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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.
71

The potato : composition, non-enzymatic browning and anthocyanins

Rodriguez-Saona, Luis Enrique 04 June 1998 (has links)
Chipping varieties and model systems were used to determine the role of potato constituents on chip color. Composition was evaluated by HPLC and chip color measured using a ColorQuest colorimeter. Reducing sugar (RS) content did not completely explain color quality when present in low concentrations (<60 mg/lOOg). Levels of ascorbic acid, glutamine and a chlorogenic acid isomer, along with RS, showed high correlation with color. Sucrose was a poor estimator of chip color. Model systems used leached potato slices infiltrated with solutions containing sucrose, RS, ascorbic, chlorogenic and amino acids. Linear association of RS with L* and hue angle and quadratic relationship with chroma of chips were found. Ascorbic acid affected chroma and hue at low RS levels while chlorogenic acid was not involved in color development. Red potatoes {Solarium tuberosum and Solarium stenotomum) were evaluated as potential source of natural red colorant. Cultivars (33) were screened for anthocyanin content and qualitative composition. Monomeric anthocyanin content, determined by pH differential, ranged between 4 and 40 mg/lOOg fresh weight (fw) tuber. Varieties 5847-1 and ND04069-4 showed high anthocyanin content (>35 mg/lOOg). Anthocyanin composition was characterized by HPLC, spectral analysis and Mass Spectroscopy (MS). The major anthocyanin was pelargonidin-3-rutinoside-5-glucoside acylated with p-coumaric acid. The presence of glycoalkaloids (α-solanine and α-chaconine) was detected by MS and quantified by HPLC. Varieties NDO4069-4 and 5847-1 showed glycoalkaloid levels of 13 and 7 mg/lOOg fw, respectively. Glycoalkaloids were precipitated from pigment concentrates by alkaline treatment. The best results were obtained at pH 8.0 with 30% monomeric anthocyanin degradation and 90% glycoalkaloid precipitation. The color and pigment stability of chemically related anthocyanin extracts (red-fleshed potatoes and radishes), the effect of pigment purity, and temperature were evaluated in model juices (pH 3.5). Color (CIELch) and anthocyanin degradation was monitored for 65 wks of storage. All model juices showed color similar to FD&C Red # 40. Excellent stability was obtained with all treatments in refrigeration. Anthocyanin structure and extraction method affected pigment stability. At 25°C, higher stability was obtained on juices colored with chemically purified radish anthocyanins (22 wk half-life) and lowest with potato vegetable juice (10 wk half-life). / Graduation date: 1999
72

Effect of post-harvest processing on quality of Sambuci fructus

Brňáková, Lenka January 2015 (has links)
Elderberry is very popular plant, that is due to its beneficial effects to human organism very reputable. The main content substances are flavonoids and anthocyanins. Fruits of this flower are available only seasonally (which is usual for most of flowers), so we have to search for alternative solution of getting them. One of these solutions is conservation. Nowadays there are lots of types of postharvest adjustment, so we have more opportunities to find an optimal concept for every one specific plant. The diploma thesis is focused on assessment of content of phenolic substances harvested in different parts of Hradec Králové. They were conservated at laboratory temperature, elevated (40řC, 60řC) and reduced (-18řC) temperature. Next part of thesis is focused on assessing of the content of anthocyanins in fruits, that had been conservated for 3 years in refrigerator. The theme was finding the best concept of postharvestal adjustment. Despite to the individual places of harvest, there were not mentionable differences found out in content of phenolic substances in fruits. Main differences in content of substances were caused by different temperature of conservating area. With the upper temperature the content of phenolic substances was lower. Storage in the fridge for 3 years did not have any influence...
73

Caracterização de compostos bioativos de três variedades de Pitanga (Eugenia Uniflora L.) / Characterization of the main bioactive compounds of three pitanga varieties (Eugenia Uniflora L.)

