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Gamme d'année
1.
Article | IMSEAR | ID: sea-200572

RÉSUMÉ

Background: Asthma is a chronic disease that affects approximately 300 million people worldwide. Tectona grandis Linn. bark, also known as Teak (English), is traditionally used to treat asthma. However, the scientific data on anti-asthmatic and anti-cholinergic of this plant has got little attention. An attempt has been based on ethanolic extract of bark of Tectona grandis Linn. shown a tremendous effect on asthma when comparative study was done with normal and treated group.Methods: The anti-asthmatic activity of a 95% ethanol and 5% distilled water extract of dried and fresh Tectona grandis Linn. bark, was evaluated against histamine and acetylcholine-induced preconvulsive dyspnea (PCD) in guinea pigs fasted for 24 h were exposed to an atomized fine mist of 2% histamine dihydrochloride and acetylcholine aerosol (dissolved in normal saline) using nebulizer at a pressure of 300 mmHg in the histamine chamber (24�� cm, made of perplex glass. They were divided in groups Mepyramin (8 mg/kg) intraperitonially, atropine aerosol and Tectona grandis bark formulation (2.5, 5, 10 gm/kg) were administered orally 30 min prior to exposure. Animals, which did not develop typical asthma within 6 minutes, were taken as protected.Results: Ethanolic extract of Tectona grandis Linn. bark at 5 and 10 gm/kg significantly reduce bronchoconstriction as compared to control group along with significant mast cell stabilization activity.Conclusions: In conclusion, the present study shows that the ethanolic bark extract of Tectona grandis Linn. has potential antiasthamatic and antichlolinergic action in histamine and acetylcholine broncocontraction in guinea pigs.

2.
European J Med Plants ; 2019 Nov; 29(4): 1-13
Article | IMSEAR | ID: sea-189508

RÉSUMÉ

Aim: Study aimed to evaluate the in vitro antisalmonellal and antioxidant properties of Tectona grandis, a medicinal plant commonly used in traditional Cameroonian medicine for the treatment of typhoid fever. Study Design: In vitro Antimicrobial and antioxidant analyses of plant extract using established protocols. Place and Duration of Study: Plant materiel collection at Loum (Moungo Division, Littoral region of Cameroon), identification at the National Herbarium of Cameroon, extraction of plant and all analyses at the Research Unit of Microbiology and Antimicrobial Substances, Department of Biochemistry, University of Dschang-Cameroon, between August 2018 and April 2019. Methodology: In vitro antisalmonellal activity of Tectona grandis extracts was evaluated by the liquid microdilution method as well as their antioxidant activity using by standard methods of H2O2 trapping, FRAP, DPPH radical trapping and OH radical trapping. Quantification test of total phenols and flavonoids and phytochemical screening of extract were also done. Results: The results showed that most of the Tectona grandis extracts had minimal inhibitory concentrations (MICs) ranging from 64 to 1024 μg/mL. Ethanolic extract, 70% ethanol extract and aqueous decoction are the most effective compared to aqueous extracts with activities between 64 and 128 μg/mL on the bacteria tested. Antioxidant tests showed that all extracts except macerated and aqueous infused extracts exhibited high DPPH trapping activities. The antioxidant activities of the extracts are proportionally linked in most cases to their flavonoid and total phenol contents at a concentration of 200 µg/mL. Aqueous decoction showed better H2O2 trapping activity at concentrations less than or equal to 25 µg/mL. Conclusion: These results show that the ethanolic extract and decocted aqueous of Tectona grandis leaves can be used as an alternative to treat salmonellosis.

