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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.
1

Studies in the Trichilia-Walsura complex (Meliaceae)

Clark, Terence Paul January 1990 (has links)
Generic delimitation within the Trichilieae (Meliaceae) is considered, with particular reference to the Trichilia P. Browne - Heynea Roxb. ex Sims - Walsura Roxb. complex. Original investigations of leaf-surface micromorphology, palynology and fruit anatomy are made of species of each genus of the tribe and an isoenzyme study is made of species of Trichilia. Heynea and Walsura. The accounts of these studies are extensively illustrated with photographs, scanning-electron-micrographs and annotated drawings. Seed dispersal systems are briefly considered including original field observations of a species of Walsura. In the light of the data revealed by these studies, inter-generic relationships are discussed. The Indo-Malesian genus Walsura is taxonomically revised and the closely related new genus Pseudoclausena is segregated from it and described. Within Walsura. a new section (Ruswala) and three new species (W. dehiscens. W. pachycaulon and W. sarawakensis) are described and one new combination is made (W. trifoliolata ssp. acuminata). The new genus consists of one new species (P. chrysogyne). formerly W. chrysogyne (Miq.) Bakh.f, and W. velutina Ridley is reduced to a new forma of it. Keys are given for the identification of all taxa and the species are illustrated by drawings and (in some cases) by photographs. A cladistic analysis is made of all the species of Walsura. Pseudoclausena and Heynea. taking Trichilia as the outgroup. This, together with the findings of the above studies and published data indicate that Heynea should be considered a distinct genus in the alliance of Walsura. A key for the identification of these four genera is given. The other genera of the tribe are briefly considered and all are maintained as distinct. The great diversity of fruit structures within the tribe provides particularly good characters for the segregation of these genera.
2

Traditional use of Trichilia emetica for treatment of post-inflammatory hyperpigmentation.

Komane, Baatile Mmammoti. January 2010 (has links)
Thesis (MTech. degree in Pharmaceutical Sciences)--Tshwane University of Technology, 2010. / Aims to assess the efficacy and adverse effects of Trichilia emetica in reducing post-inflammatory hyperpigmentation on black skin.
3

Aspects of post-harvest seed physiology and cryopreservation of the germplasm of three medicinal plants indigenous to Kenya and South Africa.

January 2002 (has links)
The current state of global biodiversity is one of sustained and increasing decline especially in developing countries such as South Africa, where, medicinal plants face a particular threat due the herbal medicine trade, and because in situ conservation measures have not stemmed the exploitation of these plants (Chapter 1). Furthermore, seed storage, which offers an efficient ex situ conservation technique, cannot presently be applied to many medicinal plants, either because these species produce short-lived, recalcitrant seeds, or the post-shedding behaviour of the seeds is altogether unknown. This study investigated three medicinal plant species indigenous to Kenya and South Africa: Trichilia dregeana and T. emetica, of which no population inventories exist and no wild populations were encountered locally during the course of this study; and Warburgia salutaris, one of the most highly-utilised medicinal plants in Africa, and which is currently endangered and virtually extinct in the wild in some countries such as South Africa. Aspects of post-shedding seed physiology (Chapter 2) and the responses of the germplasm of the three species to cryopreservation (Chapter 3) were studied using viability and ultrastructural assessment, with the aim of establishing methods for both short-term and the long-term preservation, via appropriate seed storage and cryopreservation, respectively. The effect of cryopreservation on genetic fidelity, a crucial aspect of germplasm conservation, was assessed by polymerase chain reaction (PCR) based random amplified polymorphic DNA (RAPDs), using W. salutaris as a case-study (Chapter 4). The seeds of all three species were found to exhibit non-orthodox behaviour. On relatively slow-drying, seeds of T. dregeana and T. emetica lost viability and ultrastructural integrity at axis water contents of 0.55 g g-l (achieved over 6 d) and 0.42 g g-l (after 3 d) respectively, while flash-drying of embryonic axes facilitated their tolerance of water contents as low as 0.16 g g-l (T. dregeana, flash-dried for 4 h) and 0.26 (T. emetica, flash-dried for 90 min). Seeds of W. salutaris were relatively more tolerant to desiccation, remaining viable at axis water contents below 0.1 g g-l when desiccated for 6 d in activated silica gel. However, excised embryonic axes flash-dried to similar water contents over 90 min lost viability and were ultrastructurally damaged beyond functionality. In terms of storability of the seeds, those of T. dregeana could be stored in the fully hydrated state for at least 5 months, provided that the quality was high and microbial contamination was curtailed at onset of storage, while those T. emetica remained in hydrated storage for about 60 d, before all seeds germinated in storage. Seeds of W salutaris, even though relatively tolerant to desiccation, were not practically storable at reduced water content, losing viability within 49 d when stored at an axis water content of 0.1 g g-l. The seeds of all three species were sensitive to chilling, suffering extensive subcellular derangement, accompanied by loss of viability, when stored at 6 °C. Thus, T. dregeana and T. emetica are typically recalcitrant, while those of W. salutaris are suggested to fit within the intermediate category of seed behaviour. For either recalcitrant or intermediate seeds, the only feasible method of long-term germpalsm preservation may be cryopreservation. Subsequent studies established that whole seeds of W. salutaris could be successfully cryopreserved following dehydration in activated silica gel. However, whole seeds of T. dregeana and T. emetica were unsuitable for cryopreservation, and excised embryonic axes were utilised. For these, in vitro germination methods, as well as cryoprotection, dehydration, freezing and thawing protocols were established. Post-thaw survival of the axes of both species was shown to depend on cryoprotection, rapid dehydration and cooling (freezing) in cryovials. Embryonic axes of T. dregeana regenerated only as callus after cryopreservation, while those of T. emetica generated into apparently normal plantlets. Thawing/rehydration in a 1:1 solution of 1 µM CaC12.2H2O and 1 mM MgC12.6H2O increased the percentage of axes surviving freezing, and that of T. emetica axes developing shoots. The effect of the extent of seed/axis development on onward growth after cryopreservation was apparent for seeds of W. salutaris and excised axes of T. emetica. The seeds of W. salutaris surviving after cryopreservation germinated into seedlings which appeared similar to those from non-cryopreserved seeds, both morphologically and in terms of growth rate. Analysis using PCR-RAPDs revealed that there were no differences in both nucleotide diversity or divergence, among populations of seedlings from seeds which had been sown fresh, or those which had either been dehydrated only, or dehydrated and cryopreserved. Thus, neither dehydration alone, nor dehydration followed by cryopreservation, was associated with any discernible genomic change. The above results are reported and discussed in detail in Chapters 2 to 4, and recommendations and future prospects outlined in Chapter 5. / Thesis (Ph.D.)-University of Natal, Durban, 2002.
4

