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Germina o de sementes de Asteraceae nativas no Rio Grande do Sul, Brasil  [cached]
Ferreira Alfredo Gui,Cassol Bibiana,Rosa Shirley Galli Taylor da,Silveira Tania Sales da
Acta Botanica Brasilica , 2001,
Abstract: Aquênios (sementes) recém coletados, de treze espécies nativas de Asteraceae comuns nos ambientes abertos da regi o sul do Brasil foram testados quanto à germina o em temperaturas alternadas ( 20/10; 25/15; 30/20; 35/25°C) e sob temperaturas constantes ( 20; 25 e 30°C) com ou sem luz. A temperatura ótima para germina o varia entre as espécies, sendo que as espécies Elephantopus mobilis; Eupatorium laevigatum; Mikania cordifolia; Senecio oxyphyllus; Trixis prastens germinam de forma semelhante em todas temperaturas testadas. Eclipta alba tem sua germina o promovida a 30°C. Tagetes minuta tem a germina o das sementes promovida a 20°C. Em Senecio heterotrichius; S. selloi; Stenachaenium campestre; Symphyopappus casarettoi e Vernonia nudiflora as sementes germinam igualmente a 20 ou 25°C.. A luz promoveu a germina o de todas espécies exceto para Stenachaenium campestre e Tagetes minuta, sendo esta última espécie fotoblástica negativa. Quanto ao tempo médio de germina o, as espécies podem ser divididas em ; rápidas- menos de 5 dias (Baccharis trimera; Eclipta alba; Elephantopus mollis; Stenachaenium campestre e Vernonia nudiflora); intermediárias: entre 5 e 10 dias ( Eupatorium laevigatum; Mikania cordifolia e Tagetes minuta) ; lentas: mais de 10 dias (Senecio heterotrichius; S.oxyphyllus; S.selloi; Symphyopappus casarettoi e Trixis praestans).Os resultados mostram que a germina o de sementes de Asteraceas variam com a temperatura e o regime de luz; podendo prover uma base inicial para interpreta o de efeitos sazonais sobre a germina o e estabelecimento a campo. Em adi o, comentários sobre o substrato ágar ou areia s o feitos.
Eupatorium guiengolense (Asteraceae: Eupatorieae), una nueva especie de Oaxaca, México  [cached]
Leticia Torres Colín,José Luis Villase?or
Acta botánica mexicana , 1993,
Abstract: Colectas intensivas en el Distrito de Tehuantepec, Oaxaca, llevadas a cabo por el Herbario Nacional, dieron como resultado el descubrimiento de una especie nueva de Eupatorium. Esta especie nueva es descrita e ilustrada; se discuten sus afinidades con E. ovaliflorum y se proporciona una clave para su diferenciación.
Composi??o química volátil e n?o-volátil de Eupatorium ballotifolium Kunth, Asteraceae
Albuquerque, Maria Rose Jane R.;Santos, Hélcio S. dos;Souza, Elnatan B. de;Silva, Rochanne M. da;Menezes, Jane Eire Silva A. de;Pessoa, Otília Deusdênia L.;Braz-Filho, Raimundo;Costa, S?nia Maria O.;
Revista Brasileira de Farmacognosia , 2010, DOI: 10.1590/S0102-695X2010000400023
Abstract: this work describes the chemical composition of the essential oils and the isolation of eleven substances from eupatorium ballotifolium kunth, asteraceae. the essential oils were obtained by hydrodistillation, analyzed by gc/ms and evaluated towards the acetylcholinesterase enzyme. the oils yield was of 0.11% for the leaves and 0.03% for the stems. the main constituents of the oils were the sesquiterpenes β-caryophyllene (24.9 and 22.2%), spathulenol (17.7 and 12.4%) and epoxy-allo-aromadendrene (23.0 and 23.6%). from the hexane extract of the aerial part were isolated a mixture of sitosterol and stigmasterol, its glucosides, and the triterpenes taraxasteryl acetate and taraxasterol, while from the ethanol extract were obtained the flavonoids nepetin and 3-o-glucoside-quercetin. the triterpenes epi-friedelanol and dammara-20,24-dien-3β-ol were obtained from the hexane extract of roots, while the coumarin 11-hydroxy-11,12-di-hydroobliquine was obtained from the ethanol extract. the structures of all compounds were determinate based on spectroscopic methods such as ir, ms and 1h and 13c nmr
