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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Efeito radiomodificador do resveratrol em cultura de células de rabdomiossarcoma humano (RD) aplicando o teste do cometa / Radiomodifying effect of resveratrol in human rhabdomyosarcoma (RD) cell culture applying the comet assay

Magalhães, Vanessa Danielle 13 September 2012 (has links)
O câncer é uma doença de alta incidência e é considerado um problema de saúde pública no mundo todo. O resveratrol é um polifenol de defesa que tem a habilidade de inibir a carcinogênese em múltiplos estágios. Este polifenol é sintetizado por uma grande variedade de plantas em resposta a exposição à radiação ultravioleta (UV) ou também, pelo estresse mecânico produzido pela ação de patógenos, agentes químicos e físicos. As videiras são consideradas as plantas que têm uma capacidade elevada de produzir o resveratrol, portanto suco de uva e vinho, principalmente o vinho tinto são considerados uma boa fonte de resveratrol. Os efeitos protetores exercidos pelo resveratrol promovem efeitos como indução da resposta antiinflamatória, atividade antitumoral, prevenção ou inibição de doenças degenerativas, diminuição da incidência de doenças cardiovasculares, inibição da agregação plaquetária, entre outros. Assim, o resveratrol é considerado um protetor celular. Porém, em concentrações mais elevadas, o resveratrol promove o efeito contrário, sensibilizando as células a algum tipo de efeito, como por exemplo, o efeito da radiação ionizante. O objetivo desse trabalho foi estudar o efeito radiomodificador do resveratrol em cultura de células RD (rabdomiossarcoma humano) aplicando o teste do cometa para avaliação do dano e capacidade de reparo celular. Foi obtida a DL50 das células RD em 403 Gy e o índice de citotoxicidade do resveratrol (IC50%) nas células RD foi de 150 μM. A partir destes resultados foram definidas as doses de radiação gama (50 Gy e 100 Gy) e as concentrações de resveratrol (15 μM 30 μM 60 μM) que foram analisadas no trabalho. Foram evidenciados os efeitos do resveratrol como protetor celular na concentração de 15 μM e seu efeito citotóxico em 60 μM. Com a interação da radiação gama, a concentração de 60 μM não mostrou efeito radiossensibilizador estatisticamente significante. / Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a defense polyphenol that possesses a pharmacological activity of carcinogenisis inhibition in multiple levels. This polyphenol is synthesized naturally by a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. In vines this substance is found in elevated concentration. Thus, resveratrol is present in grape juice and wines, especially red wine. The protective effects performed by resveratrol during the process of cell damage, produced by oxidative effects of free radicals, promote anti-inflammatory, anti-platelet and anti- carcinogenic activity, prevent or inhibit degenerative diseases, decrease incidence of cardiovascular diseases. Moreover, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was study the radiomodifying effect of resveratrol in human rhabdomyosarcoma (RD) cell culture applying the comet to assess the cellular damage and repair capacity. The RD cells gamma radiation LD50 was 403 Gy and the resveratrol index cytotoxicity (IC50%) was 150 μM. From these results were defined the gamma radiation doses (50 Gy 100 Gy) and the resveratrol concentrations (15 μM 30 μM 60 μM) were used in this study. The 15 μM and 30 μM concentrations showed cell protective and radioprotective effects. The third and higher concentration used in this work shown to be cytotoxic to RD tumor cells; with gamma radiation presence the 60 μM concentration showed no statistically significant radiosensitizing effects.
12

Associação entre atividade antioxidante in vitro e características químicas, sensoriais, cromáticas e comerciais de vinhos tintos Sul-Americanos / Association between in vitro antioxidant activity and chemical, sensory, chromatic and commercial characteristics of South-American red wines