Busca de substâncias bioativas em plantas amazônicas: Adiscanthus fusciflorus (Rutaceae), Trichilia pallida e T. rubra (Meliaceae) / Search for bioactive substances in the amazon plants: Adiscanthus fusciflorus (RUTACEAE), Trichilia pallida AND T. rubra (MELIACEAE).

Rocha, Waldireny Caldas 12 August 2004 (has links)
Made available in DSpace on 2016-06-02T20:34:44Z (GMT). No. of bitstreams: 1 TeseWCR.pdf: 10434375 bytes, checksum: 36e8a9c56cf09c072ce4bfecfeb78389 (MD5) Previous issue date: 2004-08-12 / Universidade Federal de Sao Carlos / The aim of this work was the search for antiparasitic and insecticide compounds in active extracts from the following amazon plants: A. fusciflorus (Rutaceae), T pallida e T. rubra (Meliaceae). The selected biological models were: 1) antiparasitic activity against the forms tripomastigota of T. cruzi, inhibition of the activity of gGAPDH of T. cruzi, inhibition of the activity of APRT of L. tarentolae and 2) insecticidal activity - against Spodoptera frugiperda and Atta sexdens a leafcutter ant. All the extracts were bioasseyed and liquid-liquid partition was carried out. From this each partition they were obtained five fractions that were obtained from each extract and these were assayed as well. The fractions were selected by two criteria: the) evaluation of the biological activity of the fractions in relation to your respective extracts and chemical profile of each fraction. Through successive fractioning it was possible to isolate and identify series of different compounds such as: dihydrocinnamic acid derivatives, coumarins, alkaloids, triterpenoids and steroids (some of them are described for the first time), limonoids and flavonoids. The identification of the compounds was carried out through different kind of NMR technique and comparison with data from the literature. The search for compounds with inhibitory activity on the enzyme APRT led to the furanoquinoline alkaloids. The results obtained for inhibitory effect of the enzyme gGAPDH of T. cruzi are promising compounds. Some of the isolated compounds showed interesting activity against trypomastigote forms of T. cruzi. The results obtained for inhibitory effect of the enzyme gGAPDH of T. cruzi are promising compounds. Some of the isolated compounds showed interesting activity against trypomastigote forms of T. cruzi. In the search for insecticidal compounds against S. frugiperda it was evaluated the activity of limonoids, cicloartane triterpenes, steroids, flavonoids, cumarins and alkaloids. Special attention was driven to the incorporation of skiamminine and the estimate DL50. In the bioassay carried out to A. sexdens it was observed the toxicity of some extracts, mainly the methanol extract of leaves from A. fusciflorus. It was also observed that some compounds exhibited antimicrobial activity on symbiotic fungi of A. sexdens and for some pathogenic bacteria. In conclusion, in this work it was possible to isolate and identify active compounds in all proposed biological models. / Este trabalho teve como principal objetivo buscar metabólitos secundários com atividade antiparasitária e ou inseticida em A. fusciflorus (Rutaceae), T. pallida e T. rubra (Meliaceae). Os modelos biológicos selecionados foram: 1) Atividade antiparasitária - à forma tripomastigota de T. cruzi, inibição da atividade de gGAPDH de T. cruzi, inibição da atividade de APRT de L. tarentolae e 2) Atividade inseticida - ensaio frente a Spodoptera frugiperda e Atta sexdens uma formiga cortadeira de folhas. Todos os extratos foram bioensaiados e fracionados através de partição líquido-líquido. De cada partição foram obtidas cinco frações que também foram submetidas aos ensaios biológicos. As frações foram selecionadas por dois critérios: a) avaliação dos efeitos biológicos das frações em relação aos seus respectivos extratos e b) perfil químico da fração. Através de fracionamentos sucessivos foi possível isolar e ou identificar várias substâncias de diferentes classes químicas: derivados do ácido diidrocinâmico, cumarinas, alcalóides, triterpenos, esteróides (alguns com estruturas inéditas), limonóides e flavonóides. A identificação estrutural das substâncias se deu através de diferentes técnicas de RMN e comparação com os dados publicados na literatura. Assim, na busca por substância com atividade inibitória da atividade da enzima APRT foi apresentava o efeito de alcalóides; a inibição da atividade da enzima gGAPDH de T. cruzi principalmente causada pelos flavonóides e furanocumarinas e a atividade de algumas substâncias frente as formas tripomastigotas de T. cruzi. Na busca por substâncias inseticidas para S. frugiperda pode-se destacar a atividade de limonóides, triterpenos cicloartanos, esteróides colestanos, flavonóides, cumarinas e alcalóides quando incorporados a dieta artificial dando enfoque à atividade inseticida de esquimianina e à estimativa da sua DL50. Nos ensaios realizados por ingestão com operárias de A. sexdens foi observado a toxicidade de alguns extratos, principalmente o extrato em metanol das folhas de A. fusciflorus e de um triterpenos cicloartano isolado deste extrato que também teve sua atividade avaliada. Foi observado ainda, que algumas substâncias isoladas causaram efeito deletério sobre o fungo simbionte da formiga cortadeira e para algumas bactérias. Assim, ao fim deste trabalho, foram obtidas substâncias ativas frente a todos os modelos biológicos inicialmente propostos.
5

The effect of provenance on the response of the recalcitrant seeds of Trichilia dregeana to drying and chilling.

