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ACTIVIDAD ANTIBACTERIANA DE Diplostephium tolimense Cuatrec. (ASTERACEAE) FRENTE A Staphylococcus aureus ANTIBACTERIAL ACTIVITY OF Diplostephium tolimense Cuatrec. (ASTERACEAE) AGAINST Staphylococcus aures  [cached]
Liliana áVILA,Eduard BAQUERO,Amparo VI?A,Elizabeth MURILLO
Vitae , 2006,
Abstract: Se presenta el estudio de la actividad antibacteriana de la especie vegetal Diplostephium tolimense Cuatrec. (Asteraceae), colectada en el páramo del nevado del Tolima, la cual cuenta con pocos estudios químicos y farmacológicos, al igual que muchas otras especies de este ecosistema. A partir de un extracto etanólico crudo y mediante partición biodirigida se obtiene la fracción más simple de mayor actividad frente a Staphylococcus aureus (ATCC 25923). Paralelamente se realizan análisis fitoquímicos a las porciones de mayor bioactividad obtenidas durante todo el proceso. Se observa que la acción antibacteriana se incrementa al aumentar la simplicidad química del extracto y que terpenos y flavonoides parecen estar relacionados con la acción revelada. Se trata del primer reporte, hasta la fecha conocido, de actividad antibacteriana in vitro para D. tolimense. A study of antibacterial activity of the Diplostephium tolimense Cuatrec (Asteraceae) vegetal species, which was collected in the paramo of Tolima, is presented. This species, as many others of this ecosystem, has had few chemical and pharmacological studies. The simplest fraction with the largest activity against Staphylococcus aureus (ATCC 25923), is obtained starting from a raw ethanol extract and by means of bioassay guided partition. Parallelly, phytochemical analyses to the portions of greater bioactivity, obtained during the whole process, are carried out. It is observed that antibacterial action increases as the chemical simplicity increases and that the presence of terpenes and flavonoids seems to be related with this action. This is the first report, so far well-known, of in vitro antibacterial activity for D. tolimense.
ACTIVIDAD ANTIBACTERIANA DE Diplostephium tolimense Cuatrec. (ASTERACEAE) FRENTE A Staphylococcus aureus
áVILA,Liliana; BAQUERO,Eduard; VI?A,Amparo; MURILLO,Elizabeth;
Vitae , 2006,
Abstract: a study of antibacterial activity of the diplostephium tolimense cuatrec (asteraceae) vegetal species, which was collected in the paramo of tolima, is presented. this species, as many others of this ecosystem, has had few chemical and pharmacological studies. the simplest fraction with the largest activity against staphylococcus aureus (atcc 25923), is obtained starting from a raw ethanol extract and by means of bioassay guided partition. parallelly, phytochemical analyses to the portions of greater bioactivity, obtained during the whole process, are carried out. it is observed that antibacterial action increases as the chemical simplicity increases and that the presence of terpenes and flavonoids seems to be related with this action. this is the first report, so far well-known, of in vitro antibacterial activity for d. tolimense.
Distribución geográfica y clave de las especies del género oritrophium (kunth) cuatrec.(asteraceae) Geographical distribution and species key of the genus Oritrophium (Kunth) Cuatrec. (Asteraceae)
Anairamiz ARANGUREN B,Gilberto MORILLO,Mario FARI?AS
Acta Botánica Venezuelica , 2008,
Abstract: Oritrophium es un género de Asteraceae originario de monta as tropicales y subtropicales entre Bolivia y México. Se suministra una lista actualizada de las especies del género (21) y una clave. Se incluyen ilustraciones de 13 especies. Se realizó un análisis de agrupamiento con la distribución de especies por países. Las 21 especies conocidas se distribuyen entre 1500 y 5400 m snm. En conclusión el género presenta distribución disyunta entre Norteamérica y Sudamérica, con mayor cantidad de especies y endemismos en Ecuador, Perú y Venezuela. The genus Oritrophium (Asteraceae) is native of tropical and subtropical mountains from Bolivia to Mexico. An updated list and a species key are provided. Illustrations of 13 species are included. A cluster analysis of the distribution by countries of the genus is presented. The 21 currently known species of the genus are found between 1500 and 5400 m asl. As a conclusion Oritrophium has a disjunct distribution between North America and South America, with higher number of species and a higher endemism in Ecuador, Perú and Venezuela.
