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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

Avaliação da bioatividade e estudo da composição química do óleo essencial das folhas de zanthoxylum tingoassuiba A. St. Hil

Nogueira, Jeane Andréia Pedrosa 24 March 2017 (has links)
Submitted by Biblioteca da Faculdade de Farmácia (bff@ndc.uff.br) on 2017-03-24T17:59:19Z No. of bitstreams: 1 Nogueira, Jeane Andréia Pedrosa [Dissertação, 2014].pdf: 2106117 bytes, checksum: bb81f3982408282eb8ff2fb4a80af31f (MD5) / Made available in DSpace on 2017-03-24T17:59:19Z (GMT). No. of bitstreams: 1 Nogueira, Jeane Andréia Pedrosa [Dissertação, 2014].pdf: 2106117 bytes, checksum: bb81f3982408282eb8ff2fb4a80af31f (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Zanthoxylum tingoassuiba é uma espécie da família Rutaceae, popularmente conhecida como guando-do-mato, mamica-de-porca e limãozinho. Este trabalho descreve a análise da composição química do óleo essencial das folhas, sendo silvestreno identificado como constituinte majoritário através da análise por CG/EM. É a primeira vez que os constituintes muurola-4,5-trans-dieno e isodauceno são identificados no óleo essencial desta espécie. Para a atividade inseticida do óleo essencial desta espécie frente ao inseto Rhodnius prolixus, um dos vetores da doença de Chagas, foi observada alta taxa de mortalidade, mal formação e paralisia em ninfas de quinto estádio deste inseto. A atividade inseticida foi também avaliada frente aos fitófagos Dysdercus peruvianus e Oncopeltus fasciatus, insetos praga de lavoura. Em Dysdercus peruvianus o processo de metamorfose e período intermuda foram afetados e ocorreram deformações em alguns insetos tratados, além de mostrar uma alta taxa de mortalidade. Nos insetos Oncopeltus fasciatus, o tratamento com óleo puro e nas diluições de 500 mg/mL e 250mg/mL apresentou mortalidade de 100%. Na avaliação da atividade acaricida, ocorreu alteração na oviposição, diminuição da eclodibilidade dos ovos e 100% de mortalidade na concentração de 5%, além de mostrar que a eficácia do óleo essencial é dose dependente. Estes resultados sugerem que o óleo essencial das folhas de Z. tingoassuiba pode futuramente ser utilizado como ativo em formulações bioacaricidas, fazendo parte da terapêutica do carrapato do boi, um bioagente responsável por causar enormes danos a pecuária. Neste trabalho é relatado às atividades inseticida e carrapaticida para Zanthoxylum tingoassuiba, demonstrando que esta espécie possui um potencial biotecnológico a ser mais estudado / Zanthoxylum tingoassuiba is a species from the Rutaceae family, commonly known as “guando-do-mato”, “mamica - de - porca” e “limãozinho”. This work describes the analysis of the essential chemical composition of its leaves oil having identified the sylvestrene as a major component, through CGMS analysis. It is the first time that constituents muurola - trans - 4,5 - diene and isodaucene are identified in an essential oil from this species. It was observed, for insecticidal activity of the essential oil against the insect Rhodnius prolixus, one of the vectors of Chagas disease, a high mortality rate, malformation and paralysis in fifth instar nymphs. It was also evaluated against phytophagous Oncopeltus fasciatus and Dysdercus peruvianus, that are insects pests of crops. In Dysdercus peruvianus the process of metamorphosis and intermolt period were affected, some of the treated insects presented malformation and a high mortality rate. In Oncopeltus fasciatus, the treatment with pure oil and dilutions of 250.00mg/mL and 500.00mg/mL presented 100% mortality rate. In the acaricidal activity evaluation, changes occurred in oviposition, decreased hatchability of eggs and 100 % mortality at a concentration of 5 %. It also shows that the effectiveness of the essential oil is dose dependent. These results suggests that the essential oil from leaves Z. tingoassuiba can be used as actives in bioacaricidal formulations in the future, being part of the cattle tick therapeutics, a bioagent that causes huge damage to livestock. This work reports the insecticidal and acaricidal activities for Zanthoxylum tingoassuiba, showing that the species has a biotechnological potential for further studies
52