Oyerinde, Rebecca Opeyemi. January 2011 (has links)
One of the factors that affect the post-harvest behavior of seeds is provenance. Different geographical locations are characterised by different environmental conditions, hence, plant materials harvested from different locations may respond differently to laboratoryinduced stresses. The aim of the present study was to assess the role that provenance plays on the degree of recalcitrance of a single species – a factor that needs to be taken into consideration when choices are to be made for plant germplasm conservation. In this study, seeds of Trichilia dregeana, which have been shown to display recalcitrant post-harvest behavior, were harvested from four locations that were slightly different in climatic conditions: Mtunzini (MTZN), Durban (DBN), Pietermaritzburg (PMB) and Port Edward (P.ED), all within the KwaZulu-Natal province of South Africa. Clean seeds, whose aril and seed coat have been removed, were subjected to different drying and chilling stresses and their responses to the stresses are examined. Excised embryonic axes of the seeds were also subjected to flash (very rapid) drying and their responses to the stress are shown. Although the vegetation of these locations can be categorized as being sub-tropical, the present study suggests that there may be ‘degrees’ in the sub-tropical nature based on the rainfall and maximum temperature data. The ‘degree of sub-tropicality’ is suggested to be in the order MTZN > DBN > P.ED > PMB. Mean seed size assessed as seed length, width and fresh mass varied significantly across the four regions, with seeds from MTZN being the smallest and those from P.ED being the largest. The shedding water content of the embryonic axes of the seeds for 150 min. However, shoot production, root and shoot length and dry mass accumulation showed that axes of seeds from MTZN were the most adversely affected by rapid drying while those from PMB were the least sensitive. When clean whole seeds were dried slowly by burying in silica gel for 36 h, all seeds of the four provenances still retained more than 50% of their shedding water. MTZN seeds lost viability completely from the 24 h of slow drying while seeds from the other three locations retained some viability after 36 h. The order of survival of slow drying was MTZN < DBN < P.ED = PMB. Storage of cleaned whole seeds at chilling temperatures (3oC, 6oC and 16oC) caused increase in the water content of the embryonic axes of the seeds across the four locations. All seeds of the four provenances had lost more than 50% survival after they had been stored at 3oC for 10 weeks. Survival was completely lost from the 12th week for MTZN seeds, from the 14th week for DBN and P.ED seeds and from the 16th week for PMB seeds. There was no survival recorded for seeds across the four regions at the 18th week. The seeds were able to tolerate storage at 6oC for a little longer than those stored at 3oC. Only MTZN seeds completely lost viability at the 18th week; seeds from the other three locations retained some viability throughout the 18 weeks of storage. Storage at 16oC was the most tolerable, as all seeds from the four provenances maintained some viability until the 18th week in storage, with MTZN having the least survival and those from P.ED having the highest survival. Phylogenetic analysis of the internal transcribed spacer (ITS) region of the DBN and PMB samples showed intraspecific levels of genetic variation, and were separated by a genetic distance of 0.9%, an indicator that differences in storage behavior, chilling and desiccation sensitivity between seeds obtained from different collection localities may be genetically based. This study showed that MTZN seeds were the most sensitive, while seeds from PMB and P.ED were the most tolerant, to drying and chilling treatments, respectively. The prevailing climatic conditions may have a bearing on the responses observed in this study. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2011.
6

Aspectos da historia de vida de quatro especies de Trichilia (Meliaceae) na reserva de Santa Genebra, Campinas (SP) / Life history aspects of four Trichilia (Meliaceae) specis in the reserva de Santa Genebra, Campinas (SP)

