30 research outputs found

    Secagem ao sol e a sombra, de sementes de Brachiaria humidicola (Rendle) Schweick., e seus efeitos sobre a qualidade fisiologica, durante o armazenamento

    Get PDF
    Orientador : Doris GrothDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia AgricolaResumo: Sementes de Brachiaria humidicola foram secas em escala piloto pelos seguintes processos de secagem: em secador giratorio ao sol e à sombra, sobre asfalto ao sol e à sombra, sobre concreto ao sol e à sombra, em estufa a 35°C e sem secagem. Os efeitos de cada tratamento de secagem foram avaliados sobre: a umidade, a pureza, a germinação e o vigor das sementes, imediatamente após a secagem e mensalmente durante um ano de armazenamento. Os resultados de germinação, após a secagem, evidenciaram a redução média de 16,8% nos tratamentos ao sol em relação aos à sombra. Não houve diferença entre as superficies asfalto e concreto. Os secadores giratórios proporcionaram os valores mais elevados de germinação e vigor, sem diferença quanto a exposição ao sementes logo após a secagem (r = 0,93), exceto para os tratamentos realizados nos secadores giratórios. Os lotes processados nestes secadores apresentaram vantagens, também, no teor de pureza e na coloração. O comportamento durante doze meses de armazenamento, manteve os efeitos que cada processo de secagem promoveu sobre a qualidade fisiolÓgica das sementes sol ou à sombra. O controle, sem secagem, apresentou alta germinaço apesar da presença de fungos. Obteve-se alta correlao linear entre a germinao e a umidade das logo após a sec:agem, quanto aos parametros pureza, germinaçaõ e vigor. Conc:luiu-se que dentre os proc:essos de sec:agem testados para sementes de Brachiaria humidicola, deve-se optar pela sec:agem à sombra ou nos sec:adores giratórios, para preservar a qualidade fisiolOgic:a das sementesAbstractMestradoMaquinas AgricolasMestre em Engenharia Agrícol

    Atividade in vitro de extratos de Artemisia annua L (Asteraceae) sobre Rhipicephalus (Boophilus) microplus

    Get PDF
    The activity of plant extracts on parasites may indicate groups of substances that are potentially useful for controlling Rhipicephalus (Boophilus) microplus. The aim of the present study was to investigate the in vitro action of Artemisia annua extracts on this tick. The concentrations of the sesquiterpene lactones artemisinin and deoxyartemisinin present in plant extracts were quantified via high-performance liquid chromatography. Four extracts produced from the concentrated crude extract (CCE) were evaluated on larvae using the impregnated paper method, with readings after 24 hours of incubation. The engorged females were immersed in the CCE and in its four derived extracts for five minutes, with incubation for subsequent analysis of biological parameters. The extracts were not effective on the larvae at the concentrations tested (3.1 to 50 mg.mL-1). The CCE showed greater efficacy on engorged females (EC50 of 130.6 mg.mL-1 and EC90 of 302.9 mg.mL-1) than did the derived extracts. These results tend to confirm that the action of artemisinin on engorged females of R.(B.) microplus is conditional to their blood intake. In this case, in vitro methods would be inadequate for effective evaluation of the action of A. annua on R. (B.) microplus.A atividade de extratos vegetais sobre parasitas pode indicar grupos de substâncias de uso potencial no controle de Rhipicephalus (Boophilus) microplus. O objetivo do presente estudo foi investigar a ação in vitro de extratos de Artemisia annua sobre esta espécie. A concentração das lactonas sesquiterpênicas artemisinina e deoxiartemisinina presentes nos extratos vegetais, foi quantificada via cromatografia líquida de alta eficiência. Quatro extratos produzidos a partir do extrato bruto concentrado (EBC) foram avaliados sobre larvas pela metodologia do papel impregnado, com leitura após 24 horas de incubação. As fêmeas ingurgitadas foram imersas por cinco minutos no EBC e nos seus quatro extratos derivados, e incubadas para posterior análise dos parâmetros biológicos. Os extratos não tiveram eficácia sobre as larvas nas concentrações avaliadas (de 3,1 a 50 mg.mL-1). O EBC apresentou melhor eficácia sobre as fêmeas ingurgitadas (CE 50 de 130,6 mg.mL-1 e CE 90 de 302,9 mg.mL-1) que os extratos derivados. Esses resultados tendem a confirmar que a ação da artemisinina sobre as fêmeas ingurgitadas de R. (B.) microplus estaria condicionada à sua ingestão através do sangue. Nesse caso, os métodos in vitro seriam inadequados para a efetiva avaliação da ação de A. annua R.(B.) microplus.313

    Biomassa e composição química de genótipos melhorados de espécies medicinais cultivadas em quatro municípios paulistas

    Get PDF
    The objective of this work was to evaluate the production and chemical constituents of selected genotypes of Artemisia annua, Cordia verbenaceae, Phyllanthus amarus and Mikania laevigata cultivated in Altinópolis, Campinas, Jales and São Carlos. Biomass variations, and qualitative and quantitative differences in plants chemical composition are observed among the locations, with higher values of interesting substances being detected in Jales.O objetivo deste trabalho foi avaliar a produção de biomassa e a composição química de genótipos selecionados de Artemisia annua (artemisia), Cordia verbenacea (erva-baleeira), Phyllanthus amarus (quebra-pedra) e Mikania laevigata (guaco), nos municípios de Altinópolis, Campinas, Jales e São Carlos, no Estado de São Paulo. Ocorrem variações na produção de biomassa, assim como diferenças qualitativas e quantitativas, na composição química das plantas, em função dos locais de cultivo, destacando-se os maiores rendimentos de princípios ativos na região de Jales