Socio-economic aspects of the sustainable harvesting of buchu (Agathosma Betulina) with particular emphasis on the Elandskloof community

Williams, Samantha January 2005 (has links)
Magister Artium - MA / The aim of this thesis is to explore the socio-economic factors that impact on the sustainable harvesting of buchu in the Western Cape of South Africa. Some of the factors that will be explored include poverty, natural resource tenure, legislation, and local practices with regard to the harvesting of buchu. In order to achieve the objectives of the study, which include documenting different local livelihoods, establishing the roles played by the harvesting of wild buchu within these livelihoods, and analyzing perceptions of different stakeholders regarding sustainable harvesting of buchu, the study employed two approaches. The first was a review of the literature, and the second, empirical research in the form of a case study (the communal land owners of Elandskloof, Western Cape) was utilized. Agathosma betulina, one type of buchu and cited as the best type of buchu, has gained popularity as there is a demand for plant material both locally and internationally. This demand has created some concerns for wild populations of buchu as much of the industry is still supplied by populations harvested from the wild. Cultivation of buchu has emerged as a possible pressure lifter to the wild populations, as a poverty reduction strategy (as rural people are also cultivating), and as a way to provide for some of the demand experienced in the market. The buchu industry is a very lucrative one and, therefore, many problems are being identified and experienced. Noting this, the study makes two broad arguments. Firstly, even though the buchu trade is dynamic and fraught with many difficulties, it is a trade that can benefit all stakeholders and, consequently, there is a need for new legislation or a review of the current legislation guiding the industry. Better monitoring and evaluating processes, as well as information and communication platforms where stakeholders can interact, prove important. Hence, this should include the participation from stakeholders at all levels. Secondly, in order to establish effective policy guidelines, an understanding of the social dynamics that influences buchu harvesting is important for the resource sustainability as well as the trade. / South Africa
53

Flavanone 3-Hydroxylase Expression in Citrus Paradisi and Petunia Hybrida Seedlings

Pelt, Jennifer L., Downes, W. Andrew, Schoborg, Robert V., McIntosh, Cecilia A. 01 January 2003 (has links)
Petunia hybrida and Citrus paradisi have significantly different flavonoid accumulation patterns. Petunia sp. tend to accumulate flavonol glycosides and anthocyanins while Citrus paradisi is known for its accumulation of flavanone diglycosides. One possible point of regulation of flavanone metabolism is flavanone 3-hydroxylase (F3H) expression. To test whether this is a key factor in the different flavanone usage by Petunia hybrida and Citrus paradisi, F3H mRNA expression in seedlings of different developmental stages was measured using semi-quantitative RT-PCR. Primers were designed to conserved regions of F3H and used to amplify an approximately 350 bp segment for quantitation by PhosphorImaging. Primary leaves of 32 day old grapefruit seedlings and a grapefruit flower bud had the highest levels of F3H mRNA expression. Petunia seedlings had much lower levels of F3H mRNA expression relative to grapefruit. The highest expression in petunia was in primary leaves and roots of 65 day old seedlings. These results indicate that preferential use of naringenin for production of high levels of flavanone glycosides in young grapefruit leaves cannot be attributed to decreased F3H mRNA expression.
54

Secondary Product Glucosyltransferase and Putative Glucosyltransferase Expression During Citrus paradisi (c.v. Duncan) Growth and Development

