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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.
331

Determinantes do consumo de frutas, legumes e verduras em adultos residentes no município de São Paulo / Determinants of fruit and vegetable intake in adults living in São Paulo City.

Figueiredo, Iramaia Campos Ribeiro 14 August 2006 (has links)
Introdução: A incidência de doenças crônicas não transmissíveis (DCNT) vem aumentando em todo o mundo. Estudos comprovam que o consumo de frutas, legumes e verduras (FLV) reduzem a incidência de DCNT na população Objetivo: Avaliar os determinantes do consumo de FLV em adultos residentes no município de São Paulo Metodologia: É um estudo transversal, abrangendo 1267 mulheres e 855 homens, com idade igual ou superior a 18 anos. A análise de regressão linear foi baseada no modelo hierárquico de fatores associados ao consumo de FLV. As variáveis foram agrupadas em categorias hierárquicas, abrangendo dos fatores distais aos proximais. Essas categorias foram, nessa ordem, sócio-demográfica, comportamental e de consumo alimentar. Resultados: Para ambos os sexos, verificou-se que as seguintes variáveis estavam diretamente associadas ao consumo de FLV: idade e anos de estudo, na categoria sócio-demográfica; prática de atividade física no lazer e ter feito dieta no último ano, na categoria comportamental e consumo de peixe na categoria de consumo alimentar. A densidade domiciliar mostrou-se inversamente associada ao consumo de FLV em ambos os sexos. Somente para as mulheres ser ou já ter sido casada foi diretamente associado ao consumo de FLV e ser fumante mostrou-se inversamente associado. O consumo de alimentos que indicam um padrão de consumo não saudável como açúcares e carne vermelha com gordura mostrou-se inversamente associado ao consumo de FLV em ambos os sexos. Conclusão: O consumo de FLV e seus determinantes são diferentes para homens e mulheres, sendo a maior freqüência de consumo ocorre no sexo feminino. / The burden of noncommunicable diseases (NCD) increases in the whole world. Studies prove that consumption do fruits and vegetables (FV) reduce the incidence of NTCD in the population. The present study aims to evaluate by telephones interviews the determinants of Fruit and vegetable's intake in adults living in São Paulo City. This is a cross-sectional study, ranging over 1267 women and 855 men, aged 18 years old or more. Multiple linear regression analysis was based on a hierarchical model of factors associated with FV intake. The variables were grouped into a hierarchy of categories, ranging from distal determinants to proximate ones. These categories included, in this order, socio-demographic, behavioral and food consumption. For both gender, we found that the following variables were directly associated with FV intake: age and years of study, in the socio-demographic category, physical activity in leisure time and have been on a diet in the last year, in the behavioral category and fish consumption in the nutritional category. The domiciliary density was inversely associated with FLV consumption for both genders. Only for women marital status was directly associated with FV intake and tobacco use were inversely associated. The dietary intake of food that indicates an unhealthy diet, like sugar and read meat with fat were inversely associated with FV intake for both gender. Consumption of FV and their determinants are different for man and women and the major consumption occurs with women.
332

\"Valor nutricional de espécies arbóreo-arbustivas nativas da caatinga e utilização de tratamentos físico-químicos para redução do teor de taninos\" / Nutritional value of plants from caatinga and the use of physical and chemical treatments to reduce tannin levels

Nozella, Eduardo Fernando 21 November 2006 (has links)
As espécies nativas do semi-árido nordestino constituem uma importante fonte de proteína para o rebanho da região, especialmente durante a estação seca. Contudo, a composição química dessas plantas, especialmente teores de fibra, proteína bruta e compostos secundários, apresenta variações ao longo do ano, em função do ciclo fenológico. O conteúdo de taninos nas plantas pode variar de acordo com as condições climáticas e geográficas. Objetivou-se com o presente estudo: (i) avaliar a composição química de plantas de três Estados do nordeste brasileiro; (ii) verificar o efeito dos taninos na produção de gases; (iii) testar métodos de detanificação, para melhorar o valor nutritivo dessas plantas. O estudo foi dividido em três capítulos. No primeiro, foram avaliadas espécies nativas do semi-árido de Pernambuco, Bahia e Ceará por meio de análises químicas e técnica de produção de gases: angico - Anadenanthera macrocarpa, aroeira - Astronian urundeuva, catingueira - Caesalpinia bracteosa, jucazeiro - Caesalpinia ferre, jurema preta - Mimosa hostilis, leucena - Leucaena leucocephala, malva branca - Sida cordifolia, maniçoba - Manihot pseudoglaziovii, pau branco - Auxemma oncocalyx e sabiá - Mimosa caesalpinifolia. No segundo e terceiro capítulos, foram testados métodos de secagem e aplicação de soluções alcalinas (cinzas de madeira e hidróxido de cálcio) e de polietileno glicol para redução dos efeitos dos taninos. Os resultados obtidos pela avaliação da composição química nas três regiões demonstraram que as espécies estudadas representam uma importante reserva de forragem para os ruminantes e que o teor de compostos fenólicos deve ser monitorado, uma vez que algumas dessas espécies apresentam altos teores destes compostos. Os métodos de secagem testados não foram eficientes para minimizar a ação dos taninos e os tratamentos com soluções alcalinas e com PEG foram eficazes para reduzir a concentração dos taninos, quando medida pela análise química. O tratamento com PEG resultou uma resposta na diminuição da atividade dos taninos no bioensaio / The typical vegetation of the semi-arid region of northeast Brazil is considered an important source of protein for the animals, mainly during the dry season. However, the chemical composition of the plants, as fiber, protein and secondary compounds change during the year with the different stage of the plants. The tannin concentration varies according to climatic and geographic conditions. The aims of this study were: (i) to evaluate the chemical composition of plants of three regions in the northeast Brazil; (ii) to verify the effect of tannins on gas production; (iii) to use detanification methods to improve the nutritional value of those plants. The study contains three chapters. In the first chapter, the following species of plants from Pernambuco, Bahia and Ceara were evaluated by chemical analysis and gas production: angico - Anadenanthera macrocarpa, aroeira - Astronian urundeuva, catingueira - Caesalpinia bracteosa, jucazeiro - Caesalpinia ferre, jurema preta - Mimosa hostilis, leucena - Leucaena leucocephala, malva branca - Sida cordifolia, manicoba - Manihot pseudoglaziovii, pau branco - Auxemma oncocalyx and sabia - Mimosa caesalpinifolia. In the second and third chapters various detanification methods were tested, as drying processes and application of alkaline solutions (wood ash and calcium hydroxide) and polyethylene glycol application. The chemical analysis showed that all the plants studied could be used as animal feed, but the phenolics contents could be a detrimental factor and should be monitored. The drying methods were not efficient to minimize tannin effects as showed using the gas production. The treatment with wood ash, calcium hydroxide and polyethylene glycol resulted in a decrease of tannins concentration, but only polyethylene glycol treatment decreased tannins activity during the gas production.
333

