74 resultados para Aspidosperma parvifolium


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Four known alkaloids, uleine, epiuleine, apparicine and desmethyluleine, besides the isoprenoids lupeol and stigmasterol were isolated from the stem bark of Aspidosperma parvifolium. Their identification was based on spectroscopic analysis (UV, IR, ¹H-NMR, 13C-NMR, MS). The chromatographic profile of the ethanolic extract was obtained by HPLC and uleine, epiuleine and apparicine were identified in the extract.

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Species distribution modeling has relevant implications for the studies of biodiversity, decision making about conservation and knowledge about ecological requirements of the species. The aim of this study was to evaluate if the use of forest inventories can improve the estimation of occurrence probability, identify the limits of the potential distribution and habitat preference of a group of timber tree species. The environmental predictor variables were: elevation, slope, aspect, normalized difference vegetation index (NDVI) and height above the nearest drainage (HAND). To estimate the distribution of species we used the maximum entropy method (Maxent). In comparison with a random distribution, using topographic variables and vegetation index as features, the Maxent method predicted with an average accuracy of 86% the geographical distribution of studied species. The altitude and NDVI were the most important variables. There were limitations to the interpolation of the models for non-sampled locations and that are outside of the elevation gradient associated with the occurrence data in approximately 7% of the basin area. Ceiba pentandra (samaúma), Castilla ulei (caucho) and Hura crepitans (assacu) is more likely to occur in nearby water course areas. Clarisia racemosa (guariúba), Amburana acreana (cerejeira), Aspidosperma macrocarpon (pereiro), Apuleia leiocarpa (cumaru cetim), Aspidosperma parvifolium (amarelão) and Astronium lecointei (aroeira) can also occur in upland forest and well drained soils. This modeling approach has potential for application on other tropical species still less studied, especially those that are under pressure from logging.

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O estudo de produção de mudas florestais com potencial madeireiro adquire grande importância diante da necessidade de reposição dessas espécies devido à forte exploração comercial, recomposição de vegetação em áreas degradadas e utilização ornamental. O objetivo deste trabalho foi avaliar o crescimento inicial de mudas de três espécies florestais nativas, mulateiro (Calycophyllum spruceanum Benth.), amarelão (Aspidosperma parvifolium A.DC.) e freijó [Cordia alliodora (Ruiz & Pav.) Cham.] em diferentes substratos à base de resíduos agroflorestais. Os substratos testados foram Terra - Testemunha (T), Resíduo de Açaí Peneirado (RAP), (T)+(RAP) (1:1 v/v) e Casca de Amendoim Triturada (CAT) + Casca de Castanha Triturada (CCT) + Terra (T) (1:1:1 v/v/v) em delineamento inteiramente casualizado no arranjo fatorial 3x4 (três espécies x quatro substratos) resultando em 12 tratamentos, com cinco repetições de duas plântulas, totalizando em 120 unidades amostrais, sendo o crescimento das mudas observado por um período de 120 dias. Os parâmetros utilizados para avaliação do crescimento foram altura da parte aérea, diâmetro do colo, massa seca da parte aérea, das raízes e total. Dentre os substratos estudados, a composição CAT+CCT+T mostrou-se adequado para o cultivo do amarelão, freijó e mulateiro, no entanto, as mudas do último desenvolveram-se melhor no substrato terra.

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A vegetação de um trecho da floresta de restinga no Parque Estadual Paulo César Vinha (PEPCV), Setiba, município de Guarapari (ES) foi amostrada através de 100 parcelas de 10 × 10 m cada, plotadas em quatro linhas perpendiculares ao mar. Foram inventariados 2.106 indivíduos (DAP > 4,8 cm), fornecendo uma área basal de 27,52 m².ha-1 e diversidade (H') de 3,73 nats, excetuando os 67 mortos em pé. Segundo valores decrescentes de importância (VI), destacaram-se as famílias Myrtaceae, Sapotaceae, Annonaceae, Bombacaceae e Meliaceae, e as espécies Pouteria coelomatica, Myrciaria floribunda, Oxandra nitida, Chrysophyllum lucentifolium e Aspidosperma parvifolium. A floresta apresenta variações estruturais e florísticas no gradiente mar-continente, com formação de três grupos dissimilares de espécies. Ocorrência exclusiva de espécies nos grupos e diferenças entre os principais táxons de cada grupo, evidenciam uma zonação. Propõe-se o termo geral "formação florestal não inundável" para esta comunidade, frente aos tradicionais "Mata de Myrtaceae" e "Mata Seca", uma vez que a composição de suas principais famílias e espécies não permite separá-las de acordo com os critérios de classificação destas comunidades.

