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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Isolamento de microrganismos endof?ticos de Lippia gracilis Schauer (Verbenaceae), avalia??o do ?leo essencial da planta e dos metab?litos dos endof?ticos sobre a corros?o microbiologicamente induzida (CMI) em a?o carbono AISI 1020

Viana, Marcelino Gevilbergue 31 August 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-12-12T19:35:46Z No. of bitstreams: 1 MarcelinoGevilbergueViana_TESE.pdf: 5841614 bytes, checksum: a1942694c0220572b2895b7fa57c26cc (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-12-14T18:31:11Z (GMT) No. of bitstreams: 1 MarcelinoGevilbergueViana_TESE.pdf: 5841614 bytes, checksum: a1942694c0220572b2895b7fa57c26cc (MD5) / Made available in DSpace on 2017-12-14T18:31:11Z (GMT). No. of bitstreams: 1 MarcelinoGevilbergueViana_TESE.pdf: 5841614 bytes, checksum: a1942694c0220572b2895b7fa57c26cc (MD5) Previous issue date: 2017-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A corros?o microbiologicamente induzida (CMI) atinge todos os setores de produ??o da ind?stria de petr?leo e g?s e demanda expressivos gastos e investimentos para preven??o e controle. O objetivo dessa tese foi avaliar as atividades biocida e antibiofouling de metab?litos de microrganismos endof?ticos de Lippia gracilis Schauer como tamb?m do ?leo essencial (puro e em sistema microemulsionado) dessa esp?cie sobre biofilmes microbianos em a?o carbono 1020 AISI. Os experimentos utilizaram cupons de a?o carbono 1020 AISI dispostos em Erlenmyers e em sistema din?mico para a obten??o dos biofilmes. A avalia??o biocida dos metab?litos deu-se pela quantifica??o microbiana pelas t?cnicas de absorb?ncia, do n?mero mais prov?vel (NMP), antes e ap?s os tratamentos. Os tratamentos consistiram em: 0, 100, 150 e 200 ?g/L de cada metab?lito sobre biofilmes nos tempos de contato zero, duas, tr?s e quatro semanas, com tr?s repeti??es por tratamentos. A a??o antibiofouling foi realizada pelo contato dos metab?litos na maior concentra??o (200 ?g/L) com os biocupons antes da obten??o dos biofilmes. A a??o antimicrobiana do ?leo essencial de L. gracilis Schauer na forma pura, e em sistema microemulsionado, foi avaliada pela quantifica??o de bact?rias redutoras de sulfato (BRS), oxidantes de ferro (BOF), fungos, bact?rias aer?bias e anaer?bias totais, pelas t?cnicas de NMP, plaqueamento pour plate, espectrofotometria de massa (EM) e an?lise de micrografias realizadas antes e ap?s os tratamentos. A atividade anticorrosiva foi avaliada por imped?ncia e polariza??o eletroqu?micas, testes gravim?tricos (perda de massa e quantifica??o de pites) bem como pela obten??o de micrografias da superf?cie do a?o carbono. Amostras de L. gracilis Schauer foram coletadas no munic?pio de Mossor? - RN e foram isolados fungos e bact?rias das ra?zes e folhas. Uma nova esp?cie de fungo foi descoberta e identificada como Achaetomium lippae. Foram obtidos tr?s metab?litos: dois de fungos e um de bact?ria. Os resultados mostraram que houve diferen?a da atividade biocida e antibiofouling entre os metab?litos de endof?ticos de L. gracilis Schauer avaliados, sendo LGS-Rb1 o mais eficiente na maioria tipos microbianos testados, evitando a forma??o de biofouling e reduzindo a taxa de crescimento microbiano na maior concentra??o avaliada. Os ensaios eletroqu?micos e gravim?tricos mostraram que para todos os metab?litos houve varia??o na atividade anticorrosiva. O ?leo essencial de L. gracilis Schauer avaliado in natura inibiu significativamente o crescimento in vitro de C. bifermentans e de fungos em biofilme, reduzindo sua taxa de crescimento a zero a partir de 20 ?g.L-1. Os ensaios eletroqu?micos e gravim?tricos mostraram que a concentra??o de 60 ?g.L-1 do ?leo essencial foi eficiente na redu??o da corros?o. Nos ensaios usando o sistema microemulsionado o ?leo essencial inibiu eficientemente o crescimento de BRS, BOF e fungos ap?s 16 dias de contato e teve atividade antibiofouling ap?s 96 horas de contato com os biocupons de a?o carbono AISI 1020. Dessa forma os metab?litos de endof?ticos de L. gracilis Schauer bem como seu ?leo essencial mostram-se como novas alternativas de biocidas naturais eficientes no controle da corros?o microbiologicamente induzida. / The corrosion microbiologically induced (CMI) reaches all the sectors of production of the industry in Petroleum oil and Gas and demands expressive expensive and investments for prevention and control. The goal of this thesis was to evaluate the biocide and antibiofouling activities of secondary metabolites obtained from endophytic microorganisms of Lippia gracilis Schauer as well of the essential oil (pure and in microemulsified system) from this species on microbial biofilms in 1020 AISI carbono steel. The experiments for biocide activity used 1020 AISI carbon steel plate arranged in Erlenmyers and dynamic system with forced circulation for obtaining of the total biofilms from water produced by oil. The assessment for biocide of the metabolites from endophytic of L. gracilis Schauer resulted of the quantification of these species of bacteria in the quantification techniques by absorbance in more probable numbers (MPN), before and after the treatments, had been identified by gas chromatography coupled the spectrophotometry in mass (CG-MS) and magnetic resonance imaging (MRI) just those who demonstrated activities. The treatments consisted in evaluating the concentrations 0, 100, 150 and 200 ?g/L in each metabolites on biofilms in times contact to zero, two, three and four weeks, with three repetition by treatments. The antibiofouling action was made in the contact of the metabolites in the highest concentration (200 ?g/L) with the bioplates before being inserted into the dynamic system. The antimicrobial action of the essential oil L. gracilis Schauer in the pure form and in a microemulsified system was evaluated by the quantification bacteria reducer of sulphate (BRS), oxidant of iron (BOI), fungi, aerobic bacteria and total anaerobes by the techniques of dilution, platingpourplate, spectrophotometry in mass (MS) and micrographs analysis made before and after the treatments. The anticorrosive activity of all bioproducts was evaluated by electrochemical impedance and polarization, gravimetric examinations of mass loss and quantification of pites, as well in the obtaining of micrographs of the carbon steel`s surface. Samples of L. gracilis Schauer were collected in the city of Mossor? - RN and were isolated fungi and bacteria from the roots and leaves. A new type of fungus was discovered and identified as Achaetomium lippae. Three metabolites were obtained: two fungi (LGS-Lf1 and LGS-Lf2, being "LGS" for L. gracilis Schauer, "L": leaf, ?f?: fungus and "R" for root) and one of bacteria (LGS-Rb1, being "LGS" for L. gracilis Schauer, "R": root and "b": bacterium). The results showed that there was a difference in the biocide activity and antibiofouling between the metabolites from endophytic of L. gracilis Schauer assessed, being just the LGS-Lf1 being efficient over all the microorganisms tested, avoiding the formation of biofouling on the surface of the material and reducing the rate of microbial growth at zero after 96 hours of contact at the highest concentration evaluated. The electrochemical and gravimetric tests displayed that for all the metabolites occured change in the anticorrosive activity. The L. gracilis Schauer essential oil evaluated in the pure form inhibited significally the growth in vito of C. bifermentans and of fungi in biofilm, reducing their growth rate to zero as from 20 ?g.L-1. The electrochemical and gravimetric tests showed that the concentration of 60 ?g.L-1 of the essential oil was efficient in the reduction of corrosion. In the tests, using the microemulsified system, the essential oil inhibited the growth of BRS, BOF and fungi 16 days later in contact and had antibiofouling activity after 96 hours in contact with the AISI 1020 bioplates of carbon steel. Therefore, the metabolites from endophytic of L. gracilis Schauer as well its essential oil are shown as new alternatives of natural biocides efficient in the control of the corrosion microbiologically induced.
52