Rosseto, Vanessa 08 January 2007 (has links)
Orientador: Flavio Antonio Maes dos Santos / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-08T20:06:21Z (GMT). No. of bitstreams: 1 Rosseto_Vanessa_M.pdf: 1782142 bytes, checksum: 9d91cab6c070b924e2ff3078c70d69f9 (MD5) Previous issue date: 2007 / Resumo: A coexistência de espécies arbóreas em florestas tropicais pode estar associada com a partição dos recursos, através da utilização diferencial dos recursos ambientais ao longo do tempo e espaço. O objetivo do trabalho foi avaliar quais os possíveis mecanismos relacionados com a coexistência de espécies arbóreas simpátricas, Trichilia sp. (Meliaceae), em três fisionomias florestais em um fragmento urbano de Campinas, SP. Para tanto, foram feitos três questionamentos centrais: (1) Qual a heterogeneidade ambiental de três fisionomias florestais (Floresta Estacional Semidecídua, Floresta Paludosa e Floresta de Maria-Preta)? (2) As espécies de Trichilia apresentam características estruturais divergentes ao longo da ontogenia, que possibilitem a coexistência das espécies? (3) O padrão espacial das espécies de Trichilia varia nas diferentes fisionomias e possíveis diferenças estão associadas com fatores ambientais específicos? Para o estudo foram utilizadas três escalas espaciais: escala fisionômica (comparação dos descritores ambientais entre as fisionomias), escala local (comparação entre áreas dentro de uma mesma fisionomia) e escala microlocal (comparação entre parcelas de uma mesma área). A umidade do solo foi o único fator ambiental divergente entre a Floresta de Maria-Preta (MP) e a Floresta Estacional Semidecídua (FES), enquanto que a Floresta Paludosa (FP) não diferiu. MP foi considerada uma floresta monodominante, porque a espécie arbórea maria-preta, Diatenopteryx sorbifolia (Sapindaceae), representou mais de 50% do número de indivíduos e área basal na comunidade arbórea. Supõe-se que a monodominância esteja associada com características do solo. Na escala local e microlocal observou-se grande heterogeneidade ambiental e, em muitos casos, áreas de diferentes fisionomias foram mais semelhantes entre si, do que áreas em uma mesma fisionomia. Ao longo da ontogenia as espécies divergiram entre si na morfologia (presença de caule descamado em T. claussenii e crescimento clonal em T. elegans) e no tamanho. O padrão espacial das espécies de Trichilia não variou nas diferentes fisionomias, exceto em uma área com maior valor de umidade do solo na FP, com a ocorrência apenas de T. pallida. O padrão espacial de Trichilia não foi associado com a heterogeneidade ambiental, com exceção do alagamento, que aparentemente é um fator restritivo para a maioria das espécies arbóreas. Com isso, sugere-se que a coexistência das espécies de Trichilia analisadas esteja mais relacionada com diferenças na ocupação do estrato vertical que cada espécie ocupa do que com diferenças nas preferências ambientais. Além disso, supõe-se que a elevada heterogeneidade ambiental encontrada em todas as fisionomias, possibilite às espécies explorar uma ampla gama de condições ambientais, que podem estar relacionadas com a não preferência de algumas espécies por um habitat específico / Abstract: Tree species coexistence in tropical forests can be associated with resource partitioning through differential utilization of environmental resources along the time and space. The study evaluated coexistence mechanisms associated with sympatric tree species of Trichilia sp. (Meliaceae), in three physiognomies in an urban fragment in Campinas, SP. We approach three questions: (1) Which is the existing environmental heterogeneity in three different physiognomies of the forest fragment (Semideciduous Forest, Swamp Forest and Maria-Preta Forest)? (2) Have Trichilia species structural characteristics divergent along of the ontogeny that makes possible the species coexistence? (3) Are the spatial patterns of Trichilia species variable in the physiognomies analyzed and are possible differences related to specific environmental factors? We evaluated these questions in three spatial scales: a physiognomy scale (variations of environmental factors among physiognomies), a local scale (variations among places in the same physiognomy) and microlocal scale (variations among plots in the same place). The soil moisture was the