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A total of 24 extracts from 14 plant species collected at the state of Minas Gerais, Brazil, and belonging to five botanical families (Annonaceae, Apocynaceae, Ochnaceae, Polygonaceae and Vitaceae) was screened for cytotoxicity in cultured Vero cells and for antiviral activity against human herpes virus type 1 (HSV-1), vaccinia virus (VACV) and murine encephalomyocarditis virus (EMCV). The highest cytotoxicity (CC 50 < 10 μg/mL) was observed for the ethanol extracts from Annona coriacea fruits and seeds. Extracts from Hancornia speciosa, Ouratea castaneafolia and O. semisrrata were the only ones that have shown activity against all the three viruses assayed. Extracts from Polygonum spectabile, Hancornia speciosa, Himatanthus phagedaenica, Ouratea spectabilis and O. semiserrata were the most active against HSV-1 (EC 50 < 50 mg/mL), with favorable SI values (8.0 to 10.0). Hancornia speciosa and Anaxagorea dolichocarpa were the most active against EMCV (EC 50 50 - 100 μg/mL), with reasonable SI values (5.2 to 6.1), while moderate to low activity (EC 50 > 100 μg/mL) was observed for Ouratea spectabilis and O. semiserrata. A total of 7 plant species, Ouratea semiserrata, O. spectabilis, O. castanaeafolia, Rollinia laurifolia, Cissus erosa, Polygonum spectabile, and Hancornia speciosa, were active against VACV, disclosing EC50 < 50 μg/mL and SI values ranging from 6.6 to 67.3. In total, 10 out of the 14 species were selected from a literature survey on plants used to treat viral diseases in Brazil; these species were responsible for 70% of the positive results.

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The scientific research in seed technology is based on techniques that aim the reduction of costs and time, standardization, improvement and establishment of analytical methods while maintaining a high level of reliability of the results. This study sought to elucidate the reliability of electrical conductivity and pH of the exudate compared to the classic germination test, which was developed in two separate studies, however interrelated with each other, as to their final goals. The experimental material of this study consisted of seeds of the species Aspidosperma parvifolium (guatambu), Aspidosperma polyneuron (peroba-rosa), Cabralea canjerana (canjerana), Cariniana legalis (jequitibá), Gallesia integrifolia (pau-d'alho), Handroanthus chrysotrichus (ipê-amarelo), Lonchocarpus campestris (rabo-de-bugio) and Pterogyne nitens (amendoim-do-campo). The physiological quality of the studied seed species was evaluated through the electrical conductivity and pH test of the exudate by mass and individual methods being compared and correlated with the results obtained in the germination test. In addition to the tested methods, imbibition periods of the seeds were evaluated for conductivity and pH, which corresponded to 2, 4, 6, 8, 24 and 48 hours. The electrical conductivity test was efficient in both of the used methods to evaluate the physiological quality of the studied seed species when compared to the standard germination test. The pH test of the exudate applied by the individual method was more efficient and thorough to evaluate the physiological quality of the studied seed species, than the mass method. For the species Gallesia integrifolia, Cariniana legalis and Lonchocarpus campestris the pH tests of the exudate tests were not efficient due to poor or absent correlation between germination and pH.