Otimização do método lignina brometo de acetila na determinação do teor de lignina em plantas forrageiras e comparação com os métodos lignina detergente ácido e lignina Klason / Improving the acetyl bromide lignin method in determining lignin content in forages and comparison with the methods acid detergent lignin and Klason lignin

Santamaria, Marcos Felipe Zuñiga 15 February 2016 (has links)
Técnicas analíticas empregadas para a quantificação do teor de lignina em plantas forrageiras, atualmente em uso, são questionáveis quanto às suas acurácias. O método lignina detergente ácido (LDA), que é um dos métodos mais utilizado em Ciência Animal e Agronomia, apresenta algumas falhas, particularmente devido à parcial solubilização da lignina durante a preparação da fibra em detergente ácido (FDA). A lignina Klason (LK), outro método muito usado, apresenta o inconveniente de mensurar a proteína da parede celular como sendo lignina. Em ambos os procedimentos recomenda-se também mensurar cinzas nos resíduos de lignina. A quantificação da concentração de lignina pelo método espectrofotométrico lignina brometo de acetila (LBA) vem ganhando interesse de pesquisadores no Brasil e no exterior. Nesta metodologia, a lignina da planta contida na preparação parede celular (PC) é solubilizada numa solução a 25% de brometo de acetila em ácido acético e a absorbância mensurada é com luz UV a 280 nm. O valor da absorbância é inserido numa equação de regressão e a concentração de lignina é obtida. Para que esta técnica analítica seja mais aceita pelos pesquisadores, ela deve ser, obviamente, convincente e atrativa. O presente trabalho analisou alguns parâmetros relacionados à LBA em 7 gramíneas e 6 leguminosas, em dois estádios de maturidade. Dentre as diferentes temperaturas de pré-secagem, os resultados indicaram que os procedimentos de 55°C com ventilação e liofilização podem ser utilizados com a mesma eficácia. As temperaturas de 55°C sem ventilação e 80°C sem ventilação não são recomendadas, pois aumentaram os valores de FDA e LDA, possivelmente devido ao surgimento de artefatos de técnica como os compostos de Maillard. No método LBA os valores menores das amostras de leguminosas chamaram a atenção e colocaram em questão se a lignina destas plantas seria menos solúvel no reagente brometo de acetila. Dentre algumas alterações na metodologia da técnica LBA, a utilização do moinho de bolas (para diminuir o tamanho particular) nas amostras de PC não mostrou efeito; a hipótese era melhorar a solubilização da lignina usando partículas menores. O uso de um ultrasonicador, que aumenta a vibração das moléculas e assim, facilitaria a solubilização da lignina no reagente brometo de acetila, melhorou a solubilização da lignina em cerca de 10%, tanto nas gramíneas como nas leguminosas. Foi acoplado um ensaio biológico como referência, a degradabilidade in vitro da matéria seca (DIVMS); e como a lignina está intimamente associada à estrutura fibrosa da parede celular, também foi feito um ensaio de degradabilidade in vitro da fibra em detergente neutro (DIVFDN). Os resultados confirmaram o efeito da maturidade, reduzindo a degradabilidade nas plantas mais maduras, e que o teor de lignina de leguminosas é realmente inferior ao de gramíneas. Os resultados de degradabilidade apresentaram coeficientes de correlação mais elevados com o método LBA, quando foi empregada a técnica do ultrasom; o método LK mostrou os menores coeficientes. Também testou-se, com sucesso, a utilização da FDN, como preparação fibrosa, ao invés de PC. A razão é simples: enquanto que a FDN é amplamente conhecida, a preparação PC não o é. Inquestionável que esta manobra facilitará substancialmente a divulgação desse método, tornando-a mais aceitável pela comunidade científica / Analytical techniques employed to quantify lignin content in forages, currently in use, are questionable as to their accuracies. The method acid detergent lignin (ADL), which is one of the most used method in Animal Science and Agronomy, has some flaws, due to the partial lignin solubilization during the preparation of acid detergent fiber (ADF). The Klason lignin method (KL), another analytical procedure commonly used, has the drawback of measuring the cell wall protein as lignin. In both procedures also are recommended to measure ash content in the lignin residues. Quantification of lignin concentration by the spectrophotometric acetyl bromide lignin method (ABL) has been gaining interest from researchers in Brazil and abroad. In this methodology, the lignin contained in the plant cell wall preparation (CW) is solubilized in a 25% acetyl bromide in acetic acid solution and the absorbance is measured with UV light at 280 nm. The absorbance value is inserted in a regression equation and the concentration of lignin is obtained. For this analytical technique be better accepted by researchers, it must be, obviously, convincing and attractive. This study analyzed some LBA-related parameters in 7 grasses and 6 legumes in two stages of maturity. Among the different temperatures of pre-drying, the results indicated that the procedures at 55°C with ventilation and lyophilization can be used just as effectively. Temperatures of 55 and 80 both without ventilation are not recommended because they increased ADF and ADL values, possibly due to the emergence of technical artifacts such as the compounds of Maillard. The ABL method yielded lower values for legume samples which called into question if the lignin of these plants is less soluble in the acetyl bromide reagent. Among some changes studied in the ABL technique it was the utilization of ball milling in the PC samples, which showed no effect; the hypothesis was to reduce the particle size and thus improve the solubilization of lignin. The use of an ultrasonicator, which increases the vibration of molecules and possibly allowing better solubilization of lignin in the acetyl bromide reagent improved lignin solubilization by about 10%, both in grasses. As a reference, an in vitro dry matter degradability (IVDMD) was conducted. Because lignin is closely linked to the fibrous structure of the cell wall, an in vitro neutral detergent fiber degradability (IVNDFD) test of. Results confirmed the effect of maturity, reducing degradability as the plants matured, and that concentration of lignin is lower in legumes than in grasses. The degradability results showed higher correlation coefficients with the ABL method when the ultrasonicator was used; the KL method showed the lowest coefficients. We also tested, successfully, the use of NDF as a fiber preparation, instead of crude CW. While NDF is widely known, CW preparation is not. This maneuver will substantially facilitate the dissemination of this method, making it more acceptable to the scientific community
334

