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1.
Talanta ; 164: 490-502, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28107963

RESUMEN

Erectile dysfunction (ED) is a sexual disorder characterized by the inability to achieve or maintain a sufficiently rigid erection. Despite the availability of non-invasive oral treatment options, many patients turn to herbal alternatives. Furthermore, herbal supplements are increasingly gaining popularity in industrialized countries and, as a consequence, quality control is a highly important issue. Unfortunately, this is not a simple task since plants are often crushed and mixed with other plants, which complicates their identification by usage of classical approaches such as microscopy. The aim of this study was to explore the potential use of chromatographic fingerprinting to identify plants present in herbal preparations intended for the treatment of ED. To achieve this goal, a HPLC-PDA and a HPLC-MS method were developed, using a full factorial experimental design in order to acquire characteristic fingerprints of three plants which are potentially beneficial for treating ED: Epimedium spp., Pausinystalia yohimbe and Tribulus terrestris. The full factorial design demonstrated that for all three plant references a C8 column (250mm×4.6mm; 5µm particle size) is best suited; methanol and an ammonium formate buffer (pH 3) were found to be the best constituents for the mobile phase. The suitability of this strategy was demonstrated by analysing several self-made triturations in three different botanical matrices, which mimic the influential effects that could be expected when analysing herbal supplements. To conclude, this study demonstrates that chromatographic fingerprinting could provide a useful means to identify plants in a complex herbal mixture.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos/análisis , Fraude/prevención & control , Espectrometría de Masas
2.
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
3.
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
4.
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
5.
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
6.
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
7.
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
8.
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
9.
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
10.
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
11.
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
12.
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
13.
J Ethnopharmacol ; 102(1): 89-94, 2005 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-15996841

RESUMEN

Methanol and water extracts of the root of Epinetrum villosum (Exell) Troupin (Menispermaceae) were found to exhibit antimicrobial and antiplasmodial activities. Investigation of the active methanol fraction led to the isolation of four bisbenzylisoquinoline alkaloids, i.e., cycleanine, cycleanine N-oxide, isochondodendrine and cocsoline. Structures were established by spectroscopic methods. Cocsoline displayed antibacterial and antifungal activities (MIC values of 1000-15.62 and 31.25 microg/ml, respectively). Isochondodendrine was found to have the most potent antiplasmodial activity (IC50 = 0.10 microg/ml), whereas the IC50 on HCT-116 human colon carcinoma cells was 17.5 microg/ml (selectivity index 175). Cycleanine acted against HIV-2 (EC50=1.83 microg/ml) but was at least 10-fold less active against HIV-1. Cycleanine N-oxide showed no activity towards all tested microorganisms.


Asunto(s)
Alcaloides/farmacología , Antibacterianos/farmacología , Fármacos Anti-VIH/farmacología , Antifúngicos/farmacología , Antimaláricos/farmacología , Bencilisoquinolinas/farmacología , Menispermaceae , Extractos Vegetales/farmacología , Raíces de Plantas/química , Animales , Células HCT116 , Humanos , Pruebas de Sensibilidad Microbiana , Plasmodium falciparum/efectos de los fármacos
14.
Ann Trop Med Parasitol ; 99(4): 345-57, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15949182

