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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.
11

Estudo fitoquímico de Vernonia ferruginea: abordagens alelopáticas e metabolômicas / Phytochemical study of Vernonia ferruginea: alelopathic and metabolomic approaches

Amaral, Carita Liberato do [UNESP] 20 February 2017 (has links)
Submitted by CARITA LIBERATO DO AMARAL null (caritaliberato@gmail.com) on 2017-04-11T17:12:57Z No. of bitstreams: 2 Tese_Carita_Liberato_do_Amaral.pdf: 5356975 bytes, checksum: ea2885d6ecdf894dd43cb282fa498e09 (MD5) Tese_Carita_Liberato_do_Amaral.pdf: 5356975 bytes, checksum: ea2885d6ecdf894dd43cb282fa498e09 (MD5) / Rejected by Luiz Galeffi (luizgaleffi@gmail.com), reason: Solicitamos que realize uma nova submissão seguindo as orientações abaixo: Foram submetidos 2 arquivos PDF’s, apenas 1 arquivo deve ser submetido. O arquivo PDF não deve estar protegido e a dissertação/tese deve estar em um único arquivo, inclusive os apêndices e anexos, se houver. Corrija estas informações e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2017-04-17T19:13:40Z (GMT) / Submitted by CARITA LIBERATO DO AMARAL null (caritaliberato@gmail.com) on 2017-04-17T19:31:41Z No. of bitstreams: 1 Tese_Carita_Liberato_do_Amaral.pdf: 5356975 bytes, checksum: ea2885d6ecdf894dd43cb282fa498e09 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-04-17T19:42:22Z (GMT) No. of bitstreams: 1 amaral_cl_dr_jabo.pdf: 5356975 bytes, checksum: ea2885d6ecdf894dd43cb282fa498e09 (MD5) / Made available in DSpace on 2017-04-17T19:42:22Z (GMT). No. of bitstreams: 1 amaral_cl_dr_jabo.pdf: 5356975 bytes, checksum: ea2885d6ecdf894dd43cb282fa498e09 (MD5) Previous issue date: 2017-02-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / As condições ambientais, assim como o contraste sazonal nas fitofisionomias do Cerrado entre a época seca e úmida colaboram para a diversificada sintetize e seleção de metabólitos secundários em plantas. Os metabólitos secundários atuam como uma interface química entre plantas e o meio, desta forma a sua síntese pode ser comumente alterada pelas condições ambientais. Fatores como temperatura, disponibilidade hídrica, luminosidade, características do solo, nutrientes e poluição atuam diretamente sobre a produção e liberação desses compostos. Os microrganismos do solo podem transformar os compostos tóxicos liberados, desativando-os ou dando origem a compostos ainda mais tóxicos, assim como esses compostos podem alterar as características e atributos do solo quando presentes em quantidades adequadas. Dentre as plantas nativas do Cerrado destaca-se a espécie Vernonia ferruginea, uma agressiva infestante de pastagem, que possui indícios de produção de compostos com potencial tóxico. Desta forma, esta pesquisa foi desenvolvida para verificar a atividade tóxica de V. ferruginea e se a mudança de algumas características como disponibilidade hídrica, tipo de solo, condições de luminosidade e concentração de alumínio no solo influenciam a produção desses compostos. Para tal, plantas de V. ferruginea foram desenvolvidas sobre diferentes condições para posterior extração e/ou fracionamento do material vegetal para verificação de atividade biológica por meio de bioensaios e identificação de grupos químicos. Considerando os resultados dos parâmetros de germinabilidade e de desenvolvimento das espécies testadas é possível indagar sobre a possibilidade de V. ferruginea ter a capacidade de liberar substâncias tóxicas, uma vez que, consequências diretas da presença desses compostos nos extratos foram verificadas no bioensaio, como: a inibição/redução da germinação de sementes, injúria ou necrose no sistema radicular e redução do desenvolvimento e do acúmulo de massa seca das plântulas. Os resultados também dão base para constatar que algumas interações da espécie com as alterações nas suas condições de desenvolvimento causam desvios de rotas biossintética de metabólitos modificando e/ou potencializando sua capacidade fitotóxico. / The environmental conditions, as well as the seasonal contrast in the Cerrado phytophysiognomies between the dry and wet seasons, contribute to the diversified synthesis and selection of secondary metabolites in plants. Secondary metabolites act as a chemical interface between plants and the environment, so their synthesis can be commonly altered by environmental conditions. Factors such as temperature, water availability, luminosity, soil characteristics, nutrients and pollution act directly on the production and release of these compounds. Soil microorganisms can transform the released toxic compounds, deactivating them or giving rise to even more toxic compounds, as these compounds can alter the characteristics and attributes of the soil when present in adequate amounts. Among the native plants of the Cerrado, the species Vernonia ferruginea, an aggressive pasture weed, stands out, with indications of production of compounds with toxic potential. Thus, this research was developed to verify the toxic activity of V. ferruginea and if the change of some characteristics such as water availability, soil type, light conditions and aluminum concentration in the soil influence the production of these compounds. For this, plants of V. ferruginea were developed on different conditions for later extraction and / or fractionation of the vegetal material for verification of biological activity by means of bioassays and identification of chemical groups. Considering the results of the parameters of germinability and development of the tested species it is possible to inquire about the possibility of V. ferruginea being able to release toxic substances, since direct consequences of the presence of these compounds in the extracts were verified in the bioassay, such as: The inhibition / reduction of seed germination, injury or necrosis in the root system and reduction of the development and accumulation of dry mass of the seedlings. The results also provide evidence that some interactions of the species with changes in their developmental conditions cause biosynthetic pathway deviations of metabolites modifying and / or potentiating their phytotoxic capacity. / FAPESP: 12/25298-0
12

