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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.
191

Insect growth inhibitors from asteraceous plant extracts

Salloum, Gregory Stewart January 1987 (has links)
Petrol and ethanolic extracts of six asteraceous weeds were added to artificial diet and screened for inhibition of larval growth on variegated cutworm, Peridroma saucia (Hbn.). Petrol and ethanolic extracts of Artemisia tridentata and Chamomilla suaveolens and ethanolic extracts of Chrysothamnus nauseosus and Centaurea diffusa were highly inhibitory at five times the naturally occurring concentrations. The two C. suaveolens extracts and the ethanol extract of A. tridentata were active at the natural concentration (100%) and were further examined at 20, 40, 60, and 80% of this level. Inhibition of larval growth was directly related to concentration for each of the three extracts tested. EC₅₀'S (effective concentration to inhibit growth by 50% relative to controls) for the three extracts were 36-42% of the naturally occurring level in the plants. Nutritional indices were calculated for second instar P. saucia feeding on the active ethanolic A. tridentata extract and the petrol extract from C. suaveolens. The relative growth rate (RGR) of P. saucia larvae fed the ethanolic extract of A. tridentata in artificial diet was significantly lower than that in larvae fed diet with the petrol extract of C. suaveolens and larvae on control diet. Dietary utilization was significantly lower for larvae fed the A. tridentata extract. Results of a field trial indicated that a single treatment of A. tridentata extract at the equivalent of 0.2 g/ml could protect cabbage significantly better than the carrier solvent (30% aq ethanol) or distilled water as measured by a visual damage estimate. An insecticide standard, deltamethrin (17.9 µg/1 with 0.4% Superspred TM ), suppressed pest damage significantly better than the A. tridentata-extract treatment. A residual oviposition deterrency to Pieris rapae was found in the field results. Caged experiments in the laboratory confirmed the contact oviposition deterrency of the A. tridentata extract at 0.2 g/ml. Offspring of field-collected P. saucia larvae grew 2.5-fold heavier than larvae from the laboratory colony. However, diet with the A. tridentata extract inhibited both field-collected and laboratory reared saucia larvae equally when compared to their respective controls fed untreated diet. In summary, these results indicate the potential benefit of using specific unrefined plant extracts for growth inhibitors and oviposition deterrents against insect pests. The contribution of individual phytochemicals in the A. tridentata ethanolic extract to growth inhibition or oviposition deterrency is currently speculative. / Land and Food Systems, Faculty of / Graduate
192

Phytochemical and biological studies of Helichrysum cymosum

Jadalla, Baraa Mohamed Ibrahim Soliman January 2020 (has links)
Masters of Science / Diabetes mellitus (DM) is well known as a group of systemic metabolic disorders with a considerable mortality rate around the world. Hyperglycemia is the main consequence of DM, which results from the shortage in insulin production or degradation of produced insulin. Other internal and external factors including obesity, oxidative stress, and sedentary lifestyle have been also suggested as the causes of DM. Among the well-known existing types of DM, type 1 and 2 are the most common. Treatment of type 1 necessitates insulin injection, while type II can be controlled by physical exercises, diet control in addition to different synthetic antidiabetic drugs. However, their effectiveness is restricted because of the high cost and unfriendly side effects. There is a significant need for producing alternative and more bioactive antidiabetic drugs from natural sources. Natural products are a well-known source for the discovery of new scaffold for drugs discovery, and South Africa is one of the most important megaflora with a high percentage of endemism. South Africa is home to about 245 species of Helichrysum species, which are generally rich sources of secondary metabolites, especially flavonoids, which give them a great value for global acceptability and wide application in the pharmaceutical fields as antibacterial, anti-inflammatory, antioxidant, and antidiabetic agents. The phytochemical investigation of the methanolic extract of H. cymosum resulted in the isolation and identification of seven pure compounds (1-7). Structural characterization of these isolated compounds was conducted using 1D NMR, in comparison with reported spectroscopic data. The in vitro bio-evaluation of H. cymosum against alpha-glucosidase shown that 5 exhibited the highest alpha-glucosidase inhibitory activity with IC50 value of 13 μM, followed by 7 and 3 with IC50 values of 18.16 μM and 44.4 μM respectively. Additionally, strong total antioxidant capacities were displayed by 6 and 2 as ORAC (122.86 ± 0.7 and 91.70 ± 0.4 μM TE/mL) respectively as well as 5 and 7 as FRAP (1006.34 ± 1.7; 977.79 ± 0.8) μM AAE/g. This is the first scientific report to be carried out on alpha-glucosidase inhibitory activities and antioxidant capacities of H. cymosum constituents. The findings suggest that these compounds might become prominent natural candidates to inhibit alpha-glucosidase as well as oxidative stress related to diabetes with the prospect to be employed in the formulation of diabetes drugs upon further biological studies.
193

