RESUMO
Surinamensin, a neolignan isolated from Virola surinamensis, 3,4,5-trimethoxy-8-[2',6'-dimethoxy-4'-(E)-propenylphenoxy]-phenylpropane, a neolignan isolated from Virola pavonis, and 25 of its synthetic analogues or correlated substances with ether linkages and their corresponding C-8 sulphur and nitrogen analogues, were tested for activity against Leishmania donovani amastigotes and promastigotes in vitro. Some were active against L. donovani promastigotes at 30 microM but inactive against intracellular amastigotes. The natural neolignan from V. pavonis was active against promastigotes at 100 microM. The highest selective activity was found in those compounds with sulphur bridges. The beta-ketosulfide (3,4-dimethoxy)-8-(4'-methylthiophenoxy)-propiophenone produced 42% inhibition of L. donovani amastigotes in the liver of BALB/c mice at 100 mg/kg given once daily for five consecutive days (P>0.05).
Assuntos
Anisóis/farmacologia , Antiprotozoários/farmacologia , Leishmania donovani/efeitos dos fármacos , Lignanas/farmacologia , Magnoliopsida/química , Animais , Anisóis/química , Anisóis/isolamento & purificação , Antiprotozoários/química , Antiprotozoários/isolamento & purificação , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Feminino , Leishmaniose Visceral/tratamento farmacológico , Lignanas/química , Lignanas/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB CRESUMO
Bioactivity-directed fractionation of the CHCl3-MeOH extract of the leaves of Celaenodendron mexicanum by means of the brine shrimp lethality test and chromatographic techniques led to the isolation of three carboxylic acid triterpenes, the new tirucalla-type triterpene, 3 alpha-hydroxytirucalla-7,24Z-dien-26-oic acid, 3-oxotirucalla-7,24Z-dien-26-oic acid, and epi-oleanolic acid, and three biflavonoids amentoflavone, podocarpusflavone A, and podocarpusflavone B. Four non-active compounds friedelin, maytensifolin B, 3 beta-hydroxyfriedelan-16-one, and celaenodendrolide were also obtained. epi-Oleanolic acid was the most active against brine shrimps with LC50 value of 23.3 microM. In addition, all isolates were tested for in vitro antiprotozoal and cytotoxic activities. 3-Oxotirucalla-7,24Z-dien-26-oic acid and epi-oleanolic acid showed the highest activity against Leishmania donovani promastigotes with IC50 values of 13.7 and 18.8 microM, respectively. Only 3-oxotirucalla-7,24Z-dien-26-oic acid showed activity against Trypanosoma brucei brucei bloodstream forms with IC50 value of 16.8 microM.
Assuntos
Antiprotozoários/isolamento & purificação , Euphorbiaceae/química , Flavonoides/isolamento & purificação , Triterpenos/isolamento & purificação , Animais , Antiprotozoários/química , Antiprotozoários/farmacologia , Flavonoides/química , Flavonoides/farmacologia , Concentração Inibidora 50 , Leishmania donovani/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Folhas de Planta/química , Plasmodium falciparum/efeitos dos fármacos , Triterpenos/química , Triterpenos/farmacologia , Trypanosoma brucei brucei/efeitos dos fármacosRESUMO
Medicinal plants are an important health resource in many regions of the Americas and are of particular importance to many Indian communities. Based on a recent ethnobotanical study in Mexico, we investigated the activity of 29 plant extracts against Entamoeba histolytica, three bacteria (Bacillus subtilis, Escherichia coli, and Micrococcus luteus) and two fungi (Cladosporium cucumerinum and Penicillium oxalicum). After separation of these extracts between CH2Cl2 and H2O the resulting phases were also evaluated.
Assuntos
Amebicidas/farmacologia , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Indígenas Centro-Americanos , Extratos Vegetais/farmacologia , Plantas Medicinais/microbiologia , Plantas Medicinais/parasitologia , Humanos , Medicina Tradicional , México , Testes de Sensibilidade MicrobianaRESUMO
Extracts prepared from Simarouba amara fruits collected in Panama have been found to be active against Plasmodium falciparum in vitro and against Plasmodium berghei in mice. Four active quassinoids have been identified as ailanthinone, 2'-acetylglaucarubinone, glaucarubinone and holacanthone.