Níveis de congêneres, carbamata de etila e outros contaminantes em vodcas e cachaças de consumo popular no Brasil

PEREIRA, Elainy Virginia dos Santos 29 February 2012 (has links)
Submitted by (edna.saturno@ufrpe.br) on 2016-07-26T13:23:51Z No. of bitstreams: 1 Elainy Virginia dos Santos Pereira.pdf: 331613 bytes, checksum: fd1ce032c90754e480ff37f32d701a3e (MD5) / Made available in DSpace on 2016-07-26T13:23:51Z (GMT). No. of bitstreams: 1 Elainy Virginia dos Santos Pereira.pdf: 331613 bytes, checksum: fd1ce032c90754e480ff37f32d701a3e (MD5) Previous issue date: 2012-02-29 / Ethyl carbamate (EC, C2H5OCONH2) or urethane is a known carcinogen and genotoxic substance that occurs in various fermented foods, in particular spirits. In 2005, after several studies had shown that cachaça, the most consumed spirit in Brazil, was heavily contaminated with EC, the Brazilian Ministry of Agriculture, Livestock and Food Supply (MAPA) established an EC limit (150 μg.L-1) for the beverage (to come into effect in June 2012), but other consumed spirits in Brazil, such as vodka, were not subjected to any EC control. Given the lack of information on EC levels and chemical profiles of Brazilian vodkas, along with the effects of new EC regulation for cachaça, the objective of this study was to determine the levels of congeners (volatile acidity, aldehydes, esters, higher alcohols and furfural), EC and other contaminants (methanol, copper, lead and arsenic) in vodkas and cachaças produced in Brazil. Twenty three brands of “industrial” cachaças (i.e. cachaças produced on a large scale and distilled in columns) and twenty one brands of vodkas were sampled. The brands were low-priced (below US$11.00 per 600-1000 mL bottle) and recorded (licit). All sampled cachaças and vodkas complied with MAPA regulation for alcoholic strength, volatile acidity, methanol, aldehydes, esters, higher alcohols, furfural, total congeners, copper, lead and arsenic. EC levels in cachaça ranged from 10 μg.L-1 (limit of detection, LD) to 713 μg.L-1, average 245 μg.L-1, with 15 brands (65 %) exceeding 150 μg.L-1. EC levels in all sampled vodkas were below the LD. The vodka results are probably related to its distillation process, in particular the use of extractive and rectification columns (column rectification system), which allow production of high strength spirits with very low levels of congeners. This is not the case usually found in “industrial” cachaça plants, where a smaller single distillation column, with fewer trays, is used. This cachaça distillation system does not seem to promote the same efficiency in congeners reduction, especially for highly volatile “head” products (including cyanide, precursor of EC), when compared to the column rectification system used in vodka. / Carbamato de etila (CE, C2H5OCONH2) ou uretana é uma substância reconhecidamente genotóxica e carcinógena que ocorre em vários alimentos fermentados, em especial, bebidas alcoólicas destiladas. Em 2005, após constatação que a cachaça, a bebida alcoólica destilada mais consumida no Brasil, possuía elevado nível deste contaminante, o Ministério da Agricultura, Pecuária e Abastecimento (MAPA) estabeleceu uma tolerância de 150 μg de CE por litro de cachaça (a entrar em vigor em junho de 2012), porém outras bebidas destiladas de consumo popular, tal como a vodca, ficaram livres deste controle. Assim, diante do desconhecimento do perfil químico e do nível de CE nas vodcas brasileiras, aliada a iminência da entrada em vigor do limite de CE para cachaça, este trabalho teve como objetivo determinar os níveis de congêneres (acidez volátil, aldeídos, ésteres, alcoóis superiores e furfural), CE e outros contaminantes (metanol, cobre, chumbo e arsênio) em cachaças e vodcas produzidas no Brasil. Foram amostradas 23 marcas de cachaça do tipo “industrial” (produzidas em larga escala e destiladas em coluna) e 21 marcas de vodca, todas de consumo “popular”, definidas neste trabalho com base no preço (até R$20,00 por embalagem de 600 a 1000 mL). Tomando como referência a legislação vigente, observou-se que as cachaças e vodcas analisadas apresentaram adequação quanto aos níveis de etanol, acidez volátil, metanol, aldeídos, ésteres, alcoóis superiores, furfural, somatório de congêneres, cobre, chumbo e arsênio. Os níveis de CE encontrados nas 23 marcas de cachaça variaram entre 10 μg.L-1 (limite de detecção do método, LD) e 713 μg.L-1, com média de 245 μg.L-1, sendo que 15 (65%) apresentaram concentrações acima do limite tolerado pelo MAPA. Quanto ao nível de CE nas vodcas, todas apresentaram valores abaixo do LD. Os resultados observados nas vodcas podem ser atribuídos ao processo de destilo-retificação da bebida, em especial o emprego de colunas depuradora, destiladora e retificadora, as quais possibilitam atingir altas concentrações de etanol e níveis muito baixos de congêneres. Esse não é o caso encontrado nas destilarias de cachaças “industriais”, as quais comumente empregam destilação em coluna de baixo grau, com menor número de pratos, processo que não apresenta a mesma capacidade de redução de congêneres, notadamente dos proodutos de “cabeça” (entre eles o cianeto, precursor do CE), quando comparado a uma destiloretificação.
13