Metabolomic analysis on anti-HIV activity of selected Helichrysum species

Emamzadeh Yazdi, Simin January 2019 (has links)
Since the beginning of human civilization, medicinal plants have been used to treat a variety of infectious and non-infectious diseases. The therapeutic properties of phytochemicals have been recognized since ancient human history. The genus Helichrysum Mill. with its attractive flowers consist of an estimated 500‒600 species in the Asteraceae family. In South Africa and Namibia there are about 244‒250 species with tremendous morphological diversity. Several Helichrysum species are widely used by the indigenous population to treat various disorders such as wounds, infections, respiratory conditions, headaches, coughs, colds and fevers. Several of the Helichrysum species exhibit antiviral activity with the most relevant to this study being the discovery of anti-human immunodeficiency virus (anti-HIV) and anti-reverse transcriptase (anti-RT) activity of some species. Drug discovery and development, from the early stages of a promising compound to the final medication, is an intensive, expensive and incremental process. The ultimate goal is to identify a molecule with the desired effect in the human body and to establish its quality, safety and efficacy for treating patients. The ability to combine high-throughput analytical techniques like metabolomic and other experimental approaches with drug discovery will speed up the development of safer, more effective and better-targeted therapeutic agents. The rapidly emerging field of metabolomics and molecular docking analysis provides valuable information on drug activity, toxicity, customized drug treatments and can predict therapeutic outcomes. Extraction of the aerial parts of 32 Helichrysum species was done using polar [methanol (MeOH) 50%: distilled water (dH2O) 50%] and non-polar [hexane (Hex), dichloromethane (DCM) and acetone (Ace)] solvent systems. Anti-human immunodeficiency virus bioassays on the live HI virus revealed that polar extracts of H. mimetes and H. chrysargyrum at 2.5 μg/mL and 25 μg/mL, polar and non-polar extracts of H. infuscum at 25 μg/mL and polar and non-polar extracts of H. zeyheri, H. setosum, H. platypterum and H. kraussii at 2.5 and 25 μg/mL, had higher than 90% inhibitory activity. The polar extract of H. mimetes also exhibited reverse transcriptase (RT) inhibition as a possible indication of the mechanism of action. Proton nuclear magnetic resonance (1H NMR) spectra of the polar extracts exhibited the presence of aromatic compounds and carbohydrate moieties. Principal component analysis (PCA) of the polar extracts showed clustering related to the activity of the extracts with good predictability scores (Q2 > 0.5). However, orthogonal projections to latent structures discriminant analysis (OPLS-DA) predictability of the model was low based on the Q2 at approximately 0.25. Quinic acid (QA), isolated from H. mimetes showed promising anti-RT activity [50% inhibition concentration (IC50) = 53.82 μg/mL] which was comparable to the positive drug control, doxorubicin (IC50 = 40.31 μg/mL). The molecular docking study revealed the probable binding site and conformation of QA within cavity 4, with a docking score of -8.03. The docking score of doxorubicin within cavity 4 was -7.87. With this study, it was shown that metabolomic analysis as a tool to predict anti-HIV activity in Helichrysum species can be valuable to shorten the process. Moreover, the study of molecular docking revealed the mechanism action of quinic acid and doxorubicin against RT. / Thesis (PhD)--University of Pretoria, 2019. / Plant Production and Soil Science / PhD / Unrestricted
194

Redes neurais e algoritmos genéticos no estudo quimiossistemático da família Asteraceae / Neural Network and Genetic Algorithms in the Chemosystematic study of Asteraceae Family

Correia, Mauro Vicentini 16 March 2010 (has links)
No presente trabalho duas metodologias da área de inteligência artificial (Redes Neurais e Algoritmos Genéticos) foram utilizadas para realizar um estudo Quimiossistemático da família Asteraceae. A família Asteraceae é uma das maiores famílias entre as Angiospermas, conta com aproximadamente 24.000 espécies. As espécies da família produzem grande diversidade de metabólitos secundários, entre os quais merecem destaque os terpenóides, poliacetilenos, flavonóides e cumarinas. Para um melhor entendimento da diversidade química da família construiu-se um Banco de Dados com as ocorrências de doze classes de metabólitos (monoterpenos, sesquiterpenos, sesquiterpenos lactonizados, diterpenos, triterpenos, cumarinas, flavonóides, poliacetilenos, benzofuranos, benzopiranos, acetofenonas e fenilpropanóides) produzidos pelas espécies da família. A partir desse banco três diferentes estudos foram realizados. No primeiro estudo, utilizando os mapas auto-organizáveis de Kohonen e o banco de dados químico classificado segundo duas das mais recentes filogenias da família foi possível realizar com sucesso separações de tribos e gêneros da família Asteraceae. Também foi possível indicar que a informação química concorda mais com a filogenia de Funk (Funk et al. 2009) do que com a filogenia de Bremer (Bremer 1994, 1996). No estudo seguinte, onde se objetivou a criação de modelos de previsão dos números de ocorrências das doze classes de metabólitos, utilizando o perceptron de múltiplas camadas com algoritmo de retropropagação de erro, o resultado foi insatisfatório. Apesar de em algumas classes de metabólitos a fase de treino da rede apresentar resultados satisfatórios, a fase de teste mostrou que os modelos criados não são capazes de realizar previsão para dados aos quais eles não foram submetidos na fase de treino, e portanto não são modelos adequados para realizar previsões. Finalmente, o terceiro estudo consistiu na criação de modelos de regressão linear utilizando como método de seleção de variáveis os algoritmos genéticos. Nesse estudo foi possível indicar que os monoterpenos e os sesquiterpenos são bastante relacionados biossinteticamente, também foi possível indicar que existem relações biossintéticas entre monoterpenos e diterpenos e entre sesquiterpenos e triterpenos / In this study two methods of artificial intelligence (neural network and genetic algorithms) were used to work out a Chemosystematic study of the Asteraceae family. The family Asteraceae is one of the largest families among the Angiosperms, having about 24,000 species. The species of the family produce a large diversity of secondary metabolites, and some worth mentioning are the terpenoids, polyacetylenes, flavonoids and coumarins. For a better understanding of the chemical diversity of the family a database was built up with the occurrences of twelve classes of metabolites (monoterpenes, sesquiterpenes, lactonizadossesquiterpenes, diterpenes, triterpenes, coumarins, flavonoids, polyacetylenes, Benzofurans, benzopyrans, acetophenones and phenylpropanoids) produced by species of the family. From this database three different studies were conducted. In the first study, using the Kohonen self-organized map and the chemical data classified according to two of the most recent phylogenies of the family, it was possible to successfully separatethe tribes and genera of the Asteraceae family. It was also possible to indicate that the chemical information agrees with the phylogeny of Funk (Funk et al. 2009) than with the phylogeny of Bremer (Bremer 1994, 1996). In the next study, which aims at creating models to predict the number of occurrences of the twelve classes of metabolites using multi-layer perceptron with backpropagation algorithm error, the result was found unsatisfactory. Although in some classes of metabolites the training phase of the network has satisfactory results, the test phase showed that the models created are not able to make prevision for data to which they were submitted in the training phase and thus are not suitable models for predictions. Finally, the third study was the creation of linear regression models using a genetic algorithm method of variable selection. This study could indicate that the monoterpenes and sesquiterpenes are closely related biosynthetically, and was also possible to indicate that there are biosynthetic relations between monoterpenes and diterpenes and between sesquiterpenes and triterpenes
195

