In vitro antiplasmodial activity of Brazilian Cerrado plants used as traditional remedies

Twenty-seven species of native Brazilian Cerrado plants commonly used by traditional healers to treat malaria and other diseases were collected and 204 hexanic and ethanolic extracts were obtained by maceration. The antiplasmodial activity of the extracts was tested in vitro against a chloroquine resistant strain (FcB1) of Plasmodium falciparum, and cytotoxicity against the cell lines L-6 of rats and MRC-5 of human was evaluated. Thirty-two extracts showed significant inhibition rates of Plasmodium falciparum growth and of these six showed cytotoxicity against the cell lines. The strongest antiplasmodial activity was found for the hexanic extracts of Xylopia aromatica root wood (IC(50)=4.7 microg/ml), Xylopia emarginata root bark (IC(50)=4.9 microg/ml), Casearia sylvestris var. lingua leaves, stem wood and stem bark, and root wood and root bark (IC(50) values from 0.9 to 2.3 microg/ml), and Cupania vernalis leaves (IC(50)=0.9 microg/ml); and for the ethanolic extract of Aspidosperma macrocarpon root bark (IC(50)=4.9 microg/ml). However, the best selectivity towards Plasmodium falciparum was observed for the hexanic root bark extract of Matayba guianensis (IC(50) on Plasmodium falciparum=6.1 microg/ml, SI=16.4 for MRC-5) and the ethanolic root bark extract of Aspidosperma macrocarpon (IC(50) on Plasmodium falciparum=4.9 micro/ml, SI=16.2 for MRC-5).     

A search for natural bioactive compounds in Bolivia through a multidisciplinary approach. Part VI. Evaluation of the antimalarial activity of plants used by Isoceño-Guaraní Indians

Seventy-seven plant extracts (corresponding to 62 different species) traditionally used by the Isoce?o-Guaraní, a native community living in the Bolivian Chaco, were screened for antimalarial activity in vitro on Plasmodium falciparum chloroquine sensitive strain (F32), and on ferriprotoporphyrin (FP) IX biocrystallisation inhibition test (FBIT). Among these extracts, seven displayed strong in vitro antimalarial activity, and 25 were active in the FBIT test. Positive results on both tests were recorded for six extracts: Argemone subfusiformis aerial part, Aspidosperma quebracho-blanco bark, Castela coccinea leaves and bark, Solanum argentinum leaves and Vallesia glabra bark. Results are discussed in relation with Isoce?o-Guaraní traditional medicine. Further studies to be undertaken in relation with these results are also highlighted.     

Antimalarial activity of crude extracts from nine African medicinal plants

An ethnobotanical study was conducted in Comores (Ngazidja) about plant species used traditionally for the treatment of various diseases, including malaria. Antimalarial activity of 76 vegetal extracts obtained from 17 species traditionally used to treat malaria symptoms, was evaluated in vitro using Plasmodium falciparum chloroquine-resistant strain (W2). Antiproliferative activity was evaluated on human monocytic THP1 cells and the selectivity index of the plant extracts was calculated. The results showed that 10 plant extracts had a moderate activity (5相似文献   

Antiprotozoal and cytotoxic activities in vitro of Colombian Annonaceae

Ethnobotanical and chemotaxonomical studies for antiparasitic activity of Colombian Annonaceae were carried out. In vitro antiprotozoal activity of 36 extracts obtained from six different species was determined against promastigotes of three Leishmania species, epimastigotes of Trypanosoma cruzi and both chloroquine sensitive (F32) and resistant (W2) Plasmodium falciparum. Cytotoxic activity was evaluated in U-937 cells. Active extracts were selected according their selectivity index (SI). Extracts from Annona muricata, Rollinia exsucca, Rollinia pittieri and Xylopia aromatica were active against Leishmania spp. and Trypanosoma cruzi showing IC50 values lower than 25 microg/ml. Hexane extract from Rollinia pittieri leaves was the most selective against Trypanosoma cruzi and Leishmania spp. (IS=10 and 16, respectively). The extracts from Desmopsis panamensis, Pseudomalmea boyacana, Rollinia exsucca and Rollinia pittieri showed good antiplasmodial activity (IC50 < 10 microg/ml). No correlation between antiplasmodial activity and inhibition of beta-hematin production was found. The present study gives specific and useful information about antiprotozoal and cytotoxic activities of some Annonaceae extracts. Results presented here also demonstrate which plants and/or plant parts could be useful in the treatment of leishmaniasis, Chagas' disease and malaria.     