Benefit of including bioactive legumes (sainfoin, red clover) in grass-based silages on ruminant production and pollutant emissions / Inclusion de légumineuses bioactives (sainfoin, trèfle violet) dans les ensilages à base d'herbe : bénéfices pour la production des ruminants et les rejets polluants

Copani, Giuseppe 10 September 2015 (has links)
Les légumineuses permettent de réduire les intrants en élevage (engrais, concentrés) en raison notamment de leurs niveaux élevés en protéines. Cependant, à la fois pendant le processus d'ensilage et celui de fermentation dans le rumen, les protéines peuvent subir une importante dégradation, ce qui affecte la valeur nutritive des fourrages et induit des rejets d'azote (N) importants, notamment dans l'urine. Certaines légumineuses peuvent alors être d'un intérêt particulier car elles produisent des composés secondaires qui peuvent modifier positivement les processus fermentaires et digestifs. Ainsi, les tannins condensés (CT) présents dans le sainfoin (SF, Onobrychis viciifolia) sont capables de se lier aux protéines, réduisant leur dégradation dans le silo et le rumen et se traduisant par un transfert de l'excrétion d'azote de l'urine vers les fèces. Le trèfle violet (RC, Trifolium pratense) contient la polyphénoloxydase (PPO), une enzyme qui catalyse l'oxydation de différents composés phénoliques en quinones. Comme les CTs, les quinones sont capables de former des complexes avec les protéines permettant de réduire leur dégradation dans le silo et le rumen. L'objectif de cette thèse était alors d'étudier et de quantifier les bénéfices potentiels de l'utilisation de ces deux espèces de légumineuses bioactives sur i) la qualité et la conservation des ensilages, ii) la fermentation ruminale, l'efficacité digestive et les performances des ovins, et iii) l'empreinte environnementale (excrétion d'N et de CH4). Nous avons effectué deux essais in vitro et deux essais in vivo, basés sur des ensilages composés de ces deux légumineuses, seules ou en mélange avec une graminée (la fléole- T, Phleum pratense L.) qui nous a servie de contrôle. Les essais in vitro nous ont permis de nous focaliser sur la qualité et la conservation des ensilages ainsi que sur la fermentation ruminale, tandis que les essais in vivo se sont concentrés sur la performance et l'efficacité digestive des agneaux, ainsi que sur leur bilan azoté et leurs émissions de CH4. L'inclusion de légumineuses bioactives dans les ensilages d'herbe a amélioré la qualité du fourrage, la fermentation pendant le processus d'ensilage ainsi que la protection des protéines contre une dégradation au sein du silo et du rumen. Globalement, l'alimentation des agneaux avec des mélanges comportant ces légumineuses s'est traduite par une augmentation de l'ingestion de matière sèche, en comparaison des agneaux alimentés avec la graminée pure. Néanmoins, en raison de la digestibilité nettement plus faible de T-SF, probablement due à une composition et une nature des fibres différentes ainsi qu'à la présence de CT, les agneaux ayant reçu T-SF ont montré une ingestion et des performances plus faibles que ceux ayant reçu les ensilages contenant RC. Dans le rumen, il semble que les protéines de RC aient été plus protégées de la dégradation que celles de SF, tandis que dans la suite du tractus digestif, les complexes formés entre protéines et CT (avec SF) se seraient moins dissociés que ceux formés entre protéines et quinones (avec RC), ce qui pourrait en partie expliquer le transfert d'excrétion de l'N de l'urine vers les fèces, observé chez les agneaux alimentés avec T-SF et bénéfique pour l'environnement. SF a également permis de réduire légèrement les émissions de CH4. Ainsi, utiliser des légumineuses bioactives dans les pratiques d'alimentation des ruminants apparaît une stratégie prometteuse pour fournir