A tribo Mutisieae cass. (Asteraceae), sensu Cabrera, no Rio Grande do Sul e suas relações biogeográficas

Mondin, Claudio Augusto January 1996 (has links)
Foram levantadas as espécies da tribo Mutisieae (Asteraceae), sensu CABRERA (1977) ocorrentes no Rio Grande do Sul, Brasil. No total foram encontradas 48 espécies, quatro subespécies e duas variedades distribuídas em doze gêneros e quatro subtribos. São apresentadas descrições da tribo e dos gêneros e chaves das subtribos, gêneros e espécies. É apresentado um índex com a relação organizada alfabeticamente das espécies e sinônimos. São citadas pela primeira vez para o Rio Grande do Sul Pamphalea smithii, Perezia catharinensis e Trixis thyrsoidea, e, para o Brasil, Chaptalia arechavaletae, Pamphalea missionum e Perezia squarrosa ssp. squarrosa. Cita-se uma nova espécie para a ciência, Holocheilus monocephalus. Discute-se as formas de vida, habitat e dispersão das espécies e estabelecem-se padrões de distribuição dos gêneros e espécies. São apresentados mapas de ocorrência das espécies, e faz-se uma análise qualitativa da sua distribuição nas regiões fisiográficas do Rio Grande do Sul, discutindose a diversidade de cada região associada a fatores ambientais e a amplitude de ocorrência dos táxons. Dez regiões fisiográficas do Rio Grande do Sul e quatro estações austro-sul-americanas constituíram quatorze unidades amostrais que foram comparadas entre si quanto à presença ou ausência das espécies da tribo Mutisieae, através da aplicação do índice de Jaccard, utilizando-se métodos de classificação e ordenação. Na análise de agrupamentos utilizou-se o critério "soma dos quadrados", e na ordenação o método utilizado foi o da "análise das coordenadas principais". Obtiveram-se dois grupos principais sensivelmente coincidentes com unidades biogeográficas reconhecidas por CABRERA & WILLINK (1980) e TAKHTAJAN (1986). Ficou evidente, ainda, a existência de um subgrupo de transição, geograficamente intermediário entre os dois grupos principais. São analisadas as afinidades entre as unidades amostrais baseadas em fatores ambientais. Faz-se uma reavaliação da área ancestral da família Asteraceae baseada nos resultados das análises deste estudo em relação àquela apresentada por BREMER (1992). Propõe-se que a área austro-sul-americana extra-andina situada desde a Patagônia até aproximadamente o paralelo de 30°S, no Rio Grande do Sul, passe a ser a região mais provavelmente vinculada à área ancestral da família Asteraceae. / The species of the tribe Mutisieae (Asteraceae) , sensu CABRERA (1977) occurring in Rio Grande do Sul, Brazil, w ere surveyed. Forty-eight species, four subspecies and two varieties were found, belonging to t welve genera and four subtribes. Descriptions of the tribe and genera as well as keys to the subtribes, genera and species are provided. An index with a list of the species and synonyms in alphabetical arder is displayed. Pampha/ea smithii, Perezia catharinensis and Trixis thyrsoidea are new geographical novelties to Rio Grande do Sul, whilst Chaptalia arechavaletae, Pamphalea missionum and Perezia squarrosa ssp. squarrosa are new botanical events to Brazil. A new species, Holocheilus monocephalus, is cited. Life forms, habitat and dispersai of the species are discussed and distributional patterns of the genera and species are established. Distribution maps of the species as well as a qualitative analysis of their distribution in the physiographical regions of Rio Grande do Sul are provided, with discussion of each region related to environmental features and geographical range of the species. Classification and ordenation techniques were used with application of Jaccard's coefficient to compare ten physiographical regions of Rio Grande do Sul and four austrosouth- american stands among themselves. "Sum-of-squares" was used in cluster analysis while "principal coordinates analysis" was applied in ordenation. Two main groups were obtained, strongly concurrent with biogeographical units recognized by CABRERA & WILLINK (1980) and TAKHTAJAN (1986). A transitional subgroup, geographically placed between the two main groups, was pointed out and cleared. Relationships among sampling units based on environmental features are analyzed. A new approach of ancestral area of the family Asteraceae is accomplished regarding BREMER'S (1992) analysis. lt is proposed that the austro-south-american extra-andean area situated since Patagonia to about 30°S in Rio Grande do Sul is the most likely region linked to ancestral area of the Asteraceae.
196