Neuropharmacological profile of ethnomedicinal plants of Guatemala.

We carried out the Irwin's test with some different extracts of the aerial parts of Thidax procumbens L., the leaves of Neurolaena lobata (L.) R. Br., bark and leaves of Byrsonima crassifolia (L.) Kunth. and Gliricidia sepium Jacq. Walp., and root and leaves of Petiveria alliacea L. At dosage of 1.25 g dried plant/kg weight aqueous extracts of bark and leaves of Byrsonima crassifolia (L.) Kunth. and Gliricidia sepium Jacq. Walp. demonstrated the most activity: decrease in motor activity, back tonus, reversible parpebral ptosis, catalepsy and strong hypothermia. These extracts of both plants were assayed for effects on CNS and they caused very significant reductions in spontaneous locomotor activity, exploratory behavior and rectal temperature and they increased the sodium pentobarbital-induced sleeping time.     

The search for natural bioactive compounds through a multidisciplinary approach in Bolivia. Part II. Antimalarial activity of some plants used by Mosetene indians

Forty-six different species collected in the Mosetene ethnia, dwelling in the Andean Piedmont of Bolivia, were screened for antimalarial properties. Thirty-three extracts were screened for antimalarial activity in vitro on Plasmodium falciparum chloroquine resistant strain (Indo), and forty-seven extracts were evaluated in vivo on the rodent malaria P. vinckei petteri 279BY. Only two plants are specifically used in combination by the Mosetene against malaria attack (Hymenachne donacifolia and Tesseria integrifolia), but they did not display any activity in vivo at 1000 mg/kg. The in vivo most active extracts were Swietenia macrophylla bark, Trema micrantha bark and Triplaris americana bark, not all of them were used for antimalarial purposes by the Mosetene. The following extracts were moderately active: Jacaratia digitata inner bark and Momordica charantia aerial part (both traditionally used as febrifuge), Kalanchoe pinnate aerial part (used in inflammatory processes), Lunania parviflora twigs and leaves, Phyllanthus acuminatus (used as piscicide), Tynanthus schumannianus fruit (used against diarrhoea), Triumfetta semitrilobata (used as febrifuge, to alleviate kidney and gynecological pain) and finally Solanum mammosum fruit (used against scabies). We present here the results of this screening, emphazing on the in vivo antimalarial activity of the selected plants. The antimalarial in vivo activity of the selected species, in relation with their traditional Mosetene use is then discussed.     

Antimalarial activity of some plants traditionally used in treatment of malaria in Kwale district of Kenya

Methanolic and water extracts of five medicinal plant species used for treatment of malaria in traditional/cultural health systems of Kwale people in Kenya were tested for antimalarial activity against Plasmodium falciparum and Plasmodium berghei, respectively and for their cytotoxic effects. The most active extracts (IC(50)<10 microg/ml) screened against chloroquine (CQ) sensitive (D6) and resistant (W2) P. falciparum clones, were the water and methanol extracts of Maytenus undata (Thunb.) Blakelock (Celasteraceae), methanol extracts of Flueggea virosa (Willd.) Voigt (Euphorbiaceae), Maytenus putterlickioides (Loes.) Excell and Mendoca (Celastraceae), and Warburgia stuhlmannii Engl. (Canellaceae). These extracts showed various cytotoxic levels on Vero E6 cells with the water extract of M. undata exhibiting least cytotoxicity. At least one of the extracts of the plant species exhibited a high chemo suppression of parasitaemia >70% in a murine model of P. berghei infected mice. These results indicate that there is potential for isolation of a lead compound from the extracts of the five plants. W. stuhlmannii and M. putterlickioides have not been reported before for antiplasmodial activity.     