Granato, Daniel 18 August 2011 (has links)
O vinho tinto é rico em compostos fenólicos com atividade antioxidante, capazes de inativar espécies reativas de oxigênio, minimizando danos celulares oriundos do estresse oxidativo, proporcionando uma redução de risco para doenças crônicas não transmissíveis. Assim, os objetivos desta pesquisa foram identificar associações entre a atividade antioxidante in vitro e fatores relacionados ao tipo de uva, região de produção, perfil sensorial, safra, valor comercial e concentração de compostos fenólicos de vinhos tintos produzidos no Brasil, Chile e Argentina. Inicialmente, os vinhos brasileiros (n=29) foram avaliados em relação à atividade antioxidante (ORAC e DPPH), cor instrumental e compostos fenólicos majoritários, no intuito de verificar qual classe de fenólicos estaria associada com a atividade antioxidante. Verificou-se que tanto os compostos fenólicos totais como os flavonóides totais, com destaque aos flavonóides não-antociânicos, se associaram significativamente (p<0,05) com a atividade antioxidante. Em um segundo passo, as características sensoriais, a cor, o valor comercial e a atividade antioxidante das 80 amostras de vinhos Sul-Americanos, distribuídas em Merlot (n=9), Pinot Noir (n=17), Malbec (n=11), Syrah (n=12), Cabernet Sauvignon (n=24), e vinhos de uvas americanas (Vitis labrusca) (n=7) foram avaliados usando estatística multivariada, objetivando-se verificar se a qualidade sensorial das amostras estaria associada com o valor comercial, cor, e à atividade antioxidante. De uma forma geral, os vinhos chilenos e argentinos apresentaram maior atividade antioxidante, valor comercial, intensidade de odor, qualidade sensorial, índice de acidez e taninos, ao passo que os vinhos brasileiros obtiveram os menores valores para os atributos sensoriais. Os vinhos de uvas americanas apresentaram menores valores para todas as variáveis. As varietais Syrah, Malbec e Cabernet Sauvignon apresentaram maior capacidade antioxidante e melhores características sensoriais, sendo que esse resultado foi independente da safra e de procedência. Como última etapa, as amostras de vinhos produzidas com uva V. vinifera (n=73) foram classificadas, usando análise hierárquica de agrupamentos, de acordo com o valor comercial, qualidade sensorial e capacidade antioxidante medida por ORAC e DPPH, e os grupos foram caracterizados em relação à sua composição fenólica. Os resultados indicaram que a atividade antioxidante se correlacionou positivamente com o conteúdo de fenólicos totais, flavonóides totais, ácido gálico, quercetina, catequina, ácido ferúlico, miricetina, caempferol, e rutina, sendo que apenas os conteúdos de miricetina, ácido gálico e quercetina foram diferentes (p<0,05) entre os grupos. Nenhum composto fenólico avaliado nesse estudo associou-se com a as diferenças sensoriais dos grupos de vinho. / Red wine is rich in phenolic compounds with antioxidant activity, being able to buffer reactive oxygen species, thus decreasing the risk of non-transmissible chronic diseases. In this regard, the objectives of this research aimed at identifying associations between the in vitro antioxidant activity and factors related to grape varietal, region of production, sensory profile, vintage, color, commercial value, and concentration of phenolic compounds of red wines produced in Brazil, Chile, and Argentina. Initially, the Brazilian red wines (n = 29) were assessed in relation to antioxidant activity, instrumental color, and major phenolic compounds with the objective to verify which phenolic class was associated with the antioxidant activity. Both the total phenolic compounds and total flavonoids, with special attention to non-anthocyanin flavonoids, were significantly associated with the antioxidant activity. In a second step, the sensory characteristics, color, commercial value, and antioxidant activity of the 80 red wine samples, which were distributed in Merlot (n=9), Pinot Noir (n=17), Malbec (n=11), Syrah (n=12), Cabernet Sauvignon (n=24), and table wines (Vitis labrusca) (n=7) were evaluated using multivariate statistical techniques, with the aim to verify how the overall perception of quality of wines was related to commercial value, color and antioxidant activity. In a general way, te Chilean and Argentinean red wines displayed a higher antioxidant activity, commercial value, intensity of odors, sensory perception of quality, acidity level, and tannin level, whereas the Brazilian samples obtained the lowest values for the sensory attributes. The table wines presented the lowest values for all response variables. Syrah, Malbec and Cabernet Sauvignon varietals presented the highest antioxidant activity and most favorable sensory features, and this result was independent of wine\'s vintage and origin. As a last step, the wines produced with V. vinifera grapes (n=73) were classified, using hierarchical cluster analysis, in relation to commercial value, sensory quality and antioxidant activity measured by ORAC and DPPH assays, and the groups were characterised in relation to the phenolic composition.The results showed that the antioxidant capacity correlated to the total contents of phenolic compounds, flavonoids, gallic acid, quercetin, catechin, ferulic acid, myricetin, kaempferol, and rutin, where only the contents of quercetin, gallic acid, and myricetin were different (p < 0.05) whithin clusters. None of the phenolic compounds analysed in this research was associated with sensory differences within clusters.
13

Efeito radiomodificador do resveratrol em cultura de células de rabdomiossarcoma humano (RD) aplicando o teste do cometa / Radiomodifying effect of resveratrol in human rhabdomyosarcoma (RD) cell culture applying the comet assay

Vanessa Danielle Magalhães 13 September 2012 (has links)
O câncer é uma doença de alta incidência e é considerado um problema de saúde pública no mundo todo. O resveratrol é um polifenol de defesa que tem a habilidade de inibir a carcinogênese em múltiplos estágios. Este polifenol é sintetizado por uma grande variedade de plantas em resposta a exposição à radiação ultravioleta (UV) ou também, pelo estresse mecânico produzido pela ação de patógenos, agentes químicos e físicos. As videiras são consideradas as plantas que têm uma capacidade elevada de produzir o resveratrol, portanto suco de uva e vinho, principalmente o vinho tinto são considerados uma boa fonte de resveratrol. Os efeitos protetores exercidos pelo resveratrol promovem efeitos como indução da resposta antiinflamatória, atividade antitumoral, prevenção ou inibição de doenças degenerativas, diminuição da incidência de doenças cardiovasculares, inibição da agregação plaquetária, entre outros. Assim, o resveratrol é considerado um protetor celular. Porém, em concentrações mais elevadas, o resveratrol promove o efeito contrário, sensibilizando as células a algum tipo de efeito, como por exemplo, o efeito da radiação ionizante. O objetivo desse trabalho foi estudar o efeito radiomodificador do resveratrol em cultura de células RD (rabdomiossarcoma humano) aplicando o teste do cometa para avaliação do dano e capacidade de reparo celular. Foi obtida a DL50 das células RD em 403 Gy e o índice de citotoxicidade do resveratrol (IC50%) nas células RD foi de 150 &mu;M. A partir destes resultados foram definidas as doses de radiação gama (50 Gy e 100 Gy) e as concentrações de resveratrol (15 &mu;M 30 &mu;M 60 &mu;M) que foram analisadas no trabalho. Foram evidenciados os efeitos do resveratrol como protetor celular na concentração de 15 &mu;M e seu efeito citotóxico em 60 &mu;M. Com a interação da radiação gama, a concentração de 60 &mu;M não mostrou efeito radiossensibilizador estatisticamente significante. / Cancer is a disease with high incidence and it is considered a worldwide public health problem. Resveratrol is a defense polyphenol that possesses a pharmacological activity of carcinogenisis inhibition in multiple levels. This polyphenol is synthesized naturally by a wide variety of plants according to response of ultraviolet radiation (UV) exposition or according to mechanical stress resulting of pathogens or chemical and physical agents. In vines this substance is found in elevated concentration. Thus, resveratrol is present in grape juice and wines, especially red wine. The protective effects performed by resveratrol during the process of cell damage, produced by oxidative effects of free radicals, promote anti-inflammatory, anti-platelet and anti- carcinogenic activity, prevent or inhibit degenerative diseases, decrease incidence of cardiovascular diseases. Moreover, resveratrol is considered as a cell radioprotector. On the other hand, in some elevated concentrations resveratrol may be considered as a radiosensitizing. The aim of this work was study the radiomodifying effect of resveratrol in human rhabdomyosarcoma (RD) cell culture applying the comet to assess the cellular damage and repair capacity. The RD cells gamma radiation LD50 was 403 Gy and the resveratrol index cytotoxicity (IC50%) was 150 &mu;M. From these results were defined the gamma radiation doses (50 Gy 100 Gy) and the resveratrol concentrations (15 &mu;M 30 &mu;M 60 &mu;M) were used in this study. The 15 &mu;M and 30 &mu;M concentrations showed cell protective and radioprotective effects. The third and higher concentration used in this work shown to be cytotoxic to RD tumor cells; with gamma radiation presence the 60 &mu;M concentration showed no statistically significant radiosensitizing effects.
14