A tribo Mutisieae cass. (Asteraceae), sensu Cabrera, no Rio Grande do Sul e suas relações biogeográficas

Mondin, Claudio Augusto January 1996 (has links)
Foram levantadas as espécies da tribo Mutisieae (Asteraceae), sensu CABRERA (1977) ocorrentes no Rio Grande do Sul, Brasil. No total foram encontradas 48 espécies, quatro subespécies e duas variedades distribuídas em doze gêneros e quatro subtribos. São apresentadas descrições da tribo e dos gêneros e chaves das subtribos, gêneros e espécies. É apresentado um índex com a relação organizada alfabeticamente das espécies e sinônimos. São citadas pela primeira vez para o Rio Grande do Sul Pamphalea smithii, Perezia catharinensis e Trixis thyrsoidea, e, para o Brasil, Chaptalia arechavaletae, Pamphalea missionum e Perezia squarrosa ssp. squarrosa. Cita-se uma nova espécie para a ciência, Holocheilus monocephalus. Discute-se as formas de vida, habitat e dispersão das espécies e estabelecem-se padrões de distribuição dos gêneros e espécies. São apresentados mapas de ocorrência das espécies, e faz-se uma análise qualitativa da sua distribuição nas regiões fisiográficas do Rio Grande do Sul, discutindose a diversidade de cada região associada a fatores ambientais e a amplitude de ocorrência dos táxons. Dez regiões fisiográficas do Rio Grande do Sul e quatro estações austro-sul-americanas constituíram quatorze unidades amostrais que foram comparadas entre si quanto à presença ou ausência das espécies da tribo Mutisieae, através da aplicação do índice de Jaccard, utilizando-se métodos de classificação e ordenação. Na análise de agrupamentos utilizou-se o critério "soma dos quadrados", e na ordenação o método utilizado foi o da "análise das coordenadas principais". Obtiveram-se dois grupos principais sensivelmente coincidentes com unidades biogeográficas reconhecidas por CABRERA & WILLINK (1980) e TAKHTAJAN (1986). Ficou evidente, ainda, a existência de um subgrupo de transição, geograficamente intermediário entre os dois grupos principais. São analisadas as afinidades entre as unidades amostrais baseadas em fatores ambientais. Faz-se uma reavaliação da área ancestral da família Asteraceae baseada nos resultados das análises deste estudo em relação àquela apresentada por BREMER (1992). Propõe-se que a área austro-sul-americana extra-andina situada desde a Patagônia até aproximadamente o paralelo de 30°S, no Rio Grande do Sul, passe a ser a região mais provavelmente vinculada à área ancestral da família Asteraceae. / The species of the tribe Mutisieae (Asteraceae) , sensu CABRERA (1977) occurring in Rio Grande do Sul, Brazil, w ere surveyed. Forty-eight species, four subspecies and two varieties were found, belonging to t welve genera and four subtribes. Descriptions of the tribe and genera as well as keys to the subtribes, genera and species are provided. An index with a list of the species and synonyms in alphabetical arder is displayed. Pampha/ea smithii, Perezia catharinensis and Trixis thyrsoidea are new geographical novelties to Rio Grande do Sul, whilst Chaptalia arechavaletae, Pamphalea missionum and Perezia squarrosa ssp. squarrosa are new botanical events to Brazil. A new species, Holocheilus monocephalus, is cited. Life forms, habitat and dispersai of the species are discussed and distributional patterns of the genera and species are established. Distribution maps of the species as well as a qualitative analysis of their distribution in the physiographical regions of Rio Grande do Sul are provided, with discussion of each region related to environmental features and geographical range of the species. Classification and ordenation techniques were used with application of Jaccard's coefficient to compare ten physiographical regions of Rio Grande do Sul and four austrosouth- american stands among themselves. "Sum-of-squares" was used in cluster analysis while "principal coordinates analysis" was applied in ordenation. Two main groups were obtained, strongly concurrent with biogeographical units recognized by CABRERA & WILLINK (1980) and TAKHTAJAN (1986). A transitional subgroup, geographically placed between the two main groups, was pointed out and cleared. Relationships among sampling units based on environmental features are analyzed. A new approach of ancestral area of the family Asteraceae is accomplished regarding BREMER'S (1992) analysis. lt is proposed that the austro-south-american extra-andean area situated since Patagonia to about 30°S in Rio Grande do Sul is the most likely region linked to ancestral area of the Asteraceae.
197

A tribo Mutisieae cass. (Asteraceae), sensu Cabrera, no Rio Grande do Sul e suas relações biogeográficas