The genome of Euglena gracilis : annotation, function and expression

Ebenezer, ThankGod Echezona January 2018 (has links)
Euglena gracilis is a species of unicellular photosynthetic flagellate that inhibits aquatic ecosystems. E. gracilis belongs to the supergroup Excavata, and are an important component of the global biosphere, have biotechnological potential and is useful biological model due to their evolutionary history and complex biology. Whilst the evolutionary position of E. gracilis is now clear, their relationship with other protists such as Naegleria, Giardia, and Kinetoplastids, remains to be investigated in detail. Investigating and understanding the biology of this complex organism is a promising way to approach many evolutionary puzzles, including secondary endosymbiotic events and the evolution of parasitism, due to their relationship with Kinetoplastids. Here, I report a draft genome for E. gracilis, together with a high quality transcriptome and proteomic analysis. The estimated genome size is ~ 2 Gbp, with a GC content of ~ 50 % and a protein coding potential predicted at 36,526 Open Reading Frames (ORFs). Less than 25% of the genome is single copy sequence, indicating extensive repeat structure. There are evidences for large number of paralogs amongst specific gene families, indicating expansions and possible polyploidy as well as extensive sharing of genes with other non photosynthetic and photosynthetic eukaryotes: red and green algael genes, together with trypanosomes and other members of the excavates. Functional resolution into several of the biological systems indicates multiple similarities with the trypanosomatids in terms of orthology, paralogy, relatedness and complexity. Several biological systems such as nuclear architecture (e.g. chromosome segregation, nuclear pore complex, nuclear lamins), protein trafficking, translation, surface, consist of conserved and divergent components. For instance, several gene families likely associated with the cell surface and signal transduction possess very large numbers of lineage-specific paralogs, suggesting great flexibility in environmental monitoring and, together with divergent mechanisms for metabolic control, novel solutions to adaptation to extreme environments. I also demonstrate that the majority of control of protein expression levels is post-transcriptional and absence of transcriptional regulation, despite the presence of conventional introns. These data are a major advance in the understanding of the nuclear genome of Euglenids and provide a platform for investigation of the contributions of E. gracilis and relatives to the biosphere.
53