Efeito protetor do vinho ruby cabernet em um modelo de hipercolesterolemia em camundongos / Protective effect of ruby cabernet wine in a model of hypercholesterolemia in mice

Moraes, Etiára de Mattos January 2018 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2018-09-28T14:20:50Z No. of bitstreams: 1 Etiára de Mattos Moraes.pdf: 1135022 bytes, checksum: df104ba47f712207709c121a7e6d2295 (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2018-09-28T14:21:04Z (GMT) No. of bitstreams: 1 Etiára de Mattos Moraes.pdf: 1135022 bytes, checksum: df104ba47f712207709c121a7e6d2295 (MD5) / Made available in DSpace on 2018-09-28T14:21:04Z (GMT). No. of bitstreams: 1 Etiára de Mattos Moraes.pdf: 1135022 bytes, checksum: df104ba47f712207709c121a7e6d2295 (MD5) Previous issue date: 2018 / O colesterol é um componente lipídico importante de todas as membranas celulares e da bainha de mielina, desempenhando um importante papel na integridade sináptica e atividade neural. O colesterol também atua como substrato para a síntese de ácidos biliares no fígado e precursor de hormônios esteroidais. No entanto, tem sido apontada uma ligação entre os níveis plasmáticos elevados de colesterol e o desenvolvimento de lesões ateroscleróticas. A aterosclerose é uma doença inflamatória crônica de origem multifatorial, que acomete a camada íntima de artérias de médio e grande calibres. A formação da placa aterosclerótica inicia-se com a agressão ao endotélio vascular devido a diversos fatores de risco como dislipidemia, hipertensão arterial ou tabagismo. A uva, o vinho e produtos derivados da uva contém grande quantidade de compostos fenólicos que agem como antioxidantes. O consumo desses flavonoides está associado ao risco reduzido de eventos coronários, e a ingestão moderada de vinho tinto inibe a agregação plaquetária. O dano ao receptor de lipoproteína de baixa intensidade aumenta os níveis plasmáticos de LDL-C, resultando em deficiência na depuração do sangue desta lipoproteína. Em vista disso, o objetivo do presente estudo foi investigar os efeitos protetores do vinho tinto Ruby Cabernet (RCR) produzido na cidade de Itaqui-RS contra a dislipidemia, estresse oxidativo e inflamação sistêmica em camundongos hipercolesterolêmicos. Foram utilizados camundongos C57BJ6 do tipo selvagem (90 dias de idade) e com deleção gênica 2 LDLr-/- que foram tratados com o vinho RCR (dose diária de 400 μL por gavagem) durante 90 dias. Após o tratamento com o vinho RCR, os animais foram eutanasiados e o sangue foi coletado para ensaios bioquímicos. Os resultados do presente estudo demonstraram que o vinho RCR tem uma capacidade antioxidante significativa, como revelado por ensaios in vitro. Além disso, o vinho RCR atenuou os seguintes parâmetros bioquímicos alterados nos animais LDLR-/- níveis aumentados de colesterol total, triglicerídeos, lipoproteína de baixa densidade, lipoproteína de baixa densidade oxidada e níveis diminuídos de HDL no sangue. O vinho RCR também aliviou o estresse oxidativo no sangue dos animais LDLr-/-, como revelado pela redução dos níveis de malondialdeído, proteína carbonilada, espécies reativas de oxigênio e aumento dos níveis de glutationa. Os animais LDLr-/- exibiram um aumento acentuado nos níveis do fator nuclear Kappa-B e das citocinas inflamatórias IL-6, IL-1β e TNF-α, e uma redução da citocina anti-inflamatória IL-10. O vinho RCR atenuou essas alterações no plasma sanguíneo. Concluímos que o vinho RCR possui um importante potencial antioxidante in vitro. Além disso, o vinho RCR tem efeitos hipolipemiantes, antioxidantes e anti-inflamatórios em animais LDLr-/-. / Cholesterol is an important lipid component of all cell membranes and the myelin sheath, playing an important role in synaptic integrity and neural activity. Cholesterol also acts as a substrate for the synthesis of bile acids in the liver and precursor of steroidal hormones. However, a link has been identified between elevated plasma cholesterol levels and the development of atherosclerotic lesions. Atherosclerosis is a chronic inflammatory disease of multifactorial origin, which affects the intimate layer of arteries of medium and large calibers. The formation of atherosclerotic plaques begins with aggression to the vascular endothelium due to several risk factors such as dyslipidemia, arterial hypertension or smoking. Grapes, wine and grape products contain large amounts of phenolic compounds that act as antioxidants. Consumption of these flavonoids is associated with reduced risk of coronary events, and moderate red wine intake inhibits platelet aggregation. Low-intensity lipoprotein receptor damage increases plasma LDL-C levels, resulting in deficiency in blood clearance of this lipoprotein. In view of this, the objective of the present study was to investigate the protective effects of Ruby Cabernet red wine (RCR) produced in the city of Itaqui-RS against dyslipidemia, oxidative stress and systemic inflammation in hypercholesterolemic mice. Wild type C57BJ6 mice (90 days old) with a deletion LDLr-/- mice that were treated with RCR wine (daily dose of 400 μL per gavage) for 90 days. After treatment with the RCR wine, the animals were euthanized and blood was collected for biochemical assays. The results of the 4 present study demonstrated that RCR wine has a significant antioxidant capacity as revealed by in vitro assays. In addition, RCR wine attenuated the following altered biochemical parameters in LDLR animals-/- increased levels of total cholesterol, triglycerides, low density lipoprotein, oxidized low density lipoprotein and decreased levels of HDL in the blood. RCR wine also alleviated the oxidative stress in the blood of LDLr-/- animals, as revealed by the reduction of levels of malondialdehyde, carbonylated protein, reactive oxygen species and increased levels of glutathione. The LDLr-/- animals exhibited a marked increase in nuclear Kappa-B factor and inflammatory cytokines IL-6, IL-1β and TNF-α, and a reduction of the anti-inflammatory cytokine IL-10. RCR wine attenuated these changes in blood plasma. We conclude that RCR wine has an important antioxidant potential in vitro. In addition, RCR wine has lipid-lowering, antioxidant and anti-inflammatory effects in LDLr-/- animals.
15