RESUMEN

The antimalarial activities of crude extracts and 17 fractions from the partition of 80%-methanolic extracts of three plants (the stem bark of Croton mubango, the stem bark of Nauclea pobeguinii and the leaves of Pyrenacantha staudtii) used as antimalarial remedies in the Democratic Republic of Congo were studied both in vitro (against Plasmodium falciparum) and in mice infected with Pl. berghei berghei. The toxic effects of dried aqueous extracts of the plants were also investigated, in uninfected mice. The most active crude extracts in vitro, with median inhibitory concentrations (IC(50)) of <1 microg/ml, were found to be the methanolic and dichloromethane extracts of C. mubango, and the dichloromethane extracts of N. pobeguinii and Py. staudtii. The aqueous extract with the most antimalarial activity in vitro was that of C. mubango (IC(50) = 3.2 microg/ml), followed by that of N. probeguinii (IC(50) = 5.3 microg/ml) and then that of Py. staudii (IC(50) = 15.2 microg/ml). Results from the in-vivo tests of antimalarial activity showed that, at a daily oral dose of 200 mg/kg, all the dichloromethane extracts, the petroleum-ether, chloroformic, ethyl-acetate and residual water-soluble fractions from C. mubango, and the chloroformic, ethyl-acetate and n-butanolic fractions from Py. staudtii produced >80% chemosuppression of the parasitaemias by day 4. The aqueous extracts of C. mubango and N. probeguinii produced a slightly lower but still significant inhibition of parasitaemia (60%-80%) whereas that of Py. staudtii only suppressed the day-4 parasitaemias by 37%. The dried aqueous extract of the stem bark of C. mubango showed some signs of toxicity in mice, with median lethal doses (LD(50)) of 350 mg/kg in the female mice and 900 mg/kg in the male. The extract significantly increased the serum concentrations of glutamate-oxaloacetate transaminase (GOT) and glutamate-pyruvate transaminase (GPT) in mice of both sexes, but had no effect on the blood levels of creatinine or urea. No significant toxic effect was observed for the dried aqueous extracts of N. pobeguinii and Py. staudtii (LD(50) >5 g/kg). Neither of these extracts affected the serum concentrations of GPT or the blood concentrations of creatinine and urea, although the N. pobeguinii extract did increase the serum concentration of GOT.


Asunto(s)
Antimaláricos/uso terapéutico , Malaria/tratamiento farmacológico , Fitoterapia/métodos , Animales , Aspartato Aminotransferasas/sangre , Creatinina/sangre , Croton/química , Femenino , Masculino , Ratones , Fitoterapia/efectos adversos , Extractos Vegetales/efectos adversos , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Plasmodium berghei/efectos de los fármacos , Plasmodium falciparum/efectos de los fármacos , Rubiaceae/química , Pruebas de Toxicidad Aguda/métodos , Urea/sangre
15.
J Ethnopharmacol ; 95(2-3): 399-404, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15507366

RESUMEN

The ethanolic extracts from fresh apical stems of Phyllanthus niruri L. (Euphorbiaceae) cultured on Murashige and Skoog (MS) medium supplemented with IBA/BAP/Coco nucifera L. milk for 1, 2, 4 and 6 months were phytochemically and biologically investigated and compared with intact plant part and whole plant extracts. Results from the in vitro antiplasmodial testing indicated that the EtOH extract of a 1-month-old callus culture (IC(50) = 16.3 +/- 2.5 microg/ml) exhibited a higher activity than the ethanolic extracts of the fresh apical stem (IC(50) = 18.2 +/- 2.4 microg/ml) and callus cultures of 2-, 4- and 6-months-old (25 microg/ml < IC(50) < 40 microg/ml). These activities were however lower than that displayed by the ethanolic extract of the whole plant (IC(50) < 3 microg/ml). The EtOH extract of 1-month-old callus culture (the most active) was fractionated with solvents of different polarities. Its CH(2)Cl(2) fraction rich in terpenic constituents (IC(50) = 9.2 +/- 3.4 microg/ml) exhibited a higher antiplasmodial activity than its isoamylic alcohol fraction obtained at pH 2-3 (IC(50) = 25.6 +/- 2.3 microg/ml) rich in flavonoids. The activity of these two fractions was lower than that displayed by the same fractions from the whole plant (2 microg/ml < IC(50) < 3 microg/ml). Alkaloidic fractions from the whole plant and 1-month-old callus culture of fresh apical stem were considered as inactive (IC(50) > 100 microg/ml).