Souto, Mariana Magalhães 24 May 2017 (has links)
Os frutos da pitangueira pertencem à família Myrtaceae e podem ser encontrados em três variedades da mesma espécie, reconhecidos de acordo com a cor dos frutos como amarelo, vermelho e roxo. O objetivo deste estudo é caracterizar as três variedades de frutos de pitanga, com relação aos principais carotenoides e compostos fenólicos, e seu comportamento durante o desenvolvimento. Os frutos foram obtidos da região de Campinas (IAC) e fornecidos pela EMBRAPA - (RS). Os extratos metanólico dos frutos foram caracterizados quanto ao conteúdo antocianinas monoméricas, onde somente a variedade roxa, das diferentes plantas e região, apresentou aumento de concentração de antocianinas monoméricas com o desenvolvimento (0,59 a 1,94 mg cy-3-glu eq/g b.s. e 1,43 a 8,47 cy-3-glu eq/g b.s. para o estádio intermediário e maduro, respectivamente. Além disso, a variedade roxa no estádio maduro apresentou maior concentração de fenólicos totais (6,52 a 18,42 mg de AG/g b.s.) quando comparados às outras. O ácido cítrico foi identificado, por CLAE/DAD, como o ácido orgânico majoritário, seguido pelos ácidos succínico e málico, em todas as variedades, com maior concentração no estádio verde. De acordo com a concentração de ácido ascórbico, a pitanga não é uma boa fonte de vitamina C, apresentando valor máximo de 4,0 mg/g b.s no estádio maduro. Os açúcares majoritários encontrados foram a glicose e a frutose. A antocianina majoritária, identificada por LC-ESI-MS/MS, da variedade roxa, no estádio maduro foi a cianidina-3-glicosídeo, com uma variação de 8,05 a 640,53 mg/100g b.s, já o flavonoide majoritário na variedade amarela e vermelha foram miricetina e quercetina em ambas variedades. O carotenoide majoritário identificado por CLAE/DAD, em todas variedades no estádio maduro foi o licopeno, onde a variedade vermelha se destaca pela maior concentração. Dessa forma, o perfil de flavonoides não é alterado com o desenvolvimento, mas é observado uma redução no seu conteúdo nas variedades vermelha e amarela; já a variedade roxa apresenta alteração no perfil de flavonoides, com a expressão de antocianinas no estádio maduro. Por outro lado, o perfil de carotenoides em todas as variedades não sofreu alteração. / The fruits of the pitangueira belong to the family Myrtaceae and can be found in three varieties of the same species, recognized according to the color of the fruits as yellow, red and purple. The aim of this study was characterize the fruits of three pitanga varieties, according to the carotenoids and phenolic compounds composition, and their behavior during ripening. The fruits were obtained from the Campinas region and also provided by EMBRAPA - (RS). Monomeric anthocyaninswere detected only on purple variety, presenting 0.59 to 1.94 mg cy-3-&#927;-glu eq/g d.w. and 1.43 to 8.47 cy-3-&#927;-glu eq/g d.w.) for the intermediate and mature stages, respectively. In addition, the purple variety at the mature stage had the highest total phenolics concentration (6.52 to 18.42 mg of AG/g d.b.) as compared to other varieties. The citric acid was identified as the major organic acid, followed by succinic and malic acids, in all varieties, with a higher concentration in the green stage. According to the concentration of ascorbic acid, pitanga could not be considered a good source of vitamin C, presenting the highest amount of the 4.0 mg/g d.w. at the mature stage. The major soluble sugars found were glucose and fructose. The major anthocyanin of the purple variety, identified by LC-ESI-MS/MS in the mature stage, was cyanidin-3-&#927;-glucoside, ranging from 8.05 to 640.53 mg /100g d.w., whereas the major flavonoids in the yellow and red varieties were myricetin and quercetin. The flavonoid profile was not altered with ripe developing, but a decrease in its content was observed in the red and yellow varieties; on the other hand, the purple variety presented a change in the flavonoid profile, with the expression of anthocyanins in the mature stage. The carotenoids profile in all varieties was the same. The major carotenoid identified by HPLC/DAD, at the mature stage, was lycopene, where the red variety presented the highest concentration.
74

Efeito de extratos ricos em antocianinas ou elagitaninos de amora silvestre (Morus nigra L.), amora preta (Rubus spp), e grumixama (Eugenia brasiliensis Lam) no crescimento e na expressão de genes e miRNAs de diferentes linhagens de céluas humanas de câncer de mama. / Effects of extracts rich in anthocyanins or ellagitans from mulberry (Morus nigra L.), blackberry (Rubus spp) and grumixama (Eugenia brasiliensis Lam) on cellular growth and gene and miRNAs expression from distinctive human breast cancer cell lines.

