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1.
Rev. argent. microbiol ; Rev. argent. microbiol;49(1): 3-6, mar. 2017. ilus, tab
Artículo en Inglés | LILACS | ID: biblio-1041774

RESUMEN

Antibiotic resistance results in higher medical costs, prolonged hospital stays and increased mortality and is rising to dangerously high levels in all parts of the world. Therefore, this study aims to search for new antimicrobial agents through bioprospecting of extracts of endophytic fungi from Bauhinia guianensis, a typical Amazonian plant used in combating infections. Seventeen (17) fungi were isolated and as result the methanolic extract of the fungus Exserohilum rostratum showed good activity against the bacteria tested. The polyketide monocerin was isolated by the chromatographic technique, identified by NMR and MS, showing broad antimicrobial spectrum.


La resistencia a los antibióticos conduce a mayores costos médicos, hospitalizaciones prolongadas e incremento de la mortalidad, y está aumentando a niveles peligrosamente altos en todas partes del mundo. Este estudio tuvo como objetivo la búsqueda de nuevos agentes antimicrobianos a través de la bioprospección de extractos de hongos endófitos de Bauhinia guianensis, una planta amazónica típica, utilizada en la lucha contra problemas infecciosos. Fueron aislados 17 hongos; el extracto metanólico del hongo Exserohilum rostratum mostró buena actividad contra las bacterias probadas. Se aisló monocerina policétido por la técnica de cromatografía; este compuesto fue identificado por RM y EM, y mostró un amplio espectro antimicrobiano.


Asunto(s)
Bauhinia/microbiología , Endófitos/aislamiento & purificación , Policétidos/aislamiento & purificación , Hongos/efectos de los fármacos , Antiinfecciosos/análisis , Antibacterianos/análisis , Farmacorresistencia Microbiana/efectos de los fármacos , Cromatografía/métodos , Bioprospección/métodos
2.
Rev Argent Microbiol ; 49(1): 3-6, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28094064

RESUMEN

Antibiotic resistance results in higher medical costs, prolonged hospital stays and increased mortality and is rising to dangerously high levels in all parts of the world. Therefore, this study aims to search for new antimicrobial agents through bioprospecting of extracts of endophytic fungi from Bauhinia guianensis, a typical Amazonian plant used in combating infections. Seventeen (17) fungi were isolated and as result the methanolic extract of the fungus Exserohilum rostratum showed good activity against the bacteria tested. The polyketide monocerin was isolated by the chromatographic technique, identified by NMR and MS, showing broad antimicrobial spectrum.


Asunto(s)
Antiinfecciosos , Bauhinia , Bioprospección , Antiinfecciosos/farmacología , Fabaceae , Hongos , Pruebas de Sensibilidad Microbiana
3.
An Acad Bras Cienc ; 88(1): 29-33, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26871501

RESUMEN

The present work reports the isolation of eight compounds fromPestalotiopsis sp. EJC07 isolated as endophytic fromBauhinia guianensis, a tipical plant of the Amazon. The compounds (4S)-4,8-dihydroxy-1-tetralone (1), uracil (2), uridin (3), p-hydroxybenzoic acid (4), ergosterol (5), ergosterol peroxide (6), cerevisterol (7) and ducitol (8) were isolated by chromatographic procedures and identified by spectral methods of 1D and 2D NMR and MS. The compound 1 is being reported for the first time in the genusPestalotiopsis.


Asunto(s)
Bauhinia/química , Endófitos/química , Extractos Vegetales/química , Bauhinia/clasificación , Cromatografía de Gases y Espectrometría de Masas , Estructura Molecular
4.
An Acad Bras Cienc ; 85(4): 1247-53, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24141408

RESUMEN

The present work reports the isolation of five compounds from Aspergillus sp EJC08 isolated as endophytic from Bauhinia guianensis, a tipical plant of the Amazon. The compounds ergosterol (1), ergosterol peroxide (2), mevalolactone (3), monomethylsulochrin (4) and trypacidin A (5) were isolated by chromatographic procedures and identified by spectral methods of 1D and 2D NMR and MS. Compounds 3, 4 and 5 were tested against Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis and Staphylococcus aureus and showed good activity.