Asunto(s)
Antimaláricos/farmacología , Phyllanthus , Plasmodium falciparum/efectos de los fármacos , Animales , Antimaláricos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Tallos de la Planta , Plasmodium falciparum/fisiología
16.
Phytother Res ; 18(9): 729-36, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15478202

RESUMEN

Different types of triterpenes including saponins and aglycons were evaluated for their ability to inhibit [3H] BQ-123 and [3H] angiotensin II binding to the human endothelin 1 ETA and angiotensin II AT1 receptors, respectively. Selectivity for only one of the two receptors was exhibited by asiatic acid and its saponins (ETA) and oleanolic acid (AT1). To a lesser extent betulinic acid, beta-amyrin and friedelin also showed selectivity for the ETA receptor. To address the question whether the effect of saponins on cell membranes might interfere with the normal binding of specific radioligands to their receptors, the activity of saponins with different haemolytic properties were compared. Highly haemolytic saponins such as alpha-hederin and beta-escine showed partial (60%) inhibition of radioligand-binding to the ETA receptor and complete inhibition (100%) to the AT1 receptor. Moreover, the haemolytically inactive kryptoescine, at the same concentration, caused complete inhibiton of radioligand-binding to both receptors, indicating that inhibition of receptor binding was not related to the membrane-interacting properties of saponins.


Asunto(s)
Fitoterapia , Extractos Vegetales/farmacología , Plantas Medicinales , Receptor de Angiotensina Tipo 1/efectos de los fármacos , Receptor de Endotelina A/efectos de los fármacos , Animales , Unión Competitiva/efectos de los fármacos , Células CHO , Cricetinae , Cricetulus , Femenino , Humanos , Extractos Vegetales/administración & dosificación , Ensayo de Unión Radioligante , Saponinas/administración & dosificación , Saponinas/farmacología , Triterpenos/administración & dosificación , Triterpenos/farmacología
17.
J Ethnopharmacol ; 93(1): 27-32, 2004 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15182900

RESUMEN

The in vitro antiplasmodial activity of seven EtOH extracts and twenty fractions from the partition of the initial ethanolic extracts from seven African medicinal plants used in the Democratic Republic of Congo (DR Congo) for the treatment of malaria was evaluated. The most active EtOH extracts (IC50 < 3 microg/ml) were those from Cassia occidentalis leaves, Euphorbia hirta whole plant, Garcinia kola stem bark and Phyllanthus niruri whole plant. Their respective petroleum ether soluble fractions also exhibited an antiplasmodial activity with IC50 < 3 microg/ml. EtOH extracts from Vernonia amygdalina leaves (5 < IC50 < 10 microg/ml), Tetracera poggei leaves (10 < IC50 < 50 microg/ml) and Morinda morindoides leaves (50 < IC50 < 100 microg/ml) were less active, but their petroleum ether fractions exhibited a pronounced antiplasmodial activity (IC50 < 3 microg/ml). The same observation could also be made for the petroleum ether fraction from Cassia occidentalis, Euphorbia hirta, Garcinia kola and Phyllanthus niruri. Isoamyl alcohol fractions from Euphorbia hirta, Phyllanthus niruri and Vernonia amygdalina showed IC50) values less than 3 microg/ml, and from Cassia occidentalis, Garcinia kola, Morinda morindoides and Tetracera poggei between 10 and 50 microg/ml. The observed antiplasmodial activity may be related to the presence of terpenes, steroids, coumarins, flavonoids, phenolic acids, lignans, xanthones and anthraquinones.