Antibacterial screening of some Peruvian medicinal plants used in Callería District

Nine ethanol extracts of Brunfelsia grandiflora (Solanaceae), Caesalpinia spinosa (Caesalpiniaceae), Dracontium loretense (Araceae), Equisetum giganteum (Equisetaceae), Maytenus macrocarpa (Celastraceae), Phyllanthus amarus (Euphorbiaceae), Piper aduncum (Piperaceae), Terminalia catappa (Combretaceae), and Uncaria tomentosa (Rubiaceae), medicinal plants traditionally used in Calleria District for treating conditions likely to be associated with microorganisms, were screened for antimicrobial activity against nine bacterial strains using the broth microdilution method. Among the plants tested, Phyllanthus amarus and Terminalia catappa showed the most promising antibacterial properties, inhibiting all of the strains tested with minimum inhibitory concentrations (MICs) ranging from 0.25 to 16 mg/ml. The extract from aerial part of Piper aduncum was significantly more active against Gram-positive (MICs ranging from 1 to 2 mg/ml) than against Gram-negative bacteria (MICs > 16 mg/ml).     

Insecticidal activity against Aedes aegypti larvae of some medicinal South American plants

The insecticidal activity of 11 extracts from nine South American medicinal plants has been studied using the Aedes aegypti larvicidal assay. Eight of the 11 plant extracts studied showed toxicity against the A. aegypti larvae (LC(50)<500 microg/ml). The dichloromethane extracts of Abuta grandifolia and Minthostachys setosa demonstrated high larvicidal activity, the most active being the dichloromethane extract of A. grandifolia, with an LC(50)=2.6 microg/ml (LC(100)= 8.1 microg/ml), indicating an activity 2-fold higher than beta-asarone, a natural botanical insecticide used as a positive control (LC(100)=16 microg/ml). On the other hand, the dichloromethane extract of M. setosa was quite potent against A. aegypti larvae showing an LC(50)=9.2 microg/ml (LC(100)=25.2 microg/ml). The results obtained suggest that the extracts of A. grandifolia and M. setosa are promising as larvicides against A. aegypti larvae and could be useful in the search for new larvicidal natural compounds.     

Brine shrimp toxicity and antiplasmodial activity of five Kenyan medicinal plants

The organic extracts of leaves and roots of five plants used for treating malaria in Central, Nairobi and Rift Valley Provinces, Kenya were tested for brine shrimp lethality and in vitro antiplasmodial activity against chloroquine sensitive and resistant strains of Plasmodium falciparum. Of the plants tested, 60% were toxic to the brine shrimp (LC(50)<30 microg/ml) and eight out of ten plant parts (80%) showed in vitro antiplasmodial activity (IC(50)<50 microg/ml). Among the extracts screened, the leaves of Cyathula polcephala had the highest toxicity to the brine shrimp (LC(50)=2.9 microg/ml) while the leaves of Pentas longiflora had the best antiplasmodial activity (IC(50)=11. /ml). The plant extracts with low IC(50) values are potential sources for novel antiplasmodial compounds.     

Antidiabetic activities of aqueous and ethanolic extracts of Piper betle leaves in rats

Leaves of Piper betle (Piperaceae) possess several bioactivities and are used in traditional medicinal systems. However, its antidiabetic activity has not been scientifically investigated so far. The aim of this study therefore, was to investigate the antidiabetic activity of Piper betle leaves. This was tested in normoglycaemic and strepozotocin (STZ)-induced diabetic rats using oral administration of hot water extract (HWE) and cold ethanolic extract (CEE). In normoglycaemic rats, both HWE and CEE significantly lowered the blood glucose level in a dose-dependent manner. In glucose tolerance test, both extracts markedly reduced the external glucose load. The antidiabetic activity of HWE is comparable to that of CEE. Moreover, HWE failed to inhibit the glucose absorption from the small intestine of rats. Both extracts were found to be non-toxic and well tolerated after following chronic oral administration (no overt signs of toxicity, hepatotoxicity or renotoxicity). However, the weight of the spleen had increased in treated groups possibly indicating lymphoproliferative activity. It is concluded that HWE and CEE of Piper betle leaves possess safe and strong antidiabetic activity.     

Medicinal plants from the Yanesha (Peru): Evaluation of the leishmanicidal and antimalarial activity of selected extracts

Aim of the study

Ninety-four ethanolic extracts of plants used medicinally by the Yanesha, an Amazonian Peruvian ethnic group, for affections related to leishmaniasis and malaria were screened in vitro against Leishmania amazonensis amastigotes and against a Plasmodium falciparum chloroquine resistant strain.

Materials and methods

The viability of Leishmania amazonensis amastigote stages was assessed by the reduction of tetrazolium salt (MTT) while the impact on Plasmodium falciparum was determined by measuring the incorporation of radio-labelled hypoxanthine.