Mondin, Claudio Augusto January 1996 (has links)
Foram levantadas as espécies da tribo Mutisieae (Asteraceae), sensu CABRERA (1977) ocorrentes no Rio Grande do Sul, Brasil. No total foram encontradas 48 espécies, quatro subespécies e duas variedades distribuídas em doze gêneros e quatro subtribos. São apresentadas descrições da tribo e dos gêneros e chaves das subtribos, gêneros e espécies. É apresentado um índex com a relação organizada alfabeticamente das espécies e sinônimos. São citadas pela primeira vez para o Rio Grande do Sul Pamphalea smithii, Perezia catharinensis e Trixis thyrsoidea, e, para o Brasil, Chaptalia arechavaletae, Pamphalea missionum e Perezia squarrosa ssp. squarrosa. Cita-se uma nova espécie para a ciência, Holocheilus monocephalus. Discute-se as formas de vida, habitat e dispersão das espécies e estabelecem-se padrões de distribuição dos gêneros e espécies. São apresentados mapas de ocorrência das espécies, e faz-se uma análise qualitativa da sua distribuição nas regiões fisiográficas do Rio Grande do Sul, discutindose a diversidade de cada região associada a fatores ambientais e a amplitude de ocorrência dos táxons. Dez regiões fisiográficas do Rio Grande do Sul e quatro estações austro-sul-americanas constituíram quatorze unidades amostrais que foram comparadas entre si quanto à presença ou ausência das espécies da tribo Mutisieae, através da aplicação do índice de Jaccard, utilizando-se métodos de classificação e ordenação. Na análise de agrupamentos utilizou-se o critério "soma dos quadrados", e na ordenação o método utilizado foi o da "análise das coordenadas principais". Obtiveram-se dois grupos principais sensivelmente coincidentes com unidades biogeográficas reconhecidas por CABRERA & WILLINK (1980) e TAKHTAJAN (1986). Ficou evidente, ainda, a existência de um subgrupo de transição, geograficamente intermediário entre os dois grupos principais. São analisadas as afinidades entre as unidades amostrais baseadas em fatores ambientais. Faz-se uma reavaliação da área ancestral da família Asteraceae baseada nos resultados das análises deste estudo em relação àquela apresentada por BREMER (1992). Propõe-se que a área austro-sul-americana extra-andina situada desde a Patagônia até aproximadamente o paralelo de 30°S, no Rio Grande do Sul, passe a ser a região mais provavelmente vinculada à área ancestral da família Asteraceae. / The species of the tribe Mutisieae (Asteraceae) , sensu CABRERA (1977) occurring in Rio Grande do Sul, Brazil, w ere surveyed. Forty-eight species, four subspecies and two varieties were found, belonging to t welve genera and four subtribes. Descriptions of the tribe and genera as well as keys to the subtribes, genera and species are provided. An index with a list of the species and synonyms in alphabetical arder is displayed. Pampha/ea smithii, Perezia catharinensis and Trixis thyrsoidea are new geographical novelties to Rio Grande do Sul, whilst Chaptalia arechavaletae, Pamphalea missionum and Perezia squarrosa ssp. squarrosa are new botanical events to Brazil. A new species, Holocheilus monocephalus, is cited. Life forms, habitat and dispersai of the species are discussed and distributional patterns of the genera and species are established. Distribution maps of the species as well as a qualitative analysis of their distribution in the physiographical regions of Rio Grande do Sul are provided, with discussion of each region related to environmental features and geographical range of the species. Classification and ordenation techniques were used with application of Jaccard's coefficient to compare ten physiographical regions of Rio Grande do Sul and four austrosouth- american stands among themselves. "Sum-of-squares" was used in cluster analysis while "principal coordinates analysis" was applied in ordenation. Two main groups were obtained, strongly concurrent with biogeographical units recognized by CABRERA & WILLINK (1980) and TAKHTAJAN (1986). A transitional subgroup, geographically placed between the two main groups, was pointed out and cleared. Relationships among sampling units based on environmental features are analyzed. A new approach of ancestral area of the family Asteraceae is accomplished regarding BREMER'S (1992) analysis. lt is proposed that the austro-south-american extra-andean area situated since Patagonia to about 30°S in Rio Grande do Sul is the most likely region linked to ancestral area of the Asteraceae.
198

Redes neurais e algoritmos genéticos no estudo quimiossistemático da família Asteraceae / Neural Network and Genetic Algorithms in the Chemosystematic study of Asteraceae Family