Associação entre atividade antioxidante in vitro e características químicas, sensoriais, cromáticas e comerciais de vinhos tintos Sul-Americanos / Association between in vitro antioxidant activity and chemical, sensory, chromatic and commercial characteristics of South-American red wines

Daniel Granato 18 August 2011 (has links)
O vinho tinto é rico em compostos fenólicos com atividade antioxidante, capazes de inativar espécies reativas de oxigênio, minimizando danos celulares oriundos do estresse oxidativo, proporcionando uma redução de risco para doenças crônicas não transmissíveis. Assim, os objetivos desta pesquisa foram identificar associações entre a atividade antioxidante in vitro e fatores relacionados ao tipo de uva, região de produção, perfil sensorial, safra, valor comercial e concentração de compostos fenólicos de vinhos tintos produzidos no Brasil, Chile e Argentina. Inicialmente, os vinhos brasileiros (n=29) foram avaliados em relação à atividade antioxidante (ORAC e DPPH), cor instrumental e compostos fenólicos majoritários, no intuito de verificar qual classe de fenólicos estaria associada com a atividade antioxidante. Verificou-se que tanto os compostos fenólicos totais como os flavonóides totais, com destaque aos flavonóides não-antociânicos, se associaram significativamente (p<0,05) com a atividade antioxidante. Em um segundo passo, as características sensoriais, a cor, o valor comercial e a atividade antioxidante das 80 amostras de vinhos Sul-Americanos, distribuídas em Merlot (n=9), Pinot Noir (n=17), Malbec (n=11), Syrah (n=12), Cabernet Sauvignon (n=24), e vinhos de uvas americanas (Vitis labrusca) (n=7) foram avaliados usando estatística multivariada, objetivando-se verificar se a qualidade sensorial das amostras estaria associada com o valor comercial, cor, e à atividade antioxidante. De uma forma geral, os vinhos chilenos e argentinos apresentaram maior atividade antioxidante, valor comercial, intensidade de odor, qualidade sensorial, índice de acidez e taninos, ao passo que os vinhos brasileiros obtiveram os menores valores para os atributos sensoriais. Os vinhos de uvas americanas apresentaram menores valores para todas as variáveis. As varietais Syrah, Malbec e Cabernet Sauvignon apresentaram maior capacidade antioxidante e melhores características sensoriais, sendo que esse resultado foi independente da safra e de procedência. Como última etapa, as amostras de vinhos produzidas com uva V. vinifera (n=73) foram classificadas, usando análise hierárquica de agrupamentos, de acordo com o valor comercial, qualidade sensorial e capacidade antioxidante medida por ORAC e DPPH, e os grupos foram caracterizados em relação à sua composição fenólica. Os resultados indicaram que a atividade antioxidante se correlacionou positivamente com o conteúdo de fenólicos totais, flavonóides totais, ácido gálico, quercetina, catequina, ácido ferúlico, miricetina, caempferol, e rutina, sendo que apenas os conteúdos de miricetina, ácido gálico e quercetina foram diferentes (p<0,05) entre os grupos. Nenhum composto fenólico avaliado nesse estudo associou-se com a as diferenças sensoriais dos grupos de vinho. / Red wine is rich in phenolic compounds with antioxidant activity, being able to buffer reactive oxygen species, thus decreasing the risk of non-transmissible chronic diseases. In this regard, the objectives of this research aimed at identifying associations between the in vitro antioxidant activity and factors related to grape varietal, region of production, sensory profile, vintage, color, commercial value, and concentration of phenolic compounds of red wines produced in Brazil, Chile, and Argentina. Initially, the Brazilian red wines (n = 29) were assessed in relation to antioxidant activity, instrumental color, and major phenolic compounds with the objective to verify which phenolic class was associated with the antioxidant activity. Both the total phenolic compounds and total flavonoids, with special attention to non-anthocyanin flavonoids, were significantly associated with the antioxidant activity. In a second step, the sensory characteristics, color, commercial value, and antioxidant activity of the 80 red wine samples, which were distributed in Merlot (n=9), Pinot Noir (n=17), Malbec (n=11), Syrah (n=12), Cabernet Sauvignon (n=24), and table wines (Vitis labrusca) (n=7) were evaluated using multivariate statistical techniques, with the aim to verify how the overall perception of quality of wines was related to commercial value, color and antioxidant activity. In a general way, te Chilean and Argentinean red wines displayed a higher antioxidant activity, commercial value, intensity of odors, sensory perception of quality, acidity level, and tannin level, whereas the Brazilian samples obtained the lowest values for the sensory attributes. The table wines presented the lowest values for all response variables. Syrah, Malbec and Cabernet Sauvignon varietals presented the highest antioxidant activity and most favorable sensory features, and this result was independent of wine\'s vintage and origin. As a last step, the wines produced with V. vinifera grapes (n=73) were classified, using hierarchical cluster analysis, in relation to commercial value, sensory quality and antioxidant activity measured by ORAC and DPPH assays, and the groups were characterised in relation to the phenolic composition.The results showed that the antioxidant capacity correlated to the total contents of phenolic compounds, flavonoids, gallic acid, quercetin, catechin, ferulic acid, myricetin, kaempferol, and rutin, where only the contents of quercetin, gallic acid, and myricetin were different (p < 0.05) whithin clusters. None of the phenolic compounds analysed in this research was associated with sensory differences within clusters.
16