Results and conclusions

Six plant species displayed good activity against Plasmodium falciparum chloroquine resistant strain (IC₅₀ < 10 μg/ml): a Monimiaceae, Siparuna aspera (Ruiz & Pavon), A. DC., two Zingiberaceae, Renealmia thyrsoidea (Ruiz & Pavon) Poepp. & Endl. and Renealmia alpinia (Rottb.), two Piperaceae (Piper aduncum L. and Piper sp.) and the leaves of Jacaranda copaia (Aubl.) D. Don (Bignoniaceae).Eight species displayed interesting leishmanicidal activities (IC₅₀ < 10 μg/ml): Carica papaya L. (Caricaceae), Piper dennisii Trel (Piperaceae), Hedychium coronarium J. König (Zingiberaceae), Cestrum racemosum Ruiz & Pav. (Solanaceae), Renealmia alpinia (Rottb.) Zingiberaceae, Lantana sp. (Verbenaceae), Hyptis lacustris A. St.-Hil. ex Benth. (Lamiaceae) and Calea montana Klat. (Asteraceae). Most of them are used against skin affections by Yanesha people.Results are discussed herein, according to the traditional use of the plants and compared with data obtained from the literature.     

Screening of the topical anti-inflammatory activity of some Central American plants

Hexane, chloroform and methanol extracts of seven herbal drugs used in the folk medicine of Central America against skin disorders (Aristolochia trilobata leaves and bark, Bursera simaruba bark, Hamelia patens leaves, Piper amalago leaves, and Syngonium podophyllum leaves and bark) were evaluated for their topical anti-inflammatory activity against the Croton oil-induced ear oedema in mice. Most of the extracts induced a dose-dependent oedema reduction. The chloroform extract of almost all the drugs exhibited interesting activities with ID(50) values ranging between 108 and 498 micro g/cm(2), comparable to that of indomethacin (93 micro g/cm(2)). Therefore, the tested plants are promising sources of principles with high anti-inflammatory activity.     

The in vitro and in vivo antimalarial activity of Cardiospermum halicacabum L. and Momordica foetida Schumch. Et Thonn

Two plants Cardiospermum halicacabum L. and Momordica foetida Schumch. Et Thonn traditionally used to treat symptoms of malaria in parts of East and Central Africa were screened for in vitro and in vivo antimalarial activity. Using the nitro tetrazolium blue-based parasite lactate dehydrogenase assay as used by [Makler, M.T., Ries, J.M., Williams, J.A., Bancroft, J.E., Piper, R.C., Gibbins, B.L., Hinrichs, D.J., 1993. Parasite lactate dehydrogenase as an assay for Plasmodium falciparum drug sensitivity. American Journal of Tropical Medicine and Hygiene 48, 739-741], water extracts from the two plants were found to have weak in vitro antiplasmodial activity with 50% inhibitory concentrations (IC50s) greater than 28.00 microg/ml. In vivo studies of water extracts from the two plants showed that Momordica foetida given orally in the dose range 10, 100, 200 and 500 mg/kg twice daily prolonged survival of Plasmodium berghei (Anka) infected mice from 7.0+/-1.8 to 17.9+/-1.8 days. The water extract of Cardiospermum halicacabum L was toxic to mice, none surviving beyond day 4 of oral administration, with no evidence of protection against Plasmodium berghei malaria. The study emphasizes the discrepancy that might be found between in vitro and in vivo testing of plant-derived antimalarial extracts and the need to consider in vitro antiplasmodial data with this in mind. Further studies on Momordica foetida as a source of an antimalarial remedy are indicated on the basis of these results.     

A search for natural bioactive compounds in Bolivia through a multidisciplinary approach. Part III. Evaluation Of the antimalarial activity of plants used by Alteños Indians

A total of 40 plant extracts traditionally used by the Alte?os Indians, a native community living between the Andean block and the tropical valleys of Bolivia, were screened for antimalarial activity in vitro on Plasmodium falciparum chloroquine resistant (Indo) strain, and in vivo on rodent malaria Plasmodium vinckei petteri. Eleven extracts displayed good or moderate activity in vivo, and ten extracts good or very good antimalarial activity in vitro. Results of the screening are discussed here, in relation with the traditional use of plants.     