Costa, Gabriela Rezende 28 September 2017 (has links)
O câncer de mama caracteriza-se globalmente como a neoplasia de maior incidência e mortalidade na população feminina. Antocianinas e elagitaninos presentes em frutas como as berries destacam-se por seu promissor efeito protetor em diferentes estágios do desenvolvimento do câncer de mama. Grumixama (G; Eugenia brasiliensis Lam) é uma espécie de cereja nativa do Brasil que assim como as amora-preta (AP; Rubus spp) e silvestre (AS; Morus nigra L.) contém alto teor de antocianinas e elagitaninos. Poucos estudos focaram na ação anticâncer destas berries no câncer de mama. Portanto, o objetivo do presente estudo foi avaliar os efeitos de extratos ricos em antocianinas ou elagitaninos de G, AP e AS no crescimento e na expressão de genes e miRNAs das linhagens de células humanas de câncer de mama MCF-7 (receptor de hormônio positiva) e MDA-MB 231 (receptor de hormônio negativa). Não se observou citotoxicidade após 72 e 96 horas de tratamento com os extratos (25-200&#181g/mL) ricos em antocianinas (ASANT, APANT e GANT) ou elagitaninos (APELA e GELA), em ambas as linhagens celulares. Após 72 horas de tratamento, GANT e APANT induziram parada de ciclo celular em G0/G1 (12,5 e 50&#181g/mL, p<0,05) em células MCF-7. Após 96h, ASANT, APANT e GANT induziram parada de ciclo celular em G0/G1 (12,5 e 50&#181g/mL; p<0,05) nessas mesmas células. Entretanto, na concentração de 200&#181g/mL apenas GANT induziu parada em G0/G1 (72 e 96h; p<0,05). Em células MDA-MB 231, após 96h APANT e GANT induziram parada de ciclo celular em G0/G1 nas concentrações testadas (12,5, 50 e 200&#181g/mL, p<0,05), assim como ASANT nas concentrações de 12,5 e 50&#181g/mL (p<0,05). Em células MCF-7, após 72h APELA e GELA induziram aumento da proporção de células em subG0 (200&#181g/mL, p<0,05). Em MDA-MB 231, após 72 e 96h, APELA e GELA (200&#181g/mL) induziram aumento da proporção de células em subG0 (p<0,05) e parada em G0/G1 (p<0,05). Em células MCF-7, GANT induziu morte celular por apoptose (p<0,05) após 72 e 96h de tratamento. Entretanto, em MDA-MB 231 os extratos ricos em antocianinas não induziram morte celular. Em células MCF-7, após 96h GELA e APELA induziram principalmente necrose (p<0,05). Em MDA-MB 231, APELA e GELA induziram apoptose (p<0,05) após 72 e 96h. Em células MDA-MB 231, após 72h de tratamento foi observada inibição da proliferação celular por GELA, GANT e APELA (200&#181g/mL; p<0,05). Em células MDA-MB 231, 48h de tratamento com GELA; GANT e APELA (200&#181g/mL) aumentaram a expressão 5 genes (ESR2, FOXA1, JUN, PTGS2,VEGFA) e inibiram a expressão de 10 genes (ADAM23, ATM, BCL2, CDH1, EGF, GLI1, ID1, MKI67, SNAI2 e THBS1) correlacionados ao câncer de mama. Adicionalmente, GELA; GANT e APELA (200&#181g/mL) induziram aumento da expressão de miR- 210(p<0,05) e APELA (200&#181g/mL) reduziu a expressão de miRNA 19a/b (p<0,05) em células MDAMB 231. Coletivamente estes resultados sugerem que antocianinas de grumixama e elagitaninos de amora preta e grumixama apresentam potencial efeito protetor contra o câncer de mama. Adicionalmente, essa ação anticarcinogênica pode ser mediada por indução de morte celular, mais especificamente apoptose, redução de proliferação celular e modulação da expressão de genes e miRNAs relacionados ao câncer de mama. / Breast cancer is characterized as the neoplasia with the highest incidence and mortality rates in women worldwide. Anthocyanins and ellagitannins present in certain fruits, such as berries, stand out for their promising protective effect at different stages of breast cancer development. Grumixama (G; Eugenia brasiliensis Lam), a cherry species from Brazil, as well as blackberry (AP; Rubus spp) and mulberry (AS; Morus nigra L.) contain elevated concentrations of anthocyanins and ellagitannins. Few studies focused on the anticarcinogenic action of these berries in breast cancer development. Therefore, the aim of the present study was to evaluate the effects of extracts rich in anthocyanins or ellagitannins from G, AP and AS on cellular growth and genes and miRNAs expression in human MCF-7 (hormone receptor positive) and MDA-MB 231 (hormone receptor negative) cell lines. No cytotoxicity was observed after 72 and 96 hours of treatment with extracts rich in anthocyanin (25-200 &#181g/mL) (ASANT, APANT and GANT) or ellagitannins (APELA and GELA) in both cell lines. After 72 hours of treatment, GANT and APANT induced cell cycle arrest at G0/G1 (12.5&#181g/mL and 50&#181g/mL, p<0.05) in MCF-7 cells. After 96h, ASANT, APANT and GANT induced cycle arrest at G0/G1 (12.5 and 50&#181g/mL; p<0.05) in MCF-7 cells. However, at 200&#181g/mL, only GANT induced G0/G1 (72 and 96h; p<0.05). In MDA-MB 231 cells, after 96h APANT and GANT induced cell cycle arrest at G0/G1 with the three tested concentrations (12.5, 50 and 200&#181g/mL, p<0.05), as well as ASANT at concentrations 12,5 and 50&#181g/mL (p <0.05). In MCF-7 cells, after 72h APELA and GELA induced an increase in the proportion of cells in subG0 (200&#181g/mL, p<0.05). In MDA-MB 231, after 72 and 96h, APELA and GELA (200&#181g/mL) induced an increase in the proportion of cells in subG0 (p<0.05) and cell cycle arrest in G0/G1 (p<0.05). In MCF-7 cells, GANT induced apoptosis (p<0.05) after 72 and 96h of treatment. However, in MDA-MB 231, extracts rich in anthocyanins did not induce cell death. In MCF-7 cells, after 96h GELA and APELA induced mainly necrosis (p<0.05). In MDA-MB 231, APELA and GELA induced apoptosis (p<0.05) after 72 and 96h. In MDA-MB 231 cells, inhibition of cell proliferation by GELA, GANT and APELA (200?g/mL; p<0.05) was observed after 72h of treatment. In MDA-MB 231 cells, treatment for 48h with GELA, GANT and APELA (200&#181g) increased expression of 5 genes (ESR2, FOXA1, JUN, PTGS2, VEGFA) and inhibited expression of 10 genes (ADAM23, ATM, BCL2, CDH1, EGF, GLI1, ID1, MKI67, SNAI2 and THBS1) correlated with breast cancer. In addition, GELA; GANT and APELA (200&#181g/mL) induced increased expression of miR-210 (p<0.05) and APELA (200&#181g/mL) reduced the expression of miRNA 19a/b (p<0.05) in MDA-MB cells 231. Collectively these results suggest that anthocyanins of grumixama and ellagitannins of blackberry and grumixama have potential protective effect against breast cancer. Additionally, this anticarcinogenic action can be mediated by induction of cell death, more specifically apoptosis, reduction of cell proliferation and modulation of the expression of genes and miRNAs related to breast cancer.
75

