetales/farmacología , Antiprotozoarios/química , Línea Celular , Etnofarmacología/métodos , Fibroblastos/efectos de los fármacos , Humanos , Concentración 50 Inhibidora , Leishmania infantum/efectos de los fármacos , Pulmón/efectos de los fármacos , Pruebas de Sensibilidad Parasitaria/métodos , Fitoterapia/métodos , Extractos Vegetales/química , Plasmodium falciparum/efectos de los fármacos , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos
11.
Phytother Res ; 27(5): 721-4, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-22807273

RESUMEN

In order to investigate the potential use of Boldoa purpurascens against diabetes, the antihyperglycemic effect of an ethanol extract obtained from its leaves was evaluated at doses of 50, 100 and 200 mg/kg in rats after induction of hyperglycemia by alloxan. Insulin 5 IU/kg was used as positive control and NaCl 0.9% as negative control. A similar experiment was performed with the aqueous extract used at doses of 50 and 100 mg/kg using metformin at a dose of 50mg/kg as positive control. Statistical analysis was carried using the Kruskal-Wallis test with an interval of trust of 99%. The ethanolic and aqueous extract of B. purpurascens showed a significant decrease of blood glucose levels 72 h after administration. Phytochemical analysis of the ethanol extract showed the presence of D-pinitol, a compound known for its hypoglycemic properties. In conclusion, ethanolic as well as aqueous extracts of B. purpurascens leaves show antihyperglycemic activity, possibly due to the presence of D-pinitol and flavonoids.


Asunto(s)
Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/farmacología , Nyctaginaceae/química , Extractos Vegetales/farmacología , Animales , Glucemia/análisis , Inositol/análogos & derivados , Inositol/química , Inositol/farmacología , Masculino , Metformina/uso terapéutico , Extractos Vegetales/química , Hojas de la Planta/química , Ratas , Ratas Wistar
12.
J Ethnopharmacol ; 142(3): 620-6, 2012 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-22609154

RESUMEN

AIM OF THE STUDY: To evaluate the antidiarrhoeal properties of Alstonia congensis leaves claimed to be effective for the treatment of diarrhoea by traditional healers during our ethnopharmacological investigation conducted in Kinshasa, Democratic Republic of Congo. MATERIALS AND METHODS: The aqueous extract (decoction), and the 80% hot methanol extract (Soxhlet extraction) were obtained. This last extract was fractionated. The antidiarrhoeal activity was evaluated using castor oil and magnesium sulphate-induced diarrhoea in animals. The potential antibacterial activity of all samples was also assessed in vitro. RESULTS: At all oral doses of 100 and 200 mg/kg body weight, all A. congensis samples showed significant and dose-dependent antidiarrhoeal activity in treated Wistar rats characterised by significant increase of onset time and decrease of all other diarrhoeal parameters at various degrees compared to untreated groups in both models. At the highest oral dose of 200 mg/kg bodyweight, the 80% hot methanol and aqueous extracts produced 79.8 ± 2.1% and 78.6 ± 0.5%, and 75.0 ± 2.1% and 71.4 ± 2.1% inhibition of defecation and diarrhoea respectively against castor oil-induced diarrhoea, and 75.0 ± 1.2% and 73.3±1.2% inhibition of diarrhoea respectively against magnesium sulphate-induced diarrhoea. The 80% hot methanol and aqueous detannified extracts showed low activity (42-47% inhibition of defecation and/or diarrhoea in both tests) suggesting that tannins may be responsible for the observed activity. At the same oral doses, the total alkaloid extract, the chloroform soluble fraction rich in alkaloids, the 80% methanol and the alkaline aqueous soluble subfractions produced more than 50% inhibition of defecation and/or diarrhoea in both tests. From the antibacterial testing in vitro, results indicated that all A. congensis samples exhibited an antibacterial activity mainly against bacteria implicated in diarrhoea with MIC and MBC values in the range of 15.6-500 µg/ml. The most active samples were the aqueous (decoction) and the 80% hot methanol dried extracts, the chloroform subfraction rich in alkaloids and the total alkaloid extract (MIC: 15.7-125 µg/ml, MBC: 31.2-250 µg/ml). Proteus varibilis was found to be the most resistant microorganism. CONCLUSION: These reported results can partly support and justify the traditional use of extracts from Alstonia congensis leaves for the treatment of diarrhoea in tradittional medicine.