Daniel, Jala J., Owens, Daniel K., McIntosh, Cecilia A. 10 October 2011 (has links)
Flavonoids are secondary metabolites that have significant roles in plant defense and human nutrition. Glucosyltransferases (GTs) catalyze the transfer of sugars from high energy sugar donors to other substrates. Several different secondary product GTs exist in the tissues of grapefruit making it a model plant for studying their structure and function. The goal of this investigation was to determine the expression patterns of seven putative secondary product GTs during grapefruit growth and development by quantifying mRNA expression levels in the roots, stems, leaves, flowers, and mature fruit to establish whether the genes are expressed constitutively or if one or more could be expressed in a tissue specific manner and/or developmentally regulated. Six growth stages were defined from which RNA was extracted, and expression levels were quantified by standardized densitometry of gene-specific RT-PCR products. Results show that there were variable degrees of PGT expression in different tissues and at different developmental stages. These results add to the growing knowledge base of dynamics of expression and potential regulation of secondary metabolism in Citrus paradisi.
55

Identification, Recombinant Expression, and Biochemical Characterization of a Flavonol 3-O-Glucosyltransferase Clone From Citrus Paradisi

Owens, Daniel K., McIntosh, Cecilia A. 01 July 2009 (has links)
Glucosylation is a predominant flavonoid modification reaction affecting the solubility, stability, and subsequent bioavailability of these metabolites. Flavonoid glycosides affect taste characteristics in citrus making the associated glucosyltransferases particularly interesting targets for biotechnology applications in these species. In this work, a Citrus paradisi glucosyltransferase gene was identified, cloned, and introduced into the pET recombinant protein expression system utilizing primers designed against a predicted flavonoid glucosyltransferase gene (AY519364) from Citrus sinensis. The encoded C. paradisi protein is 51.2 kDa with a predicted pI of 6.27 and is 96% identical to the C. sinensis homologue. A number of compounds from various flavonoid subclasses were tested, and the enzyme glucosylated only the flavonol aglycones quercetin (Kmapp = 67 μ M; Vmax = 20.45 pKat/μg), kaempferol (Kmapp = 12 μ M; Vmax = 11.63 pKat/μg), and myricetin (Kmapp = 33 μ M; Vmax = 12.21 pKat/μg) but did not glucosylate the anthocyanidin, cyanidin. Glucosylation occurred at the 3 hydroxyl position as confirmed by HPLC and TLC analyses with certified reference compounds. The optimum pH was 7.5 with a pronounced buffer effect noted for reactions performed in Tris-HCl buffer. The enzyme was inhibited by Cu2+, Fe2+, and Zn2+ as well as UDP (Kiapp = 69.5 μ M), which is a product of the reaction. Treatment of the enzyme with a variety of amino acid modifying compounds suggests that cysteine, histidine, arginine, tryptophan, and tyrosine residues are important for activity. The thorough characterization of this C. paradisi flavonol 3-O-glucosyltransferase adds to the growing base of glucosyltransferase knowledge, and will be used to further investigate structure-function relationships.
56

Evolution of Melicope J.R.Forst & G.Forst (Rutaceae), the largest adaptive radiation of woody plants on the Hawaiian Islands.

Pätzold, Claudia 18 February 2020 (has links)
No description available.
57

Socio-economic aspects of the sustainable harvesting of buchu (Agathosma Betulina) with particular emphasis on the Elandskloof community

Williams, Samantha January 2005 (has links)
The aim of this thesis was to explore the socio-economic factors that impact on the sustainable harvesting of buchu in the Western Cape of South Africa. Some of the factors that were explored include poverty, natural resource tenure, legislation, and local practices with regard to the harvesting of buchu.
58

Historia local de naranja amarga (<i>Citrus × Aurantium</i> L., Rutaceae) del viejo mundo asilvestrada en el corredor de las antiguas misiones jesuíticas de la provincia de Misiones (Argentina)