des produits animaux de façon plus durable. Nos résultats montrent que chaque espèce apporte des avantages différents, plutôt orientés vers la qualité de l'aliment et les performances animales pour RC mais plutôt orientés vers la réduction des rejets pour SF. Des recherches complémentaires sont donc nécessaires pour mieux caractériser ces avantages et élargir les investigations à d'autres espèces, d'autres mélanges et d'autres bénéfices potentiels. (...) / Fodder legume species allow to reduce inputs in livestock breeding systems (fertilizer, concentrates) notably because they contain high levels of crude proteins which are of primary importance in ruminant nutrition. However, during both silage and rumen fermentation processes, proteins are submitted to degradation which affects forage nutritive value and leads to nitrogen (N) losses notably via urine. Some specific legumes can then be of particular interest as they produce plant secondary compounds that can positively affect silage and digestive processes. Condensed tannins (CTs) present in sainfoin (SF, Onobrychis viciifolia) are able to bind with proteins thereby reducing their degradation in the silo and the rumen, resulting in a shift in N excretion from urine to faeces. Red clover (RC, Trifolium pratense) contains polyphenol oxidase (PPO), an enzyme that catalyses the oxidation of different phenolics into quinones. As CTs, quinones are able to form complexes with proteins that will similarly reduce their degradation in the silo and the rumen. The aim of this thesis was to investigate and quantify the potential benefits of using these two bioactive legume species on i) quality and conservation of silages, ii) rumen fermentation, digestive efficiency and sheep performance, and iii) environmental footprint (N excretion and CH4 emissions). We conducted two in vitro and two in vivo trials which were based on silages of pure legumes or of different mixtures with the grass species (timothy T, Phleum pratense L.), which served as control. In the in vitro trials, we focussed on silage quality, silage conservation and rumen fermentation, while in the in vivo trials, we focussed on lambs' performance, digestion efficiency, N balance and CH4 emissions. Including bioactive legumes in mixtures with grass improved, compared to pure grass, forage quality and fermentation during the silage making process, as well as proteins' protection from degradation within both the silos and the rumen. Lambs fed with the mixtures involving legumes responded with an increase in DM intake compared to their counterparts fed with T. Nevertheless, due to a possibly different fibre composition and to the presence of CT which impaired SF digestibility, lambs that consumed T-SF showed lower intake and performance than those that received RC-containing silages. In the rumen, RC proteins appeared more protected from degradation than SF ones, while in the subsequent parts of the digestive tract, the proteins-CT complexes (from SF) might less dissociate than the proteins-quinones ones (from RC). This could partly explain the environment-friendly shift in N excretion from urine to faeces when animals are fed with T-SF. SF also allowed to slightly reduce CH4 emissions. Thus, utilizing bioactive legumes in livestock feeding practices is a promising strategy to produce animal products more sustainably. Our results show different benefits relative to the bioactive legume species involved, directed towards boosted forage quality and animals' performance for RC but towards lowered wastes for SF. Further research is thus needed to better characterize these benefits and enlarging investigations to other plant species, mixtures and potential benefits (e.g. health). This will help to determine the appropriate choice of plant species according to the objectives.
14