Atividade citotóxica do óleo essencial de Lippia spp. frente a células da linhagem A549 de carcinoma de pulmão humano / Cytotoxic activity of the essential oil of Lippia spp. facing cells of A549 line of human lung carcinoma

Almeida, Patrícia de Oliveira Santos 17 April 2016 (has links)
The lung carcinomas stand out as a major public health problem, therefore, are among the leading causes of cancer death worldwide. They are classified into two major histological groups: small cell lung carcinome (SCLC) and non small cell lung carcinoma non (NSCLC). In the search for novel therapies, many natural products derived from plants and other organisms has been studied for use as a source for the development of chemotherapeutic agents used in the treatment of various cancers, including carcinomas of the lung. In this context, the essential oils is part of medicinal plants produced by such as the genus Lippia that have many therapeutic properties, among them, antimicrobial, anti-inflammatory and antiproliferative. This study proposes to investigate the cytotoxic activity of essential oils of different species and genotypes of the genus Lippia plants. the Active Germplasm Bank of the Federal University of Sergipe (UFS) located at the Experimental Farm "Rural Campus of the UFS," which have varied chemical composition. For this A549 cells (lung carcinoma) were treated with increasing concentrations (20-160 / mL) essential oils Lippia gracilis (genotypes 106 and 110) of Lippia alba (genotypes 13:57) and Lippia sidoides (genotypes 102 and 104) during the 24 hour interval. Cytotoxicity of these essential oils was determined by the MTT colorimetric method. The absorbance values obtained in the treatments were normalized to the untreated cells and used to calculate IC50 values by regression analysis. IC50 values of 75.42 and 158.6 ug / ml were obtained for the LG-106 and LG-110 genotypes, respectively. For LS-102 and LS-104 genotypes IC50 were respectively 97.93 and 150.70 mg / mL and LA-13 and LA-57 genotypes these values were 86.14 and 70.34 mg / mL . Microscopic analysis of cells stained by hematoxylin-eosin showed morphological changes, including condensation of cytoplasm, chromatin condensation and nuclear fragmentation induced by all genotypes. These results suggest that the cytotoxic activity presented by the essential oils of Lippia on A549 lineage cells involves induction of programmed cell death. Therefore, it is concluded that these oils represent a promising source compounds for the development of new anti-tumor therapies. / Os carcinomas de pulmão destacam-se como um grave problema de saúde pública, pois, encontram-se entre as principais causas de morte por câncer no mundo. São classificados em dois principais grupos histológicos: carcinoma de pulmão de células pequenas (CPCP) e carcinoma de pulmão de células não pequenas (CPCNP). Na busca por terapias inovadoras, diversos produtos naturais derivados de plantas e outros organismos têm sido estudados para utilização como fonte para o desenvolvimento de quimioterápicos empregados no tratamento de diversos tipos de câncer, inclusive dos carcinomas de pulmão. Nesse contexto, insere-se os óleos essenciais produzidos por plantas medicinais como as do gênero Lippia que apresentam diversas propriedades terapêuticas, dentre elas, atividade antimicrobiana, antinflamatória e antiproliferativa. O presente trabalho propõe a investigação da atividade citotóxica dos óleos essenciais de diferentes espécies e genótipos de plantas do gênero Lippia. do Banco Ativo de Germoplasma da Universidade Federal de Sergipe (UFS), localizado na Fazenda Experimental “Campus Rural da UFS”, que apresentam variada composição química. Para isso as células A549 (Carcinoma de pulmão), foram tratadas com concentrações crescentes (20 a 160 μg/mL) de óleos essenciais de Lippia gracilis (genótipos 106 e 110), de Lippia alba (genótipos 13 e 57) e Lippia sidoides (genótipos 102 e 104) durante o intervalo de 24 horas. A citotoxicidade destes óleos essenciais foi determinada pelo método colorimétrico do MTT. Os valores das absorbâncias obtidas nos tratamentos foram normalizados com os das células não tratadas e utilizados para calcular os valores de IC por análise de regressão. Valores de IC50 de 75,42 e 158,6 μg/mL foram obtidos para os genótipos LG-106 e LG-110, respectivamente. Para os genótipos LS-102 e LS-104 as IC50 foram, respectivamente, 97,93 e 150,70 μg/mL e para os genótipos LA-13 e LA-57 estes valores foram 86,14 e 70,34 μg/mL. A análise microscópica das células coradas por hematoxilina-eosina revelou alterações morfológicas incluindo condensação do citoplasma, condensação da cromatina e a fragmentação nuclear induzidas por todos os genótipos avaliados. Estes resultados sugerem que atividade citotóxica apresentada pelos óleos essenciais de Lippia sobre células da linhagem A549 envolve a indução de morte celular programada. Com isso, conclui-se que tais óleos representam uma fonte promissora de compostos para o desenvolvimento de novas terapias antitumorais. / São Cristóvão, SE
54