only one environmental variable that differed between Maria-Preta Forest (MP) and Semideciduous Forest (FES), while Swamp Forest (FP) not differed. MP was considered a monodominant forest, because a tree species ¿maria-preta¿, Diatenopteryx sorbifolia (Sapindaceae), presenting more than 50% of individual numbers and basal area in the tree community. We presumed that monodominance is associated with soil characteristics. High environmental heterogeneity was observed in local and microlocal scale. In many cases, places of different physiognomies were more similar than places in a same physiognomy. Trichilia species diverged through ontogeny in morphology (presence of scaled off stem in T. claussenii and clonal growth in T. elegans) and in size. Spatial pattern of Trichilia species not varied in the different physiognomies, except for one sample with greater soil moisture in the FP, where only T. pallida occurred. Spatial pattern of Trichilia was not associated with environmental heterogeneity, except for the flooding, that seeming was restrictive to the establishment of the majority of the species. Then we supposed that Trichilia species coexistence is more associated with differences in the vertical strata that each species occupies than with differences in environmental preferences. Furthermore, we suggests that the high environmental heterogeneity encountered found in all physiognomies, makes possible to the species explore an ample gamma of ambient, that can be related with no preference of species for specific habitats / Mestrado / Mestre em Ecologia
7

Limonóides e protolimonóides de Trichilia elegans ssp. Elegans A. Juss. (Meliaceae) / Limonoids and protolimonoids of Trichilia elegans ssp. Elegans A. Juss. (Meliaceae)

Garcez, Fernanda Rodrigues 11 June 1997 (has links)
o presente trabalho teve como objetivo realizar o estudo químico das sementes de Trichilia elegans ssp. Elegans A. Juss. (coletadas no município de Corumbá, MS), visando o isolamento e identificação ou elucidação estrutural dos seus metabólitos secundários, particularmente limonóides. Da fase diclorometânica, obtida de uma partição efetuada com o extrato etanólico das sementes, foram isoladas, através de técnicas cromatográficas de separação (cromatografia em colunas de sílica gel, de Sephadex LH 20 e CLAE em fase reversa), dezoito substâncias, compreendendo: dois protolimonóides, onze limonóides com esqueleto do tipo obacunol (abertura dos anéis A e D), quatro com esqueleto do tipo ivorensato de metila (abertura dos anéis A, B e D) e 3&#946;-O-&#946;-D-glicopiranosilsitosterol. Todas as substâncias são inéditas, com exceção do esteróide glicosilado e de dois limonóides com esqueleto do tipo obacunol (kihadaninas A e B). As determinações estruturais foram efetuadas com base em dados espectroscópicos de RMN 1H e 13C, incluindo experimentos bidimensionais (COSY 1H-1H, COSY 1H-13C, HMQC, NOESY e HMBC); a partir de informações obtidas dos espectros de massas e na região do IV e através de dados de difração de raios-X. Quatro dos limonóides obtidos foram submetidos a um ensaio biológico de atividade antitumoral, utilizando-se linhagens mutantes de Saccharomyces cerevisiae, porém, mostraram-se inativos. / The present work describes the isolation and identification or structural elucidation of the chemical constituents of the seeds of Trichilia elegans ssp. Elegans A. Juss., collected in Corumbá, MS. From the dichloromethane solubles, obtained from partition of the ethanolic extract from the seeds, eighteen substances have been isolated, after a combination of column and flash chromatography on silica gel, gel filtration and reversed phase HPLC separations. The isolated substances have been characterized as two new protolimonoids, nine new obacunol- and four new methyl ivorensate-type limonoids, in addition to two known limonoids belonging to the obacunol group (kihadanins A and B) and 3-O-&#946-D-glucopyranosyl-sitosterol. The structures of these compounds have been established on the basis of 1D (1H, 13C) and 2D (1H-1H and 1H-13C COSY, HMQC, HMBC and NOESY) NMR spectroscopic techniques, IR and mass spectral data and X-ray crystallographic analyses. Four of the isolated limonoids have been tested against DNA reparr deficient mutants of Saccharomyces cerevisiae but, nevertheless, shown to be inactive.
8