Impacto de intervenção para promoção do consumo de frutas e hortaliças em empresas cadastradas no Programa de Alimentação do Trabalhador / Impact of an intervention to promote consumption of fruits and vegetables in companies participating in the Worker Food Program

Daniel Henrique Bandoni 09 September 2010 (has links)
Introdução: O baixo consumo de frutas e hortaliças é um importante fator de risco para diversas doenças crônicas e obesidade. Na população brasileira, o consumo destes alimentos é tradicionalmente abaixo das recomendações internacionais. Dentro deste cenário, os locais de trabalho vêm atraindo cada vez mais interesse como ambientes propícios para o desenvolvimento de ações de promoção de alimentação saudável direcionadas à população adulta. Objetivo: Avaliar o impacto de uma intervenção para aumentar a oferta e o consumo de frutas e hortaliças em empresas cadastradas no Programa de Alimentação do Trabalhador. Métodos: Trata-se de um estudo de intervenção com amostra de 29 empresas divididas em dois grupos: intervenção (n=15) e controle (n=14). Avaliou-se uma amostra de trabalhadores em todas as empresas participantes do estudo para verificar os efeitos da intervenção sobre o consumo de frutas e hortaliças. A intervenção foi baseada no modelo ecológico de promoção de saúde, teve quatro etapas com duração total de seis meses. A coleta de dados ocorreu em dois momentos: antes e após a intervenção. O efeito da intervenção foi investigado por meio de dois indicadores: oferta em gramas de frutas e hortaliças nas refeições servidas nas empresas e o consumo em gramas destes alimentos pelos trabalhadores. De forma secundária, avaliou-se o impacto da intervenção sobre a oferta de energia, macronutrientes e fibras nas refeições. Para avaliar o efeito da intervenção sobre a oferta de alimentos e nutrientes nas refeições, realizou-se comparação entre os grupos intervenção e controle e a comparação intra-grupos antes e após a intervenção. Para o consumo dos trabalhadores, utilizou-se análise de regressão linear para avaliar a mudança no consumo no grupo intervenção após a intervenção. Resultados: A oferta de frutas e hortaliças aumentou de forma significativa após a intervenção nos cardápios oferecidos pelas empresas no grupo intervenção, cerca de + 49g, enquanto não houve variação no grupo controle. Também se observaram efeitos positivos na oferta de fibras e redução na oferta de gorduras. A intervenção também aumentou o consumo de frutas e hortaliças entre os trabalhadores nas refeições oferecidas pelas empresas, o aumento médio foi de 11g, após ajustes pelas variáveis sociodemográficas dos trabalhadores. Conclusão: A intervenção apresentou impacto positivo sobre a oferta e consumo de frutas e hortaliças no ambiente de trabalho / Introduction: The low consumption of fruits and vegetables is an important risk factors for several chronic diseases and obesity. In the Brazilian population the consumption of these foods is traditionally lower of international recommendations. In this context, the workplace environment is considered to promote healthy food, comprising large portion of the adult population. Objective: To evaluate the impact of an intervention to increase the availability and consumption of fruits and vegetables in companies participating in the Worker Food Program. Methods: It was a randomized intervention involving a sample of 29 companies divided in two groups: intervention (n=15) and control (n=14). A sample of workers in all companies participating in the study was evaluated in order to assess the effects of intervention on the consumption of fruits and vegetables. The intervention was based on the ecological model of health promotion, with 4 different stages for 6 months. Data collection occurred in two stages, before the intervention and after intervention. The effect of the intervention was investigated using two indicators: the availability in grams of fruit and vegetables in meals served in companies and consumption in grams of food by employees. Secondarily, the impact of intervention on the availability of energy, macronutrients and fiber in meals was assessed. It was made a comparison between the intervention and control groups and intra-group comparison before and after intervention to evaluate the effect of intervention on the availability of food and nutrients in meals. For the consumption of workers we used linear regression analysis to evaluate the change in consumption in the intervention group after the intervention. Results: The availability of fruits and vegetables in the meals offered by companies in the intervention group increased about +49g, while no changes in the control group. Also, it was observed positive effects on the availability of fiber and fat reduction in meals. The intervention also increased fruits and vegetables consumption among workers, the mean increase was 11g, after adjusting for sociodemographic variables of workers. Conclusion: The intervention has presented a positive impact on the availability and consumption of fruits and vegetables in the workplace
335