    Biomass and chemical composition of improved genotypes of medicinal plant species cultivated in four cities of São Paulo State, Brazil

    Get PDF
    The objective of this work was to evaluate the production and chemical constituents of selected genotypes of Artemisia annua, Cordia verbenaceae, Phyllanthus amarus and Mikania laevigata cultivated in Altinópolis, Campinas, Jales and São Carlos. Biomass variations, and qualitative and quantitative differences in plants chemical composition are observed among the locations, with higher values of interesting substances being detected in Jales.O objetivo deste trabalho foi avaliar a produção de biomassa e a composição química de genótipos selecionados de Artemisia annua (artemisia), Cordia verbenacea (erva-baleeira), Phyllanthus amarus (quebra-pedra) e Mikania laevigata (guaco), nos municípios de Altinópolis, Campinas, Jales e São Carlos, no Estado de São Paulo. Ocorrem variações na produção de biomassa, assim como diferenças qualitativas e quantitativas, na composição química das plantas, em função dos locais de cultivo, destacando-se os maiores rendimentos de princípios ativos na região de Jales.86987

    Seasonality Role on the Phenolics from Cultivated Baccharis dracunculifolia

    Get PDF
    Baccharis dracunculifolia is the source of Brazilian green propolis (BGP). Considering the broad spectrum of biological activities attributed to green proplis, B. dracunculifolia has a great potential for the development of new cosmetic and pharmaceutical products. In this work, the cultivation of 10 different populations of native B. dracunculifolia had been undertaken aiming to determine the role of seasonality on its phenolic compounds. For this purpose, fruits of this plant were collected from populations of 10 different regions, and 100 individuals of each population were cultivated in an experimental area of 1800 m2. With respect to cultivation, the yields of dry plant, essential oil and crude extract were measured monthly resulting in mean values of 399 ± 80 g, 0.6 ± 0.1% and 20 ± 4%, respectively. The HPLC analysis allowed detecting seven phenolic compounds: caffeic acid, ferulic acid, aromadendrin-4′-methyl ether (AME), isosakuranetin, artepillin C, baccharin and 2-dimethyl-6-carboxyethenyl-2H-1-benzopyran acid, which were the major ones throughout the 1-year monthly analysis. Caffeic acid was detected in all cultivated populations with mean of 4.0%. AME displayed the wide variation in relation to other compounds showing means values of 0.65 ± 0.13% at last quarter. Isosakuranetin and artepillin C showed increasing concentrations with values between 0% and 1.4% and 0% and 1.09%, respectively. The obtained results allow suggesting that the best time for harvesting this plant, in order to obtain good qualitative and quantitative results for these phenolic compounds, is between December and April

    In vitro susceptibility of Plasmodium falciparum Welch field isolates to infusions prepared from Artemisia annua L. cultivated in the Brazilian Amazon

    Get PDF
    Artemisinin is the active antimalarial compound obtained from the leaves of Artemisia annua L. Artemisinin, and its semi-synthetic derivatives, are the main drugs used to treat multi-drug-resistant Plasmodium falciparum (one of the human malaria parasite species). The in vitro susceptibility of P. falciparum K1 and 3d7 strains and field isolates from the state of Amazonas, Brazil, to A. annua infusions (5 g dry leaves in 1 L of boiling water) and the drug standards chloroquine, quinine and artemisinin were evaluated. The A. annua used was cultivated in three Amazon ecosystems (várzea, terra preta de índio and terra firme) and in the city of Paulínia, state of São Paulo, Brazil. Artemisinin levels in the A. annua leaves used were 0.90-1.13% (m/m). The concentration of artemisinin in the infusions was 40-46 mg/L. Field P. falciparum isolates were resistant to chloroquine and sensitive to quinine and artemisinin. The average 50% inhibition concentration values for A. annua infusions against field isolates were 0.11-0.14 μL/mL (these infusions exhibited artemisinin concentrations of 4.7-5.6 ng/mL) and were active in vitro against P. falciparum due to their artemisinin concentration. No synergistic effect was observed for artemisinin in the infusions

    In vitro susceptibility of Plasmodium falciparum Welch field isolates to infusions prepared from Artemisia annua L. cultivated in the Brazilian Amazon

    Get PDF
    Artemisinin is the active antimalarial compound obtained from the leaves of Artemisia annua L. Artemisinin, and its semi-synthetic derivatives, are the main drugs used to treat multi-drug-resistant Plasmodium falciparum (one of the human malaria parasite species). The in vitro susceptibility of P. falciparum K1 and 3d7 strains and field isolates from the state of Amazonas, Brazil, to A. annua infusions (5 g dry leaves in 1 L of boiling water) and the drug standards chloroquine, quinine and artemisinin were evaluated. The A. annua used was cultivated in three Amazon ecosystems (várzea, terra preta de índio and terra firme) and in the city of Paulínia, state of São Paulo, Brazil. Artemisinin levels in the A. annua leaves used were 0.90-1.13% (m/m). The concentration of artemisinin in the infusions was 40-46 mg/L. Field P. falciparum isolates were resistant to chloroquine and sensitive to quinine and artemisinin. The average 50% inhibition concentration values for A. annua infusions against field isolates were 0.11-0.14 μL/mL (these infusions exhibited artemisinin concentrations of 4.7-5.6 ng/mL) and were active in vitro against P. falciparum due to their artemisinin concentration. No synergistic effect was observed for artemisinin in the infusions
    corecore