Estudo comparativo do perfil metabolômico e proteômico de uvas (Vitis vinifera) durante o processo de maturação utilizando ferramentas bioanalíticas / Comparative study of metabolomic and proteomic profiles of grapes (Vitis vinifera) during ripening using bioanalytical tools

Fraige, Karina 13 July 2012 (has links)
A análise da composição química das uvas é de grande importância para avaliar a data da colheita e a produção de vinhos de qualidade. O estudo do metabolismo das uvas é essencial para definirem-se em quais etapas os metabólitos são produzidos, assim como as proteínas e genes que regulam esses processos. Açúcares, polifenóis e ácidos orgânicos são importantes classes de metabólitos relacionados com o desenvolvimento de uvas. Os açúcares são os compostos que primeiramente indicam a data de colheita, sendo substâncias-chave em diversos processos biológicos. Os polifenóis tem se destacado por sua atividade antioxidante, além de participarem dos mecanismos de defesa da planta. Os ácidos orgânicos são responsáveis pela qualidade organoléptica e estão envolvidos em vários processos metabólicos. As proteínas não contribuem de forma significativa para o valor nutricional, mas são importantes marcadores de variedade para verificar adulterações de vinhos. O Rio Grande do Sul é responsável por grande parte das uvas produzidas no país, e recentemente o Vale do São Francisco tem se destacado na produção destas frutas. Em regiões do Sudeste um manejo de podas diferenciado vem sendo feito para a obtenção de uvas com bons índices de maturação e resistência a doenças fúngicas. Uvas produzidas em Água Vermelha e Louveira, interior de São Paulo, foram estudadas durante a maturação com relação a análises físico-químicas, perfil proteômico, por eletroforese bidimensional e espectrometria de massas, e perfil metabolômico de antocianinas, polifenóis não-antociânicos, ácidos orgânicos e açúcares por técnicas cromatográficas e eletroforéticas acopladas a detectores por arranjo de diodos e/ou espectrometria de massas. Os resultados foram analisados por ferramentas de análise multivariada e comparados com uvas maduras das regiões Sul e Nordeste. Foram observadas tendências de agrupamento das uvas verdes devido à maior acidez e das uvas maduras devido à maior concentração de antocianinas e açúcares, sendo que o perfil de antocianinas pode ser utilizado como marcador de origem varietal. Em termos do perfil proteômico foi possível estabelecer diferenças entre variedades de uvas, além de uma tendência com relação à origem geográfica. Foram identificadas 74 proteínas relacionadas principalmente, às funções de defesa e resposta a stress, metabolismo de carboidratos e metabolismo energético. / Analysis of the chemical composition of grapes is very important to evaluate harvest time and production of high quality wines. The study of grape metabolism is essential to define in which stages metabolites are produced, as well as proteins and genes that regulate these processes. Sugars, polyphenols and organic acids are important classes of metabolites related with grape development. Sugars are compounds that primarily indicate harvest time, and they are key substances in various biological processes. Polyphenols have been noted for its antioxidant activity, also for taking part in mechanisms of plant defense. Organic acids are responsible for organoleptic quality, and they are evolved in diverse metabolic processes. Proteins do not contribute significantly to the nutritional value, but they are important variety markers to verify adulterations of wines. Rio Grande do Sul is responsible for most of the grapes produced in Brazil, and recently Vale do São Francisco has received attention because of the production of these fruits. In some regions of Southeast a different pruning handle has started to obtain grapes with good levels of ripeness and resistance in developing fungal diseases. Grapes cultured in Água Vermelha and Louveira, São Paulo State, were studied during ripening in relation to physical-chemical analysis, proteomic profile, by two-dimensional electrophoresis and mass spectrometry; the metabolomic profile of anthocyanins, non-anthocyanin polyphenols, organic acids and sugars by chromatographic and electrophoretic techniques coupled to diode array and/or mass spectrometry detectors. The results were analyzed by multivariate analysis and compared with those of mature grapes from South and Northeast regions. The data show clustering of green grapes due to higher acidity and clusters of mature grapes due to higher anthocyanin and sugars concentrations, and the profile of anthocyanins can be used as a varietal marker. Considering the proteomic profile, it was possible to group different varieties of grapes with a trend in relation to geographical origin being also observed. It was identified 74 proteins related, mainly, to defense and stress response, carbohydrate metabolism and energetic metabolism.
76