Utilização de rizóbios e fungo micorrízico para implantação de um sistema agroflorestal no semiárido pernambucano / Use of rhizobia and mycorrhizal fungi to implement an agroforestry system in semi-arid Pernambuco

BARBOSA, Marisângela Viana 28 February 2013 (has links)
Submitted by (lucia.rodrigues@ufrpe.br) on 2016-12-22T13:48:31Z No. of bitstreams: 1 Marisangela Viana Barbosa.pdf: 782275 bytes, checksum: e0f60df2d84c34d378476085357848db (MD5) / Made available in DSpace on 2016-12-22T13:48:32Z (GMT). No. of bitstreams: 1 Marisangela Viana Barbosa.pdf: 782275 bytes, checksum: e0f60df2d84c34d378476085357848db (MD5) Previous issue date: 2013-02-28 / The use of agroforestry systems (SAF’s) has been an alternative to reduce environmental impacts and assist in the recovery of degraded areas. In this context, the aim of this study was to evaluate the effect of inoculation with rhizobia strains and arbuscular mycorrhizal fungi associated with legume trees intercropped with cowpea [Vigna unguiculata (L.) Walp] in SAF's. Seedling production was carried out in the greenhouse of UFRPE / UAST. Using seeds of leucaena (Leucaena leucocephala (Lam.) de Wit) and mimosa (Mimosa caesalpiniifolia Benth.). The seeds were disinfected and inoculated with strains of native rhizobia (S1LRJ and S1003) and recommended by EMBRAPA (Semia 6069 and BR 3405) for leucaena and mimosa respectively, sown in containers with soil. After 100 days of emergency were planted in an experimental area of IFPE, Campus Belo Jardim, PE. The plot was composed of eight trees with spacing of 4.0 x 2.5 m, half inoculated with Gigaspora margarita. The experimental design was in randomized block (DBC) in factorial 2x2x4(with and without mycorrhiza, native and recommended rhizobia, and four times of assessment) with 3 blocks in split plot, each species being assessed separately. Evaluations were performed at implantation, at 60, 120 and 180 days by determining: plant height (AP), stem diameter of plants (DC) and the ratio of the height and diameter (RAPDC). At 60 days, was planted cowpea (Vigna unguiculata (L.) Walp.) Cultivar IPA 206, inoculated with strain (BR 3267) at a spacing of 0.5 x 0.5 m. Assessing the effect of different treatments on beans in DBC with factorial 4x2x2 (two trees with native and recommended rhizobia, with and without mycorrhiza and with and without rhizobia strains to cowpea) in split split plot. Determined shoot dry mass (MSPA), yield (kg ha-1), shoot total N, soil microbial biomass (BMS) and organic carbon. Data were subjected to analysis of variance and means were compared by Tukey test at 5% probability. Was observed highest developing in mimosa seedlings, with no isolated effect of the treatments, occurring interaction to G. margarita and Rhizobium S1003. There wasno influence of treatments for yield, total N and MSPA of cowpea and soil organic C and BMS. This study shows the importance of understanding the interactions micro-organism/plant to optimize the application of biotechnology in crop production. / A utilização de sistemas agroflorestais (SAFs), tem sido uma alternativa para reduzir os impactos ambientais e auxiliar na recuperação de áreas degradadas. Neste contexto, o objetivo deste estudo foi avaliar o efeito da inoculação de estirpes de rizóbios e fungos micorrizicos arbusculares associados a leguminosas arbóreas consorciadas com o feijão caupi [Vigna unguiculata (L.) Walp] em SAF’s. A produção de mudas foi realizada no viveiro da UFRPE/UAST. Utilizando sementes de leucena (Leucaena leucocephala (Lam.) de Wit) e sabiá (Mimosa caesalpiniifolia Benth.). As sementes foram desinfetadas e inoculadas com estirpes de rizóbios nativos (S1LRJ e S1003) e recomendados pela EMBRAPA (Semia 6069 e BR 3405) para leucena e sabiá respectivamente, semeadas em recipientes com solo. Após 100 dias de emergência foram plantadas em uma área experimental do IFPE, Campus de Belo Jardim, PE. A parcela foi composta por 8 arbóreas com espaçamento de 4,0 x 2,5 m, metade inoculada com Gigaspora margarita. O delineamento foi em blocos casualisados (DBC) em fatorial 2x2x4 (com e sem micorriza, rizóbios nativos e recomendados, e quatro épocas de avaliação) 3 blocos, em parcelas subdivididas, sendo avaliada cada espécie isoladamente. As avaliações foram realizadas na implantação, aos 60, 120 e 180 dias determinando: altura de planta (AP), diâmetro do colo das plantas (DC) e a relação da altura a planta pelo diâmetro RAPDC. Aos 60 dias, foi plantado o caupi (Vigna unguiculata (L.) Walp.) cultivar IPA 206, inoculada com a estirpe (BR 3267) em um espaçamento de 0,5 x 0,5 m. Avaliando o efeito dos diferentes tratamentos sobre o feijão em DBC com fatorial 4x2x2 (duas arbóreas, com e sem micorriza e com e sem estirpes de rizóbios) em parcela subsudivididas. Determinou-se a massa seca da parte aérea (MSPA), produtividade (Kg ha-1), N total da parte aérea, biomassa microbiana do solo (BMS) e carbono orgânico. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5% probabilidade. Foi observado um maior desenvolvimento para as mudas de sabiá, não havendo efeito isolado dos tratamentos, observando-se interação para G. margarita e rizóbio S1003. Não houve influência dos tratamentos para produtividade, N total e MSPA do caupi e para o solo C orgânico e BMS. Este estudo mostra a importância do conhecimento das interações micro-organismo/planta, para otimizar a aplicação da biotecnologia na produção vegetal.
336