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Informações etnomédicas mostram que algumas espécies de Aspidosperma (Apocynaceae) são utilizadas contra a malária no Brasil e motivaram a avaliação de 6 espécies que foram coletadas no Estado de Minas Gerais: A. cylindrocarpon Müll. Arg., A. parvifolium A. DC., A. olivaceum Müll. Arg., A. ramiflorum Müll. Arg., A. spruceanum Benth. ex Müll. Arg. and A. tomentosum Mart. Um total de 23 extratos de diferentes partes das plantas, em diferentes solventes, foram testados in vitro contra cepas de Plasmodium falciparum resistente a cloroquina (W2) e sensível a cloroquina (3D7). Todos os extratos mostraram-se ativos apresentando valores de CI50 na faixa de 5,0 ± 2,8 µg/mL a 65,0 ± 4,2 µg/ mL. O perfil por CCD dos extratos revelou a presença de alcalóides nas 6 espécies avaliadas. Esses resultados parecem confirmar o uso popular de espécies de Aspidosperma no tratamento da malária humana no Brasil e parecem indicar os alcalóides como possíveis compostos ativos das espécies testadas.

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Infections due to protozoa of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The drugs of choice for the treatment of leishmaniasis are the pentavalent antimonials (SbV), which present renal and cardiac toxicity. Besides, the precise chemical structure and mechanism of action of these drugs are unknown up to date. In order to find new drugs against leishmaniasis, we have been studying extracts of Brazilian trees. In the present study, we have evaluated the effectiveness of an alkaloid extract of Aspidosperma ramiflorum Muell. Arg. (Apocynaceae), against the extracellular forms promastigotes of L. (L.) amazonensis and L. (V.) braziliensis. The alkaloid extract of A. ramiflorum was much more effective against L. (L.) amazonensis (LD50 < 47 µg/ml) than L. (V.) braziliensis. Based on these in vitro results against L. (L.) amazonensis new studies should be made to find the compounds with anti-leishmanial activity.

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Infusions of Aspidosperma nitidum (Apocynaceae) wood bark are used to treat fever and malaria in the Amazon Region. Several species of this family are known to possess indole alkaloids and other classes of secondary metabolites, whereas terpenoids, an inositol and the indole alkaloids harmane-3 acid and braznitidumine have been described in A. nitidum . In the present study, extracts from the wood bark, leaves and branches of this species were prepared for assays against malaria parasites and cytotoxicity testing using human hepatoma and normal monkey kidney cells. The wood bark extracts were active against Plasmodium falciparum and showed a low cytotoxicity in vitro, whereas the leaf and branch extracts and the pure alkaloid braznitidumine were inactive. A crude methanol extract was subjected to acid-base fractionation aimed at obtaining alkaloid-rich fractions, which were active at low concentrations against P. falciparum and in mice infected with and sensitive Plasmodium berghei parasites. Our data validate the antimalarial usefulness of A. nitidum wood bark, a remedy that can most likely help to control malaria. However, the molecules responsible for this antimalarial activity have not yet been identified. Considering their high selectivity index, the alkaloid-rich fractions from the plant bark might be useful in the development of new antimalarials.

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Several species of Aspidosperma plants are used to treat diseases in the tropics, including Aspidosperma ramiflorum, which acts against leishmaniasis, an activity that is experimentally confirmed. The species, known as guatambu-yellow, yellowperoba, coffee-peroba andmatiambu, grows in the Atlantic Forest of Brazil in the South to the Southeast regions. Through a guided biofractionation of A. ramiflorum extracts, the plant activity against Plasmodium falciparum was evaluated in vitro for toxicity towards human hepatoma G2 cells, normal monkey kidney cells and nonimmortalised human monocytes isolated from peripheral blood. Six of the seven extracts tested were active at low doses (half-maximal drug inhibitory concentration < 3.8 µg/mL); the aqueous extract was inactive. Overall, the plant extracts and the purified compounds displayed low toxicity in vitro. A nonsoluble extract fraction and one purified alkaloid isositsirikine (compound 5) displayed high selectivity indexes (SI) (= 56 and 113, respectively), whereas compounds 2 and 3 were toxic (SI < 10). The structure, activity and low toxicity of isositsirikine in vitro are described here for the first time in A. ramiflorum, but only the neutral and precipitate plant fractions were tested for activity, which caused up to 53% parasitaemia inhibition of Plasmodium bergheiin mice with blood-induced malaria. This plant species is likely to be useful in the further development of an antimalarial drug, but its pharmacological evaluation is still required.