Padrões de pigmentação e influência de fatores hormonais na pigmentação da corona de Passiflora spp. (Passifloraceae) / Pigmentation patterns and influence of hormonal factors on the pigmentation of Passiflora spp. (Passifloraceae) corona

Monte-Bello, Carolina Cassano, 1987- 05 September 2018 (has links)
Orientador: Marcelo Carnier Dornelas / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-09-05T12:21:39Z (GMT). No. of bitstreams: 1 Bello_CarolinaCassanoMonte_M.pdf: 4096413 bytes, checksum: 81120541bfee4c3700b982f05823abef (MD5) Previous issue date: 2013 / Resumo: A grande diversidade floral presente entre as espécies de Passiflora é o produto de diversas adaptações à grande variedade de polinizadores. A presença de um verticilo de filamentos denominado corona, entre os verticilos de pétalas e estames, é uma das principais características florais em Passiflora. Estes filamentos são de fundamental importância na interação com polinizadores e suas características (tamanho, forma, cor) estão sob forte pressão de seleção. A coloração dos filamentos da corona pode ter a mesma pigmentação do perianto, ou possuir cores contrastantes. Geralmente esta pigmentação é dada pela presença de antocianinas, garantindo um grande espectro de cores para as flores. Com frequência há uma distribuição diferencial dos pigmentos ao longo dos filamentos da corona. O estudo desta distribuição diferencial dos pigmentos permitiu a identificação de pelo menos 5 tipos de padrões de pigmentação da corona em Passiflora, sendo eles: "dégradée", bandeado e ponteado, bem como pigmentação uniforme e ausência aparente de pigmentação. Devido à grande importância da pigmentação da corona para o sucesso reprodutivo em Passiflora, propôs-se estudar a influência hormonal no processo de pigmentação desta estrutura. Pretendeu-se identificar o efeito da concentração de auxinas (por meio da aplicação de diferentes concentrações de ácido 2,4-diclorofenoxiacético, 2,4-D, e um inibidor do transporte polar de auxina, o ácido naftil-ftalâmico, NPA) e de giberelinas (por meio da aplicação de diferentes concentrações de ácido giberélico, GA3, e de um inibidor de sua síntese, o paclobutrazol, PACLO) na pigmentação de filamentos da corona em desenvolvimento das espécies de P. edulis, P. morifolia e P. suberosa, sendo os tratamentos hormonais realizados in vitro e in planta. Após as aplicações hormonais, os pigmentos florais foram analisados por espectrofotometria UV-vis. A aplicação de GA3 causou aumento da pigmentação floral e a aplicação de um inibidor de sua síntese, PACLO, causou a redução da pigmentação. A Aplicação de auxina (2,4-D) e um inibidor do seu transporte polar (NPA) tiveram efeitos similares no sentido da redução da pigmentação. Determinou-se o padrão de expressão, mediante RT-PCR e hibridização in situ, do gene MYB-R2R3/PACEPS7022E07 de P. suberosa, potencialmente envolvida na modulação da síntese de antocianinas, e demonstrou-se que o mesmo é expresso preferencialmente em órgãos florais / Abstract: The floral diversity present in the species of Passiflora is the product of several adaptations to the wide variety of pollinators. The presence of a whorl of filaments called corona, between the whorls of stamens and petals, is a major floral trait in Passiflora. These filaments are of fundamental importance in the interaction of pollinators and their characteristics (size, shape, color) are under strong selective pressure. The pigmentation of the corona filaments might have the same color of the perianth, or have contrasting colors. Generally the pigmentation is given by the presence of anthocyanins, ensuring a wide range of colors for the flowers. Often there is a differential distribution of pigment throughout the corona filament. Studying a variety of patterns of corona pigmentation, it was established that there are at least 5 types of pigmentation patterns in Passiflora: "dégradée", stripped and dotted, as well as uniformly pigmented and non-pigmented. Due to the great importance of the corona pigmentation for the reproductive success in Passiflora, we proposed to study the influence of hormones on the pigmentation process of this structure. In order to identify the effect of the application of auxins (through different doses of 2,4-dichlorophenoxyacetic acid, 2,4-D, and of the inhibitor of auxin polar transport, naphthyl ftalamic acid, NPA) and gibberellins (through the application of different doses of gibberellic acid, GA3, and its synthesis inhibitor, paclobutrazol, PACLO) in pigmentation of corona filament developing of species P. edulis, P. morifolia and P. suberosa, and hormonal treatments performed in vitro, in cultured corona filaments, and in planta spraying floral buds. For the verification of the effect of hormone applications, the flower pigments were analyzed by spectrophotometer UV-vis where only GA3 caused increased floral pigmentation contrary to PACLO, which caused the reduction of pigmentation. The auxin 2,4-D and an inhibitor of polar auxin transport, NPA had the same effect, reducing the floral pigmentation. We determined the pattern of expression (by RT-PCR and in situ hybridization) of the R2R3-MYB/PACEPS7022E07 gene of P. suberosa, potentially involved in the regulation of anthocyanin synthesis, demonstrating that it is expressed preferentially in floral organs / Mestrado / Biologia Vegetal / Mestra em Biologia Vegetal
77