Distribución geográfica y clave de las especies del género oritrophium (kunth) cuatrec.(asteraceae)
ARANGUREN B,Anairamiz; MORILLO,Gilberto; FARI?AS,Mario;
Acta Botánica Venezuelica , 2008,
Abstract: the genus oritrophium (asteraceae) is native of tropical and subtropical mountains from bolivia to mexico. an updated list and a species key are provided. illustrations of 13 species are included. a cluster analysis of the distribution by countries of the genus is presented. the 21 currently known species of the genus are found between 1500 and 5400 m asl. as a conclusion oritrophium has a disjunct distribution between north america and south america, with higher number of species and a higher endemism in ecuador, perú and venezuela.
EFECTO DEL GRADIENTE ALTITUDINAL SOBRE ASPECTOS AUTOECOLóGICOS DE ESPELETIA PYCNOPHYLLA ssp. ANGELENSIS CUATREC. (ASTERACEAE) EN EL PáRAMO EL INFIERNILLO (NARI O-COLOMBIA) THE EFFECT OF THE ALTITUDINAL GRADIENT ON AUTOECOLOGICAL FEATURES OF ESPELETIA PYCNOPHYLLA ssp. ANGELENSIS CUATREC. (ASTERACEAE) IN THE PARAMO 'EL INFIERNILLO' (NARI O-COLOMBIA)
Iván F. Benavides-Martínez,Diana L. Burbano-Martínez,Sandra M. Urbano-Apráez,María E. Solarte-Cruz
Actualidades Biológicas , 2007,
Abstract: Se estudió el efecto de la elevación sobre algunos aspectos autoecológicos de la especie Espeletia pycnophylla ssp. angelensis Cuatrec. (Asteraceae), tales como su estructura demográfica, densidad poblacional, patrón de distribución espacial, producción de estructuras reproductivas, morfometría de adultos y supervivencia, en un páramo seco del departamento de Nari o (Colombia). Las hipótesis propuestas por otros autores acerca del efecto lineal que la elevación produce sobre estas variables, fueron completamente rechazadas. La elevación induce un efecto coenoclínico sobre la densidad poblacional y ésta a su vez, se correlaciona negativamente con la producción de estructuras reproductivas y el tama o de los adultos, evidenciándose un efecto inequívoco del fenómeno de la densodependencia sobre el potencial biótico de la población. En la zona intermedia del gradiente, la densidad poblacional es máxima, pero los tama os corporales son reducidos, la producción de estructuras reproductivas es mínima y la probabilidad de que un juvenil alcance edades avanzadas es baja. Evidentemente, esta elevación intermedia estaría presentando condiciones ecológicas favorables para el establecimiento y supervivencia de plántulas, lo que a largo plazo conlleva a un aumento de la densidad poblacional. Se propone que las generalizaciones de otros autores acerca de la influencia de la elevación sobre la autoecología de estas plantas son inverosímiles y limitadas, ya que la historia particular de vida y disturbio del páramo y los aislamientos espaciales, ecológicos y genéticos, son factores explicativos que no pueden aislarse del contexto. Paralelamente, la población se ajustó al modelo demográfico logarítmico, revelando su temprano estado de regeneración frente a la última quema ocurrida en el 2003, y la similitud de las curvas de supervivencia entre todas las elevaciones, probó una alta estabilidad demográfica. Some autoecological features of Espeletia pycnophylla ssp. angelensis Cuatrec. such as its demographic structure, population density, spatial pattern of dispersion, production of reproductive structures, adult morphometry and survivorship, were studied in an altitudinal gradient on a dry paramo of Nari o (Colombia). Hypothesis proposed by other authors about a linear effect caused by the elevation on these variables were completely rejected. The elevation induces an ecoclinal effect on population density, and this density correlates negatively with both production of reproductive structures and adult sizes. These results elucidate an unequivocal effect of density-dependen
