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In vitro antimalarial activity of fractions and constituents isolated from Tabebuia billbergii
Gómez-Estrada,Harold; Gaitán-Ibarra,Ricardo; Díaz-Castillo,Fredyc; Pérez,Hilda A; Medina,José D;
Revista Cubana de Plantas Medicinales , 2012,
Abstract: introduction: in vitro antimalarial activity of naphthoquinones (1-5), isolated from tabebuia billbergii (bureau & k. schum.) standl., was investigated. tabebuia billbergii, commonly known as guayacán, is a plant traditionally used in the amazon in numerous conditions like bacterial and fungal infections, fever, syphilis, malaria, trypanosomiasis, as well as stomach and bladder disorders, and tumours. objective: to study the dichloromethane extracts of both the trunk and the inner bark of tabebuia billbergii and to demonstrate the antimalarial activity of some of its bioactive components. methods: some bioactive components were evaluated for the antimalarial activity against plasmodium berghei, by using the inhibition of the differentiation cycle of the parasite measure by the 3h-hypoxanthine incorporation and compared to that obtained for chloroquine. results: conventional chromatographic techniques and bioassay-guided fractionation (artemia salina) allowed isolating from the active fractions one naphthoquinone (lapachol) and four naphtho-furan-4,9-diones. these compounds proved to have an important antiplasmodial effect, with very encouraging ic50's, especially when compared to the results shown by chloroquine in the same experiment. in addition, two triterpenes, β-sitosterol and stigmasterol, were obtained from the bark. conclusions: the activity-guided fractionation (a. salina) of dichloromethane extracts of the trunk and the inner bark of tabebuia billbergii led to the isolation and the identification of five quinonoid compounds with antiplasmodial effect. the significant inhibitory activity in vitro against plasmodium berghei observed for compound 2-acetyl-naphtho-[2,3b]-furan-4,9-dione allow us to present them as a potential antimalarial compound.
Actividad antiinflamatoria, antioxidante y antibacteriana de dos especies del género Tabebuia Antiinflammatory, antioxidant and antibacterial activity of two species of Tabebuia genus
Luis Alberto Franco Ospina,Jenny Paola Castro Guerrero,Yanet Cecilia Ocampo Buendía,Indira Beatriz Pájaro Bolívar
Revista Cubana de Plantas Medicinales , 2013,
Abstract: Introducción: Tabebuia rosea (Bertol.) A. DC. y Tabebuia ochracea (Cham.) Standl., que pertenecen a la familia Bignoniaceae, son utilizadas en la medicina popular por su potencial farmacológico como antiinflamatorio y antibacteriano, lo que ha motivado su estudio químico y biológico. Objetivos: determinar la actividad antiinflamatoria, antioxidante y antibacteriana de extractos totales etanólicos y fracciones en éter, diclorometano, acetato de etilo y etanol, obtenidas a partir de la corteza interna de Tabebuia rosea y Tabebuia ochracea. Métodos: el material vegetal se extrajo por maceración con etanol y se fraccionó mediante procedimientos de partición líquido/líquido. La actividad antiinflamatoria se evaluó utilizando el modelo murino in vivo de edema auricular inducido por 13-acetato de 12-orto-tetradecanoilforbol, mientras que la actividad antioxidante y antibacteriana se determinó in vitro, utilizando el método de captación del radical 2,2-difenil-1-picrilhidrazilo y métodos de difusión en agar, respectivamente.Resultados: los extractos etanólicos de la corteza de Tabebuia rosea y Tabebuia ochracea, así como algunas de sus fracciones, mostraron significativa actividad antiinflamatoria y antioxidante; en términos generales Tabebuia rosea resultó más activa como antiinflamatoria, mientras que en cuanto a la actividad antioxidante Tabebuia ochracea mostró ser más potente. Ambas especies de Tabebuia presentaron importante actividad antibacteriana frente a Staphylococcus aureus ATCC25923. Conclusiones: se demostró actividad antiinflamatoria, captadora de radicales libres 2,2-difenil-1-picrilhidrazilo y antibacteriana, en extractos totales y fracciones obtenidas de Tabebuia rosea y Tabebuia ochracea. Este constituye el primer reporte que valida el uso popular dado a estas especies como antiinflamatorio y antibacteriano, en la costa norte colombiana. Introduction: Tabebuia rosea (Bertol.) A. DC. and Tabebuia ochracea (Cham.) Standl., belonging to the Bignoniaceae family, are widely used in folk medicine because of their antiinflammatory and antibacterial potentialities, all of which has prompted the chemical and biological study of these species. Objectives: to evaluate the antiinflammatory, antioxidant and antibacterial activity of the total ethanolic extracts and fractions obtained from the inner bark of Tabebuia rosea and Tabebuia ochracea by using ether, dichloromethane, ethyl acetate and ethanol. Methods: plant material was extracted through maceration with ethanol and fractionated through liquid-liquid partition method. The evaluation of antiinflamma