Influência do processamento e do processo digestivo in vitro na bioacessibilidade de compostos fenólicos do feijão comum / Influence of processing and in vitro digestive process on the bioaccessibility of phenolic compounds of common beans

Samara dos Santos Harada Padermo 23 May 2017 (has links)
O feijão tem destaque por ser base da alimentação brasileira juntamente com o arroz, fornecendo nutrientes essenciais ao desenvolvimento humano, como proteínas e minerais. Os benefícios do consumo de feijão vão além do fornecimento de nutrientes essenciais, já que esta leguminosa tem se destacado também por seu potencial benéfico à saúde, apresentando efeito antioxidante e antimutagênico. Estes efeitos têm sido associados à presença de compostos bioativos, em especial os compostos fenólicos. O processamento térmico é essencial para o consumo destes grãos, entretanto, pode causar modificações nos seus fitoquímicos, seja na composição ou na concentração. Além disso, é preciso ressaltar que nem todo conteúdo de polifenóis, ou de qualquer nutriente, é absorvido e aproveitado integralmente pelo organismo, é preciso compreender como o processo digestivo influencia a bioacessibilidade destes compostos. Sendo assim, este trabalho teve como objetivo avaliar a influência de diferentes formas de tratamento térmico sobre os principais compostos fenólicos (mais relevantes de acordo com a literatura), conteúdo de fenólicos totais e atividade antioxidante dos feijões carioca e preto (variedades mais consumidas no Brasil), além de verificar a influência do tratamento térmico e do processo digestivo simulado in vitro sobre a concentração e a bioacessibilidade dos compostos fenólicos encontrados nas amostras. Foram avaliados grãos crus; grãos macerados em água por 12 horas; grãos cozidos em panela aberta com ou sem a água de maceração; grãos cozidos sob pressão com ou sem a água de maceração. Foram realizadas análises de compostos fenólicos totais, atividade antioxidante pelos métodos de DPPH, ABTS e ORAC, além da análise cromatográfica dos principais compostos fenólicos dos feijões. As amostras cozidas foram submetidas à digestão in vitro e analisadas quanto ao seu conteúdo de compostos fenólicos. O tratamento térmico promoveu a liberação de compostos fenólicos ligados a matriz, aumentando assim, o conteúdo de polifenóis livres acompanhado do aumento do potencial antioxidante em relação ao grão cru. A utilização da água de maceração e de pressão durante a cocção preservou maior conteúdo de polifenóis em relação aos tratamentos onde a água foi descartada e aos tratamentos em panela aberta. A avaliação da bioacessibilidade permitiu verificar que o processo digestivo tem influência na concentração dos polifenóis, sendo que a etapa duodenal, em especial, foi marcada por redução na concentração dos compostos fenólicos analisados. As amostras em que a água de maceração foi utilizada na cocção tinham maior conteúdo de polifenóis livres, entretanto, este conteúdo não estava totalmente bioacessível. Sendo assim, o descarte da água de maceração e a utilização de pressão para cocção são os procedimentos mais indicados para preservação dos compostos fenólicos da fração bioacessível. Neste estudo foi evidenciado que o tratamento térmico, a matriz e o processo digestivo in vitro têm influência sobre os compostos fenólicos da fração bioacessível. / Beans are highlighted as being the basis of the Brazilian diet along with rice, providing essential nutrients for human development, such as proteins and minerals. The benefits of bean consumption go beyond the supply of essential nutrients, since this legume has also been highlighted by its beneficial potential to health, showing antioxidant and antimutagenic effect. These effects have been associated with the presence of bioactive compounds, especially the phenolic compounds. Thermal processing is essential for the consumption of these grains, however, it can cause changes in their phytochemicals, either in composition or in concentration. In addition, it should be noted that not all polyphenol content, or any nutrient, is fully absorbed and utilized by the body, so it is necessary to understand how the digestive process influences the bioaccessibility of these compounds. Therefore, the objective of this work was to evaluate the influence of different forms of thermal treatment on the main phenolic compounds (more relevant according to the literature), total phenolic content and antioxidant activity of the carioca and black beans (most consumed varieties in Brazil), in addition to verifying the influence of the heat treatment and simulated in vitro digestive process on the concentration and bioaccessibility of the phenolic compounds found in the samples. Raw grains; grains macerated in water for 12 hours; grains cooked in an open pan with or without soaking water; grains cooked under pressure with or without soaking water were evaluated. Analyzes of the total phenolic compounds, antioxidant activity by the DPPH, ABTS and ORAC methods, as well as the chromatographic analysis of the main phenolic compounds of the beans were performed. Cooked samples were submitted to in vitro digestion and analyzed for their content of phenolic compounds. The heat treatment promoted the release of phenolic compounds bound to the matrix, thus increasing the content of free polyphenols accompanied by the increase of the antioxidant potential in relation to the raw grain. The use of the soaking water and pressure during cooking preserved a higher content of polyphenols than the treatments in which the water was discarded and the treatments cooked in an open pan. The evaluation of the bioaccessibility allowed to verify that the digestive process has influence in the concentration of the polyphenols, and that the duodenal stage, in particular, was marked by reduction in the concentration of the phenolic compounds analyzed. The samples in which the soaking water was used in the cooking process had higher content of free polyphenols, however, this content was not totally bioaccessible. Therefore, the discard of the soaking water and the use of cooking pressure are the most suitable procedures for the preservation of the phenolic compounds of the bioaccessible fraction. In this study it was evidenced that the thermal treatment, the matrix and the in vitro digestive process have influence on the phenolic compounds of the bioaccessible fraction.
337

Germina??o e armazenamento de sementes de Stylosanthes Sw. em diferentes ambientes