Evaluación del efecto tóxico de extractos de Eupatorium microphyllum L.F. (Asteraceae) sobre larvas de Aedes aegypti (Diptera: Culicidae) en condiciones de laboratorio
Rozo,álvaro; Zapata,Cristina; Bello,Felio J.;
Revista Ciencias de la Salud , 2008,
Abstract: in the present work the toxic activity of extracts of eupatorium microphyllum l.f. was evaluated on 4 th instar larvae of the mosquito aedes aegypti (linneaus), under laboratory conditions. aqueous extracts were utilized in concentrations of 500 mg l-1, 1,500 mg l-1 and 2,500 mg l-1 and acetone in concentrations of 10 mg l-1, 20 mg l-1, 30 mg l-1, 40 mg l-1 and 50 mg l-1. the bioassays were carried out for triplicate each one with 20 larvae, exposed for 24 hours to 150 ml of solution. in all the bioassays were employed control groups. in the evaluation of the acetone extracts, a negative control was employed to avoid that the mortality of the larvae to occur on account of the solvent. the aqueous extracts showed low moderate action in the mortality of larvae, less than 20%. on the contrary, the action of the acetone extracts was observed to 10 and 20 mg l-1 with 15% of mortality, while to 30 and 40 mg l-1 were registered 22 to 38% of mortality. however, to 50 mg l-1 the mortality was of 95.4% with highly significant statistical results. the concentrations of the acetone extracts showed to be the most efficient for the control of the mosquitoes selected. both types of extracts showed toxic effect in larvae of a. aegypti, nevertheless, greater effect in the acetone extracts was observed relating to the aqueous extracts of e. microphyllum, which constitutes a viable alternative in the search of new larvicides from composed natural.
Fenologia de quatro espécies tóxicas de Senecio (Asteraceae) na regi o Sul do Rio Grande do Sul
Karam Fernando Sérgio Castilhos,Carmen Méndez Maria del,Jarenkow Jo?o André,Riet-Correa Franklin
Pesquisa Veterinária Brasileira , 2002,
Abstract: O objetivo principal desse trabalho foi determinar a fenologia de Senecio brasiliensis, S. oxyphyllus, S. heterotrichius e S. selloi, e relacioná-la com a epidemiologia da intoxica o em bovinos, na regi o sul do Rio Grande do Sul. O estudo fenológico foi feito durante dois anos nos municípios de Bagé e Cap o do Le o. As leituras foram mensais durante o período vegetativo e quinzenais no período reprodutivo das espécies, para observa o desde sua emergência até dispers o de sementes, avaliando-se o vigor, e relacionando essas variáveis com fatores ambientais. Os resultados permitiram concluir que durante todo o ano há emergência de plantas de Senecio spp, desde que haja condi es ambientais favoráveis, como umidade e luz, e as fenofases vegetativas s o praticamente constantes durante todo o ciclo da planta. Fatores ambientais desfavoráveis como o déficit hídrico, o manejo do solo e o dano de insetos, associados ou n o, podem alterar o ciclo das plantas e serem determinantes para a sua permanência no ambiente. A maioria dos exemplares, das quatro espécies, comportou-se como anual e monocárpica. A espécie mais persistente no ambiente foi S. heterotrichius (15% das plantas persistiram durante os dois anos de estudo), seguida de S. selloi (2,8%) e S. brasiliensis (0,9%). S. oxyphyllus n o permaneceu no ambiente por mais de um ano.