Anatomia foliar de Tabebuia serratifolia (Vahl) Nich. (Bignoniaceae) propagadas in vitro, in vivo e durante a aclimatiza??o
Dousseau, Sara;Alvarenga, Amauri Alves de;Castro, Evaristo Mauro de;Soares, Roberta Pereira;Emrich, Eduardo Bucsan;Melo, Lucas Amaral de;
Ciência e Agrotecnologia , 2008, DOI: 10.1590/S1413-70542008000600002
Abstract: the seedlings spread by micropropagation techniques, usually show significant alterations induced by the conditions in vitro, which decrease the survival capacity after the transfer to conditions ex vitro. the evaluation of the structural change during the acclimatization is necessary for the understanding of this adaptation process. the objective of this research was to identify the anatomical differences among the seedlings cultivated in vitro, in vivo and acclimatized plants of tabebuia serratifolia (vahl) nich. (yellow ipe), species with great medicinal and ornamental interest. one used seedlings maintained for 43 days in growth chamber, with 20, 40, 60 and 80 days of acclimatization and seedlings after 90 days of cultivation in vivo. seedlings were obtained from culture of embryos in half bad and transplanted to tubes containing plantmax?, for aclimatiza??o in nursery house under 50% of shad. in the same conditions of the acclimatization the seedlings in vivo were produced. transversal and paradermal sections were prepared using the usual microthecniques. the results showed that the seedlings in vitro have the leaf tissue little differed and the stomata are open and bigger, demanding greater cares in the initial stage of acclimatization. at 60 days of acclimatization the new leaves produced have some anatomical aspects that can originate higher photosynthetic efficiency and better water regulation capacity of the plants.
Propagación in vitro de material seleccionado de Tabebuia rosea (Bertol.) DC. (Ocobo) y Cordia alliodora (Ruiz & Pav.) Oken (Nogal Cafetero)* Propagación in vitro de material seleccionado de Tabebuia rosea (Bertol.) DC. (Ocobo) y Cordia alliodora (Ruiz & Pav.) Oken (Nogal Cafetero)*
Schuler G. Ingrid,Sonrise Baquero O.,Hodson de Jaramillo Elizabeth
Revista Colombiana de Biotecnología , 2005,
Abstract: This work was aimed at multiplying and maintaining in vitro plants from seedlings from five Tabebuia rosea (large spreading cedar tree) from and one Cordia alliodora (walnut tree used for providing shade for coffee plantations). Apical leaf buds were excised from mother plants (MP) and cultured in vitro until 1480 plants had been produced from the two species. The hardening process was carried out in greenhouse conditions using humid flow-chambers at Geoambiente Ltda's Bambusa experimental station in Pacho, Cundinamarca. A database was created using Microsoft Office Access software for handling information required for monitoring and evaluating each plant's behaviour during the in vitro culture process by calculating the rates of multiplication (RM) and loss (RL). The plants so produced will be used by Conif for field trials and evaluation purposes. This material will then be multiplied by vegetative propagation and used for clone and molecular testing analysis. Key words: in vitro collection and propagation, Tabebuia rosea, Cordia alliodora. El presente trabajo tuvo por objetivo multiplicar y mantener in vitro plantas de Tabebuia rosea y de Cordia alliodora, a partir de semillas de cinco árboles plus de la primera especie y uno de la segunda. A partir de este material se seleccionaron plantas núcleo (PN), Yemas apicales de las plantas núcleo obtenidas, fueron removidas y cultivadas bajo condiciones in vitro hasta producir 1480 plantas de las dos especies. El proceso de aclimatización del material vegetal se llevó a cabo bajo condiciones de invernadero, en cámaras húmedas ubicadas en la estación experimental "Bambusa" en Pacho, Cundinamarca. Para el manejo de la información, se dise ó una base de datos en el programa Access, Microsoft Office , con el fin de monitorear y evaluar el comportamiento de cada uno de los individuos durante el desarrollo in vitro, por medio del cálculo de tasas de velocidad de multiplicación (TVM), tasa de pérdida (TP) y tasa de eficiencia del proceso (TE). Este material será entregado a Conif para el establecimiento de la primera plantación de origen in vitro, que será utilizada posteriormente para ensayos de propagación vegetativa, análisis de pruebas clonales y moleculares. Palabras clave: Micropropagación y colección in vitro, Tabebuia rosea, Cordia alliodora.