Asunto(s)
Alstonia , Antibacterianos/uso terapéutico , Antidiarreicos/uso terapéutico , Diarrea/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Animales , Antibacterianos/farmacología , Antidiarreicos/farmacología , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Aceite de Ricino , Diarrea/inducido químicamente , Sulfato de Magnesio , Metanol/química , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/farmacología , Hojas de la Planta/química , Ratas , Ratas Wistar , Solventes/química
13.
J Ethnopharmacol ; 141(1): 301-8, 2012 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-22394563

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: The antiprotozoal and cytotoxic activity of the aqueous extracts from 33 medicinal plants, used by traditional healers for the treatment of various parasitic diseases and collected after an ethnopharmacological inventory conducted in the Bolongo area, Bandundu province in DR Congo, was evaluated. MATERIALS AND METHODS: Decoctions were prepared, lyophilized and evaluated for in vitro antiprotozoal activity against Trypanosoma b. brucei, Trypanosoma cruzi, Leishmania infantum, and the chloroquine- and pyrimethamine-resistant K1 strain of Plasmodium falciparum. Cytotoxicity against MRC-5 cells was included to assess selectivity of activity. RESULTS: Most of the tested extracts exhibited pronounced (IC(50)≤5µg/ml) or good (5

Asunto(s)
Antiprotozoarios/farmacología , Etnofarmacología , Extractos Vegetales/farmacología , Antimaláricos/farmacología , Antiprotozoarios/aislamiento & purificación , Antiprotozoarios/uso terapéutico , Antiprotozoarios/toxicidad , Línea Celular , Supervivencia Celular/efectos de los fármacos , República Democrática del Congo , Relación Dosis-Respuesta a Droga , Humanos , Concentración 50 Inhibidora , Leishmania infantum/efectos de los fármacos , Medicinas Tradicionales Africanas , Pruebas de Sensibilidad Parasitaria , Fitoterapia , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/uso terapéutico , Extractos Vegetales/toxicidad , Plantas Medicinales , Plasmodium falciparum/efectos de los fármacos , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos
14.
J Ethnopharmacol ; 127(2): 215-20, 2010 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-19951738

RESUMEN

AIM: The study was aimed to evaluate the in vitro antispasmodic activity of Morinda morindoides leaves aqueous extract, its soluble fractions and isolated compounds to provide the pharmacological basis for its use for the treatment of constipation and diarrhoea in traditional medicine. METHODS: The antispasmodic activity of each sample was evaluated on acetylcholine (ACh) and the depolarized KCl solution induced contractions on guinea-pig isolated ileum suspended in Tyrode's solution. RESULTS: At a test concentration of 40mug/ml in organ bath, the aqueous extract and its petroleum ether soluble fraction showed a spasmogenic effect on both agonists. The diethylether, ethyl acetate, n-butanol and residual aqueous phase soluble fractions from the partition of the aqueous extract exhibited spasmolytic activity producing 47-100% inhibition of contractions induced by both agonists with IC(50) values ranged from 6 to 15 microg/ml according to the case. In addition, the n-butanol and residual aqueous phase soluble fractions showed an inhibitory effect of 75 and 66% respectively on low high [K(+)] (25 mM) and 65 and 60% respectively on high [K+] (80 mM). Crude flavonoids showed spasmolytic on both agonists while crude saponins only showed spasmolytic activity on ACh and displayed spasmogenic effect on KCl. Quercetin, quercitrin and rutin exhibited significant antispasmodic effect with IC(50) values <0.1 microg/ml. Epoxygaertneroside and gaertneroside showed good antispasmodic activity on both agonists (4