Am?rico, Fabiana Karla de Ara?jo 27 February 2015 (has links)
Submitted by Verena Bastos (verena@uefs.br) on 2015-08-04T14:26:19Z No. of bitstreams: 1 disserta??o Fabiana K. A. Am?rico.pdf: 1331974 bytes, checksum: 56c0ac8b81ccdb98f55ecb07f21ebfc1 (MD5) / Made available in DSpace on 2015-08-04T14:26:19Z (GMT). No. of bitstreams: 1 disserta??o Fabiana K. A. Am?rico.pdf: 1331974 bytes, checksum: 56c0ac8b81ccdb98f55ecb07f21ebfc1 (MD5) Previous issue date: 2015-02-27 / The forage species of Stylosanthes and its adaptation to different environments have increased demand on the seed trade, which requires accurate information for your use. For the study of seeds conservation is necessary prior knowledge of physiological characteristics and their environmental requirements. The goal this work were establish appropriate conditions of temperature and substrate in germination tests and evaluate the germination of seeds of S. capitata, S. scabra and S. viscosa subjected to different times and storage environments to conservation. The tests were performed in the laboratory of Germination at Universidade Estadual de Feira de Santana-UEFS, Feira de Santana-BA. The temperature tested were: 25, 30 and 20-30 ?C and the substrates were on paper (P), roll paper (RP) and commercial Biomix. To evaluate the behavior in conservation, Stylosanthes seeds were stored for 12 months at room temperature (lab), refrigerator, in freezer and in liquid nitrogen. The species S. capitata, S. scabra and S. viscosa showed variability regarding germination. The seeds germination of S. capitata was improved at on paper and temperatures 30 ?C constant and 20-30 ?C alternating. For S. scabra and S. viscosa seeds were recommended the roll paper at room temperature (25 ?C). Seeds of Stylosanthes respond differently to the conditions of storage and germination tests. S. capitata seeds seem to be more tolerant of the storage conditions, remaining vigorous for 12 months. Besides the physical dormancy, seeds of the S. scabra e S. viscosa it seems put forward the physiological dormancy and the maintenance of seeds in controlled laboratory conditions increased the ability of germination, but with reduced vigor. / O potencial forrageiro das esp?cies de Stylosanthes e sua adapta??o a diferentes ambientes t?m aumentado a demanda no com?rcio de sementes, o que exige informa??es precisas para seu uso. Para o estudo de conserva??o em esp?cies de leguminosas forrageiras do Semi?rido brasileiro, ? necess?rio o conhecimento pr?vio de suas caracter?sticas fisiol?gicas e suas exig?ncias ambientais. Considerando a import?ncia forrageira das esp?cies para o semi?rido nordestino, objetivou-se com esse trabalho estabelecer as condi??es adequadas de temperatura e substrato em testes de germinabilidade e avaliar a germina??o de sementes de S. capitata, S. scabra e S. viscosa submetidas a diferentes tempos e ambientes de armazenamento visando ? conserva??o. Os ensaios foram realizados no Laborat?rio de Germina??o da Unidade Experimental do Horto Florestal da Universidade Estadual de Feira de Santana ? UEFS, Feira de Santana-BA. Para testar a influ?ncia de diferentes temperaturas e substratos, as sementes de Stylosanthes foram submetidas a testes em c?mara de germina??o regulada a temperaturas de 25, 30 e 20-30 ?C e aos substratos sobre papel (SP), rolo de papel (RP) e substrato comercial Biomix. Para avaliar o comportamento na conserva??o, as sementes de Stylosanthes foram armazenadas por 12 meses em temperatura ambiente (laborat?rio), geladeira, em freezer e em nitrog?nio l?quido. As esp?cies S. capitata, S. scabra e S. viscosa apresentaram variabilidade quanto a germinabilidade. Para a germina??o em sementes de S. capitata o mais indicado ? o uso do substrato SP nas temperaturas de 30 ?C constante e 20-30 ?C alternada. Para S. scabra e S. viscosa recomenda-se a utiliza??o do substrato RP na temperatura de 25 ?C constante. Sementes de Stylosanthes respondem diferentemente ?s condi??es de armazenamento e aos testes de germinabilidade. As sementes de S. capitata parecem ser mais tolerantes as condi??es de armazenamento, mantendo-se vigorosas por um per?odo de 12 meses. Sementes de S. scabra e S. viscosa, al?m da dorm?ncia tegumentar demonstram ter uma dorm?ncia fisiol?gica e a manuten??o das sementes em condi??es n?o controladas de laborat?rio aumentam a capacidade de germina??o, por?m com tend?ncia de redu??o do vigor.
