11 research outputs found

    Chemical composition, circadian rhythm and antibacterial activity of essential oils of piper divaricatum: a new source of safrole

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    The essential oils from leaves, stems and fruits of Piper divaricatum were analyzed by GC-MS. The tissues showed high safrole content: leaves (98%), fruits (87%) and stems (83%), with yields of 2.0, 4.8 and 1.7%, respectively. This is a new alternative source of safrole, a compound widely used as a flavoring agent and insecticide. The leaf's oil showed antibacterial activity against gram-negative bacteria while safrole was active against Salmonella Typhimurium and Pseudomonas aeruginosa. In addition, the study of circadian rhythm of the safrole concentration in the essential oils of leaves showed a negligible variation of 92 to 98%

    Chemical composition, leishmanicidal and cytotoxic activities of the essential oils from Mangifera indica L. var. Rosa and Espada

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    Submitted by Kamylla Nascimento ([email protected]) on 2017-11-21T13:09:05Z No. of bitstreams: 1 art. Chemical Composition - ramos.pdf: 1214746 bytes, checksum: 59085409c9712afe7f9666dab9fce004 (MD5)Approved for entry into archive by Kamylla Nascimento ([email protected]) on 2017-11-21T13:39:23Z (GMT) No. of bitstreams: 1 art. Chemical Composition - ramos.pdf: 1214746 bytes, checksum: 59085409c9712afe7f9666dab9fce004 (MD5)Made available in DSpace on 2017-11-21T13:39:23Z (GMT). No. of bitstreams: 1 art. Chemical Composition - ramos.pdf: 1214746 bytes, checksum: 59085409c9712afe7f9666dab9fce004 (MD5) Previous issue date: 2014Fundação Oswaldo Cruz. Instituto Aggeu Magalhães. Recife, PE, Brasil.The essential oils from Mangifera indica var. Rosa and Espada latex were obtained by hydrodistillation and analyzed using GC-FID and GC-MS. Twenty-seven components were identified. The main compound in the essential oil from M. indica var. Espada (EOMiE) was terpinolene (73.6%). The essential oil of M. indica var. Rosa (EOMiR) was characterized by high amounts of β-pinene (40.7%) and terpinolene (28.3%). In the test for leishmanicidal activity against promastigotes forms of L. amazonensis, EOMiR and EOMiE showed IC50 (72 h) of 39.1 and 23.0 μg/mL, respectively. In macrophages, EOMiR and EOMiE showed CC50 of 142.84 and 158.65 μg/mL, respectively. However, both were more specific to the parasite than macrophages, with values of selectivity index of 6.91 for EOMiE and 3.66 for EOMiR. The essential oils were evaluated for their cytotoxicity against the human tumor cells HEp-2, HT-29, NCI-H292, and HL-60. The EOMiR and EOMiE were most effective against the HL-60, with IC50 values of 12.3 and 3.6 μg/mL, respectively. The results demonstrated that the essential oils of M. indica can destroy L. amazonensis and inhibit tumor cell growth. These findings contribute to the knowledge of the Brazilian biodiversity as a source of potential therapeutic agents

    Influência do período de armazenamento do caupi [Vigna unguiculata (L.) Walp.], tratado com óleos essenciais e fixos, no controle de Callosobruchus maculatus (Fabricius, 1775) (Coleoptera, Chrysomelidae, Bruchinae) Influence of the storage period of cowpea [Vigna unguiculata (L.) Walp.] treated with essential and fixed oils, for the control of Callosobruchus maculatus (Fabricius, 1775) (Coleoptera, Chrysomelidae, Bruchinae)