EFECTO DEL GRADIENTE ALTITUDINAL SOBRE ASPECTOS AUTOECOLóGICOS DE ESPELETIA PYCNOPHYLLA ssp. ANGELENSIS CUATREC. (ASTERACEAE) EN EL PáRAMO EL INFIERNILLO (NARI?O-COLOMBIA)
Benavides-Martínez,Iván F.; Burbano-Martínez,Diana L.; Urbano-Apráez,Sandra M.; Solarte-Cruz,María E.;
Actualidades Biológicas , 2007,
Abstract: some autoecological features of espeletia pycnophylla ssp. angelensis cuatrec. such as its demographic structure, population density, spatial pattern of dispersion, production of reproductive structures, adult morphometry and survivorship, were studied in an altitudinal gradient on a dry paramo of nari?o (colombia). hypothesis proposed by other authors about a linear effect caused by the elevation on these variables were completely rejected. the elevation induces an ecoclinal effect on population density, and this density correlates negatively with both production of reproductive structures and adult sizes. these results elucidate an unequivocal effect of density-dependence phenomena on population fitness. the intermediate zone of the altitudinal gradient exhibits a high population density, but on the other hand show reduced corporal adult sizes, minimal production of reproductive structures and the probability of juveniles reaching advanced ages is low. evidently, this intermediate elevation can have favorable ecological conditions for the seedling establishment, wich increments population densities at long term. we propose that other author's generalizations about the influence of elevation on the autoecology of these plants are limited, because the particular life and disturbance stories of paramos and the spatial, ecological and genetic isolating are explicative factors impossible to take away from the context. the demographic structure of the population fitted the logarithmic model, revealing its early regeneration state from the last fire event on 2003 and the similarity of the survivorship curves among every elevation, probed a high demographic stability.
Análisis preliminar sobre anatomía del le?o de 11 especies de la tribu Heliantheae (Asteraceae) de Los Andes venezolanos
León H,Williams J;
Ernstia , 2007,
Abstract: the secondary xylem anatomy of eleven species of the heliantheae tribe (asteraceae) growing in the venezuelan andes is described. the species described are carramboa badilloi, c. littlei, c. pittieri, c. rodriguezii, c. tachirensis, c. trujillensis, libanothamnus granatesianus, l. neriifolius, l. occultus, montanoa quadrangularis and ruilopezia marcescens. m. quadrangularis is easy to separate from the others because it has septate fibres, exclusively simple perforation plates, pores with mean diameters greater than 100 mm and less than 20 pores/mm2. species from carramboa, libanothamnus and ruilopezia (espeletiinae subtribe) have remarkable similitude among them. the mean features to differentiate them are related with intervessel and ray-vessel pits. ruilopezia have wood anatomical features intermediate between carramboa and libanothamnus. we found sheath cells in c. littlei, c. pittieri, l. granatesianus and m. quadrangularis. the presence of growth rings was observed only in l. occultus. a dichotomous key for wood identification is included.