Limonóides e protolimonóides de Trichilia elegans ssp. Elegans A. Juss. (Meliaceae) / Limonoids and protolimonoids of Trichilia elegans ssp. Elegans A. Juss. (Meliaceae)

Fernanda Rodrigues Garcez 11 June 1997 (has links)
o presente trabalho teve como objetivo realizar o estudo químico das sementes de Trichilia elegans ssp. Elegans A. Juss. (coletadas no município de Corumbá, MS), visando o isolamento e identificação ou elucidação estrutural dos seus metabólitos secundários, particularmente limonóides. Da fase diclorometânica, obtida de uma partição efetuada com o extrato etanólico das sementes, foram isoladas, através de técnicas cromatográficas de separação (cromatografia em colunas de sílica gel, de Sephadex LH 20 e CLAE em fase reversa), dezoito substâncias, compreendendo: dois protolimonóides, onze limonóides com esqueleto do tipo obacunol (abertura dos anéis A e D), quatro com esqueleto do tipo ivorensato de metila (abertura dos anéis A, B e D) e 3&#946;-O-&#946;-D-glicopiranosilsitosterol. Todas as substâncias são inéditas, com exceção do esteróide glicosilado e de dois limonóides com esqueleto do tipo obacunol (kihadaninas A e B). As determinações estruturais foram efetuadas com base em dados espectroscópicos de RMN 1H e 13C, incluindo experimentos bidimensionais (COSY 1H-1H, COSY 1H-13C, HMQC, NOESY e HMBC); a partir de informações obtidas dos espectros de massas e na região do IV e através de dados de difração de raios-X. Quatro dos limonóides obtidos foram submetidos a um ensaio biológico de atividade antitumoral, utilizando-se linhagens mutantes de Saccharomyces cerevisiae, porém, mostraram-se inativos. / The present work describes the isolation and identification or structural elucidation of the chemical constituents of the seeds of Trichilia elegans ssp. Elegans A. Juss., collected in Corumbá, MS. From the dichloromethane solubles, obtained from partition of the ethanolic extract from the seeds, eighteen substances have been isolated, after a combination of column and flash chromatography on silica gel, gel filtration and reversed phase HPLC separations. The isolated substances have been characterized as two new protolimonoids, nine new obacunol- and four new methyl ivorensate-type limonoids, in addition to two known limonoids belonging to the obacunol group (kihadanins A and B) and 3-O-&#946-D-glucopyranosyl-sitosterol. The structures of these compounds have been established on the basis of 1D (1H, 13C) and 2D (1H-1H and 1H-13C COSY, HMQC, HMBC and NOESY) NMR spectroscopic techniques, IR and mass spectral data and X-ray crystallographic analyses. Four of the isolated limonoids have been tested against DNA reparr deficient mutants of Saccharomyces cerevisiae but, nevertheless, shown to be inactive.
9

Busca de compostos inseticidas : estudo de espécies do gênero Trichilia (Meliaceae). / Search of insecticidal compounds - study of species from the genus Trichilia (Meliaceae)