Mauro Vicentini Correia 16 March 2010 (has links)
No presente trabalho duas metodologias da área de inteligência artificial (Redes Neurais e Algoritmos Genéticos) foram utilizadas para realizar um estudo Quimiossistemático da família Asteraceae. A família Asteraceae é uma das maiores famílias entre as Angiospermas, conta com aproximadamente 24.000 espécies. As espécies da família produzem grande diversidade de metabólitos secundários, entre os quais merecem destaque os terpenóides, poliacetilenos, flavonóides e cumarinas. Para um melhor entendimento da diversidade química da família construiu-se um Banco de Dados com as ocorrências de doze classes de metabólitos (monoterpenos, sesquiterpenos, sesquiterpenos lactonizados, diterpenos, triterpenos, cumarinas, flavonóides, poliacetilenos, benzofuranos, benzopiranos, acetofenonas e fenilpropanóides) produzidos pelas espécies da família. A partir desse banco três diferentes estudos foram realizados. No primeiro estudo, utilizando os mapas auto-organizáveis de Kohonen e o banco de dados químico classificado segundo duas das mais recentes filogenias da família foi possível realizar com sucesso separações de tribos e gêneros da família Asteraceae. Também foi possível indicar que a informação química concorda mais com a filogenia de Funk (Funk et al. 2009) do que com a filogenia de Bremer (Bremer 1994, 1996). No estudo seguinte, onde se objetivou a criação de modelos de previsão dos números de ocorrências das doze classes de metabólitos, utilizando o perceptron de múltiplas camadas com algoritmo de retropropagação de erro, o resultado foi insatisfatório. Apesar de em algumas classes de metabólitos a fase de treino da rede apresentar resultados satisfatórios, a fase de teste mostrou que os modelos criados não são capazes de realizar previsão para dados aos quais eles não foram submetidos na fase de treino, e portanto não são modelos adequados para realizar previsões. Finalmente, o terceiro estudo consistiu na criação de modelos de regressão linear utilizando como método de seleção de variáveis os algoritmos genéticos. Nesse estudo foi possível indicar que os monoterpenos e os sesquiterpenos são bastante relacionados biossinteticamente, também foi possível indicar que existem relações biossintéticas entre monoterpenos e diterpenos e entre sesquiterpenos e triterpenos / In this study two methods of artificial intelligence (neural network and genetic algorithms) were used to work out a Chemosystematic study of the Asteraceae family. The family Asteraceae is one of the largest families among the Angiosperms, having about 24,000 species. The species of the family produce a large diversity of secondary metabolites, and some worth mentioning are the terpenoids, polyacetylenes, flavonoids and coumarins. For a better understanding of the chemical diversity of the family a database was built up with the occurrences of twelve classes of metabolites (monoterpenes, sesquiterpenes, lactonizadossesquiterpenes, diterpenes, triterpenes, coumarins, flavonoids, polyacetylenes, Benzofurans, benzopyrans, acetophenones and phenylpropanoids) produced by species of the family. From this database three different studies were conducted. In the first study, using the Kohonen self-organized map and the chemical data classified according to two of the most recent phylogenies of the family, it was possible to successfully separatethe tribes and genera of the Asteraceae family. It was also possible to indicate that the chemical information agrees with the phylogeny of Funk (Funk et al. 2009) than with the phylogeny of Bremer (Bremer 1994, 1996). In the next study, which aims at creating models to predict the number of occurrences of the twelve classes of metabolites using multi-layer perceptron with backpropagation algorithm error, the result was found unsatisfactory. Although in some classes of metabolites the training phase of the network has satisfactory results, the test phase showed that the models created are not able to make prevision for data to which they were submitted in the training phase and thus are not suitable models for predictions. Finally, the third study was the creation of linear regression models using a genetic algorithm method of variable selection. This study could indicate that the monoterpenes and sesquiterpenes are closely related biosynthetically, and was also possible to indicate that there are biosynthetic relations between monoterpenes and diterpenes and between sesquiterpenes and triterpenes
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Estudo da estabilidade de produtos secos obtidos a partir de achyrocline satureioides (Lam.) DC. asteraceae / Stability study of spray dried powders from Achyrocline satureioides (Lam.) DC. Asteracea