The effects of dissolved oxygen and enological treatments on quality parameters in wine and cider

Ragnemalm, Johan January 2014 (has links)
Dissolved oxygen has previously been shown to affect the colour and sensory properties of red and white wine during storage. A number of different wines and wine based sparkling ciders are made at Kiviks Musteri AB. The aim of this work is to study the effects of dissolved oxygen and different enological treatments on sensory quality and colour of red wine and sparkling apple cider during storage at different temperatures. The effects of fermentation and fining on foaming ability of pear wine are also studied.   Samples of red wine were taken after different processing steps such as pumping, sulphuration, pasteurization and filling. To evaluate the effects of the processes on the wine, dissolved oxygen, colour and free SO2 were measured in each. Measurements were also made on samples of red wine stored at either 38°C or room temperature for different amounts of time. Sensory evaluations were also made of the wine samples. Colour was measured by measuring absorbance at 420, 520 and 620 nm. Dissolved oxygen was also measured after different processing steps during production of apple cider. To study the effects of dissolved oxygen on cider, three different batches of apple cider were produced, with different concentrations of dissolved oxygen. The samples were stored at either 38°C or room temperature for one week. Measurements of absorbance at 420 nm and free SO2, along with sensory evaluation were made on the cider samples before and after storage. Fermentation and fining of pear wine were made in small scale and the foaming ability was compared to that of large scale factory produced wine.   Pumping and filling had negative impact on the flavour of red wine. Colour intensity increased while free SO2 decreased during storage of red wine. The sensory quality decreased during storage and a higher storage temperature had a distinctive impact on this decrease. Dissolved oxygen had no noticeable effect on changes in sensory properties of neither red wine nor cider during storage. A higher concentration of dissolved oxygen was correlated to a higher increase in colour intensity of red wine though. A higher decrease was also seen in free SO2 in red wine samples with higher dissolved oxygen content when stored at 38°C. Fermentation had a large impact on foaming properties of pear wine. Small scale wine fermentation resulted in much lower foaming ability than large scale fermentation. / Syrehalten i viner har i tidigare studier visat sig kunna påverka både färg- och smakförändringar i vinerna under längre tids lagring. På Kiviks Musteri AB i Skåne produceras en mängd olika sorters vin och vinbaserade cidrar. Målet med den här studien är att studera vilken effekt syrehalten har på smak och färg i viner och cidrar från Kiviks Musteri som får lagras i olika temperaturer. Effekten av olika processteg under produktionen studeras också. Slutligen studeras även hur skumbildningen i päronvin påverkas av jäsning och klarning av vinet.   Prover av rödvin togs efter de olika processtegen vinet genomgår på Kiviks Musteri. Proverna lagrades olika länge i antingen 38°C eller rumstemperatur. Färgstyrka och smak analyserades på proverna före och efter lagringen. Syrehalten analyserades också i proverna direkt efter att de tagits och svavelhalten i proverna analyserades före och efter lagringen för att mäta hur mycket proverna oxiderades under lagringen. Mätningar av syrehalt gjordes även efter olika processteg under produktionen av äppelcider på Kiviks Musteri. Vilken effekt syrehalten har på äppelcider studerades genom att tre olika satser äppelcider med olika syrehalt tillverkades. Prover från dessa lagrades en vecka i antingen 38°C eller rumstemperatur. Därefter analyserades färgstyrka, svavelhalt och smak på proverna. Hur skumbildning i päronvin påverkas av jäsning och klarning studerades genom att päronvin fick jäsa och klarnas antingen i stor skala i musteriets tankar eller i liten skala på ett laboratorium. Skumbildningen mättes genom ett test där vinprover blandades med kolsyrat vatten.   De processer som inverkade starkast på smaken på rödvin var pumpning och tappning, vilka gav tydliga smakförsämringar. När rödvin lagrades så minskade svavelhalten medan färgstyrkan ökade. En försämring av smaken skedde också under lagringen, särskilt när vinet lagrades i 38°C. Syrehalten hade ingen tydlig påverkan på smaken av vare sig rödvin eller äppelcider. Syrehalten i rödvin hade däremot ett svagt samband med ökningen i förgstyrka i rödvin. Syrehalten hade även ett samband med minskningen av svavelhalten i de prover av rödvin som lagrades i 38°C. Skumbildningen i päronvin påverkades väldigt starkt av jäsningen, medan klarningen hade begränsad effekt. Skumbildningen var vesäntligt mycket lägre i päronvin som jäst i liten skala på laboratoriet än i det vin som jäst i musteriets tankar.
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Investigation of the chemical and sensory properties of red wine pigments.