Estudo comparativo do perfil metabolômico e proteômico de uvas (Vitis vinifera) durante o processo de maturação utilizando ferramentas bioanalíticas / Comparative study of metabolomic and proteomic profiles of grapes (Vitis vinifera) during ripening using bioanalytical tools

Karina Fraige 13 July 2012 (has links)
A análise da composição química das uvas é de grande importância para avaliar a data da colheita e a produção de vinhos de qualidade. O estudo do metabolismo das uvas é essencial para definirem-se em quais etapas os metabólitos são produzidos, assim como as proteínas e genes que regulam esses processos. Açúcares, polifenóis e ácidos orgânicos são importantes classes de metabólitos relacionados com o desenvolvimento de uvas. Os açúcares são os compostos que primeiramente indicam a data de colheita, sendo substâncias-chave em diversos processos biológicos. Os polifenóis tem se destacado por sua atividade antioxidante, além de participarem dos mecanismos de defesa da planta. Os ácidos orgânicos são responsáveis pela qualidade organoléptica e estão envolvidos em vários processos metabólicos. As proteínas não contribuem de forma significativa para o valor nutricional, mas são importantes marcadores de variedade para verificar adulterações de vinhos. O Rio Grande do Sul é responsável por grande parte das uvas produzidas no país, e recentemente o Vale do São Francisco tem se destacado na produção destas frutas. Em regiões do Sudeste um manejo de podas diferenciado vem sendo feito para a obtenção de uvas com bons índices de maturação e resistência a doenças fúngicas. Uvas produzidas em Água Vermelha e Louveira, interior de São Paulo, foram estudadas durante a maturação com relação a análises físico-químicas, perfil proteômico, por eletroforese bidimensional e espectrometria de massas, e perfil metabolômico de antocianinas, polifenóis não-antociânicos, ácidos orgânicos e açúcares por técnicas cromatográficas e eletroforéticas acopladas a detectores por arranjo de diodos e/ou espectrometria de massas. Os resultados foram analisados por ferramentas de análise multivariada e comparados com uvas maduras das regiões Sul e Nordeste. Foram observadas tendências de agrupamento das uvas verdes devido à maior acidez e das uvas maduras devido à maior concentração de antocianinas e açúcares, sendo que o perfil de antocianinas pode ser utilizado como marcador de origem varietal. Em termos do perfil proteômico foi possível estabelecer diferenças entre variedades de uvas, além de uma tendência com relação à origem geográfica. Foram identificadas 74 proteínas relacionadas principalmente, às funções de defesa e resposta a stress, metabolismo de carboidratos e metabolismo energético. / Analysis of the chemical composition of grapes is very important to evaluate harvest time and production of high quality wines. The study of grape metabolism is essential to define in which stages metabolites are produced, as well as proteins and genes that regulate these processes. Sugars, polyphenols and organic acids are important classes of metabolites related with grape development. Sugars are compounds that primarily indicate harvest time, and they are key substances in various biological processes. Polyphenols have been noted for its antioxidant activity, also for taking part in mechanisms of plant defense. Organic acids are responsible for organoleptic quality, and they are evolved in diverse metabolic processes. Proteins do not contribute significantly to the nutritional value, but they are important variety markers to verify adulterations of wines. Rio Grande do Sul is responsible for most of the grapes produced in Brazil, and recently Vale do São Francisco has received attention because of the production of these fruits. In some regions of Southeast a different pruning handle has started to obtain grapes with good levels of ripeness and resistance in developing fungal diseases. Grapes cultured in Água Vermelha and Louveira, São Paulo State, were studied during ripening in relation to physical-chemical analysis, proteomic profile, by two-dimensional electrophoresis and mass spectrometry; the metabolomic profile of anthocyanins, non-anthocyanin polyphenols, organic acids and sugars by chromatographic and electrophoretic techniques coupled to diode array and/or mass spectrometry detectors. The results were analyzed by multivariate analysis and compared with those of mature grapes from South and Northeast regions. The data show clustering of green grapes due to higher acidity and clusters of mature grapes due to higher anthocyanin and sugars concentrations, and the profile of anthocyanins can be used as a varietal marker. Considering the proteomic profile, it was possible to group different varieties of grapes with a trend in relation to geographical origin being also observed. It was identified 74 proteins related, mainly, to defense and stress response, carbohydrate metabolism and energetic metabolism.
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Analysis of flavor precursors in radish and radish color extracts