Terpenoids, flavonoids and other constituents of Eupatorium betonicaeforme (Asteraceae)
Albuquerque, Maria Rose Jane R.;Pires, Andreza Maria L.;Pessoa, Otília Deusdênia L.;Silveira, Edilberto R.;
Journal of the Brazilian Chemical Society , 2006, DOI: 10.1590/S0103-50532006000100010
Abstract: a new acylated kaurene diterpene, characterized as 15a-decanoyloxy-kaur-16-en-19-oic acid, along with nine known compounds: pentacosanoic acid, 24a-ethyl-5a-cholesta-7,22e-dien-3b-ol, 15a-hydroxy-kaur-16-en-19-oic acid, 8b-angeloyloxy-9b,10b-dihydroxy-1-oxo-germacra-4e,11(13)dien-12,6a-olide, 3b-hydroxyeicosan-1,5b-olide, taraxasteryl acetate, 7-o-methylkaempferol, kaempferol, and nepetin were isolated from the flowers of eupatorium betonicaeforme (asteraceae). in addition, from the aerial parts were isolated taraxasteryl acetate and a- and b-amyrin, while the mixture of b-sitosterol and stigmasterol, and 6-acetyl-2,2-dimethylchroman-4-one were isolated from the roots. the structure elucidation of all compounds was performed by spectroscopic analysis and comparison with published data from literature.
Terpenoids, flavonoids and other constituents of Eupatorium betonicaeforme (Asteraceae)  [cached]
Albuquerque Maria Rose Jane R.,Pires Andreza Maria L.,Pessoa Otília Deusdênia L.,Silveira Edilberto R.
Journal of the Brazilian Chemical Society , 2006,
Abstract: A new acylated kaurene diterpene, characterized as 15alpha-decanoyloxy-kaur-16-en-19-oic acid, along with nine known compounds: pentacosanoic acid, 24alpha-ethyl-5alpha-cholesta-7,22E-dien-3beta-ol, 15alpha-hydroxy-kaur-16-en-19-oic acid, 8beta-angeloyloxy-9beta,10beta-dihydroxy-1-oxo-germacra-4E,11(13)dien-12,6alpha-olide, 3beta-hydroxyeicosan-1,5beta-olide, taraxasteryl acetate, 7-O-methylkaempferol, kaempferol, and nepetin were isolated from the flowers of Eupatorium betonicaeforme (Asteraceae). In addition, from the aerial parts were isolated taraxasteryl acetate and alpha- and beta-amyrin, while the mixture of beta-sitosterol and stigmasterol, and 6-acetyl-2,2-dimethylchroman-4-one were isolated from the roots. The structure elucidation of all compounds was performed by spectroscopic analysis and comparison with published data from literature.
Phototoxic compounds and biological activity of extracts from Eupatorium morifolium Mill. (Asteraceae)
Pérez-Amador,MC; Mu?oz Ocotero,V; García Jiménez,F;
Phyton (Buenos Aires) , 2008,
Abstract: leaves of eupatorium morifolium mill. were analyzed for phototoxic compounds, and the toxicity of their hexane extract was evaluated against bacillus subtilis. the phototoxic compounds were analyzed by tlc. in the plate, pale blue spots indicated the presence of these compounds. this was confirmed by the uv extract spectrum and the antibacterial activity against bacillus subtilis. the biological activity of the leaf extracts (hexane, ethyl acetate or methanol) was also studied. the antiinflammatory activity was determined using the edema test on mouse ears, and the bactericide activity was assayed against bacillus subtilis and escherichia coli. a strong anti-inflammatory activity was shown by the leaf extracts. the ethyl acetate extract exhibited the strongest bactericide activity, followed by the methanol and hexane extracts.
EUPATORIUM RUFESCENS Y VERNONIA OLIGACTOIDES (ASTERACEAE), NUEVAS CITAS PARA LA FLORA ARGENTINA
álvaro José Vega,Massimiliano Dematteis
Bonplandia , 2010,
Abstract: Se mencionan por primera vez para la flora argentina a Eupatorium rufescens Lund ex DC. y Vernonia oligactoides Less. (Asteraceae). Ambas entidades son descriptas y se presenta una clave para diferenciarlas de taxones afines, junto con algunas informaciones ecológicas sobre las entidades
Eupatorium rufescens y Vernonia oligactoides (Asteraceae), nuevas citas para la flora argentina
álvaro J. Vega
Bonplandia , 2008,
Abstract: Se mencionan por primera vez para la flora argentina a Eupatorium rufescens Lund ex DC. y Vernonia oligactoides Less. (Asteraceae). Ambas entidades son descriptas y se presenta una clave para diferenciarlas de taxones afines, junto con algunas informaciones ecológicas sobre las entidades
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