Holzschuh, Maribete Homrich January 2008 (has links)
Dois extratos secos de Achyrocline satureioides (Lam.) DC., preparados a partir de soluções extrativas hidroetanólicas contendo 40 %(v/v) e 80 % (v/v) de etanol, denominados respectivamente de PS40 e PS80, foram avaliados no que concerne a sua estabilidade frente à temperatura e à luz. Para a avaliação de PS40 e PS80 frente à temperatura foram realizados estudos em condição de estresse (80 °C, 28 dias para PS40 e 14 dias para PS80), estudo de estabilidade acelerada (50 ± 2 °C/ 90 ± 5 UR, durante 3 meses para o PS40 e 40 ± 2 °C/ 75 ± 5 UR, durante 6 meses para o PS80) e estudo de longa duração, 12 meses (25 ± 2 °C e 60 ± 5 % UR, para PS40 e 30 ± 2 °C e 75 ± 5 % UR, para PS80). Para a avaliação da fotoestabilidade, PS40 e PS80 foram submetidos à radiação UV-C, durante 48 horas. Em todos os testes, a concentração dos constituintes fenólicos foi avaliada por CLAE, sendo a quercetina, luteolina, e 3-Ometilquercetina utilizadas como substâncias de referência, em ambos os extratos PS40 e PS80. A concentração de ácido caféico e das substâncias não identificadas P1, P2 e P3 foram avaliadas em PS40 e a concentração de P4, P5ab, P6, P7 e P8 em PS80. Os testes de estabilidade de longa duração de PS40 e PS80 revelaram que a concentração total dos constituintes fenólicos manteve-se dentro dos limites de ± 10 %, por 9 e 12 meses, respectivamente. Nestes extratos, as substâncias quercetina, luteolina e 3-Ometilquercetina, individualmente, mantiveram-se dentro dos limites de ± 10 %, por 12 meses. O estudo do PS40 e do PS80, em condições de estresse, revelou aumento do teor de quercetina a partir do segundo dia até 7 dias, mas com redução dos constituintes, ácido caféico e P3 no PS40 e P5ab e P8 no PS80. O produto contendo maior teor de quercetina obtido a partir do PS40, denominado PS40+, foi avaliado quanto a sua atividade antiedematogênica, apresentando, na terceira hora diferença significativa (p < 0,05; Student’s t-test) em relação ao controle negativo e, também, em relação ao controle positivo e na quarta hora, apresentou diferença significativa (p < 0,01; Student’s t-test) em relação ao grupo controle negativo. Não houve diferença significativa entre a atividade observada para o PS40 e PS40+ contendo o maior teor de quercetina (p < 0,05; Student’s t-test). No teste de estabilidade acelerado, para o PS40, o ácido caféico, a quercetina e a substância P3 reproduziram o comportamento instável, demonstrado no estudo em condições de estresse, as demais substâncias mantiveramse dentro dos limites de ± 10 %, durante 3 meses. Para o PS80 as substâncias P5ab e P8 tiveram seus teores reduzidos além do limite de ± 10 % e as demais substâncias mantiveram-se dentro deste limite, no teste de estabilidade acelerado, durante 6 meses. O estudo da fotoestabilidade revelou que PS40 e PS80 são estáveis por 48 horas, quando acondicionados em frasco de vidro âmbar ou transparente. No entanto, quando expostos à luz UVC em vidro de relógio, os constituintes fenólicos apresentaram-se instáveis. O estudo de cinética de degradação do PS80 demonstrou que as substâncias estudadas: quercetina, luteolina, 3-O-metilquercetina e P8 seguem cinética de reação de segunda ordem, quando submetidas à temperatura de 80 °C e por sua vez, seguem cinética de primeira ordem quando submetidas à radiação UV-C. Por meio de comparação com substância de referência e pelo teste de recuperação, foi possível identificar o ácido caféico, presente no PS40. Utilizando a cromatografia em coluna, foram isoladas as substâncias P1, P2, P3 e 3-O-metilquercetina a partir do PS40. A partir de PS80 foi isolada, por cromatografia em camada delgada preparativa, e identificada a substância P8. A elucidação estrutural da substância P8 (PS80) e a correspondente P3 (PS40) revelou tratar-se da 4,2’,4’’,2’’’-tetraidróxi-6’,6’’’-dimetóxi-4’- O-4’’’- bichalcona. / Thermal and photo stabilities of two Achyrocline satureioides spray dried powders, SDP40 and SDP80, were evaluated. These spray dried powders were, respectively, prepared from 40 % (v/v) or 80 % (v/v) ethanol extractive solution of the inflorescences. The thermal stability test conditions for SDP40 and SDP80 were the stress testing (80 °C, 28 days for SDP40 e 14 days for SDP80), the accelerated term testing (50 ± 2 °C/ 90 ± 5 RH, 3 months, for SDP40 and 40 ± 2 °C/ 75 ± 5 RH, 6 months, for SDP80) and the long term testing (25 ± 2 °C / 60 ± 5 % RH, for SDP40 and 30 ± 2 °C /75 ± 5 % RH for SDP80). In the photo stability study SDP40 and SDP80 were submitted to UV-C radiation, for 48 hours. The long term testing for SDP40 and SDP80 revealed that the total concentration of phenolic constituents remained within the limit of ± 10 %, for 12 month, in both extracts. When SDP40 and SDP80 were submitted to stress testing, at the final of the second or the seventh day, respectively, it was observed an anomalous increase in the quercetin concentration; in contrast, caffeic acid and P3 in SDP40 and P5ab and P8 in SDP80 presented its concentrations decreased. The product with higher amount of quercetin, obtained from SDP40, designed SDP40+, was evaluated regarding to antiedematogenic activity, showing at the third hour significant difference (p < 0,05; Student’s t-test) related to the negative control, as well as to the positive control. At the forth hour it showed significant difference (p < 0,01; Student’s t-test), related to the negative control. Between, SDP40 and SDP40+ it was not observed significant difference (p < 0,05; Student’s t-test). In the accelerate term testing, for SDP40, caffeic acid, quercetin and substance P3, reproduced the unstable behavior observed in the stress testing; the other phenolic constituents remained within the limit of ± 10 %, for 3 months. For SDP80 accelerated term testing, the substances P5ab and P8 degradated below the limit of ± 10 % its concentration; the other phenolic constituents remained with its concentrations within the limit, for 6 months. The photostability study revealed that SDP40 and SDP80 were stable for 48 hours, when they were conditioned in amber or transparent flask. However, when they were conditioned in open-dish, the phenolics showed unstable behavior. The kinetic of degradation study revealed that the polyphenols quercetin, luteolin, 3-O-methylquercetin and P8 followed second order reaction, when submitted to temperature (80 °C), and first order reaction when submitted to UV-C radiation. Regarding the identification of the phenolic constituents in SDP40 or SDP80, caffeic acid was identified in SDP40 by comparison with the reference substance. Column chromatography was used to isolate, from SDP40, the substances P1, P2, P3 and 3-O-methylquercetin. Preparative thin layer chromatography was used to isolate, from SDP80, the substance P8, which was identified. The structural elucidation of substance P8 (SDP80) and the corresponding P3 (SDP40) revealed that it chemical molecular formule is 4,2’,4’’,2’’’-tetrahydroxy-6’,6’’’-dimethoxy-4’-O-4’’’- bichalcone, for the first time reported to Achyrocline satureioides.
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Autoecologia de Baccharis platypoda DC. (Asteraceae): distribui??o espacial, fenologia e herbivoria