Asunto(s)
Morinda , Parasimpatolíticos/farmacología , Extractos Vegetales/farmacología , Hojas de la Planta , Animales , Relación Dosis-Respuesta a Droga , Femenino , Cobayas , Íleon/efectos de los fármacos , Íleon/fisiología , Masculino , Parasimpatolíticos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Rubiaceae
15.
Talanta ; 76(2): 462-8, 2008 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-18585307

RESUMEN

A new method was developed and validated for the quantification of strictosamide in the extract of the stem bark of Nauclea pobeguinii. This plant belongs to the Rubiaceae family and is widely used in the African traditional medicine against malaria and malaria-like symptoms. Alkaloids are suspected to be responsible for the antimalarial activity. One of these alkaloids is strictosamide, already reported to be the major constituent in the root bark of this plant. Because strictosamide was not commercially available another alkaloid, ajmalicine HCl, with comparable properties was used as a secondary standard. The samples of the dried 80% ethanol extract from the stem bark of N. pobeguinii were purified on C(18) solid phase extraction cartridges and analysed using HPLC-UV. The strictosamide used for the validation of the correction factor for response was isolated and purified by means of preparative HPLC and TLC. Although the relative standard deviation (R.S.D.) of 2.6% was still acceptable, the response factor was determined for every analysis based on the ratio of the peak area of strictosamide compared to the peak area of ajmalicine HCl in a concentration of 0.01 mg/ml. The precision of the method according to the time and the concentration, had a R.S.D. value of 2.2% and 2.6%, respectively. The recovery of the method was 92.2% (R.S.D. of 9.4%) which was acceptable. The method has been proven to be suitable for the determination of alkaloids in the extract of the stem bark of N. pobeguinii, according to the ICH guidelines on the validation of analytical methods.


Asunto(s)
Alcaloides/análisis , Cromatografía Líquida de Alta Presión/métodos , Medicinas Tradicionales Africanas , Rubiaceae/química , Antimaláricos/análisis , Cromatografía Líquida de Alta Presión/normas , Corteza de la Planta/química , Extractos Vegetales/análisis , Reproducibilidad de los Resultados
16.
J Ethnopharmacol ; 115(3): 409-15, 2008 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-18068320

RESUMEN

AIM OF THE STUDY: To evaluate in vitro the antiprotozoal and cytotoxic activities of 80% methanol extract from 45 medicinal plants collected in Sankuru (Democratic Republic of Congo) against Trypanosoma brucei brucei, Trypanosoma cruzi and the chloroquine-sensitive Ghanaian strain of Plasmodium falciparum, and MRC-5 cell lines respectively. MATERIAL AND METHODS: Different extracts were obtained by maceration of each plant part used with 80% methanol for 24h. The mixture was filtered and evaporated in vacuo to give corresponding dried extract. The activity against Trypanosoma brucei brucei and Trypanosoma cruzi were performed in 96 well tissue plates each containing 10 microl aqueous plant extract dilutions (100 to 0.01 microg/ml) with 10 microl of the parasite suspension cultured in Hirumi medium supplemented with 10% foetal calf serum, a solution of 2% penicillin/streptomycin (2% P/S) After 4 days incubation with Almar blueâ solution, fluorescence was measured at 500 nm emission and 530 nm excitation and results expressed as percentage reduction in parasite compared to control wells. The antiplasmodial activity of was assessed in vitro against the chloroquine-sensitive Ghanaian strain of Plasmodium falciparum cultured in RPMI-1640 medium by the lactate deshydrogenase assay in the presence of plant extracts (50 to 0.01 microg/ml). Cell-lines MRC-5 were cultured in MEM medium supplemented with 20mM l-glutamine, 16.5mM NaHCO(3), 5% foetal calf serum and 2% P/S solution. After 4h incubation, cell proliferation/viability was spectrophotomecally assessed at 540 nm after addition of MTT. In each assay, the IC50 value for each sample was derived by the drug concentration-response curves. RESULTS: The extracts from Alcornea cordifolia leaves, Momordica charantia whole plant, Omphalocarpum glomerata, root bark and Piptadia africanum stem bark showed good antiprotozoal activity against Trypanosoma brucei brucei with IC50 values from 0.7 to 7 microg/ml. Only Piptadenia africanum extract showed a pronounced antiprotozoal activity against Trypanosoma cruzi (IC50=4.0+/-06 microg/ml). The extracts from Alchornea cordifolia, Polyathia swaveleons stem bark, Sapium cornutum stem bark and Triclisia giletii stem bark exhibited a pronounced antiplasmodial activity against P. falciparum Ghanaian strain with IC50 values ranging from 0.5 to 3.0 microg/ml. Piptadenia africanum extract was the most cytotoxic sample (CC50=0.25 microg/ml) with poor selectivity against all selected protozoa (SI<10) while other active extracts did not show a significant cytotoxic effect against MCR-5 cell-lines with good selectivity according to the case. CONCLUSION: These active plant extracts are selected for extensive studies leading to the isolation of active constituents.