Oberholster, Anita January 2008 (has links)
Phenolic compounds play an important role in red wine colour, bitterness, astringency, as well as a range of other tactile or 'mouth-feel' characteristics. Progressive changes of phenolic compounds, initially extracted from grapes, occur during the storage and aging of red wines. The decrease of astringency occurring during wine aging has been considered as a result of mainly anthocyanin-flavanol condensation either directly or mediated by aldehydes. The contribution of these polymeric pigments formed during wine aging to the unique properties of red wine is an important question still unanswered. Experiments were conducted to synthesise polymeric pigments in model wine solutions under different conditions in the absence of acetaldehyde to provide material for chemical and sensory studies. Only small amounts of polymeric pigments were formed in these experiments confirming that direct polymerisation is a slow process. The low yield of polymers made it necessary to investigate the isolation of polymeric pigments directly from wine. A preparative fractionation protocol was developed to obtain fractions enriched in different red wine pigment combinations for further investigation. A HPLC method was also developed that separated the pigmented and non-pigmented polymers, as well as the monomeric anthocyanins, flavanols (monomeric to trimeric), flavonols and hydroxycinnamic acids from each other. A 6 month old and a 5 year old Shiraz wine were fractionated and further analysed by acid hydrolysis in the presence of a nucleophile, gel permeation chromatography (GPC) and by different mass spectrometry techniques. The various fractions isolated from the 6 month old wine contained combinations of pentameric to dimeric pigments, while those from the 5 year old wine contained pigments with an average degree of polymerisation (DP) of at least 11 but possibly up to 32. Experiments were conducted to determine the sensorial contribution of anthocyanins to wine as well as the effect of anthocyanin-flavanol polymerisation reactions taking place during maturation. It was shown that significant changes occur in the polymeric phenol composition and in the mean degree of polymerisation of Shiraz wine during aging. With aging more skin tannin were incorporated in the pigmented polymers and the percentage of galloylation in these polymers decreased. In order to describe the sensory attributes of the polymeric pigments a refined vocabulary, describing the astringent and other mouth-feel sensations elicited by dry red table wines representing different styles was developed and called the mouth-feel wheel. The developed mouth-feel wheel was used in a study to investigate the contribution of anthocyanins and anthocyanin-proanthocyanidin reaction products to the mouth-feel properties of red wine. Wines were made from both red and white grapes with and without pomace contact, as well as with and without anthocyanin addition to the white grapes. The white wine made like a red wine did not exhibit the same mouth-feel sensory attributes of a red wine: it was lower in viscosity, less particulate in nature and lower in intensity for the astringency descriptors fine emery, dry and grippy. The presence of anthocyanins during fermentation appeared to increase the intensity of astringency related terms. Treatments with added anthocyanins increased the amount of polymeric phenols to twice that when compared to treatments without added anthocyanins. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1345103 / Thesis (Ph.D.) - University of Adelaide, School of Agriculture, Food and Wine, 2008
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Consequences of extended maceration for red wine colour and phenolics.

Joscelyne, Venetia Louise January 2009 (has links)
The consequences of pre-fermentation and post-fermentation extended maceration (EM) on colour, mouthfeel and phenolic composition were investigated in Pinot noir (2004), Grenache (2006) and Shiraz (2007) (Vitis vinifera L.) wines. Experimental wines were made using cold soak, post-fermentation EM, and standard fermentation treatments (C). Cold soak treatments included a 3-day cold soak at 10°C (CS), with an additional comparison of plunging effects for the 2004 wines (CSP). Post-fermentation extended maceration treatments were 1- or 3-weeks on skins in 2004 (PS1 and PS3 respectively), and 3-weeks in 2006 and 2007 (PS3). A variety of chemical and sensory test methods were used to determine changes in phenolic components and organoleptic properties between treatments of all 3 varietals as they aged in the bottle. Among other results, it was determined if wines made with a period of cold soak had increased colour intensity, and increased concentrations of monomeric anthocyanins and pigmented polymers compared to control wines. It was also determined if wines made with a period of post-fermentation EM had increased concentrations of the flavan-3-ols (+)-catechin and (−)-epicatechin, and tannin, decreased colour intensity and modified mouthfeel compared to the other wine treatments. A greater understanding of Australian red winemakers’ opinions on EM regimes and their use in Australian wineries was obtained by survey. Survey results confirmed that EM is used extensively in Australian wineries but that winemakers have poor understanding of the consequences of EM regimes for red wine properties. The survey confirmed that winemakers are concerned about the economic cost and logistic pressures associated with the use of EM regimes during vintage. Wines made using EM need to spend longer in fermentation vessels, which are in high demand during this time. Findings from this study provide winemakers with more information to consider before making decisions about their use of EM regimes. Survey findings showed more winemakers would use EM regimes if logistic and economic pressures did not apply. However, results suggest that even if winemakers did adopt EM practices, some may not achieve what they believe to be the outcome of these regimes, such as improved colour or mouthfeel properties. For instance, results showed that cold soaking did not make a difference to wine colour compared to conventional fermentation maceration. Even without cold soaking red must, winemakers may be able to achieve the same or very similar wine organoleptic characteristics at a reduced cost. Similarly, no significant effects of plunging during cold soak were observed. Post-fermentation EM visibly reduced wine colour intensity and imparted a browner hue to the wine compared to red wine that was pressed off skins upon reaching dryness. This EM regime is therefore unlikely to benefit winemakers who are seeking to produce highly coloured wines. However, prolonged maceration post-fermentation did increase the intensity of perceived bitterness and increased the concentration of wine flavan-3-ols and tannins. Winemakers may therefore influence the desired balance between the extraction of these wine phenolics (and the associated outcome for taste and mouthfeel properties) and economic considerations by varying the duration of maceration post-fermentation. / http://proxy.library.adelaide.edu.au/login?url= http://library.adelaide.edu.au/cgi-bin/Pwebrecon.cgi?BBID=1362928 / Thesis (Ph.D.) - University of Adelaide, School of Agriculture, Food and Wine, 2009.
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Health aspects of wine antioxidants: Composition and in vitro bioavailability