Desenvolvimento de método por CLAE-DAD para discriminação de chás de genótipos de Lippia gracilis Schauer através de cromatogramas fingerprint combinados com análises quimiométricas

Prado, Vilma Menezes de Jesus 29 February 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / To evaluate the effects of the environmental on the content of secondary metabolites in the genotypes of Lippia gracilis Schauer, a high-performance liquid chromatographic-photodiode array detection (HPLC-DAD) method was developed to obtain the chemical profiles (fingerprints) of infusions from leaves of seven genotypes of L. gracilis originated from two locations (Sergipe and Bahia state) and collected in different seasons: summer (with and without irrigation) and winter. In order to compare the fingerprints chromatograms, it was applied chemometric tools for exploratory analysis (PCA). The results of these analyses showed that 108 and 202 genotypes collected in summer and grown without irrigation are significantly different from other genotypes under the same conditions. Moreover, knowing that this species is drought-resistant and can withstand high temperatures, we can propose that the 107, 108 and 110 genotypes are more resistant to drought conditions because there were no differences between samples collected in summer and grown with or without irrigation. All samples was submitted to antioxidant activity by DPPH method (2,2-diphenyl-1-picrylhydrazyl). The samples of 201 genotype collected in summer with and without irrigation, 201vc and 201vs (30 μg/mL; 60 min), respectively, exhibited more than 90% DPPH scavenging activities, displaying similar response to the positive control, gallic acid (92.06%, 30 mg/mL, 60 min). / Para avaliar os efeitos do meio ambiente no conteúdo de metabólitos secundários em genótipos de Lippia gracilis Schauer, um método por cromatografia líquida de alta eficiência com detector por arranjo de diodos (CLAE-DAD) foi desenvolvido para obter os perfis cromatográficos (fingerprint) de chás das folhas secas de sete genótipos desta espécie provenientes de duas localizações (Sergipe e Bahia) e coletadas em diferentes estações do ano: verão (com e sem irrigação) e inverno. Para comparar os cromatogramas fingerprints foi aplicado ferramentas quimiométricas de análise exploratória (ACP). Os resultados destas análises mostraram que os genótipos 108 e 202 coletados no verão e cultivados sem irrigação são significativamente diferentes dos demais genótipos da mesma coleta. Além disso, sabendo que esta espécie possui grande resistência à seca e a altas temperaturas, pode-se propor que os genótipos 107, 108 e 110 apresentaram maior resistência ao stress hídrico, pois não foi observada diferenciação entre as amostras coletadas no verão cultivadas com e sem irrigação. Os chás das amostras de L. gracilis foram também submetidos ao teste de atividade antioxidante pelo método DPPH (2,2 difenil-1-picril hidrazil). As amostras do genótipo 201, verão com irrigação e verão sem irrigação [(201 vc e 201 vs); 30 μg/mL; 60 min)] consumiram mais de 90% do radical DPPH, apresentando uma resposta similar ao controle positivo ácido gálico (92,06%, 30 μg/mL, 60 min).
55

Potencial citotóxico e antimicrobiano de plantas da reserva florestal Adolpho Ducke, Manaus-AM