Asunto(s)
Antineoplásicos/farmacología , Antiprotozoarios/farmacología , Extractos Vegetales/farmacología , Animales , Antineoplásicos/aislamiento & purificación , Antiprotozoarios/aislamiento & purificación , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , República Democrática del Congo , Fibroblastos/efectos de los fármacos , Fibroblastos/metabolismo , Humanos , Concentración 50 Inhibidora , Medicinas Tradicionales Africanas , Ratones , Pruebas de Sensibilidad Parasitaria , Plantas Medicinales , Plasmodium falciparum/efectos de los fármacos , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos
17.
J Ethnopharmacol ; 115(1): 25-9, 2008 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-17942256

RESUMEN

Alchornea cordifolia is one of the most widely-used plants in traditional medicine throughout Africa, principally for inflammatory, antimicrobial and parasitic diseases. In continuation of our investigations on its anti-inflammatory activity, we fractionated the leaf and root bark extracts and isolated six compounds which exhibited significant topical anti-inflammatory activity in the mouse ear oedema model using croton oil at a dose of 90 microg/cm2. Daucosterol (2), acetyl aleuritolic acid (4), N1,N2-diisopentenyl guanidine (5) and N1,N2,N3-triisopentenyl guanidine (6) were shown to be more active than indomethacin, while beta-sitosterol (1) and di(2-ethylhexyl) phthalate (3) were less effective. This is the first report on the presence of compounds 1, 2, 3 and 4 in this plant and of the anti-inflammatory activity of 3, 5 and 6. These compounds may account, at least in part, for the use of A. cordifolia in folk medicine to treat inflammation.


Asunto(s)
Antiinflamatorios/farmacología , Euphorbiaceae/química , Extractos Vegetales/farmacología , Animales , Antiinflamatorios/química , Antiinflamatorios/aislamiento & purificación , Modelos Animales de Enfermedad , Oído , Edema/inducido químicamente , Edema/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Masculino , Medicinas Tradicionales Africanas , Ratones , Extractos Vegetales/química , Hojas de la Planta , Raíces de Plantas
18.
J Ethnopharmacol ; 114(1): 44-53, 2007 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-17825510

RESUMEN

A total of 418 healers have been interviewed in Guinea, a coastal country of West Africa, ranging between 7 degrees 30 and 12 degrees 30 of northern latitude and 8 degrees and 15 degrees of western longitude. Plant species used by the local inhabitants to treat infectious diseases were identified using ethnobotanical, ethnographic and taxonomic methods. During these investigations, 218 plants were registered, of which the following were the most frequently used: Erythrina senegalensis, Bridelia ferruginea, Crossopteryx febrifuga, Ximenia americana, Annona senegalensis, Cochlospermum tinctorium, Cochlospermum planchonii, Lantana camara, Costus afer, Psidium guajava, Terminalia glaucescens, Uapaca somon and Swartzia madagascariensis. Most plants, and especially the leaves, were essentially used as a decoction. In order to assess antibacterial activity, 190 recipes were prepared and biologically tested, among which six showed activity (minimal inhibitory concentration<125 microg/ml) against Bacillus cereus, Mycobacterium fortuitum, Staphylococcus aureus, or Candida albicans, i.e., Entada africana, Chlorophora regia, Erythrina senegalensis, Harrisonia abyssinica, Uvaria tomentosa, and a mixture of six plants consisting of Swartzia madagascariensis, Isoberlinia doka, Annona senegalensis, Gardenia ternifolia, Terminalia glaucescens and Erythrina senegalensis.