Irine Ginjom Unknown Date (has links)
The antioxidant capacity of phenolic compounds in red wine is suggested to be responsible for their health-promoting effects. Compared to other wines, little information is available on phenolic compositions and antioxidant capacity of Australian wine. Information related to the fate of these phenolics in the body once consumed is also very limited. The overall aim of this research was to investigate the relevance of red wine consumption as a source of health-giving antioxidants in humans. The phenolic composition of wine was determined using the Folin-Ciocalteu (total phenolic), aluminium chloride (total flavonols), methyl cellulose precipitation (MCP) (total tannins), pH differential (total monomeric anthocyanins), bisulfite bleaching (total polymeric anthocyanin fractions), and liquid chromatographic (LC-MS) (individual phenolics) methods. Antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2’-azino-bis-93-ethylbenzthiazoline-6-sulfonic acid (ABTS) and oxygen radical absorbance capacity (ORAC) assays. The phenolic and antioxidant data were then used to establish the relationship between these two parameters in wines from different varieties (Shiraz, Cabernet Sauvignon and Merlot) and winemaking stages (crushing, fermentations, oaking and bottling). By using an in vitro digestion model that mimics the upper gastrointestinal tract (GIT) digestion, the stability of the wine phenolics during digestion was examined. Finally, to gain a better understanding of the post-digestion absorption of wine phenolics, their permeability across Caco-2 cell monolayers was evaluated. A total of 8 monomeric anthocyanins and 17 other phenolic compounds were positively identified in the red wines using LC-MS analysis. Most of the phenolic categories showed some positive correlations with the antioxidant activities but none of the individual phenolic compounds showed a strong correlation with the total antioxidant activity of the wine, implying a combined contribution of many wine phenolics to antioxidant effects. The phenolic compositions and antioxidant activities of three of Australia’s most common red wines varieties - Shiraz, Cabernet Sauvignon and Merlot were not different from each other, possibly due to the variability within each grape cultivar. During the winemaking process, the total phenolic content and the associated antioxidant activity of the wine increased during the fermentation process, as more phenolics are being extracted from grape skin, seeds and stems into the wine. During oak and bottle ageing, the total phenolic contents were stabilised. Most of the wine phenolics were more stable under acidic conditions (pH 2 and 5.5) than neutral or alkaline conditions (pH 7.4 and 9). This may partly explain the stability of the wine phenolics subjected to the acidic (pH 2) gastric digestion and their loss following simulated pancreatic digestion (pH 7.4). In addition, sample pre-treatment procedures prior to LC-MS analysis may have removed some antioxidants in the form of degradation products and/or new polymeric compounds following the in vitro gastric and pancreatic digestion processes. The missing products appeared to be detected by both the Folin-Ciocalteu method and ORAC assay, which measured the phenolic compounds and their antioxidant activity, after the pancreatic digestion. This suggests that the instability of phenolic compounds at pH 7.4, results in the transformation of most of the oral phenolic antioxidants into more stable forms in the GIT, which in turn contribute positively to the overall antioxidant activities of the ingested wine. All of the original wine phenolics had very low permeabilities across Caco-2 cell monolayers, except for syringic acid, p-coumaric acid and an unknown phenolic acid. Limited surface area for absorption (0.33 cm2) and the limited peak detection sensitivity in the LC method may have contributed towards the difficulty in detecting and identifying compounds with low permeability. In addition, extensive metabolism of absorbed phenolics by the Caco-2 cells may occur based on the appearance of several new peaks. However, due to their low concentrations and lack of reference, the identities of the new products and metabolites remain unknown. The present in vitro study suggests that upon ingestion, most of the original phenolic compounds in red wine are lost either through degradation to new compounds and/or complexation with other compounds. However, these products seem to possess some antioxidant activity and may be the key compounds responsible for the health-promoting effects of red wine. The limitation of the present study in detecting and fully identifying these breakdown products and metabolites should be addressed in future studies.
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Avaliação pré-clínica dos efeitos cardiovasculares induzidos pelo liofilizado do vinho tinto do Vale do Rio São Francisco em ratos abordagem in vivo e in vitro