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    Compostos secundários obtidos de plantas podem ser utilizados no controle de Callosobruchus maculatus, como uma tática alternativa potencial aos inseticidas sintéticos. Foram testados óleos essenciais (Cymbopogon martini Roxb., Piper aduncum L., Piper hispidinervum C.DC., Melaleuca sp., Lippia gracillis Shau) e fixos (Helianthus annus L., Sesamum indicum L., Gossypium hirsutum L., Glycine max L. e Caryocar brasiliense Camb.), na concentração de 50µl/20g, de acordo com estudos anteriores. Grãos de caupi, cv. Sempre Verde, foram impregnados com os óleos, em recipientes de vidro e submetidos à agitação manual por dois minutos. Cada parcela de 20g foi infestada com oito fêmeas de C. maculatus com 0 a 48h de idade, durante quatro dias. Os óleos foram avaliados logo após a impregnação e aos 30, 60, 90 e 120 dias de armazenamento. Na primeira avaliação, todos os óleos essenciais provocaram 100% de mortalidade e para os óleos fixos, a mortalidade variou entre 35% (G. hirsutum) e 67,5% (G. max). Com o prolongamento do período de armazenamento, houve um aumento do número de ovos viáveis e de insetos emergidos, exceto para P. aduncum. Em relação aos óleos fixos, S. indicum, G. max, G. hirsutum e C. brasiliense foram os mais eficientes até os 30 dias de armazenamento. Os resultados indicam que os óleos testados na concentração de 50µl/20g apresentam baixo efeito residual, com exceção de P. aduncum, que foi efetivo durante todo o período de armazenamento.<br>The secondary compounds extracted from plants are considered potential alternative to synthetic insecticides in the control of agricultural pests. Essential oils (Cymbopogon martini Roxb., Piper aduncum L., P. hispidinervum C.DC., Melaleuca sp. and Lippia gracillis Shau) and fixed oils (Helianthus annus L., Sesamum indicum L., Gossypium hirsutum L., Glycine max L. and Caryocar brasiliense Camb.) at the concentration of 50µl/20g were tested according to previous studies. Samples of cowpea cv. Sempre Verde were impregnated with these oils in glass recipients and submitted to manual agitation for two minutes. Each plot of 20g was infested with eight females of C. maculatus up to 48 hours old, during four days. The oil efficiency was evaluated right after the impregnation and after 30, 60, 90 and 120 days of storage. In the first evaluation, all essential oils caused 100% of mortality and the fixed oils caused low mortality, varying from 35% (G. hirsutum) to 67,5% (G. max). With longer storage period, there was an increase in the number of viable eggs and emerged insects, except for P. aduncum. Among the fixed oils, S. indicum, G. max, G. hirsutum and C. brasiliense were the most efficient up to 30 days of storage. The results showed the low residual effect of the tested oils for the control of C. maculatus, excep P. aduncum, which was efficient throughout the 120 days of storage

    Estimativa de área de vegetação secundária na Amazônia Legal Brasileira Estimation of secondary vegetation area in the Brazilian Legal Amazon

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    A vegetação secundária tem funções relevantes para os ecossistemas, tais como a fixação de carbono atmosférico, a manutenção da biodiversidade, o estabelecimento da conectividade entre remanescentes florestais, manutenção dos regime hidrológico e a recuperação da fertilidade do solo. O objetivo deste trabalho é, através de uma abordagem amostral, estimar a área ocupada por vegetação secundária na Amazônia Legal Brasileira (AML) em 2006. A amostragem se baseia em uma abordagem estratificada pelo grau de desflorestamento das cenas LANDSAT-TM que recobrem a AML. Foram selecionadas 26 cenas para o ano de 2006, distribuídas em sete estratos conforme o percentual de desflorestamento, nas quais foram mapeadas as áreas de vegetação secundária a partir de técnicas de classificação de imagens. Foi desenvolvido um modelo multivariado de regressão para estimar a área de vegetação secundária utilizando como variáveis independentes a área de desflorestamento, a área de hidrografia, a estrutura agrária, e área das unidades de conservação. A análise de regressão encontrou um R2 ajustado de 0,84 , e coeficientes positivos para a proporção de hidrografia na imagem (2,055) e para a estrutura agrária (0,197), e coeficientes negativos para o grau de desflorestamento na imagem (-0,232) e para a proporção de Unidades de Conservação na imagem (-0,262). O modelo de regressão estimou uma área de 131.873 km² de vegetação secundária para o ano de 2006. Aplicando uma simulação Monte Carlo foi estimada uma incerteza de aproximadamente 12.445 km² para a área.<br>Secondary vegetation has many relevant functions to the ecosystems such as atmospheric carbon fixation , maintenance of biodiversity, establishment of connectivity among forest remnants, maintenance of hydrological regime, and restoration of soil fertility. The objective of this work is to estimate the area occupied by secondary vegetation in the Brazilian Legal Amazon (BLA) for 2006 using a sampling scheme. The sampling is based on a stratified approach according to the degree of deforestation observed in the 229 TM-Landsat scenes that cover the BLA. Thus, 26 scenes were selected for 2006 and distributed into seven strata, according to their degree of deforestation, in which secondary vegetation areas were mapped. A regression model was constructed to estimate secondary vegetation area in the remaining images using deforestation area, hydrographic area, agrarian structure , and area of conservation units, as independent variables. The regression analysis found an adjusted R2 of 0.84 and positive coefficients for the proportion of hydrography in the image (2.055) and for the agrarian structure (0.197), while negative coefficients for the degree of deforestation in the image (-0.232) as well as for the proportion of Conservation Unity(-0.262). Using the multivariate regression model, an area of 131,873 km² of secondary vegetation was estimated for the year of 2006. Applying a Monte Carlo simulation we estimated an uncertainty of approximately 12,445 km²
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