Carneiro, Ana Lúcia Basílio 15 June 2015 (has links)
Submitted by Alisson Mota (alisson.davidbeckam@gmail.com) on 2015-07-13T18:17:07Z No. of bitstreams: 1 Tese - Ana Lúcia Basílio Carneiro.pdf: 16610047 bytes, checksum: c4cd629d2777cd22001ca4ee47db8b8c (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-15T18:51:06Z (GMT) No. of bitstreams: 1 Tese - Ana Lúcia Basílio Carneiro.pdf: 16610047 bytes, checksum: c4cd629d2777cd22001ca4ee47db8b8c (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2015-07-15T18:57:21Z (GMT) No. of bitstreams: 1 Tese - Ana Lúcia Basílio Carneiro.pdf: 16610047 bytes, checksum: c4cd629d2777cd22001ca4ee47db8b8c (MD5) / Made available in DSpace on 2015-07-15T18:57:21Z (GMT). No. of bitstreams: 1 Tese - Ana Lúcia Basílio Carneiro.pdf: 16610047 bytes, checksum: c4cd629d2777cd22001ca4ee47db8b8c (MD5) Previous issue date: 2015-06-15 / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / Tropical forests are species-rich reserves for the discovery and development of antimicrobial drugs. The aim of this work is to investigate the in vitro antimicrobial potential of Amazon plants found within the National Institute on Amazon Research’s Adolpho Ducke forest reserve, located in Manaus, state of Amazonas, Brazil. 75 methanol, chloroform and water extracts representing 12 plant species were tested for antimicrobial activity towards strains of Mycobacterium smegmatis, Escherichia coli, Streptococcus sanguis, Streptococcus oralis, Staphylococcus aureus and Candida albicans using the gel-diffusion method. Active extracts were further evaluated to establish minimum inhibitory concentrations (MIC) and antimicrobial profiles using bioautography on normal-phase thin-layer chromatography plates. Diclinanona calycina presented extracts with good antimicrobial activity and S. oralis and M. smegmatis were the most sensitive bacteria. D. calycina and Lacmellea gracilis presented extracts with the lowest MIC (48.8 μg/ml). D. calycina methanol and chloroform leaf extracts presented the best overall antimicrobial activity. All test organisms were sensitive to D. calycina branch chloroform extract in the bioautography assay. This is the first evaluation of the biological activity of these plant species and significant in vitro antimicrobial activity was detected in extracts and components from two species, D. calycina and L. gracilis. / O objetivo deste trabalho foi avaliar a atividade citotóxica, antitumoral e antimicrobiana de espécies vegetais amazônicas da Reserva Florestal Adolpho Ducke do Instituto Nacional de Pesquisas da Amazônia (INPA). As espécies vegetais sem estudos anteriores selecionadas e coletadas foram: Diclinanona calycina Benoist, (Annonaceae), Lacmellea gracilis (Mull. Arg.) Markgr. (Apocynaceae), Pleurisanthes parviflora (Ducke) Howard (Icacinaceae), Dilkea johannesii Berb. Rodr. (Passifloraceae), Sterigmapetalum obovatum Kuhlm. (Rhizophoraceae), Elaeoluma nuda (Baehni) Aubrév. (Sapotaceae). Após coleta e extração as amostras foram avaliadas quanto a citotoxicidade frente a Artemia franciscana e em linhagens de células tumorais. O potencial antimicrobiano foi determinado pelo método de difusão em ágar frente a Mycobacterium smegmatis, Escherichia coli, Streptococcus sanguis, S. oralis, Staphylococcus aureus e Candida albicans. Extratos ativos foram conduzidos a avaliação da concentração inibitórioa mínima (CIM) e bioautografia para identificar Rfs de componentes antimicrobianos. Prospecção fitoquímica das espécies promissoras foi realizada para detecção dos principais constituintes químicos. Dos 38 extratos avaliados para toxicidade em A. franciscana, dois apresentaram valores de CL50 inferiores a 100 μg/mL, portanto, tóxicos para essa espécie. A menor CL50 foi do extrato de D. calycina obtido em clorofórmio com valor de 22,9 ± 0,8 μg/mL. No screening para atividade antitumoral, nove extratos representando quatro espécies vegetais foram considerados muito ativos (MA) frente à célula tumoral de sistema nervoso (E. nuda e S. obovatum), cólon (S. obovatum), mama (E.nuda) e leucemia (L. gracilis, P. parviflora, S. obovatum). A maioria dos 75 extratos analisados inibiram o crescimento dos microrganismos teste com halos entre 8 e 40 mm de diâmetro. Extratos de D. calycina demonstraram atividade antimicrobiana com CIM de 48,8 μg/mL frente a S. aureus, S. oralis e S. sanguis e 97,7 μg/mL e 195 μg/mL frente a M. smegmatis. L. gracilis foi ativa apenas contra M. smegmatis (CIM 48,8 μg/mL). A bioautografia confirmou o potencial antimicrobiano de D. calycina e L. gracilis. Todos os microrganismos avaliados por bioautografia foram sensíveis ao extrato de galho de D. calycina obtido em clorofórmio. Na prospecção fitoquímica detectou-se a presença de fenóis, taninos, flavonóides, alcalóides e antraquinonas, em extratos de D. calycina e antraquinonas e cumarinas na espécie L. gracilis. Assim, a seleção permitiu identificar espécies vegetais amazônicas com atividade antimicrobiana e antitumoral in vitro e sugerir as espécies D. calycina, L. gracilis, E. nuda e S. obovatum para apreciação detalhada em outros estudos, pois poderão ter aplicação terapêutica no tratamento de doenças infecciosas e câncer.
56

Atividade larvicida do óleo essencial de plantas existentes no Estado de sergipe contra Aedes aegypti Linn