Fonseca, Darliana da Costa 27 July 2012 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-23T13:49:38Z No. of bitstreams: 5 1.pdf: 5282104 bytes, checksum: 5079ffdcbf2b7fa8508a090d60e3bc93 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-23T17:37:51Z (GMT) No. of bitstreams: 5 1.pdf: 5282104 bytes, checksum: 5079ffdcbf2b7fa8508a090d60e3bc93 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) / Made available in DSpace on 2015-01-23T17:37:51Z (GMT). No. of bitstreams: 5 1.pdf: 5282104 bytes, checksum: 5079ffdcbf2b7fa8508a090d60e3bc93 (MD5) license_url: 52 bytes, checksum: 3d480ae6c91e310daba2020f8787d6f9 (MD5) license_text: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) license.txt: 2109 bytes, checksum: aa477231e840f304454a16eb85a9235f (MD5) Previous issue date: 2012 / O presente trabalho teve como objetivo compreender alguns par?metros acerca da hist?ria natural da esp?cie Baccharis platypoda, um arbusto dioico pertencente ? fam?lia Asteraceae, com indiv?duos masculinos e femininos que apresentam dimorfismo sexual e habitam ?reas de campo rupestre, campos e bordas de matas ciliares. Para compreender alguns pontos sobre sua autoecologia, foram analisadas a distribui??o espacial, a fenologia e as intera??es ecol?gicas entre a esp?cie e insetos end?fagos. O estudo foi realizado em tr?s ?reas pertencentes ? Universidade Federal dos Vales do Jequitinhonha e Mucuri ? UFVJM, localizados no Campus JK, pr?ximo ao C?rrego do Soberbo. A ?rea ? composta por mosaicos de vegeta??o, onde h? predom?nio de afloramentos rochosos e campos ?midos. Em cada ?rea, foram selecionados dez indiv?duos de B. platypoda, sendo cinco indiv?duos de cada sexo, onde, por um per?odo de um ano (set./2010 a set/2011) foram feitas visitas quinzenais para a observa??o dos est?gios fenol?gicos. Nesse per?odo, foram coletados cap?tulos quinzenalmente para cria??o de insetos end?fagos em recipientes vedados com algod?o e que, ap?s a eclos?o, foram conservados em ?lcool 70%; os cap?tulos foram dissecados para an?lise dos danos ?s estruturas florais. Para o estudo da distribui??o espacial, todos os indiv?duos foram localizados por meio das coordenadas x e y de cada planta, com altura ?30 cm atrav?s das dist?ncias, obtidas com uma trena, e identificados quanto ao sexo ou como jovem, pela aus?ncia de estruturas reprodutoras. O padr?o de distribui??o espacial foi determinado atrav?s da Fun??o K de Ripley univariada e bivariada, enquanto que os padr?es fenol?gicos foram determinados atrav?s da an?lise de intensidade de Fournier, correla??o de Spearman e an?lise circular. O padr?o de herbivoria foi analisado atrav?s da an?lise de regress?o linear, teste de Kruskal-Wallis e an?lise de agrupamento pelo m?todo de Two-Way-joining. Foi aplicado o teste de qui-quadrado para o estudo de distribui??o espacial e para o padr?o de herbivoria. Baccharis. platypoda apresentou padr?o agregado com varia??es em escalas diferentes para jovens e adultos e semelhan?a espacial entre indiv?duos de ambos os sexos. No entanto, a independ?ncia espacial entre os indiv?duos da esp?cie se mostrou uma constante. A fenologia reprodutiva da esp?cie esteve associada a algumas vari?veis ambientais (precipita??o e temperatura), enquanto que a fenologia vegetativa, de modo geral, apresentou-se relacionada ? fenologia reprodutiva das esp?cies. Insetos end?fagos apresentaram prefer?ncias quanto ao sexo e est?gio fenol?gico dos cap?tulos, havendo maior preda??o em cap?tulos masculinos e em est?gios mais desenvolvidos. Assim, a esp?cie apresentou correla??o entre a sua distribui??o espacial, os est?gios fenol?gicos (principalmente a fenologia reprodutiva) e os padr?es de ataque de insetos end?fagos, sugerindo a utiliza??o deste conhecimento na elabora??o de poss?veis estrat?gias de preserva??o e manejo. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2012. / ABSTRACT This study has as its main goal the understanding of some parameters on the natural history of the Baccharis platypoda species, a unisexual bush belonging to the Asteraceae subdivision, in which both male and female single organisms present sexual dimorphism inhabiting in rupestrian field areas, fields and woodland ciliary edges. In order to have a better understanding on some issues of its auto ecology, spatial, phenology, and ecological interactions between the species, endophage insects have been analyszed. This study took place in three areas belonging to UFVJM - Universidade Federal dos Vales do Jequitinhonha e Mucuri, situated at the JK Campus, by the Soberbo Stream. The area is composed of a miscellany vegetation with the prevalence of protruding rocks and wet fields. Ten B. platypoda organisms were selected from each one of these areas, five from each gender. During one year from september, 2010 to september, 2011 biweekly inspections for the watch of phenological stages were made. During this period of time, biweekly chapters for the production of endophage insects were gathered in cotton sealed containers preserved in alcohol after emergence. The chapters were dissected for the analysis of possible floral composition damages. For the spatial distribution study all the organisms were found through the use of X and Y reference point of each plant with height of 30 cm or over, tape measured, identified as to gender or youth due to absence of reproductive compositions. The spatial distribution pattern was established through the use of Ripley's K Function univariate and bivariate, whereas the phenological patterns were determined through the analysis of Fournier intensity, Spearman's corelation and circular analysis. The herbivory pattern was analyzed through the linear regression analysis, Kruskal-Wallis's test, and the Two-Way-joining method. The chi-square test was used for the study of spatial distribution and for the herbivory pattern. Baccharis. platypoda showed aggregate pattern with variations in different ranges both for young and adults, and also spatial likeness with organisms of both genders. However, there was a steady spatial independence among the organisms of the species. The species reproductive phenology was associated to some environmental variations (precipitation and temperature), whereas the vegetative phenology as a whole was related to the reproductive species phenology. Endophage insects showed preferences as to genger and phonological chapter stages; there was more predation in male chapters in more developed stages. Thus, the species presented correlation among its spatial distribution, phenological stages (mainly the reproductive phenology) and the patterns of phenological insects, suggesting the use of this knowledge in the elaboration of possible strategies for preservation and management.

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