Antimalarial activity of lactucin and lactucopicrin: sesquiterpene lactones isolated from Cichorium intybus L

Folklore reports from Afghanistan prior to the wars described the use of aqueous root extracts of Cichorium intybus (L.) as a light-sensitive plant remedy for malaria. Preparative isolation and bioassay against HB3 clone of strain Honduras-1 of Plasmodium falciparum identified the previously known light-sensitive sesquiterpene lactones Lactucin and Lactucopicrin to be antimalarial compounds.     

Antimalarial and cytotoxic activities of ethnopharmacologically selected medicinal plants from South Vietnam

Malaria is a major global public health problem and the alarming spread of drug resistance and limited number of effective drugs now available underline how important it is to discover new antimalarial compounds. An ethnopharmacological investigation was undertaken of medicinal plants traditionally used to treat malaria in the South Vietnam. Forty-nine plants were identified, 228 extracts were prepared and tested for their in vitro activity against Plasmodium falciparum, and assessed for any cytotoxicity against the human cancer cell line HeLa and the embryonic lung MRC5 cell line. In a first screening at a concentration of 10 microg/ml, 92 extracts from 46 plants showed antiplasmodial activity (parasite growth inhibition >30%). The IC(50) values of the most active extracts were determined as well as their selectivity towards Plasmodium falciparum in comparison to their cytotoxic effects against the human cell lines. Six plants showed interesting antiplasmodial activity (IC(50) ranging from 0.4 to 8.6 microg/ml) with a good selectivity: two Menispermaceae, Arcangelisia flava (L.) Merr. and Fibraurea tinctoria Lour., and also Harrisonia perforata (Blanco) Merr. (Simaroubaceae), Irvingia malayana Oliv. ex Benn. (Irvingiaceae), Elaeocarpus kontumensis Gagn. (Elaeocarpaceae) and Anneslea fragrans Wall. (Theaceae).     

Evaluation of Senegalese plants used in malaria treatment: focus on Chrozophora senegalensis

An ethnobotanical study was conducted in the Dakar area of Senegal to investigate the species used in the treatment of malaria. Seven plants are principally used: Cissampelos mucronata, Maytenus senegalensis, Terminalia macroptera, Bidens engleri, Ceratotheca sesamoides, Chrozophora senegalensis and Mitracarpus scaber. From a bibliographic study, it had been shown that the Cissampelos mucronata, Maytenus senegalensis and Terminalia macroptera have already been studied by several authors, and so only Bidens engleri, Ceratotheca sesamoides, Chrozophora senegalensis and Mitracarpus scaber were evaluated in the present study. For each plant, extracts were prepared with different solvents and tested in vitro on two chloroquine-resistant Plasmodium falciparum strains. Crude extracts from the leaves and the stems of Chrozophora senegalensis showed the best in vitro results. The IC(50) value of an aqueous extract of Chrozophora senegalensis was 1.6 microg/ml without cytotoxicity. The in vivo antiplasmodial activity of Chrozophora extracts was determined by both the oral and the intraperitoneal ways. The stages of Plasmodium cycle targeted by Chrozophora were then studied in vitro. These results could justify the traditional use of this plant in malaria treatment.     

In vitro antiprotozoal activities and cytotoxicity of some selected Cameroonian medicinal plants

Eight extracts from seven selected Cameroonian medicinal plants, traditionally used to treat malaria and other protozoal diseases, were tested in vitro for their antiprotozoal activities against Plasmodium falciparum K1 chloroquine-resistant strain, Leishmania donovani, Trypanosoma cruzi and Trypanosoma brucei rhodesiense, protozoa responsible for malaria, visceral leishmaniasis, Chagas disease and African trypanosomiasis, respectively. The most active extract against Plasmodium falciparum K1 strain and Trypanosoma brucei rhodesiense was the methanolic extract of Albizia zygia (Fabaceae) stem bark with IC(50) values of 1.0 microg/ml and 0.2 microg/ml, respectively. Five extracts showed IC(50) values below 5mug/ml against Leishmania donovani, with the methanolic seed extract of Harungana madagascarensis showing the highest activity, but only the methanolic extract of Albizia zygia showed activity against Trypanosoma cruzi. Cytotoxicity and selectivity indexes were estimated for the most active extracts. The best ratio of cytotoxicity to antiplasmodial activity (SI(a)=14) was established for the methanolic leaf extract of Symphonia globulifera (Clusiaceae), while the methanolic stem bark extract of Albizia zygia showed the best ratio of cytotoxicity to antitrypanosomal activity (SI(b)=22.5).