Asunto(s)
Antibacterianos/farmacología , Aspergillus/química , Bauhinia/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas , Pruebas de Sensibilidad Microbiana
5.
An Acad Bras Cienc ; 85(3): 909-12, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23969848

RESUMEN

In this work we are reporting the isolation by classical methods of chromatography of six polyketides from Penicillium herquei. The compounds citreorosein ( 1) , emodin ( 2) , janthinone ( 3) , citrinin ( 4) , citrinin H1 ( 5) and dicitrinol ( 6) were identified by spectral methods of 1D and 2D NMR and MS. Compounds 1, 2 and 3 were tested against promastigotes forms of Leishmania brasiliensis and 1 and 2 were also assayed against Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis and showed good activity.


Asunto(s)
Bacillus subtilis/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Leishmania braziliensis/efectos de los fármacos , Penicillium/química , Policétidos/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Antraquinonas/farmacología , Citrinina/farmacología , Emodina/farmacología , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Pruebas de Sensibilidad Parasitaria
6.
Nat Prod Res ; 27(4-5): 364-70, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22708684

RESUMEN

The chemical study of Aparisthmium cordatum (Euphorbiaceae) led to the isolation of tannins, together with the alkaloid ricinine and other common compounds. The composition of A. cordatum is similar to most of the Alchornea species, from the same subtribe, except for the occurrence of ricinine. This study rectifies the first investigations published for A. cordatum that were conducted with Croton palanostigma.


Asunto(s)
Alcaloides/química , Euphorbiaceae/química , Piridonas/química , Ácido Elágico/química , Extractos Vegetales/química , Taninos/química , Triterpenos/química
7.
Parasitol Res ; 107(5): 1075-81, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20661748

RESUMEN

The antiproliferative effect of julocrotine, an alkaloid isolated from Croton pullei var. glabrior (Euphorbiaceae), was studied in the macrophage amastigote and promastigote stages of the protozoan Leishmania (L.) amazonensis, which causes cutaneous leishmaniasis in the New World. Julocrotine showed a dose-dependent effect against the amastigote and promastigote forms, where 79 µM julocrotine inhibited promastigote growth by 54%, with an IC50 of 67 µM. To analyze the antiamastigote activity of the drug, murine peritoneal macrophages infected with L. amazonensis promastigotes were treated with different concentrations of julocrotine. An 80% inhibition of amastigote development was observed using 79 µM julocrotine for 72 h, with an IC50 of 19.8 µM. In addition, ultrastructural observation of the parasites showed a significant reduction in the number of amastigotes in the parasitophorous vacuoles and morphological changes in promastigotes, such as swelling of the mitochondrion, chromatin condensation, presence of membranous structures near the Golgi complex, and some vesicle bodies in the flagellar pocket. A colorimetric assay (MTT), which measures cytotoxic metabolic activity, showed that macrophages maintain their viability after treatment with the drug. These results suggest that julocrotine effectively inhibits the growth of parasites and does not have any cytototoxic effects on the host cell.


Asunto(s)
Alcaloides/farmacología , Antiprotozoarios/farmacología , Croton/química , Leishmania/efectos de los fármacos , Piperidonas/farmacología , Alcaloides/aislamiento & purificación , Animales , Antiprotozoarios/aislamiento & purificación , Colorimetría/métodos , Relación Dosis-Respuesta a Droga , Concentración 50 Inhibidora , Leishmania/ultraestructura , Macrófagos/parasitología , Ratones , Viabilidad Microbiana , Microscopía Electrónica de Transmisión , Orgánulos/ultraestructura , Parasitología/métodos , Piperidonas/aislamiento & purificación , Sales de Tetrazolio/metabolismo , Tiazoles/metabolismo
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