Stampella, Pablo César January 2015 (has links)
Los cítricos son frutales exóticos en América, introducidos a lo largo de cinco siglos a partir del contacto entre ambos hemisferios, que han sido apropiados y resignificados por comunidades locales y pueblos originarios. Los mismos se han constituido en cultivos de gran importancia, reconociéndose asimismo poblaciones espontáneas en varios enclaves de Argentina, generalmente asociados a ambientes boscosos o selváticos. El objetivo general de esta tesis es diseñar los procesos locales de selección cultural en poblaciones de cítricos introducidas en el área de las Misiones Jesuíticas y aportar al concepto de domesticación. Para ello se parte de las siguientes premisas: A- se considera la domesticación en un sentido amplio, no sólo como modificaciones morfofisiológicas que adaptan la planta a un determinado ambiente sino también como proceso, una extensión de la unidad doméstica hacia el paisaje, resultando en la domesticación del mismo; B- la noción de paisaje como ambiente interpretado, sobre el cual se llevan a cabo prácticas inherentes a diferentes aspectos culturales de quienes lo habitan; prácticas cuyo efecto no necesariamente es negativo o destructivo. Este caso de estudio es abordado mediante distintas metodologías articuladas entre sí, característica del enfoque interdisciplinario. La metodología etnobotánica histórica y la etnohistórica fueron empleadas para el análisis de los documentos históricos relativos a las variedades de cítricos ingresadas, procedencias y rutas de ingreso, como también para el relevamiento de los distintos espacios productivos de la época de las misiones jesuíticas (Siglos XVII-XVIII). Mediante las metodologías etnobotánica y etnoecológica se relevó la diversidad actual, la percepción de la variabilidad, los usos locales, los microambientes donde se encuentran y las prácticas de manejo sobre las plantas y los microambientes. También se relevaron los usos medicinales de los cítricos asociados a enclaves cercanos a Paraguay y Brasil (cuencas del Paraná y Uruguay, respectivamente) y las variaciones de acuerdo a la situación en el gradiente de urbanización/ruralidad. La metodología botánica fue empleada para la identificación de las plantas involucradas y análisis morfológico-organoléptico de la variabilidad de acuerdo a las prácticas de manejo sobre el entorno. Se relevaron las variedades históricas ingresadas tempranamente a partir del siglo XVI, las posibles procedencias, rutas de ingreso y otros aspectos referidos a su “naturalización” y cultivo en las Misiones jesuíticas. Las menciones generales de estas variedades fueron acompañadas con las obras de Tratados de Cítricos (o Hespérides) de los siglos XVI a XIX, abundantes en detalles que ejemplificaron la diversidad pasada. Mediante el trabajo de campo en el sur de Misiones (Argentina) se ha relevado una alta diversidad de etnovariedades (30) cultivadas y espontáneas, estructuradas en 9 etnoespecies, algunas de ellas de introducción histórica y otras más recientes, con variados usos asignados. Asimismo, se relevaron 7 microambientes definidos por la presencia de las etnoespecies con diferentes intensidades en las prácticas de manejo. Las prácticas relevadas fueron dirigidas principalmente a los microambientes antes que a los cítricos en sí. La variabilidad de usos medicinales y la importancia de las etnoespecies, analizadas de acuerdo a su distribución en la cuenca del Paraná y del Uruguay, y a la situación en el gradiente de urbanización/ruralidad, mostró diferencias de importancia en algunas etnoespecies y propiedades medicinales. También, la percepción de la variabilidad del género, que resulta en esquemas de clasificaciones locales complejos, indican una fuerte relación con las comunidades locales estudiadas. Se discuten los procesos de generación de variabilidad sobre este género y sobre el paisaje, de acuerdo a los mecanismos de variabilidad genética intrínsecos del género, la historia de introducción y las prácticas sobre las plantas y los microambientes que resultan en la domesticación del paisaje. Este enfoque ecológico-histórico aporta asimismo en la discusión de la terminología de uso corriente como “naturalización” o “asilvestramiento” proponiéndose, en cambio, el término antropización de las plantas que acompañan el avance de la unidad doméstica sobre el ambiente. Todo esto lleva a percibir los paisajes como selvas antropogénicas, antes que ambientes prístinos, y por ello, susceptibles de estrategias de conservación in situ o biocultural que engloben a las comunidades locales, la diversidad de paisajes, las etnoespecies y las prácticas asociadas a las mismas. El enfoque interdisciplinario empleado permitió caracterizar la diversidad actual y las introducciones históricas, como también identificar prácticas de manejo sustentables y generadoras de variabilidad a distintos niveles. Estos frutales exóticos constituyen elementos identitarios que contribuyen a la definición de las comunidades y escenarios cotidianos. La decisión de incorporar elementos exóticos debe entenderse en el marco de las cosmovisiones de estos grupos nativos. Por lo tanto, estas plantas de introducción relativamente reciente, y con registro escrito, permiten al investigador comprender y diseñar la domesticación del paisaje como proceso multidimensional del entorno físico social y simbólico. / Tesis dirigida por María Lelia Pochettino y Norma Inés Hilgert.
59