3.
Article | IMSEAR | ID: sea-200730

RÉSUMÉ

The fatty acids in the oil of Garcinia kola, Tetracarpodium conopodiumand Tectona grandis were determined using a Perkin Elmer Auto sampler XL gas chromatograph with FID detector and split injector operating at 220ºC. The result showed that Garcina kolacontained saturated fatty acid (15.78%) monounsaturated fatty acid (33.29%) and polyunsaturated fatty acid (50.92%). Tetracarpodium conopodiumcontained saturated fatty acid (5.72%) monounsaturated fatty acid (77.31%) and polyunsaturated fatty acid (16.96%) tectona grandis contained saturated fatty acid (59.93%), monounsaturated fatty acid (24.08%) and polyunsaturated fatty acid 15.99%. The major fatty acid in Garcinia kolais oleic acid, while the major fatty acid in Tetracarpodium conopodumis paullinic acid and the major fatty acid in Tectona gradisis palmitic acid. In conclusion, the result of the fatty acid profile showed that Tetracarpodium conopodiumand Garcinia kolacontained high percentage of essential fatty acids while Tectona grandis also contained some essential fatty acids. Therefore the seeds oils may be useful in the food, beverages, fine chemical, oil and pharmaceutical industries

4.
Arq. Inst. Biol ; 86: e0232019, 2019. ilus
Article de Anglais | VETINDEX, LILACS | ID: biblio-1024605

RÉSUMÉ

Rust, caused by the biotrophic fungus Olivea neotectonae, stands out as an important disease in teak plantations in Brazil. Considering the current importance of this rust and the need to obtain additional basic information about its causal agent to better disease management, the present study aimed to analyze the morphology of O. neotectonae using light microscopy and demonstrate the infection process in teak leaves using scanning electron microscopy techniques (SEM). The morphological characteristics observed using light microscopy were similar to those described in the literature for this species. SEM revealed that the infection structures of the pathogen penetrated the teak leaf through the stomata complex. This study provides the first microscopic evidence of the infection process of Olivea neotectonae in leaves of teak plants.(AU)


A ferrugem, causada pelo fungo biotrófico Olivea neotectonae, destaca-se como uma doença importante nas plantações de teca no Brasil. Considerando a importância atual dessa ferrugem e a necessidade de obter informações básicas adicionais sobre seu agente causal para melhor manejo da doença, o presente estudo teve como objetivo analisar a morfologia da O. neotectonae utilizando microscopia de luz e demonstrar o processo de infecção em folhas de teca por meio de técnicas de microscopia eletrônica de varredura (MEV). As características morfológicas observadas em microscopia de luz foram semelhantes às descritas na literatura para essa espécie. A MEV revelou que as estruturas de infecção do patógeno penetraram na folha de teca através do complexo estomático. Este estudo fornece a primeira evidência microscópica do processo de infecção de Olivea neotectonae em folhas de plantas de teca.(AU)


Sujet(s)
Lutte contre les nuisibles , Forêt pluviale , Champignons , Maladies des plantes , Microscopie électronique/méthodes
5.
Acta amaz ; Acta amaz;47(3): 277-280, July-Sept. 2017. tab, graf
Article de Anglais | LILACS, VETINDEX | ID: biblio-1455342

RÉSUMÉ

Rust, caused by Olivea neotectonae, stands out as the main teak disease, causing premature defoliation regardless of the tree’s growth stage. In this study, we aimed to assess the temporal progress of rust in adult teak plants in southern Tocantins State (Brazil). Both rust incidence and severity were evaluated and the disease progress curves were obtained, adjusting to monomolecular, logistic and Gompertz mathematical models. Data from incidence and severity were correlated with climate variables collected by the agrometeorological station located in the study area. Rust incidence reached 100% at 98 days after beginning of the evaluations (DBE). The highest severity (equal or above 75%) was observed at 147 DBE. There was a significant and negative correlation between severity and minimum temperature. The adjustment of the Gompertz model suggests that control measures should be aimed primarily to reduce the rate of disease progress.


A ferrugem, causada por Olivea neotectonae, destaca-se como principal doença da teca, causando desfolha prematura em todos os estádios fenológicos da cultura. O objetivo do estudo foi avaliar o progresso temporal da ferrugem em plantas adultas de teca no sul do Estado do Tocantins. Avaliaram-se a incidência e severidade da ferrugem (escala de notas) e obtiveram-se curvas de progresso da doença, que foram ajustadas aos modelos matemáticos monomolecular, logístico e Gompertz. Correlacionaram-se os dados de incidência e severidade com as variáveis climáticas coletadas na estação meteorológica, localizada na região do estudo. A incidência da ferrugem atingiu 100% aos 98 dias a partir do início das avaliações (DIA). A maior severidade (igual ou acima de 75%) foi observada aos 147 DIA. Houve correlação negativa e significativa entre severidade e temperatura mínima. O ajuste ao modelo de Gompertz sugere que medidas de controle devem ser tomadas objetivando reduzir a taxa de progresso da doença.