GERMINATION IN VITRO AND E EX VITRO OF EMBRYOS/SEEDS OF Tabebuia serratifolia (VAHL) NICH
Marcela Carlota Nery,Maria Laene Moreira de Carvalho,Luciana Magda de Oliveira,Fernanda Carlota Nery
CERNE , 2008,
Abstract: The knowledge of germination of seeds allows understanding the behavior of seeds during development and theconservation mechanism. For evaluating the germination of the seeds of ipê amarelo collected during seven development stages, 10,18, 25 32, 39, 47 and 53 days after the anthesis, the medium of culture in vitro were tested, MS and WPM, and methods ofdisinfestations of the seeds in the germination ex vitro. Seeds of yellow ipê disinfestations with carbendazim (2% for 2 minutes), sodiumhypochlorite (2% of the active chlorine for 3 minutes) and seeds without surface sterilisation, were submitted to the germination teston sand to 30 oC, under constant white light. In the cultivation in vitro, seeds acquired germinative capacity 39 days after the anthesisand superior germination 53 days after the anthesis, independent of the medium of culture. In the germination ex vitro, the seedsdisinfestations with carbendazim and without surface sterilization presented superior germination, the use of sodium hypochloritecaused fitotoxin effect to the seeds.
Anatomia foliar de ipê-branco (Tabebuia roseo alba (Ridl.) Sand.) – Bignoniaceae, proveniente do cultivo ex vitro e in vitro = Ex vitro and in vitro leaf anatomy of Tabebuia roseo alba (Ridl.) Sand. – Bignoniaceae
Leticia Caravita Abbade,Patrícia Duarte de Oliveira Paiva,Renato Paiva,Evaristo Mauro de Castro
Acta Scientiarum : Biological Sciences , 2009,
Abstract: Este estudo teve como objetivo comparar a estrutura interna de folhas de ipêbranco cultivadas in vitro e ex vitro. Para as avalia es anat micas foram utilizadas folhas do primeiro nó de ramos, da base para o ápice, com 30 dias de cultivo in vitro e de plantas de campo. O estudo anat mico foi feito por meio das sec es transversais e paradérmicas das folhas. As folhas apresentam epiderme uniestratificada e mesofilo dorsiventral. S o hipostomáticas e apresentam tricomas em todas as faces. Folhas de plantas cultivadas ex vitro, quando comparadas com in vitro, tiveram espessura do limbo foliar, nervura central da epiderme adaxial e abaxial e os parênquimas pali ádico e esponjoso maiores. Em folhas oriundas do cultivo in vitro, a cutícula e o esclerênquima s o ausentes. Folhas de plantas cultivadas ex vitro apresentaram menor número de est matos e maior número de tricomas, quando comparadas com o cultivo in vitro. Os est matos de folhas cultivadas in vitro s o maiores que os de folhas ex vitro. Considering the importance of knowledge of anatomical structures in the protocol definition for the micropropagation of the ipê-branco, this study compared the in vitro and ex vitro internal structure of leaves. For anatomical evaluations, the first leaf in vitro with 30 days of growth and adult plants were used. The anatomical study of leaves was based on microscope examination from cross-sectional and paradermic sections from the leaf blade. The leaf structures from plants ex vitro show uniseriate skin, and mesophyll with dorsiventral organization. They are hipostomatics and trichome is present in all faces. Leaves ex vitro was thicker that culture in vitro in limb, central nervure, epidermis and palisade and spongious parenchyma. In leaves in vitro, cuticle and sclerenchyma are absent. Leaves of ex vitro presented minor numbers of stomata and greater number of trichromes when compared with culture in vitro. Stomata of in vitro are larger than stomata ex vitro.