Asunto(s)
Antibacterianos/farmacología , Medicinas Tradicionales Africanas , Extractos Vegetales/farmacología , Plantas Medicinales/química , Adulto , Anciano , Antibacterianos/aislamiento & purificación , Recolección de Datos , Femenino , Guinea , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Extractos Vegetales/aislamiento & purificación , Estructuras de las Plantas
19.
Curr Med Chem ; 14(4): 417-30, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17305543

RESUMEN

Over the last decade, much research has focused on the potential health benefits of antioxidants and indeed many synthetic and natural compounds have been evaluated for their antioxidant profile. However, in several studies only a limited number of assays, often poorly validated, are used and the techniques available frequently lack specificity. These limitations may incorrectly influence the results. This review will therefore focus on several pitfalls that may emerge in vitro and in vivo antioxidant research. First, different in vitro techniques to determine antioxidant potential are discussed, including radical scavenging assays and fingerprinting methods. As a rule, a panel of different assays is indispensable to characterize and establish in vitro antioxidant activity. Furthermore, as problems of absorption, distribution, metabolism and excretion are only accounted for by in vivo studies, the need for in vivo antioxidant research is pointed out. Several methods to characterize the in vivo activity of antioxidants, including major drawbacks and pitfalls of some assays, have been discussed. The availability of both a representative "oxidative stress" animal model and a battery of well-validated assays to assess the broad diversity of oxidative damage and antioxidative defence parameters, are crucial for antioxidant research in vivo.


Asunto(s)
Antioxidantes/uso terapéutico , Investigación Biomédica , Evaluación Preclínica de Medicamentos/métodos , Animales , Antioxidantes/farmacocinética , Antioxidantes/farmacología , Humanos , Estrés Oxidativo/efectos de los fármacos
20.
J Ethnopharmacol ; 107(1): 83-90, 2006 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-16603327

RESUMEN

An aqueous decotion (dried extract), an 80% MeOH extract from Morinda morindoides leaves, and 10 flavonoids and 4 iridoids isolated from the 80% MeOH extract were evaluated in vitro for their potential antiamoebic activity and their cytotoxic effect against MT-4 cells. Results indicated that the aqueous decoction and the 80% MeOH extract exhibited an interesting antiamoebic activity with IC(50) values of 3.1 +/- 1.7 and 1.7 +/- 0.6 microg/ml, respectively. Apigenin-7-O-glucoside and luteolin-7-O-glucoside exhibited a moderate antiamoebic activity with IC(50) values of 22.3 +/- 3.2 and 37.4 +/- 2.7 microg/ml, respectively. Kaempferol (IC(50) = 10.3 +/- 2.3 microg/ml), apigenin (IC(50) = 12.7 +/- 4.3 microg/ml), and luteolin (IC(50) = 17.8 +/- 4.3 microg/ml) showed a more pronounced activity than their corresponding glycosides. All tested iridoids displayed a very good activity with IC(50) values less than 10 microg/ml. The most active iridoids were epoxygaertneroside (IC(50) = 1.3 +/- 0.4 microg/ml) and methoxygaertneroside (IC(50) = 2.3. +/- 0.7), followed by gaertneroside and gaertneric acid with IC(50) values of 4.3 +/- 1.8 and 7.1 +/- 1.4 microg/ml, respectively. Except quercetin and quercetin-7,4'-dimethylether which have shown a cytotoxic effect with IC(50) ranging from 14 to 22 microg/ml. No correlation could be deduced between the observed antiamoebic and cytotoxic activity of these tested samples. A structure-activity relationship for isolated compounds is discussed. These findings support the medicinal report for the traditional use of Morinda morindoides leaves for the treatment of amoebiasis.


Asunto(s)
Amebicidas/farmacología , Entamoeba histolytica/efectos de los fármacos , Morinda/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Animales
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