Socio-economic aspects of the sustainable harvesting of buchu (Agathosma Betulina) with particular emphasis on the Elandskloof community

Williams, Samantha January 2005 (has links)
The aim of this thesis was to explore the socio-economic factors that impact on the sustainable harvesting of buchu in the Western Cape of South Africa. Some of the factors that were explored include poverty, natural resource tenure, legislation, and local practices with regard to the harvesting of buchu.
60

Fitoquímica, quimiossistemática e busca de novos fármacos antichagásicos e antileishmanioses: estudo de Raputia praetermissa (Rutaceae). / Phytochemistry, chemosystematic and searching of new antichagasic and antileishmaniasis drugs: study of Raputia praetermissa (Rutaceae).

Rosas, Lisandra Vieira 31 August 2005 (has links)
Made available in DSpace on 2016-06-02T20:34:03Z (GMT). No. of bitstreams: 1 TeseLVR.pdf: 6988214 bytes, checksum: d780cb227a0bf1454902b195e898d753 (MD5) Previous issue date: 2005-08-31 / Universidade Federal de Minas Gerais / Raputia praetermissa (Engler) Emmerich is a tree found only in the Forest Reserve Adolpho Ducke, Amazonas, Brazil. The genus Raputia was originally described by Engler and many species were included in this genus, but in 1978, Emmerich proposed three new genera Neoraputia, Raputiarana e Sigmathantus in order to accommodate six species, four belonging to the genus Raputia, which is assigned into the tribe Cuspariae, and two that had not been described yet. From our knowledge no previous phytochemical work has been reported on Raputia. Therefore, this study describes phytochemical and chemosystematic investigation and the search of compounds with trypanocidal and leishmanicidal activity from roots of R. praetermissa. The phytochemical work involved crude extract preparation, followed by fractionation and isolation of compounds thorough different chromatography methods. Spectroscopic analyses permitted the identification of them and the results showed the presence of new substances in addition to those isolated previously. Here we reported the isolation and identification of the new compounds: two new limonoids, 11&#946;,19&#945;-dihydroxi-7- deoxo-7-acetoxy-ichangin e 11&#946;,19&#945;-oxide-7-deacetoxy-7-hidroxy-ichangin, two new prenylated indoles alkaloids, 5-[(3 -dimethylalil-4 -methylidene)-2 -tetrahidrofuran-2 - il]-indol e 5-[(4 -carbomethoxy)-furan-2 -il]-indol and a new bisindol alkaloid, 5 ,6 -[5- methyl-5(7-indol-5 -il-etene-6,7-diil)-3(1-methylprop-2-en-2-il)]-ciclopentane-5 ,6 -diilindol. The following known substances were also obtained: T-cadinol, &#946;-sitosterol, stigmasterol, campesterol, 3-[2 ,6 -dimethoxy-6 ,6 -dimethylpyrano(2 ,3 :3 ,4 ) phenyl]-methylpropionate, 3-oxo-cadinol, lanosta-7,24-dien-21-oic acid-3-oxo, dictamine, &#947;-fagarine, 1-methyl-4-methoxy-2-quinolone, tricoccin S13 acetate, 6- formylindol. Our results showed that the chemical classes isolated from R. praetermissa roots are common to the Rutaceae family, but the prenylated indol alkaloids are not. These compounds are new classes of prenylated indol alkaloids. However, all isolated compounds confirm the assigned it into the tribe Cuspariae. In addition, the compounds were evaluated for: a) in vitro biological activity against trypanosomastigotes