Capacidad antioxidante in vitro de fracciones de hojas de Piper peltatum L. In vitro antioxidant capacity of fractions from Piper peltatum L. leaves
Miguel A Puertas-Mejía,Luisa Gómez-Chabala,Benjamín Rojano,Jairo A Sáez-Vega
Revista Cubana de Plantas Medicinales , 2009,
Abstract: INTRODUCCIóN: el estudio de plantas medicinales se ha venido realizando desde hace décadas, por causa de su uso potencial como fuente de sustancias con propiedades biológicas. Piper peltatum L. ha presentado un sinnúmero de aplicaciones médicas, por lo que surge la necesidad de indagar su eventual capacidad antioxidante. OBJETIVO: evaluar la actividad antioxidante de extractos no alcohólicos obtenidos de las hojas de P. peltatum. MéTODOS: hojas secas y pulverizadas fueron sometidas a cromatografía en columna y 3 fracciones fueron obtenidas. El potencial antioxidante se determinó sobre la base de la capacidad reductora medida por el ensayo de FRAP (ferric reducing ability of plasma) y de la capacidad de atrapamiento del radical estable 2-2-difenil-1-picrilhidrazilo (DPPH, 2-2-diphenyl-1-picrylhydrazyl). RESULTADOS: aunque todas las muestras evaluadas mostraron buena capacidad antioxidante frente a los métodos aplicados, la identificada como fracción 1 fue la más promisoria, inclusive más eficiente que el ácido ascórbico (inhibición radical DPPH: 75 y 68 %, respectivamente). CONCLUSIONES: los datos presentados en este estudio demostraron que todas las muestras evaluadas poseen propiedades antioxidantes, lo cual soporta el uso tradicional de P. peltatum para el tratamiento de diferentes afecciones de la piel y otras enfermedades. INTRODUCTION: medicinal plants have been studied for decades because of their potential use as sources of substances with biological properties. Piper peltatum L. has many medical applications, hence the need of ascertaining its eventual antioxidant capacity. OBJECTIVE: to evaluate the antioxidant action of non-alcoholic extracts from P.peltatum leaves. METHODS: dry powered leaves were subjected to column chromatography, thus obtaining three fractions. The antioxidant potential was determined based on the reducing capacity as measured by FRAP assay (ferric reducing ability of plasma) and the trapping capacity of stable radical 2-2-diphenyl-1-picrylhydrazyl (DPPH assay). RESULTS: although all the evaluated samples showed good antioxidant capacity in comparison to the applied methods, fraction #1 was the most promising, being more efficient than ascorbic acid (radical DDPH inhibition; 75 and 68 % respectively). CONCLUSIONS: the data provided in this study proved that all the evaluated samples had antioxidant properties, all of which endorses the traditional use of P. peltatum for treatment of several skin diseases and other kind of ailments.