Silva, Wellington José da 29 March 2006 (has links)
O Aedes aegypti (Linn, 1762) é atualmente o mosquito que apresenta maior dispersão em áreas urbanas do mundo. Esta espécie é de grande importância para a medicina pois, trata-se do vetor de quatro sorotipos do flavivírus causador do dengue clássico e da febre hemorrágica do dengue. O aumento na densidade desse mosquito está relacionado ao comportamento sinantrópico e ao hábito antropofílico desssa espécie. Urge, portanto, o controle da densidade populacional do A. aegypti para que o dengue não assuma proporções de uma epidemia. Não existe vacina para o dengue, e a melhor forma de combater a doença é atacar o vetor, principalmente eliminando os locais onde ocorre a oviposição e o desenvolvimento das larvas do A. aegypti. Atualmente esse controle é feito por meio de aplicações de inseticidas organafosforados. Porém, o uso freqüente e em doses cada vez maiores desses produtos, têm selecionado populações resistentes do mosquito. Em todo o mundo diversas pesquisas são desenvolvidas no sentido de encontrar substância de origem vegetal, como alternativa para o controle do dengue. Os óleos essenciais, produzidos no metabolismo secundário das plantas, têm apresentado atividades inseticidas, larvicidas, fumigantes, deterrentes e outras. Este trabalho teve como objetivo identificar óleos essenciais de plantas do Estado de Sergipe com atividade larvicida contra o Aedes aegypti (Linn, 1762). Foram testados os óleos essenciais de Croton heliotropiifolius, Croton pulegiodorus, Hyptis fruticosa, Hyptis pectinata e Lippia gracilis. O óleo essencial das folhas foi extraído por hidrodestilação, com arraste de vapor, usando um aparelho de Clevenger. A análise dos óleos essenciais foi feita por cromatografia gasosa acoplado a um espectômetro de massas (CG/EM). Os ensaios larvicidas foram realizados utilizando-se 20 larvas por teste, em um béquer contendo 20ml de água mineral (26-28°) e mais a solução teste nas concentrações pré-estabelecidas para cada planta. Os testes foram feitos em quintuplicata para cada concentração. A análise dos dados foi feita de acordo com o método Reed-Muench (Colegate & Molyneux, 1993), estimando-se uma CL50 de 550,68; 158,81; 502,68; 366,35 e 98,06 mg L-1 respectivamente para Croton heliotropiifolius, Croton pulegiodorus, Hyptis fruticosa, Hyptis pectinata e Lippia gracilis. Todos os óleos testados foram ativos contra as larvas do Aedes aegypti, porém o óleo essencial de Lippia gracilis apresentou a melhor atividade. Além disso, o óleo de L. gracilis teve o maior rendimento, que foi de 7%. Isto sugere que o óleo essencial dessa espécie vegetal, pode ser uma alternativa no combate ao vetor do dengue, diminuindo o impacto sobre o ambiente e a saúde da população.
57

Risk-Prone and Risk-Averse Foraging Strategies Enable Niche Partitioning in Two Diurnal Orb-Weaving Spider Species

Long, Mitchell, Jones, Thomas C., Moore, Darrell, Yampolsky, Lev 07 April 2022 (has links)
Niche partitioning is a major component in understanding community ecology and how different species divide limited environmental resources, enabling them to coexist. Temporal niche partitioning has been widely studied in a broad sense, such as in species that forage on similar nutritional sources dividing activity along diurnal and nocturnal classifications. Here, we approach this temporal niche partitioning with higher resolution to investigate partitioning between species within the same broad temporal and foraging niche. Two species of diurnal orb-weaving spiders (Araneae: Araneidae), Verrucosa arenata and Micrathena gracilis, both construct their orbs in spatially similar locations throughout the understory of deciduous forests in the morning, forage on flying insects throughout the day, and retreat in the evening. However, despite consisting of what appear to be roughly similar total lengths of adhesive silk in the capture spiral, overall orb structure is starkly different: V. arenata orbs are relatively large in diameter and sparse with capture threads; M. gracilis orbs, condensed in diameter and tightly coiled. What other differences might distinguish foraging strategy within this same niche? With extensive observation in their natural environment, we have found that these two species employ two distinct strategies by modulating behavior and orb structure: V. arenata construct orbs earlier in the day, resulting in a longer foraging period. However, V. arenata webs are more likely to be destroyed during the day such that there is a higher variance in foraging duration in V. arenata. We also found that V. arenata actively capture and consume more large prey and that M. gracilis more passively capture and consume small prey more reliably. These data suggest that these species have evolved different foraging strategies with V. arenata being risk-prone and M. gracilis being risk-averse. This study provides a more nuanced analysis of niche partitioning between species occupying otherwise similar temporal, habitat, and foraging niches.
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Redescrição e ciclo de vida de Clytia gracilis e Clytia linearis (Cnidaria, Hydrozoa, Campanulariidae). / Redescription and life cycle of Clytia gracilis and Clytia linearis (Cnidaria, Hydrozoa, Campanulariidae).