338

Symbiosis with Nitrogen-fixing Rhizobia Influences Plant Defense Strategy and Plant-predator Interactions

Godschalx, Adrienne Louise 29 June 2017 (has links)
As sessile organisms, plants evolved a plethora of defenses against their attackers. Given the role of plants as a primary food source for many organisms, plant defense has important implications for community ecology. Surprisingly, despite the potential to alter entire food webs and communities, the factors determining plant investment in defense are not well-understood, and are even less understood considering the numerous symbiotic interactions in the same plant. Legume-rhizobia symbioses engineer ecosystems by fixing nitrogen from the atmosphere in trade for plant photosynthates, yet connecting symbiotic resource exchange to food web interactions has yet to be established. Here I test how rhizobia influence plant defense and tritrophic interactions in lima bean (Fabaceae - Phaseolus lunatus L.): a model plant in chemical ecology research characterized by a broad range of different defenses. Examining suites of traits among lima bean genotypes, highly cyanogenic cultivars and wild type plants (high cyanotypes) produce more hook-shaped trichomes, as a putative combined approach of chemical and mechanical defenses, forming defense syndromes to protect against multiple feeding guilds (Chapter 2). Testing costs that may have contributed to forming tradeoffs among strategies, high cyanotypes show reduced fitness under plant-plant competition relative to low cyanotypes, but when challenged with herbivory, high cyanotypes fitness reductions are no longer evident (Chapter 3). Young leaves, not reproductive organs, are the most cyanogenic lima bean organ, and removal quantitatively decreases fitness, supporting assumptions that the most valuable tissues will be most highly defended (Chapter 4). Testing the degree to which nitrogen-fixing rhizobia contribute to cyanogenesis, high cyanotypes form more nodules than low cyanotypes. Quantitative relationships between nodule number and plant traits highlight the role symbiotic investment plays a role in plant defense and nutritive phenotype, while simultaneously, genotypically-determined levels of defense shape plant investment in symbiosis (Chapter 5). Interestingly, traits that trade off by cyanotype (i.e. high cyanogenesis but low indirect defense) reflect the patterns in plants with nitrogen-fixing rhizobia. Rhizobia-inoculated lima beans show reduced indirect defenses, recruiting fewer parasitoid wasps (Chapter 6) and predatory ants (Chapter 7). Examining plant-ant attraction in greater detail, ants prefer headspace regions above EFN droplets, corresponding with species-specific differences in suites of volatiles, indicating EFN, like floral nectar, can be scented to manipulate insect behavior (Chapter 8). Overall, understanding when investing in traits to recruit predators is more effective than investing in defensive chemistry, and how particular ecological contexts, such as symbioses can influence the outcome of defense allocation strategies remains a fascinating area of research. Determining the mechanisms underlying why rhizobia and other belowground microbial symbionts influence their host plants' above ground interactions, whether plants traits affected by symbiotic microbes are simply a function of the costs and benefits from resource exchange, or whether symbionts can influence the success of primarily direct versus indirectly defended plants is an important question for understanding complex trophic systems and connecting to agricultural implications for more effective biological pest control.
339