forms of Trypanosoma cruzi and amastigotes forms of Leishmania braziliensis; b) enzymatic inhibitory activity on glyceraldehydes- XXXII phospato-dehidrogenase (gGAPDH) of T. cruzi and enzymatic inhibitory activity on adenine-phosphoribosyl-transferase (APRT) of Leishmania tarentolae. None of isolated substances were promising against T. cruzi in vitro test as well as in enzymatic experimental models (gGAPDH e APRT) from which they not showed enzymatic inhibitory activity. Conversely, the T-cadinol was active against L. braziliensis and results in DL50 44 µM. / XXIX Raputia praetermissa (Engler) Emmerich é uma arvoreta encontrada somente na Reserva Florestal Adolpho Ducke, Amazonas, Brasil. O gênero Raputia foi originalmente descrito por Engler, onde várias espécies foram incluídas, mas em 1978, Emmerich propôs dividi-lo em três novos gêneros, Neoraputia, Raputiarana e Sigmathantus com o objetivo de acomodar seis espécies, quatro destas pertencentes a Raputia (incluída na tribo Cuspariae) e duas que ainda não haviam sido descritas. Atualmente este gênero possui 11 espécies. Não há relatos de estudos fitoquímicos em Raputia. Este trabalho descreve o estudo fitoquímico e quimiossistemático e a busca de compostos tripanocida e leishmanicida na raiz de R. praetermissa. O estudo fitoquímico envolveu desde a preparação dos extratos brutos, seguidos pelo fracionamento e isolamento dos compostos através de diferentes métodos cromatográficos. As análises espectroscópicas permitiram a identificação de substâncias conhecidas e inéditas. Neste são descritos o isolamento e identificação de dois limonóides inéditos, 11&#946;,19&#945;-dihidroxi-7-deoxo-7-acetoxi-ichangina e 11&#946;,19&#945;-óxido-7-deacetoxi-7- hidroxi-ichangina, dois alcalóides indólicos prenilados inéditos, 5-[(3 -dimetilalil-4 - metilideno)-2 -tetraidrofurano-2 -il]-indol e 5-[(4 -carbometoxi)-furano-2 -il]-indol, e um alcalóide bisindol também inédito, 5 ,6 -[5-metil-5(7-indol-5 -il-eteno-6,7-diil)-3(1- metilprop-2-en-2-il)]-ciclopentano-5 ,6 -diil-indol, e as substâncias conhecidas, Tcadinol, &#946;-sitosterol, estigmasterol, campesterol, 3-[2 ,6 -dimetoxi-6 ,6 - dimetilpirano(2 ,3 :3 ,4 ) fenil] propianato de metila, 3-oxo-T-cadinol, ácido 3- oxotirucala-7,24-dien-21-óico, dictamina, &#947;-fagarina, 1-metil-4-metoxi-2-quinolona, acetato de tricocina S13, 6-formilindol. Nossos resultados mostram que as classes químicas isoladas são comuns na família Rutaceae, exceto os indólicos prenilados que pertencem a uma nova classe de indólicos. Contudo, todas as substâncias isoladas confirmam o posicionamento de Raputia na tribo Cuspariae. Os compostos isolados foram avaliados quanto: a) Atividade biológica in vitro contra as formas tripomastigotas de Trypanosoma cruzi e amastigotas de Leishmania braziliensis; b) Atividade enzimática inibitória em gGAPDH (Gliceraldeído-3-fosfato-desidrogenase) do T. cruzi e em APRT (adenina-fosforribosil-transferase) de Leishmania tarentolae. Nenhuma das substâncias isoladas foi promissora no teste in vitro contra T. cruzi. No modelo experimental enzimático (gGAPDH e APRT) nenhum composto mostrou atividade inibitória promissora. Por outro lado, o T-cadinol foi ativo contra L. braziliensis resultando em uma DL50 de 44 µM.

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