Lindner, Alberto 19 December 2000 (has links)
Os ciclos de vida de Clytia linearis (Thornely, 1899) e de duas espécies apresentando caracteres considerados diagnósticos de Clytia gracilis (M. Sars, 1850) – aqui denominadas Clytia cf. gracilis sp. 1 e Clytia cf. gracilis sp. 2 – foram estudados com base em espécimes coletados no infralitoral raso da costa de São Sebastião e Ilhabela, sudeste do Brasil, entre fevereiro de 1999 e abril de 2000. Medusas foram cultivadas em laboratório, a temperatura de 22-24oC. Colônias de C. linearis são monossifônicas, simpodiais, com até 21,5mm de altura e portando até 26 hidrantes e 10 gonângios. Medusas adultas, alcançando 2,5-3,6mm de diâmetro e até 29 tentáculos e 28 estatocistos, podem ser distinguidas de outras espécies de Clytia pela presença de nematocistos microbásicos mastigóforos do tipo C. Medusas adultas de Clytia cf. gracilis spp. 1 e 2 podem ser distinguidas das demais espécies do gênero estudadas até o momento pela presença de uma fileira de nematocistos microbásicos mastigóforos do tipo A na umbrela, no nível do canal circular. Medusas adultas de C. cf. gracilis sp. 1 e C. cf. gracilis sp. 2 apresentam até 16 tentáculos e podem ser distinguidas entre si pelo diâmetro da umbrela: 6,6-10,1mm e 3,6-5,5mm, respectivamente. Quanto ao estágio de pólipo, C. cf. gracilis sp. 1 apresenta usualmente colônias dicotômicas eretas, hidrotecas alongadas, e gonotecas na hidrorriza e pedículos. Estes caracteres concordam com a descrição de C. gracilis, mas as espécies diferem entre si pela morfometria das gonotecas e dos nematocistos microbásicos mastigóforos do tipo B: aproximadamente 15mm de comprimento para C. gracilis e 9-10mm para C. cf. gracilis sp. 1. Por outro lado, nematocistos do tipo B de C. cf. gracilis sp. 2, com aproximadamente 14,5mm de comprimento, em média, são morfometricamente semelhantes aos de C. gracilis. No entanto, C. cf. gracilis sp. 2 difere de C. gracilis pela forma da hidroteca, por apresentar gonotecas apenas na hidrorriza, e pelo hábito polissifônico do colônias bem desenvolvidas. Uma terceira espécie, C. cf. gracilis sp. 3, é descrita com base em uma colônia sem gonângios. Aspectos da sistemática de Clytia são discutidos. / he life-cycles of Clytia linearis (Thornely, 1899) and two species with characters considered diagnostic of Clytia gracilis (M. Sars, 1850) – Clytia cf. gracilis sp. 1 and Clytia cf. gracilis sp. 2 – have been studied based on specimens collected in the shallow subtidal coast of São Sebastião and Ilhabela, southeast Brazil, between February 1999 and April 2000. Medusae were cultured in the laboratory (22-24oC). Colonies of C. linearis are monosiphonic, sympodial, up to 21.5mm high and bearing up to 26 hydranths and 10 gonangia. Adult medusae reached 2.5-3.6mm in diameter, and up to 29 tentacles and 28 statocysts. The presence of microbasic mastigophore type C nematocysts distinguishes adult medusae of C. linearis from other species of Clytia. A band of microbasic mastigophore type A nematocysts in the umbrella, at the level of the circular canal, distinguishes adult medusae of Clytia cf. gracilis spp. 1 and 2 from other species of the genus. Adult medusae of C. cf. gracilis sp. 1 and C. cf. gracilis sp. 2 have up to 16 tentacles, and can be distinguished by the diameter of the umbrella: 6.6-10.1mm and 3.6-5.5mm, respectively. Colonies of C. cf. gracilis sp. 1 are usually erect and dichotomous, the hydrothecae are elongated and the gonothecae present in the hydrorhiza and pedicels. These features closely match with the description of C. gracilis, but both species differ in the morphometry of the gonothecae and microbasic mastigophore type B nematocysts: about 15mm (length) for C. gracilis and 9-10mm for C. cf. gracilis sp. 1. Type B nematocysts of C. cf. gracilis sp. 2 (about 14.5mm in length) are more similar in size to those of C. gracilis. However, the former species differs from the latter in the shape of the hydrothecae, by having gonothecae only at the hydrorhiza and polysiphonic well-developed colonies. A third species, C. cf. gracilis sp. 3, is described based on an unfertile colony. Aspects of the systematics of Clytia are discussed.
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Effects of wood ash on freshwater organisms and aquatic forest ecosystems

Aronsson, K. Andreas January 2007 (has links)
Wood ash application (WAA) has been recommended mainly for two reasons; i) to avoid depletion of minerals in the soil due to whole tree harvest in the forestry and ii) to mitigate harmful effects of acidification of soil and surface waters. In conclusion, the effects on terrestrial ecosystems and, especially, tree growth, can be attributed to the properties of the ash, the dose applied and the specific site at which the ash is applied. The research conducted on the effects of WAA on limnological ecosystems is very limited, and the major purpose of the present thesis was to gain knowledge of the effects of wood ash to different freshwater organisms, and the more comprehensive, limnological effects of WAA in the first stream in Bispgården, Sweden. Effects of wood ash solutions on the unicellular alga Euglena gracilis Klebs, the amphipod Gammarus pulex L., and the moss Fontinalis antipyretica Hedw. were investigated under laboratory conditions. Common in all three species was the decline in performance (growth/velocity/respiration/oxygen evolution) when the concentration of wood ash exceeded 5 g/l and no adjustment of pH was done (alkaline solution). In contrast, different movement parameters (motility, upwards swimming and velocity) in E. gracilis (neutral conditions), and increased growth of F. antipyretica with increased concentrations of wood ash indicated that nutrients in the ash was bioavailable for these organisms. There was no evidence of toxic effects on the organisms from metals or other compounds as a result from exposure to wood ash solutions in the present studies. The field study was conducted in a forest area close to Bispgården, about 100 km NW from Sundsvall, Sweden. The catchment area (50 ha) of the stream Fanbergsbäcken was treated with wood ash in September of 2004 (3,000 kg/ha;selfhardened crush-ash). In general, both biological (diatoms) and chemical (pH, alkalinity, and aluminum (Al) measurements) indicators have shown no significant effect on acidification parameters from the addition of wood ash. There was, however, evidence of an increased pH during spring flood, accompanied with a decrease in the frequency of low pH values (<5.6) during spring flood. In addition to this, alkalinity was significantly higher in the period 2005-2006, compared to that of 2003. High concentrations of toxic forms of Al repeatedly occured in the stream Fanbergsbäcken, and the WAA did not affect the frequencies of high concentrations of toxic Al forms (<50 μg/l). Both the moss F. antipyretica and the leaves from Alnus incana displayed increased potassium (K) concentrations, although other nutrients did not increase from WAA. In conclusion, no evidence of WAA being effective in restoring or improving the ecological status of freshwater environments has been established, either in the literature or in the present field study. On the other hand, there were no indications of harmful effects due to WAA, either. However, we still do not know the effects of wood ash on several organisms (predominantly invertebrates) inhabiting small ponds and other, temporary or permanent, freshwater ecosystems. In the context of WAA, these environments and organisms have not attended any attention in the research published to date, and future studies are strongly encouraged.
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Avaliação biológica in vitro de espécies vegetais da Caatinga: Bauhinia cheilantha e Lippia gracilis / In vitro biological evaluation of the vegetal species of Caatinga: Bauhinia cheilantha and Lippia gracilis