Kucza, Myriam M. 13 December 1996 (has links)
Radish anthocyanin extract has potential as a natural colorant because of its pigment stability and attractive red hue. Presence of undesirable aroma compounds could limit its applications in foods. The pungent principle of radish, 4-methylthio-3-butenyl isothiocyanate (MTBI), is produced enzymatically upon cell injury from its glucosinolate precursor, 4-methylthio-3-butenyl glucosinolate (MTBG), and undergoes subsequent degradation to produce a number of volatiles. To evaluate the potential of flavor formation, juices were prepared from winter and spring radish cultivars. Whole radishes, peels and flesh, as well as radish extracts, were analyzed for glucosinolates and isothiocyanates. Aroma intensities of radish juice extracts were evaluated using sensory analysis. MTBI was monitored by HPLC (detection level 160 ppb). MTBG was extracted from freeze-dried radish tissue with boiling methanol, purified by anion exchange and enzymatically desulfated. DesulfoMTBG was quantified by HPLC, using desulfosinigrin as internal standard. Identification was performed by fast atom bombardment and electrospray mass spectroscopy. MTBI formation was higher in winter than in spring cultivars (1.5-2.8 and 0.8-1.3 mg/100g fresh weight, respectively), and higher in flesh than in peels. MTBG ranged from 30-65 mg (spring cultivars) to 260-320 mg/100g fresh weight (winter cultivars) with greater concentration in peels than in flesh. Isothiocyanates and glucosinolates were not detected in radish juices. Overall aroma intensities of radish juice concentrates, diluted to 150, 300, 600 and 1200 mg anthocyanin/L in water, were rated using a 16-point scale. Radish concentrates from cultivars Fuego (pigmented peels) and Red Meat Takii (whole red flesh) were compared to commercial red cabbage and radish colorants. Aroma intensities followed first order relationships with anthocyanin concentrations. The commercial colorants were rated slight to moderate, while radish extracts (Fuego and Takii) were rated moderate to large. The aroma intensity of red flesh radish extract was more potent than those prepared from radish peels. Further work includes development of purification techniques which would provide an odorless aqueous extract. / Graduation date: 1997
79

Reactions of anthocyanins and o-quinones in model systems and foods

Afanas'yev, Dmytro 11 1900 (has links)
Molecules of anthocyanins and quinones possess distinctive electrophilic character, which is demonstrated by their facile reactions with nucleophiles such as sulfite, thiols, amines and water. In food systems, one of their likely targets would be nucleophilic centers in the side chains of amino acids. Our experiments revealed that on a short-term exposure (1 72 h) to free amino acids in solutions with pH < 7 glycosides of cyanidin and quinones of phenolic acids did not yield nucleophilic addition products with most of the amino acids. A notable exception was cysteine, which reacted with oxidized phenolic acids and caused anthocyanin bleaching at elevated temperature. Thermodynamic aspects of the nucleophilic addition reactions were investigated with the aid of computational chemistry. We have also found that enzymatic browning in apricot puree does not lead to trans-cis -carotene isomerization, contrary to some previous reports. Increased availability of -carotene for extraction was recorded for browned apple- and pear-apricot purees in comparison with the non-browned purees. / Food Science and Technology
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Analysis and entrapment of select antioxidants from chokecherry and Saskatoon berry fruits