Matos, Andréia Pereira 15 May 2006 (has links)
Made available in DSpace on 2016-06-02T20:34:05Z (GMT). No. of bitstreams: 1 TeseAPM.pdf: 3545061 bytes, checksum: 5ef30df4bdf3fc845cd85984795b7e0c (MD5) Previous issue date: 2006-05-15 / This work describes the results of the search for insecticidal compounds from the Meliaceae family. The samples assayed against fall armyworm Spodoptera frugiperda were the hexane, methanol and hydromethanol extracts of twigs, leaves, seeds, aril and exocarp of T. catigua; twigs, leaves, fruits, seeds, aril and exocarp of T. claussenii and twigs, leaves and fruits of T. elegans. The hexane and methanol extracts of leaves, hexane of twigs and methanol of fruits from T. claussenii showed to possess the higher insecticidal activity against S. frugiperda. Nevertheless, the hexane and methanol extracts of fruits from T. elegans showed the highest rate of larval mortality (100 %). The hydromethanol extract of T. elegans showed moderate insecticidal activity and also showed growth inhibition and antifeedant activities. The active extracts were fractionated and the chemical study led to isolation of 20 compounds, including limonoids, triterpenes, coumarins, steroids and one sesquiterpene. From the hexane extract of leaves from T. claussenii were isolated the steroids &#946;-sitosterol, stigmasterol, campesterol and sitostenone; the triterpenoids &#945;-amyrin, &#946;-amyrin, lupeol, lupenone, in addition to the cycloartane triterpene 24-methylen-26- hydroxycicloartan-3-on and sesquiterpene criptomeridiol. From the methanol extract of leaves of T. claussenii were isolated the steroids 24-methylen-3 &#946;,4 &#946;,22 &#945;- trihydroxy-colesterol and 3- &#946;-O- &#946;-D-glucopyranosilsitosterol. From the methanol extract of fruits from T. elegans were isolated the coumarins 6,7- dimethoxycoumarin, 6-methoxy-7-hydroxycoumarin e 7-hydroxycoumarin. The same coumarins and the steroids were also isolated from the hexane extract of fruits from T. elegans. The limonoids cedrelone and 11 &#946;-methoxycedrelone were isolated from the hexane extract of aril from T. catigua. Limonoids methylangolensate together with the photogedunin epimeric mixture were isolated from the methanol extract of aril from T. catigua. This is first report of the isolation of limonoids from T. catigua. Triterpens isolated from Cedrela fissilis and limonoids isolated from Cipadessa fruticosa (Meliaceae) were tested against S. frugiperda. Among them odoratol showed the best results (insecticidal activity, growth inhibition and antifeedant). Febrifugin A showed the highest rate of mortality of total cycle (at 50 mg kg-1) of 73.3%. / Este trabalho apresenta os resultados obtidos dos ensaios biológicos dos extratos hexânico, metanólico e hidrometanólico de ramos, folhas, sementes, arilo e exocarpo de T. catigua; ramos, folhas, frutos, sementes, arilo e exocarpo de T. claussenii e ramos, folhas e sementes de T. elegans sobre à lagarta-do-cartucho do milho Spodoptera frugiperda. Os extratos hexânico e metanólico de folhas, hexânico de ramos e metanólico de frutos de T. claussenii apresentaram alta atividade inseticida frente a S. frugiperda. No entanto, os extratos hexânico e metanólico de frutos de T. elegans causaram a mais alta taxa de mortalidade larval (100 %), já o extrato hidrometanólico apresentou atividade inseticida moderada e mostrou-se inibidor de crescimento e da alimentação. Os extratos ativos foram fracionados e o estudo químico levou ao isolamento de 20 metabólitos, incluindo limonóides, triterpenos, cumarinas, esteróides e um sesquiterpeno. Do extrato hexânico de folhas de T. claussenii foram isolados os esteróides &#946;-sitosterol, estigmasterol, campesterol, sitostenona e os triterpenóides &#945;-amirina, &#946;-amirina, lupeol, lupenona, além do triterpeno do tipo cicloartano 24-metileno-26-hidroxicicloartan-3-ona e do sesquiterpeno criptomeridiol. Do extrato metanólico de folhas de T. claussenii foram isolados somente os esteróides 24-metileno-3 &#946;,4 &#946;,22 &#945;-triidroxi-colesterol e - &#946;-O- &#946;-Dglucopiranosil sitosterol. Ao se fracionar o extrato metanólico de frutos de T. elegans foram isoladas as cumarinas 6,7-dimetoxicumarina, 6-metoxi-7- hidroxicumarina e 7-hidroxicumarina. As mesmas cumarinas e os esteróides foram novamente isolados do extrato hexânico de frutos de T. elegans. Os limonóides cedrelona e 11&#946;-metoxicedrelona foram isolados do extrato hexânico do arilo de T. catigua. Além destes limonóides, o angolensato de metila e a mistura epimérica de fotogedunina foram isolados do extrato metanólico do arilo de T. catigua. Este é o primeiro relato do isolamento de limonóides de T. catigua. Triterpenóides isolados de Cedrela fissilis e limonóides isolados de Cipadessa fruticosa (Meliaceae) foram ensaiados frente a S. frugiperda. Dentre os triterpenóides testados, o odoratol apresentou os melhores resultados (atividade inseticida, inibidor de crescimento e inibidor de alimentação). A febrifugina A causou a mais alta taxa de mortalidade do ciclo total (a 50 mg kg-1) de 73,3%.
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Atividade inseticida de espécies de trichilia frente à lagarta-do-cartucho do milho spodoptera frugiperda / INSECTICIDAL ACTIVITY OF Trichilia SPECIES AGAINST ON FALL ARMYWORM Spodoptera frugiperda.