Caffaro, Kátia Mayumi Takarabe 20 February 2014 (has links)
Medicinal plants have been growing in their social, cultural and economic importance in Brazil, which has the greatest biodiversity of the planet. Caatinga is the main ecosystem in the northeastern region and the only biome exclusively Brazilian. There is a great diversity of species popularly used for medicinal purposes in communities in the semiarid region of Alagoas. However, research proving their therapeutic efficacy is still insufficient. Ethanol extracts of two endemic species of the Caatinga, Bauhinia cheilantha (Bong.) Steud. and Lippia gracilis Schauer, known popularly as "mororó" and " alecrim-da-chapada", underwent in vitro assays to evaluate its antimicrobial and antioxidant potential, as well as identification of the class of its constituents through phytochemical screening. The bacterial strains Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Escherichia coli, Klebisiella pneumoniae, Pseudomonas aeruginosa and the fungal strain Candida albicans were used in the Agar diffusion method and broth microdilution, which determined the minimum inhibitory concentration (MIC) of extracts. For the evaluation of the scavenging capacity of antioxidants free radicals present in the extracts, the method of measuring the reduction of the synthetic radical 2,2- diphenyl - 1 - picryl - hidrazila (DPPH) was used. The results demonstrated the antioxidant potential of the leaves, stem bark and stem of B. cheilantha and antimicrobial potential of stem and aerial parts of the specie L. gracilis with MIC values comparatively lower than essential oils from other species of Lippia already studied. These findings can be attributed to the presence of flavonoids, tannins and steroids and flavonoids and terpenes, respectively, detected in phytochemical screening. Results support the popular use of B. cheilantha for the treatment of diabetes and L. gracilis for infectious processes, and provide direction for phytochemical studies to identify the constituents responsible for the verified biological activities. / As plantas medicinais vêm se destacando pela sua importância social, cultural e econômica no Brasil, o qual detém a maior biodiversidade do planeta. A Caatinga é o principal ecossistema da região Nordeste e o único bioma exclusivamente brasileiro. Há uma grande diversidade de espécies utilizadas popularmente de forma medicinal em comunidades do semiárido de Alagoas. No entanto, pesquisas que comprovem sua eficácia terapêutica são ainda incipientes. Extratos etanólicos de duas espécies endêmicas da Caatinga, Bauhinia cheilantha (Bong.) Steud. e Lippia gracilis Schauer, conhecidas popularmente como “mororó” e “alecrim-da-chapada”, foram submetidos à ensaios in vitro para avaliação de seu potencial antimicrobiano e antioxidante, além da identificação da classe dos constituintes através de prospecção fitoquímica. As cepas bacterianas Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, Escherichia coli, Klebisiella pneumoniae, Pseudomonas aeruginosa e a cepa fúngica Candida albicans foram utilizadas no método de difusão em Agar e na microdiluição em caldo, o qual determinou a concentração inibitória mínima (CIM) dos extratos. Para a avaliação da capacidade sequestradora de radicais livres por antioxidantes presentes nos extratos, foi utilizado o método de mensuração da redução do radical sintético 2,2-difenil-1-picril-hidrazila (DPPH). Os resultados demonstraram o potencial antioxidante das folhas, casca do caule e caule de B. cheilantha e o potencial antimicrobiano das partes aéreas e caule da espécie L. gracili, com valores de CIM menores que constituintes de óleos essenciais de outras espécies de Lippia já estudadas, em uma avaliação comparativa. Esses achados podem ser atribuídos à presença de flavonoides, taninos e esteroides e flavonoides e terpenos, respectivamente, evidenciados na prospecção fitoquímica realizada. Os resultados obtidos oferecem suporte ao uso popular de B. cheilantha para o tratamento do diabetes e L. gracilis para processos infecciosos, e fornecem direção para estudos fitoquímicos que identifiquem os constituintes responsáveis pelas atividades biológicas verificadas.

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