EVALUACIóN DE LAS PROPIEDADES ANTIOFíDICAS DEL EXTRACTO ETANóLICO Y FRACCIONES OBTENIDAS DE Renealmia alpinia (Rottb) Mass (Zingiberaceae) CULTIVADA IN VITRO ANTIOPHIDIAN PROPERTIES EVALUATION OF ETHANOL EXTRACT AND FRACTIONS OBTAINED FROM Renealmia alpinia (Rottb) Mass (Zingiberaceae)CULTIVATED IN VITRO  [cached]
Maritza FERNáNDEZ C,William F ORTIZ C,Jaime A PEREá?EZ J,Diego MARTíNEZ R
Vitae , 2010,
Abstract: Los extractos vegetales constituyen una fuente rica de moléculas farmacológicamente activas, cuya aplicación en medicina tradicional permite un acercamiento a potenciales actividades biológicas. En este trabajo se evalúa la capacidad inhibitoria de extractos etanólicos de hojas, raicillas y fracciones obtenidas por cromatografía en columna de Renealmia alpinia (Rottb) Mass, cultivada in vitro, sobre los efectos hemolítico indirecto, proteolítico y coagulante inducidos por el veneno de Bothrops asper. La actividad hemolítica indirecta es inhibida en mayor medida por la fracción 7-8 (47,3 ± 2,20%), seguida en su orden por los extractos de raicillas (32,6 #177; 6,90%) y hojas (24,2 ± 4,43%) de origen in vitro y hojas ex vitro (16,2 ± 3,88%). La actividad proteolítica se inhibe ampliamente por los extractos de hojas tanto in vitro como ex vitro sin diferencias significativas. Contra la actividad coagulante se registra una mayor neutralización por parte de las raicillas in vitro (81,73 ± 9,94s). Se descarta un potencial mecanismo de acción proteolítico de Renealmia alpinia sobre el veneno de Bothrops asper dado que no se producen cambios en los patrones electroforéticos del veneno. Los resultados viabilizan la aplicación de Renealmia alpinia como coadyuvante en el tratamiento del accidente ofídico y sustentan la utilidad de la micropropagación para la producción masiva de componentes activos. Plant extracts are a rich source of pharmacologically active molecules. Their application allows a tradicional medicine approach to potential biological acitivities. This paper evaluates the inhibitory capacity of ethanolic extracts of leaves and little roots and also fractions chromatographically fractions obtained from Renealmia alpinia (Rottb) Mass, cultured in vitro, on the indirect hemolytic activity, proteolytic activity and coagulant activity induced by the Bothrops asper venom. Indirect hemolytic activity is inhibited to a greater extent by the fraction 7-8 (47.3 ± 2.20%) followed in order by the extracts from little roots (32.6 ± 6.90%) and leaves (24.2 ± 4.43%). They came from in vitro and ex vitro leaves (16.2 ± 3.88%). The proteolytic activity is largely inhibited by the leaves extracts in vitro and ex vitro without significant differences between them. Little roots in vitro showed the highest neutralization effect on coagulant activity (81.73 ± 9.949s). Proteolytic activity from Renealmia alpinia extracts on Bothrops asper venom is ruled out since there are not changes in the electrophoretic pattern of the venom. The results make possible the implementation
EVALUACIóN DE LAS PROPIEDADES ANTIOFíDICAS DEL EXTRACTO ETANóLICO Y FRACCIONES OBTENIDAS DE Renealmia alpinia (Rottb) Mass (Zingiberaceae) CULTIVADA IN VITRO
FERNáNDEZ C,Maritza; ORTIZ C,William F; PEREá?EZ J,Jaime A; MARTíNEZ R,Diego;
Vitae , 2010,
Abstract: plant extracts are a rich source of pharmacologically active molecules. their application allows a tradicional medicine approach to potential biological acitivities. this paper evaluates the inhibitory capacity of ethanolic extracts of leaves and little roots and also fractions chromatographically fractions obtained from renealmia alpinia (rottb) mass, cultured in vitro, on the indirect hemolytic activity, proteolytic activity and coagulant activity induced by the bothrops asper venom. indirect hemolytic activity is inhibited to a greater extent by the fraction 7-8 (47.3 ± 2.20%) followed in order by the extracts from little roots (32.6 ± 6.90%) and leaves (24.2 ± 4.43%). they came from in vitro and ex vitro leaves (16.2 ± 3.88%). the proteolytic activity is largely inhibited by the leaves extracts in vitro and ex vitro without significant differences between them. little roots in vitro showed the highest neutralization effect on coagulant activity (81.73 ± 9.949s). proteolytic activity from renealmia alpinia extracts on bothrops asper venom is ruled out since there are not changes in the electrophoretic pattern of the venom. the results make possible the implementation of renealmia alpinia as adjuvant for the treatment of ophidic accidents and sustain the value of micropropagation for mass production of active components.
DESCOMPOSICIóN EN FRACCIONES PARCIALES  [cached]
ALEJANDRO MARTíNEZ A.
Scientia Et Technica , 2006,
Abstract: En este artículo se estudia el método de Heaviside para descomponer una fracción propia f (x) = p(x) / q(x) , es decir, p y q son polinomios, y grado( p(x)) < grado(q(x)) . Este tipo de descomposición se utiliza en el cálculo de integrales de funciones racionales y para encontrar algunas transformadas inversas de Laplace y se basa en un teorema del álgebra avanzada, el cual establece que cada función racional, sin importar que tan complicada sea, puede rescribirse como una suma de fracciones más simples.
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