The isolation and characterisation of starches from legume grains and their application in food formulations

Lee, Horng Jye, s3048063@student.rmit.edu.au January 2008 (has links)
As a major group of agricultural commodities, legume grains are widely grown and consumed globally, but are often utilised in the whole form. With increasing evidence of nutritional benefits, these grains are potentially sources of novel ingredients including starches. Accordingly the objective of this study has been to investigate legume starches, particularly their isolation, characterisation and incorporation into selected food products. Using chickpea, faba bean, lentil and mung bean, extraction procedures for the practical isolation of legume starches have been evaluated. A relatively simple method has been established, involving grain cracking, steeping in a mildly alkaline solution, followed by washing, double blending, double sieving and sedimentation. The starches collected for the four legumes were oven dried and the recoveries ranged between 29 and 38%. Compositional analyses confirming that the isolation procedure gave relatively pure starches and scanning electron microscopy showed that the granules were typically ellipsoidal. Laser particle size analysis showed mono-modal distributions with mean diameters between 19.6 and 23.9µm. X-ray diffractograms of legume starches were of the typical C-type, with variations in the intensities and peak distribution indicating some differences in the crystallinity of the starches. Suitable conditions for the measurement of starch gelatinisation characteristics by differential scanning calorimetry were investigated. When optimised conditions were applied, the temperature of gelatinisation ranged from 58.9 for lentil to 65.7 °C for mung bean with corresponding enthalpy values of 9.2 and 5.7 Jg-1. Hot-stage optical microscopy confirmed gelatinisation patterns. The starch pastes demonstrated opalescence with some variation in the degree of clarity. The pasting and viscosity properties measured by the Rapid Visco-Analyser showed some variation in pasting temperatures and considerable differences in peak readings with faba bean starch having lowest and mung bean the highest with values of 307 and 676 RVA units, respectively. In order to study the incorporation of the legume starches, two Asian food products having starch as an ingredient, were selected and adapted as model foods. In this context, vermicelli represented a savoury product and coconut cake a sweet product. Vermicelli and coconut cake samples that incorporated chickpea starch were both preferred by most of the panellists over those containing the other legume starches. The overall conclusions are that the starch extraction method adapted in this investigation was a practical approach, producing relatively pure, white starches. The characteristics of the four legume starches showed many similarities, but there were some variations in the properties, indicating that there may be different applications for their incorporation into food formulations. Sensory evaluations confirmed the usefulness of the starches as food ingredients that provide attractive mouthfeel and textural characteristics. Therefore legume starches offer potential as novel food ingredients warranting further evaluation and larger scale feasibility studies.
340

Synchronization of nitrogen availability and plant nitrogen demand : nitrogen and non-nitrogen effects of lentil to subsequent wheat crops

Mooleki, Siyambango Patrick 01 January 2000 (has links)
A study was conducted to determine (1) the N contribution of lentil (<i>Lens culinaris</i> Medikus) and its effect on subsequent wheat (<i>Triticum aestivum</i> L.) crops in the Dark Brown and Brown soil zones of Saskatchewan, (2) if synchronization of available N contributes to the rotation benefit, and (3) N fertilizer replacement value of the N effect of lentil on the subsequent wheat crop. Two approaches were used: a landscape-scale study established at Dinsmore in 1994, and a repeated small-plot study established at several locations (Dinsmore, 1993 and 1994; Clavet, Conquest, Eston and Zealandia, 1995). In the landscape-scale study, N2 fixation by lentil ranged from 28 to 46 kg ha-1, with an average of 34 kg ha -1 N and an N balance of -36 kg ha-1. In the small-plot study, N2 fixation ranged from 10 to 112 kg ha -1 with an average of 59 kg ha-1 N and an N balance of -22 kg ha-1. In the landscape-scale study, preseeding available N on the rotation that incorporated lentil was 29 and 61% higher than in the monocropped wheat in the first and second subsequent crops, respectively. The corresponding values for the small-plot study were 59 and 14%, respectively. N availability was well synchronized with the period of maximum N demand by the wheat crop in both rotations. However, both lentil-residue N and wheat-residue N were poorly synchronized with the period of maximum N demand by the wheat. The rotation effect was exhibited in higher grain yield (23% higher in the landscape-scale study, and 21% higher in the small-plot study). Approximately 10 and 70% of the rotation benefit in the landscape-scale and small plot studies, respectively, were attributed to the N effect. Nitrogen fertilizer replacement value ranged from 47 to 89 kg ha-1 N. Therefore, lentil can fix enough N and indirectly contribute to greater available N in subsequent crops than in crops following non-legumes. However, the actual amount of N derived from lentil residue is small. The greater available N is attributed to spared N and enhanced soil N mineralization. Hence, under the conditions of this study, enhancement of available N contributed more to the rotation benefit than synchronization. The high NFRV show that inclusion of lentil in the rotation can enhance available N in the cropping system and potentially reduce fertilizer N application.

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