Asunto(s)
Antimaláricos/farmacología , Plantas Medicinales , Plasmodium falciparum/efectos de los fármacos , Animales , Antimaláricos/aislamiento & purificación , República Democrática del Congo , Humanos , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Estructuras de las Plantas , Plasmodium falciparum/fisiología
18.
Phytomedicine ; 9(1): 56-61, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11924765

RESUMEN

Forty-two ethanolic extracts of thirty-six Rwandan medicinal plants were investigated for their influence on complement-mediated hemolysis. The plants were selected on the base of their ethnomedicinal use in infections and autoimmune diseases. Eight plant extracts showed an inhibitory activity against the classical pathway of the complement system and ten plant extracts against the alternative pathway. Three plant extracts exhibited an interesting activity against both pathways, i.e. Aspilia pluriseta, Coleus kilimandschari, and Macaranga kilimandscharica (leaves and stem). Further study indicated that the complement inhibitory activity was not caused by chelation of bivalent cations or by direct action on the target erythrocytes.


Asunto(s)
Activación de Complemento , Eritrocitos/efectos de los fármacos , Hemólisis/efectos de los fármacos , Medicinas Tradicionales Africanas , Fitoterapia , Extractos Vegetales/farmacología , Humanos , Concentración 50 Inhibidora , Estructuras de las Plantas , Rwanda
19.
Phytomedicine ; 9(1): 62-8, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11924766

RESUMEN

Selected plants used in Rwandan traditional medicine for the treatment of infections and/or rheumatoid diseases were investigated for antiviral activity in vitro against human immunodeficiency virus type-1 (HIV-1). Of the 38 tested 80% ethanolic extracts, belonging to plants of 21 different families only the extracts from the leaves of Aspilia pluriseta (Asteraceae) and Rumex bequaertii (Polygonaceae) had interesting selectivity indices (SI = ratio of the 50% cytotoxic concentration to the 50% effective antiviral concentration) higher than 1. Further fractionation of the initially antivirally inactive ethanolic extract of Tithonia diversifolia, however, led to an aqueous fraction with a high anti-HIV-1 activity (SI > 461), indicating that the cytotoxicity of some plant components may mask the antiviral properties of the active plant substances in total plant extracts.


Asunto(s)
Fármacos Anti-VIH/farmacología , VIH-1/efectos de los fármacos , Medicinas Tradicionales Africanas , Fitoterapia , Extractos Vegetales/farmacología , Fármacos Anti-VIH/uso terapéutico , Línea Celular/efectos de los fármacos , Infecciones por VIH/tratamiento farmacológico , Humanos , Extractos Vegetales/uso terapéutico , Estructuras de las Plantas , Rwanda
20.
J Ethnopharmacol ; 79(2): 155-63, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11801376

RESUMEN

A total of 45 Rwandan plant extracts, belonging to 37 different plant species out of 21 families, were investigated for their antibacterial, antifungal, and antiviral properties. The plants were selected on the base of their ethnomedicinal use against infections and autoimmune diseases. From all the plant extracts tested, only Clematis hirsuta (leaves) showed a pronounced antifungal activity against Candida albicans and the dermatophytes Trichophyton rubrum, Epidermophyton floccosum, and Microsporum canis. Seven plant extracts showed a high antiviral activity against the DNA-virus Herpes simplex type 1, while five and three plant extracts were highly active against the RNA-viruses Coxsackie and Polio, respectively. Only Macaranga kilimandscharica (leaves) showed an interesting anti-measles activity, whereas Eriosema montanum (leaves) and Entada abyssinica (leaves) were highly active against Semliki forest virus. Some plant extracts showed an antibacterial activity against Gram-positive bacteria and Mycobacterium fortuitum, but none of them were active against the Gram-negative bacteria tested.


Asunto(s)
Antiinfecciosos/farmacología , Antivirales/farmacología , Evaluación Preclínica de Medicamentos/métodos , Medicinas Tradicionales Africanas , Extractos Vegetales/farmacología , Antibacterianos , Antiinfecciosos/uso terapéutico , Antifúngicos/farmacología , Antifúngicos/uso terapéutico , Antivirales/uso terapéutico , Evaluación Preclínica de Medicamentos/estadística & datos numéricos , Fitoterapia/métodos , Fitoterapia/estadística & datos numéricos , Extractos Vegetales/uso terapéutico , Hojas de la Planta/química , Rwanda
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