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The objective of this work was to assess the effects of Aspidosperma pyrifolium ethanol extracts on cabbage moth (Plutella xylostella) larvae. The ethanol extracts of the stem bark, fruits and roots of A. pyrifolium were obtained by classical phytochemical methods, and the resulting subfractions were tested on P. xylostella, using 4 and 5 mg L-1. The crude ethanol extract of the stem bark was more lethal. The alkaloid-rich aqueous subfraction derived from the stem bark extract caused 100% larval mortality at 4 mg L-1. Insecticidal activity was associated with the presence of the monoterpenoid indole alkaloids aspidofractinine, 15-demethoxypyrifoline, and N-formylaspidofractinine. These alkaloids presented excellent insecticidal properties against P. xylostella.

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Species from genus Aspidosperma (Apocynaceae) are popularly employed to treat various diseases. This genus is characterized by the occurrence of indole alkaloids. Taking into account the various biological activities attributed to these alkaloids, the description of the chemical diversity in genus Aspidosperma is important. A review of simple carbolinic alkaloids isolated from species of various genera was published in 1979. In 1987, it was published another one dealing with the relationships between the chemical structures of the indole alkaloids and the evolution of Aspidosperma species. This work updates the information about the indole alkaloids isolated from Aspidosperma species.

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Fractionation of extracts resulted in isolation and identification of indole alkaloids ellipticine and N-methyltetrahydroellipticine from A. vargasii and aspidocarpine from A. desmanthum. Identification of these compounds was achieved based on IR, MS, ¹H, 13C and 2-D NMR data and comparison to data in the literature.

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The population genetic structure of the endangered tree species Aspidosperma polyneuron Mull.Arg. (Apocynaceae) was reported based on analysis of esterase polymorphism in two remanant populations. Allelic variation was detected at three isoesterase loci (Est-3, Est-9, and Est-10). The proportion of polymorphic loci for both populations was 30% and deviation from Hardy-Weinberg equilibrium was observed for the Est-3 locus observed in the northern population. Segregation distortion and the lower level of observed and expected heterozygosity in this population were attributed to founder genotype. The high genetic identity values for northern and northwestern populations are in accordance with the low levels of interpopulation genetic divergence demonstrated by the F(ST) (0.03) value. The F(IS) value (0.23) indicated moderate levels of inbreeding. A. polyneuron can be indicated as an example of endangered species suggesting high genetic variation in contrast to the low genetic variation reported for endangered species. The esterase isozymes may be a good genetic marker for studies of natural A. polyneuron populations.

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O presente trabalho teve como objetivo o estabelecimento de um protocolo de regeneração in vitro de mudas de Aspidosperma polyneuron (peroba-rosa), a partir de segmentos nodais de material juvenil. Brotações apicais de mudas de dois anos de idade foram desinfestadas com 0,25% de hipoclorito de sódio ou 0,05% de cloreto de mercúrio, durante 10 min, visando ao estabelecimento de culturas assépticas. A indução de brotações múltiplas foi realizada em meio de cultura WPM, suplementado com BAP, ZEA ou CIN (2,2-8,8 miM), no cultivo inicial e nos dois subcultivos subseqüentes. Para indução de brotações alongadas foram testadas as combinações de fitorreguladores: 2,25 miM de BAP, ZEA ou CIN, associadas com 1,25 miM de AIB. A indução de raízes foi avaliada com tratamentos em soluções de AIB (2,5-10 mM), durante 5 ou 15 min. As mudas enraizadas foram transplantadas para casa de vegetação. A desinfestação das brotações apicais foi eficiente com 0,25% de NaOCl ou 0,05% de HgCl2, durante 10 min, obtendo-se 72,89 e 84,10% de sobrevivência, respectivamente. As maiores taxas médias de regeneração de brotações axilares (4 a 5) foram obtidas em meio de cultura suplementado com ZEA ou BAP (4,4-8,8 miM), após o segundo subcultivo. Concentrações mais reduzidas de BAP ou ZEA (2,25 miM) e 1,25 miM de AIB proporcionaram, em média, três brotações mais alongadas (1,5-2,5 cm de comprimento). Tratamentos com soluções de 10 mM de AIB, durante 15 min, foram eficientes na indução de raízes (80%), e as mudas transplantadas apresentaram taxas de sobrevivência superiores a 90% em casa de vegetação.