Sujet(s)
Facteurs temps , Feuilles de plante , Champignons
6.
Article de Anglais | IMSEAR | ID: sea-169078

RÉSUMÉ

The timber value of Tectona grandis has been established from decades. Teak is an exotic species cultivated along most parts of tropical regions. Anthocyanins are natural colourants which have raised a growing demand due to their extensive range of colours, innocuous and beneficial health effects. Anthocyanins belong to large group of polyphenolics - flavonoids, which are secondary metabolites synthesized by higher plants. Despite the remarkable application of anthocyanins in food, pharmaceutical and cosmetic industries, still it is not properly exploited. In the present study, the bioactive components of Tectona grandis young leaves have been evaluated using Perkin-Elmer Gas chromatography-Mass spectrometry. GC-MS analysis revealed the existence of eleven compounds. 5,9-Methanobenzocycloocten-1(2H)-one,3,4,5,6,7,8,9,10-octahydro-5,10-dihydroxy-3,3,7,7,9- pentamethyl (76.02%) and 1-naphthalenecarboxylic acid,5-[2-(3-furanyl)ethyl]decahydro-1,4a-dimethyl-6- methylene-[1R-(1.alpha.,4a.)] (13.95%). Other compounds present in minor quantities were ledol(0.92%), 3- Buten-2-one,4-(2,6,6-trimethyl-1-cyclohexen-1-yl)orionone(0.49%),9,12,15 Octadecatrienoic acid, methyl ester, (Z,Z,Z)- or Linolenic acid methyl ester (0.82%), Phytol (0.69%), Cedran-diol, 8S,14- (0.60%), Lupeol (0.71%), 3- Methoxymethyl-2,5,5,8a-tetramethyl-6,7,8a-tetrahydro-5H-chromene (3.45%) and Retinol(1.27%). This is the first report of identification of active constituents from the young leaves of Tectona grandis.

7.
Ciênc. rural ; Ciênc. rural (Online);42(10): 1826-1832, out. 2012. ilus, tab
Article de Portugais | LILACS | ID: lil-651670

RÉSUMÉ

Tocos de árvores desbastadas de Tectona grandis apresentam rebrota intensa que compete com as árvores remanescentes. O objetivo deste trabalho foi avaliar a eficácia da aplicação isolada ou combinada de diferentes concentrações dos herbicidas picloram e triclopyr, associados ou não à aplicação de danos físicos, no controle dessas brotações. Em um povoamento com quatro anos de idade, os tocos foram tratados imediatamente após o desbaste. Em outro povoamento com seis anos, foram tratadas as brotações presentes nos tocos desbastados no ano anterior. Foi registrada a porcentagem de tocos mortos, o número de brotações por toco e as respectivas alturas. No primeiro ensaio, a aplicação combinada de picloram a 0,48% com triclopyr a 0,96%, associada a 20 rachas com machado matou todos os tocos. No segundo ensaio, a maior eficácia, 21,7%, foi registrada com roçada prévia das brotações e a aplicação de picloram a 0,96%. Após o desbaste, a aplicação isolada de picloram ou combinada com triclopyr associada ou não aos danos físicos é eficiente para controlar os brotos de teca. A aplicação nas rebrotas de tocos desbastados no ano anterior apresenta alguma eficiência, mas com menor percentual de tocos mortos em relação à aplicação após o desbaste.