Nebo, Liliane 18 July 2008 (has links)
Made available in DSpace on 2016-06-02T20:36:19Z (GMT). No. of bitstreams: 1 2066.pdf: 3869548 bytes, checksum: 919d361643b7d2da104c8bf183496f29 (MD5) Previous issue date: 2008-07-18 / Financiadora de Estudos e Projetos / This work presents the phytochemical study and biological assays carried out with organic extracts of fruits and seeds from Trichilia claussenii, T. elegans and inflorescence from T. catigua against S. frugiperda. Among the extracts assayed, the methanol extracts of seeds from T. claussenii and inflorescence from T. catigua presented the highest insecticidal activity, with 64,0 and 64,4 % of mortality, respectively. The bioassay-guided study of the methanol extract of seeds from T. claussenii led to identification of &#56256;&#56870;-phenylalkyl and alkenyl fatty acids, active substances in this extract. The flavonoid ent-catequin was isolated from the methanol extract of inflorescence from T. catigua and it was associated with the insecticidal activity found in this extract. Fatty acids with the methylene chains ranging from C-5 to C-16 were assayed against S. frugiperda. Tests showed that the hexanoic, nonanoic and decanoic acids, displayed the highest rate of mortality at concentration of 10,0 mg/mL. The study of the three species allowed isolating and identifying the following compounds: a mixture of &#56256;&#56870;-phenylalkyl and alkenyl fatty acids, &#56256;&#56854;-lactonas, 4-hydroxy-N-methylproline, N-methylproline, uridine, uracile, entcatequin, 5-O-cafeoylquinic acid and the steroids 3-&#56256;&#56853;-O-&#56256;&#56853;-Dglucopyranosilsitosterol, &#56256;&#56853;-sitosterol, campesterol, estigmasterol e sitostenone. The limonoids 11&#56256;&#56853;-acetoxyobacunone and 1,2-dihiyro-1&#56256;&#56622;-acetoxy-11&#56256;&#56853;-acetoxy-14,15-epoxycneorin R were isolated for the first time from a Trichilia species. / Este trabalho apresenta o estudo fitoquímico e os ensaios biológicos realizados com os extratos orgânicos dos frutos e sementes das espécies Trichilia claussenii, T. elegans e inflorescências T. catigua sobre Spodoptera frugiperda. Dentre os extratos ensaiados, os extratos metanólicos das sementes de T. claussenii e inflorescências de T. catigua foram os que apresentaram a mais alta atividade inseticida, com 64,0 e 64,4 % de mortalidade, respectivamente. O estudo biomonitorado do extrato metanólico das sementes de T. claussenii levou a identificação dos ácidos &#56256;&#56870;-fenil alcanóicos e alquenóicos, substâncias ativas neste extrato. Do extrato metanólico das inflorescências de T. catigua foi isolado o flavonóide ent-catequina, associado à atividade inseticida encontrada neste extrato. Ácidos graxos com cadeias metilênicas variando entre C-5 a C-16 foram testados sobre S. frugiperda. Ensaios mostraram que os ácidos hexanóico, nonanóico e decanóico apresentaram altas taxas de mortalidade na concentração de 10,0 mg/mL. Através do estudo dessas três espécies foi possível isolar e ou identificar as substâncias: ácidos &#56256;&#56870;-fenil alcanóicos e alquenóicos, &#56256;&#56854;-lactonas, 4-hidróxi-N-metilprolina, N-metilprolina, uridina, uracila, ent-catequina, ácido 5-O-cafeoilquínico, os esteróides 3-&#56256;&#56853;-O-&#56256;&#56853;-D-glucopiranosil sitosterol, &#56256;&#56853;-sitosterol, campesterol, estigmasterol e sitostenona. Sendo os limonóides 11&#56256;&#56853;-acetoxiobacunona e 1,2 diidro-1&#56256;&#56622;-acetoxi-11&#56256;&#56853;-acetoxi-14,15-epoxicneorina R isolados pela primeira vez no gênero Trichilia.

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