Análisis preliminar sobre anatomía del le o de 11 especies de la tribu Heliantheae (Asteraceae) de Los Andes venezolanos
Williams J León H
Ernstia , 2007,
Abstract: Se presenta la descripción anatómica del xilema secundario de once especies de la tribu Heliantheae de la familia Asteraceae procedentes de los Andes venezolanos (Mérida, Táchira). Las especies estudiadas son Carramboa badilloi, C. littlei, C. pittieri, C. rodriguezii, C. tachirensis, C. trujillensis, Libanothamnus granatesianus, L. neriifolius, L. occultus, Montanoa quadrangularis y Ruilopezia marcescens. M. quadragularis se diferencia del resto de las especies por la presencia de fibras septadas, platinas de perforación exclusivamente simples, poros con diámetro promedio mayor de 100 mm y menos de 20 poros/mm2. Las especies de Carramboa, Libanothamnus y Ruilopezia (subtribu Espeletiinae) guardan notables similitudes entre sí; las principales características para su diferenciación están relacionadas con las punteaduras intervasculares y radiovasculares. Ruilopezia presenta características que se pueden considerar como intermedias entre Carramboa y Libanothamnus. Se observaron células envolventes en C. littlei, C. pittieri, L. granatesianus y M. quadrangularis. La presencia de anillos de crecimiento sólo se evidenció en L. occultus. Se presenta una clave para la identificación de las once especies estudiadas. The secondary xylem anatomy of eleven species of the Heliantheae tribe (Asteraceae) growing in the Venezuelan Andes is described. The species described are Carramboa badilloi, C. littlei, C. pittieri, C. rodriguezii, C. tachirensis, C. trujillensis, Libanothamnus granatesianus, L. neriifolius, L. occultus, Montanoa quadrangularis and Ruilopezia marcescens. M. quadrangularis is easy to separate from the others because it has septate fibres, exclusively simple perforation plates, pores with mean diameters greater than 100 mm and less than 20 pores/mm2. Species from Carramboa, Libanothamnus and Ruilopezia (Espeletiinae subtribe) have remarkable similitude among them. The mean features to differentiate them are related with intervessel and ray-vessel pits. Ruilopezia have wood anatomical features intermediate between Carramboa and Libanothamnus. We found sheath cells in C. littlei, C. pittieri, L. granatesianus and M. quadrangularis. The presence of growth rings was observed only in L. occultus. A dichotomous key for wood identification is included.
Estructura primaria del sistema radical de Coespeletia Cuatrec.
Luque Arias,Rebeca;
Interciencia , 2004,
Abstract: the morphology and primary root structure of the species coespeletia cuatrec. that grow in the mountains of piedras blancas and sierra nevada, mérida, venezuela, are shown. the species are coespeletia alba, c. lutesecens, c. moritziana, c. spicata and c. timotensis. the presence of common characters such as monostratified epidermis that is rapidly replaced by the exodermis, presence of secretory cavities associated to the endodermis and the secretory nature of endodermis, were detected. differential characters were detected as well, such as cortex structure, number of primary xylem arcs, and number of cavities occurring opposite the phloem.
Antimicrobial activity of bergenin from Endopleura uchi (Huber) Cuatrec
Silva, Saulo L. da;Oliveira, Viviane Guedes de;Yano, Tomomasa;Nunomura, Rita de Cássia Saraiva;
Acta Amazonica , 2009, DOI: 10.1590/S0044-59672009000100019
Abstract: endopleura uchi (huber) cuatrec. is an amazon species traditionally used as treatment for inflammations and female disorders. bergenin was isolated from ethyl acetate fraction of bark of e. uchi by using column chromatography over sephadex lh-20 and then silica gel 60 flash. its structure was identified on the basis of its nmr spectra. the antimicrobial activity of bergenin and fractions of methanol extract of e. uchi were evaluated against atcc microorganisms (escherichia coli, salmonella enteritidis, pseudomonas aeruginosa, enterococcus faecalis, staphylococcus aureus, candida albicans, c. guilliermondii, aspergillus flavus, a. nidulans). clinically isolated strains of all of these microorganisms, along with c. tropicalis, a. niger, shigella sonnei, serratia marcenses and klebsiella pneumoniae were also evaluated. the growth inhibition caused by bergenin, extracts and fractions of e. uchi against atcc microorganisms were similar to the inhibition to microorganisms clinically isolated. the ethyl acetate fraction and the isolate bergenin inhibit the growth of the yeasts c. albicans, c. tropicalis, and c. guilliermondii, but present lower activity against filamentous fungi aspergillus flavus, a. nidulans, a. niger, and did not inhibit the gram positive and gram negative bacteria. the activity of the ethyl acetate fraction and bergenin are in agreement wit its high concentration found in bark extract of e. uchi. moreover, the selective activity against three candida species helps to understand its traditional use against infections that affect women.
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