Oliveira, Aurylene Carlos de 03 November 2011 (has links)
Made available in DSpace on 2015-05-14T12:59:30Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3470014 bytes, checksum: ec4369a3d6de32a48a92ee347d505698 (MD5) Previous issue date: 2011-11-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Several epidemiological studies indicated that regular intake of red wine is associated with a decrease global mortality. The protective effect has been attributable, at least in part, to polyphenols. The cardiovascular effects induced by lyophilized red wine from Vale do São Francisco (LVTVSF) were evaluated in this study using in vivo and in vitro assays. The lyophilized red wine from Vale do São Francisco (LVTVSF) contains a series of flavonols, such, quercetin, myricetin and kaempferol. The red wine lyophilized was able to reduce mean arterial pressure (MAP) in L-NAME hypertensive rats compared to controls (143.7 ± 4.7 versus 172.5 ± 4.7 mmHg). In normotensive rats the administration of LVTVSF (10, 30, 90 mg/kg i.v.) randomly, induced hypotension (-24.0 ± 1.2; -32.4 ± 1.3; -51.4 ± 1.5%) and tachycardic effects (14.5 ± 2.3; 19.5 ± 1.7; 28.4 ± 2.1%). The pre-treatment with L-NAME (20 mg / kg i.v.), inhibitor of endothelial nitric oxide synthase, attenuated the hypotensive effect induced by LVTVSF. In isolated normotensive rat mesenteric artery rings LVTVSF elicited concentration-dependent relaxation of PHE-induced contraction (MR = 87.22 ± 3.59%). After removal of the vascular endothelial the vasorelaxant effect was significantly attenuated (MR = 32.07 ± 2.07%, p < 0.05), suggesting the involvement of endothelium-derived relaxing factor. After incubation with L-NAME (100 μM) and ODQ (10 mM), inhibitor of soluble guanylyl cyclase, the relaxation response was significantly attenuated (MR= 22.64 ± 3.74%, p < 0.05; MR = 37.08 ± 4.60%, p < 0.05, respectively). Similar results was also obtained rings incubed with KCl (20 mM), a modulator of potassium efflux; TEA (1 mM), nonselective blocker for potassium channels; (MR = 46.04 ± 9.87%, p < 0,05; MR = 44.40 ± 5.80%, p < 0,05; respectively). The LVTVSF was able to increase the NO levels in endothelial cells of the rabbit aorta. In the presence of charybdotoxin and apamin the relaxant response was not attenuated. Incubation with inhibitors of reactive oxygen species, N-acetylcysteine (NAC) (10 mM), tempol (100 μM) and apocynin (10 μM), reduces the vasorelaxation. After pre-treatment with atropine and indometacin, the vasorelaxant effect induced by LVTVSF was no attenuated. In endothelial cells of the rabbit aorta LVTVSF was able to increase production of ROS. These results together suggest that the hypotensive effect induced by LVTVSF in normotensive rats is probably due to a decrease in total peripheral resistance as a result of activation of the eNOS-NO-cGMP, involving the redox sensitive mechanism. These effects may be due to flavonoids found in LVTVSF. / Estudos epidemiológicos demonstram que o consumo regular de vinho está associado a um decréscimo da mortalidade global. Acredita-se que o efeito protetor seja decorrente, pelo menos em parte, da presença de polifenóis. A atividade biológica do Liofilizado do vinho tinto do Vale do São Francisco (LVTVSF) foi estudada no sistema cardiovascular usando técnicas combinadas in vivo e in vitro. A análise química do LVTVSF revelou a presença de vários polifenóis, como a quercetina, miricetina e caempferol. Em ratos com hipertensão induzida pelo L-NAME, o LVTVSF foi capaz de reduzir a pressão arterial média (PAM) quando comparado ao grupo controle (143,7 ± 4,7 versus 172,5 ± 4,7 mmHg), sem alterar a frequência cardíaca (FC). Ratos normotensos no qual foi administrado LVTVSF (10, 30, 90 mg/Kg i.v) aleatoriamente promoveu efeitos hipotensor (-24,0 ± 1,2; -32,4 ± 1,3; -51,4 ± 1,5 %),) e taquicárdico (14,5 ± 2,3; 19,5 ± 1,7; 28,4 ± 2,1%). A resposta hipotensora foi significantemente atenuada após a administração de NG-nitro- L-arginina-metil-éster (L-NAME) (20 mg/Kg i.v.), um inibidor da enzima sintase de óxido nítrico. Em preparações com anéis de artéria mesentérica superior isolada de ratos normotensos pré-contraídos com fenilefrina, o LVTVSF promoveu um efeito vasorelaxante (Emax= 87,22 ± 3,59%). Após a remoção do endotélio vascular o vasorelaxamento foi significativamente atenuado (Emax= 32,07 ± 2,07%, p < 0,05), sugerindo a participação de fatores relaxantes derivados do endotélio. Após a incubação com L-NAME (100 μM) e ODQ (10 μM), um inibidor da ciclase de guanilil solúvel, a resposta relaxante do composto foi significantemente atenuada (Emax.= 22,64 ± 3,74%, p < 0,05 e Emax= 37,08 ± 4,60%, p < 0,05, respectivamente). Resultados similares também foram obtidos em anéis com endotélio, na presença de KCl (20 mM), modulador do efluxo de K+; ou TEA ( 1mM), bloqueador não seletivo dos canais de K+; (Emax= 46,04 ± 9,87%, p < 0,05) e (Emax= 44,40 ± 5,80% p < 0,05). O LVTVSF aumentou os níveis de óxido nítrico em células endoteliais de aorta de coelho. Na presença de caribdotoxina (0,2 μM) e apamina (0,2 μM), bloqueadores dos canais de K+ sensiveis ao cálcio, o efeito relaxante induzido por LVTVSF não foi alterado. A incubação com os inibidores de espécies reativas de oxigênio, n-acetilcisteína (10 mM), tempol (100 μM) e apocinina (10 μM), diminuíram o vasorelaxamento. O efeito vasorelaxante não foi alterado na presença de atropina e indometacina, sugerindo que receptores muscarínicos, bem como metabólitos da via do ácido araquidônico não estão envolvidos neste efeito. Em células endoteliais de aorta de coelho o LVTVSF foi capaz de aumentar a produção de espécies reativas de oxigênio (ROS). Esses resultados em conjunto sugerem que o efeito hipotensor induzido por LVTVSF provavelmente ocorre devido à redução na resistência periférica total, resultado da ativação da via eNOS-NO-GMPc, envolvendo um mecanismo sensível a sinalização redox. Esses efeitos podem ser atribuídos aos flavonóides encontrados no LVTVSF.

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