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1.
Nat Prod Res ; 35(16): 2691-2699, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31530021

RESUMO

Chagas disease is an illness caused by the protozoan parasite Trypanosoma cruzi. Only two drugs are available, with the drawback of low rate of cure in the chronic phase of the disease and undesirable side effects. These facts highlight the need to find new compounds for Chagas disease chemotherapy. We describe the isolation and identification of an inseparable mixture of two new trixikingolides from Trixis vauthieri, a plant from family Asteraceae, which present outstanding in vitro trypanocidal activity, with IC50 value of 0.053 µM against the intracellular trypomastigotes and amastigotes forms of T. cruzi infecting L929 cells. The IC50 of the mixture against the host cells is 68 times higher and about 70 times more potent than benznidazole, the reference drug used as control at the experiments. The next step, which depends on obtaining larger quantities of the mixture, is to test it on mice infected with T. cruzi.


Assuntos
Asteraceae , Doença de Chagas , Tripanossomicidas , Trypanosoma cruzi , Animais , Asteraceae/química , Doença de Chagas/tratamento farmacológico , Camundongos , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Tripanossomicidas/isolamento & purificação , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos
3.
Biotechnol Biofuels ; 5(1): 29, 2012 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-22559210

RESUMO

BACKGROUND: The microbial bioemulsifiers was surface active compounds, are more effective in stabilizing oil-in-water emulsions. The yeasts have been isolated to produce bioemulsifiers from vegetable oils and industrial wastes. RESULTS: Trichosporon mycotoxinivorans CLA2 is bioemulsifier-producing yeast strain isolated from effluents of the dairy industry, with ability to emulsify different hydrophobic substrates. Bioemulsifier production (mg/L) and the emulsifying activity (E24) of this strain were optimized by response surface methodology using mineral minimal medium containing refinery waste as the carbon source, which consisted of diatomaceous earth impregnated with esters from filters used in biodiesel purification. The highest bioemulsifier production occurred in mineral minimal medium containing 75 g/L biodiesel residue and 5 g/L ammonium sulfate. The highest emulsifying activity was obtained in medium containing 58 g/L biodiesel refinery residue and 4.6 g/L ammonium sulfate, and under these conditions, the model estimated an emulsifying activity of 85%. Gas chromatography and mass spectrometry analysis suggested a bioemulsifier molecule consisting of monosaccharides, predominantly xylose and mannose, and a long chain aliphatic groups composed of octadecanoic acid and hexadecanoic acid at concentrations of 48.01% and 43.16%, respectively. The carbohydrate composition as determined by GC-MS of their alditol acetate derivatives showed a larger ratio of xylose (49.27%), mannose (39.91%), and glucose (10.81%). 1 H NMR spectra confirmed by COSY suggested high molecular weight, polymeric pattern, presence of monosaccharide's and long chain aliphatic groups in the bioemulsifier molecule. CONCLUSIONS: The biodiesel residue is an economical substrate, therefore seems to be very promising for the low-cost production of active emulsifiers in the emulsification of aromatics, aliphatic hydrocarbons, and kerosene.

4.
Fitoterapia ; 82(7): 969-75, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21641971

RESUMO

An investigation of the ethanolic extract from stems of Caesalpinia echinata Lam (Leguminosae-Caesalpinioideae) led to the isolation of five new cassane diterpenes along with known lambertianic acid. Their structures were determined based on spectroscopic methods. A preliminary study on leishmanicidal activity demonstrated that compounds 1, 2 and 6 were found to inhibit the growth of amastigote-like forms of Leishmania amazonensis without affecting mononuclear cells obtained from human peripheral blood.


Assuntos
Caesalpinia/química , Ácidos Carboxílicos/farmacologia , Diterpenos/isolamento & purificação , Naftalenos/farmacologia , Extratos Vegetais/farmacologia , Tripanossomicidas/farmacologia , Ácidos Carboxílicos/química , Ácidos Carboxílicos/isolamento & purificação , Diterpenos/química , Leishmania/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Estrutura Molecular , Naftalenos/química , Naftalenos/isolamento & purificação , Extratos Vegetais/química , Caules de Planta , Tripanossomicidas/química , Tripanossomicidas/isolamento & purificação
5.
Pharm Biol ; 48(4): 388-96, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20645716

RESUMO

Paracoccidioidomycosis (PCM) is a systemic granulomatous disease caused by Paracoccidioides brasiliensis Almeida (Onygenales) that requires 1-2 years of treatment. In the absence of drug therapy, the disease is usually fatal, highlighting the need for the identification of safer, novel, and more effective antifungal compounds. With this need in mind, several plants employed in Brazilian traditional medicine were assayed on P. brasiliensis and murine macrophages. Extracts were prepared from 10 plant species: Inga spp. Mill. (Leguminosae), Schinus terebinthifolius Raddi (Anacardiaceae), Punica granatum L. (Punicaceae), Alternanthera brasiliana Kuntze (Amaranthaceae), Piper regnellii CDC. (Piperaceae), P. abutiloides Kunth (Piperaceae), Herissantia crispa L. Briz. (Malvaceae), Rubus urticaefolius Poir (Rosaceae), Rumex acetosa L. (Polygonaceae), and Baccharis dracunculifolia DC. (Asteraceae). Hexane fractions from hydroalcoholic extracts of Piper regnellii and Baccharis dracunculifolia were the most active against the fungus, displaying minimum inhibitory concentration (MIC) values of 7.8 microg/mL and 7.8-30 mug/mL, respectively. Additionally, neither of the extracts exhibited any apparent cytotoxic effects on murine macrophages at 20 microg/mL. Analyses of these fractions using gas chromatography-mass spectrometry (GC-MS) showed that the major components of B. dracunculifolia were ethyl hydrocinnamate (14.35%) and spathulenol (16.02%), while the major components of the hexane fraction of Piper regnellii were 1-methoxy-4-(1-propenyl) benzene (21.94%) and apiol (21.29%). The activities of these fractions against P. brasiliensis without evidence of cytotoxicity to macrophages justify their investigation as a potential source of new chemical agents for the treatment of PCM.


Assuntos
Antifúngicos , Medicina Tradicional/métodos , Paracoccidioides/efeitos dos fármacos , Extratos Vegetais , Plantas Medicinais/química , Animais , Antifúngicos/efeitos adversos , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Brasil , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Macrófagos/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Paracoccidioides/crescimento & desenvolvimento , Extratos Vegetais/efeitos adversos , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/farmacologia
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