Atividade de enzimas do metabolismo de compostos secundários comprometidos com o enraizamento \"in vitro\" de Eucalyptus grandis HILL ex MAIDEN / Enzyme activity of metabolism of secondary compounds related to in vitro rooting of Eucalyptus grandis HILL ex MAIDEN

Isaac Stringueta Machado 18 November 1993 (has links)
O trabalho realizado constitui uma estratégia em Biotecnologia de Plantas para a investigação dos esquemas bioquímicos controladores da diferenciação celular no processo de enraizamento. Através da técnica da cultura de tecidos \"in vitro\" foram micropropagados clones de Eucalyptus grandis HILL ex MAIDEN (GO 250, GO 682 e GO 669) selecionadas no CEBTEC/USP. Em uma pesquisa preliminar foram estabelecidas e multiplicadas gemas, seguida de testes da composição de meios de cultura para elongação e enraizamento. Foram estudadas diversas possibilidades de balanceamento das substâncias reguladoras de crescimento - ácido indolilbutírico (AIB)/ benzilaminopurina (BAP). Os clones apresentaram comportamentos anatômico-fisiológicos (massa fresca e seca; teor protéico; taxas de multiplicação das brotações epicórmicas, elongação e enraizamento) diferenciados entre si. As frequências de enraizamento mostraram-se superiores às já observadas por outros autores. Foram estabelecidas, ainda, algumas alterações na composição dos meios de cultura empregados. Através de experimentos cinéticos foram determinados os padrões de indução e/ou inibição das enzimas fenilalanina amônia-liase (PAL) e glucose 6-fosfato-desidrogenase (G-6P-DH) importantes para a biossíntese de compostos flavonóides, considerados como os principais cofatores das auxinas endógenas no complexo iniciador do enraizamento. Verificou-se que embora o suprimento exógeno crescente de AIB tenha resultado em maiores taxas de enraizamento, as atividades da PAL e G-6P-DH não se mostraram significativamente alteradas. Contudo, foi observado também que as gemas que enraizaram apresentaram atividade da PAL significativamente superior, evidenciando maior fluxo do Metabolismo do Fenilpropano durante o enraizamento. / This study constitutes a strategy in Plant Biotechnology with the purpose to investigate the regulating biochemical development of the cellular differentiation in the rooting process. Through plant tissue culture \"in vitro\" technique, clones of Eucalyptus grandis Hill ex Maiden (GO 250, GO 682 e GO 669) selected at CEBTEC/USP, were micropropagated. In a preliminary study shoots were multiplied, followed by tests of media culture composition for shoot elongation and root initiation. Several possibilities and rates of plant growth regulators, indolilbutyric acid (IBA)/benzylaminopurine (BAP) were studied. The clones showed different anatomic-physiological behaviours (fresh and oven-dry weight; proteic content; epicormic shoots multiplication rates, elongation and rooting). The frequences of rooting were higher than those described by other authors. Some modifications in the composition of used cuIture media were also defined. Through kinetic experiments, induction and inhibition patterns of phenylalanine ammonia-lyase (PAL) and glucose 6- phosphate-dehydrogenase (G-6P-DH) important to the biossyntesis of flavonoid compounds were determined. They were considered as the main cofactors of endogenous auxins in the root stimulating complex. Although, the increasing exogenous supply of AIB resulted in higher rooting rates, the activities of PAl and G-6P-DH enzyme did not present alterations. However, it was also observed that shoots wich rooted, in the treatments, showed higher PAL activity. resulting in higher flux of phenylpropanoid metabolism during the rooting.

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