The stumps of thinning trees of Tectona grandis L.f. present intense sprouts that compete with the remaining trees. The efficacy of the control of sprouts with the herbicides picloram and triclopyr, associated or no it applications of physical damages, were evaluated. Immediately after thinning, in plantation with four years old, the stumps were treated, and in other plantation, with age of six, the sprouts of stumps thinned in the previous year, were treated. The percentage of died stumps, the number of sprouts by stump and the respective heights were registered. In the first trial, the combined application of picloram at 0.48% with triclopyr at 0.96%, associated a 20 cracks with axe killed all stumps. In the second trial, the best efficacy, 21.7%, was obtained with the previous mowing of sprouts and application of picloram at 0.96%. After thinning, the isolated application of picloram or combined with triclopyr, associates or not a physical damage is efficient to control sprouts of teak. The application in the sprouts of stumps thinned in the last year present any efficiency, with least percentage of dead stumps in relation to application after thinning.

8.
Rev. biol. trop ; Rev. biol. trop;60(1): 483-494, Mar. 2012. ilus, graf, tab
Article de Anglais | LILACS | ID: lil-657795

RÉSUMÉ

Teak (Tectona grandis) is one of the most valuable timbers in international trade and an important species for tropical forestry. Teak is found on the island of East Timor but no information is available on teak growth from this region. A pure stand planted in 1940-50 in the North of East Timor and left unmanaged was studied. Fifteen trees were sampled in October-November 2003 and stem discs taken at three height levels of its height (1.7m, 9.5m and 18.7m), and cores were collected at DBH. Transverse surfaces of the discs and cores were polished for ring identification. Core cross sections were first digitized and disc cross sections were observed under the microscope. Three randomly selected radii were analyzed in each disc. Ring width measurement and ring counting were done using image analysis software. The distinction between heartwood and sapwood was performed macroscopically by colour difference, and heartwood radius and sapwood width were measured. The relationship between stem and heartwood radius was studied for each disc and heartwood percentage by radius was determined. Radial ring width curves are presented for the different axial positions within the stem, and ring width variability was analyzed. Growth rates were calculated and age-radius relationships were estimated using cumulative growth curves. Growth rings were large and well defined in the juvenile phase, reflecting the specie’s fast-growing character. The year-to-year variation of ring width showed a similar pattern among trees. Mean ring width ranged between 4.3-7.3mm for the first 20 years and 3.3-5.1mm for 30 to 45 years. Pith eccentricity was evident in the lower part of the stem and ring wedging occurred. On average, heartwood represented 84% of the radius and sapwood contained 6 to 11 rings. The age-related variation of ring width and the occurrence in the lower part of the tree stems of eccentricity and wedging rings, highlights the importance of appropriate stand management, particularly regarding basal density distribution over time, whenever optimized timber production is envisaged.


La madera de teca (Tectona grandis L.f.) es una de las más valiosas en el comercio internacional y una especie importante para la silvicultura tropical. La teca se encuentra en la isla de Timor Leste, pero no existe información disponible sobre su crecimiento en esta región. Se estudió una plantación pura no manejada que fue establecida entre 1940 y 1950 en el Norte de Timor Leste. Entre Octubre- Noviembre 2003 se cosecharon 15 árboles y al tronco se les extrajeron discos a tres niveles de altura (1.7m, 9.5m y 18.7 m), y se recolectaron núcleos a la altura del pecho (DAP). El conteo y la medición de los anillos se realizaron mediante el software de análisis de imagen. La distinción entre el duramen y la albura se realizó macroscópicamente por la diferencia de color, y se midieron el radio del duramen y el ancho de la albura. Para cada disco se estudió la relación entre el tallo y radio del duramen y el porcentaje del duramen. Las curvas de variación del ancho de los anillos se presentan para las diferentes posiciones axiales dentro del tronco y se analizó la variabilidad del ancho de los anillos. Las tasas de crecimiento fueron calculadas y las relaciones de radio con la edad se calcularon usando las curvas de crecimiento acumulado. Los anillos de crecimiento eran grandes y bien definidos en la fase juvenil, lo que refleja el carácter de crecimiento rápido de esta especie. La variación en la anchura de los anillos año a año mostró un patrón similar entre los árboles. La anchura media del anillo osciló entre 4.3-7.3mm para los primeros 20 años y 3.3-5.1mm para los de 30 a 45 años. La excentricidad de la médula fue evidente en la parte inferior del tallo y se observó la formación de anillos sobrepuestos. En promedio, el duramen representó el 84% del radio y la albura mostró entre 6 y 11 anillos. La variación del ancho de los anillos con la edad, la presencia de excentricidad en la parte inferior del árbol y los anillos sobrepuestos pone de relieve la importancia del manejo forestal con particular atención a la distribución de densidad basal en el tiempo, cuando se pretende la producción optimizada de la madera.