Konecsni, Kelly Alyson 03 June 2011
The major objectives of this research were to produce a phenolic rich isolate from two locally grown Saskatchewan fruits, chokecherries and saskatoons, develop an encapsulation system for the phenolic isolate, and test this system for the delivery of the phenolic isolate in an animal (rat) model. Natural phenolic compounds present in plants such as fruits have antioxidant and free radical scavenging activities, which have been proposed to have health benefits. The extraction of these compounds from plants is commonly performed using methanol despite being toxic to both humans and animals. As such, ethanol was investigated for its ability to extract phenolics from plants as a food safe alternative to methanol. Phenolic extraction from chokecherries with ethanol:formic acid:water (EFW) resulted in higher concentrations (9.83 mg gallic acid equivalents (GAE)/g fresh weight) than with methanol:formic acid:water (MFW) (7.97 mg GAE/g fresh weight). Results from saskatoons showed similar phenolic levels of 4.26 and 4.21 mg GAE/g fresh weight with MFW and ethanol (EFW), respectively. These results showed that EFW was a suitable substitute for MFW in phenolic compound isolation from chokecherries and saskatoons, and could be used to produce extracts that were safe for use in foods and feeds. High performance liquid chromatography with photodiode array detection (HPLC-PDA) was used to determine the phenolic compound composition of the raw fruits and their phenolic rich isolates. Chlorogenic acid was identified in both chokecherry and saskatoon samples, and rutin was also shown to be present in saskatoons. These identifications were based on the relative retention time and ultra violet-visual spectra comparisons to standards. Solid phase extraction (SPE) using Amberlite XAD-16 was employed to produce phenolic isolates from chokecherries and saskatoons. HPLC-PDA results determined that there was a ~2.7x and ~1.6x increase in peak area for chokecherries and saskatoons, respectively when SPE was employed. The antioxidant activity of the extracts and isolates was determined using in vitro radical scavenging tests including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2´-azinobis-3-ethylbenzthiazoline-sulphonic acid (ABTS). The EFW chokecherry extract and isolate had the highest overall free radical scavenging activity. Crude fruit extracts exhibited lower free radical scavenging values compared to the isolate samples in both of the assays performed. The fruit phenolic isolates were encapsulated in chitosan (CH) sodium tripolyphosphate (TPP) nanoparticles at a ratio of 4.0:1.0 (CH:TPP). HPLC-PDA was used to determine the entrapment efficiency of phenolic isolates to be 15.9 ± 2.7% and 23.0 ± 7.1% for chokecherries and saskatoons, respectively. Characteristics such as the size, surface potential and phenolic release were determined for the two fruit isolate containing nanoparticles. The size of the nanoparticles were 527.90 ± 74.57 nm and 443.03 ± 15.79 nm for chokecherries and saskatoons, respectively. Both of the nanoparticle systems had positive surface charges at 52.70 ± 2.93 mV and 54.43 ± 1.27 mV for chokecherries and saskatoons, respectively. The release properties of the CH:TPP nanoparticles containing fruit phenolics were examined in enzymatic simulated intestinal fluid and resulted in ~23% and ~28% release of chokecherry and saskatoon phenolics, respectively. Saskatoon phenolic isolates and isolates encapsulated in CH:TPP were gavage fed to rats (six animals in each of the two groups) at a dosage rate of 276.36 ± 9.74 mg/kg body weight. The saskatoon isolate contained 12.44 ± 0.44 mg/kg body weight anthocyanins (~3.30 mg anthocyanin per rat). These animals were sacrificed after 1 h and all stomach tissue samples in each of the treatment groups contained detectable levels of anthocyanins. In the small intestine tissues all six of the saskatoon isolate and three of the encapsulated isolate groups had detectable amounts of anthocyanins, while in the large intestine tissue, only one sample from the isolate group showed detectable amounts of anthocyanins. Although other tissues were tested (brain, heart, kidney and liver), anthocyanins were not detected. Therefore anthocyanins were detected in the gastrointestinal tract of both of the treatment groups. The research performed therefore illustrated that phenolic compounds can be extracted from fruit sources using EFW and can be successfully encapsulated in chitosan tripolyphosphate capsules allowing for targeted delivery in an animal model.

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