Sujet(s)
Arbres , Verbenaceae/croissance et développement , Timor oriental , Verbenaceae/classification
9.
Ciênc. rural ; Ciênc. rural (Online);41(12): 2101-2107, Dec. 2011. ilus
Article de Portugais | LILACS | ID: lil-608077

RÉSUMÉ

Este estudo objetivou verificar a ocorrência de insetos em reflorestamentos experimentais com paricá, Schizolobium parahyba var. amazonicum (Fabaceae); acácia, Racosperma mangium (Fabaceae) e teca, Tectona grandis (Lamiaceae), na região de Pau d'Arco, PA, associando os efeitos sazonais e ontogenéticos nos plantios. O estudo foi conduzido entre os meses de maio de 2006 a junho de 2007 e constou de levantamentos mensais de insetos associados a plantios com idades de três a 16 meses. Houve associação positiva entre a ocorrência de insetos e suas respectivas injúrias com a sazonalidade e o desenvolvimento das plantas. Ao menos um pico populacional de insetos desfolhadores, sugadores e/ou polinizadores foi observado nas três espécies florestais. A análise de agrupamento confirmou a associação entre ocorrência de insetos, período chuvoso e idade da planta, destacando-se (a) lepidópteros em T. grandis, (b) coleópteros desfolhadores em S. parahyba; (c) acridídeos e lepidópteros em R. mangium; (d) cicadelídeos em S. parahyba e T. grandis; e (e) apídeos em R. mangium.


This study aimed to verify the occurrence of insects in experimental reforestation with Schizolobium parahyba var. amazonicum (Fabaceae) known as paricá, Racosperma mangium (Fabaceae) known as acacia and Tectona grandis (Lamiaceae) known as teca in the region of Pau d'Arco, Pará State, Brazil associating the seasonal and ontogenetic effects in plantations. The study was conducted from May 2006 to June 2007 and consisted of monthly surveys of insects associated with plantations aging 3 to 16 months. There was a positive association between the occurrence of insects and their injuries with seasonality and plant development. At least one population peak of defoliators, sucking and / or pollinators were observed in three tree species. Cluster analysis confirmed the association between the occurrence of insects, rainy season and plant age, especially (a) lepidopteran in T. grandis, (b) defoliators beetles in S. parahyba, (c) acridids and lepidopteran in R. mangium (d) cicadellids in S. parahyba and T. grandis, and (e) apids in R. mangium.

10.
Rev. bras. farmacogn ; 16(3): 392-396, jul.-set. 2006. ilus, tab
Article de Portugais | LILACS | ID: lil-571007

RÉSUMÉ

O fracionamento do extrato hexânico do caule de um espécime de reflorestamento de Tectona grandis (Verbenaceae), através de procedimentos fitoquímicos clássicos, levou ao isolamento das naftoquinonas lapachol e desidro-a-lapachona e das antraquinonas tectoquinona e obtusifolina. As estruturas das substâncias foram caracterizadas através da análise de métodos espectrométricos de RMN. Este é o primeiro estudo fitoquímico de um espécime de reflorestamento de Tectona grandis, no Brasil, sendo o objetivo principal deste trabalho a comprovação da presença de tectoquinona em espécimes cultivados.


The hexane extract of the bark of Tectona grandis (Verbenaceae) afforded two anthraquinones and two naphtoquinones. Their caracterizations were obtained through NMR spectroscopic techniques. This is the first phytochemical study of the bark of Tectona grandis reforestation specimen in Brazil. The main interest in this work is proving the presence of tectoquinone in reforestation specimen.

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