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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

In silico studies of the effect of phenolic compounds from grape seed extracts on the activity of phosphoinositide 3-kinase (PI3K) and the farnesoid x receptor (FXR)

Vaqué Marquès, Montserrat 19 December 2007 (has links)
In silico studies of the effect of phenolic compounds from grape seed extracts on the activity of phosphoinositide 3-kinase (PI3K) and farnesoid X receptor (FXR)Montserrat Vaqué Marquès En aquesta tesis es pretén aplicar metodologies computacionals (generació de farmacòfors i docking proteïna lligand) en l'àmbit de la nutigenòmica (ciència que pretén entendre, a nivell molecular, com els nutrients afecten la salut). S'aplicaran metodologies in silico per entendre a nivell molecular com productes naturals com els compostos fenòlics presents en la nostra dieta, poden modular la funció d'una diana comportant un efect en la salut. Aquest efecte es creu que podria ser degut a la seva interacció directa amb proteïnes de vies de senyalització molecular o bé a la modificació indirecta de l'expressió gènica. Donat que el coneixement de l'estructura del complex lligand-receptor és bàsic per entendre el mecanisme d'acció d'aquests lligands s'aplica la metodologia docking per predir l'estructura tridimensional del complex. En aquest sentit, un dels programes de docking és AutoGrid/AutoDock (un dels més citats). No obstant, l'automatització d'AutoGrid/AutoDock no és trivial tan per (a) la cerca virtual en una llibreria de lligands contra un grup de possibles receptors, (b) l'ús de flexibilitat, i (c) realitzar un docking a cegues utilitzant tota la superfície del receptor. Per aquest motiu, es dissenya una interfície gràfica de fàcil ús per utilitzar AutoGrid/AutoDock. Blind Docking Tester (BDT) és una aplicació gràfica que s'executa sobre quatre programes escrits en Fortran i que controla les condicions de les execucions d'AutoGrid i AutoDock. BDT pot ser utilitzat per equips d'investigadors en el camp de la química i de ciències de la vida interessats en dur a terme aquest tipus d'experiments però que no tenen suficient habilitats en programació. En la modulació del metabolisme de la glucosa, treballs in vivio i in vitro en el nostre grup de recerca s'han atribuït els efectes beneficiosos de l'extracte de pinyol de raïm en induir captació de glucosa (punt crític pel manteniment de l'homeostasis de la glucosa). No obstant alguns compostos fenòlics no tenen efecte en la captació de la glucosa, d'altres l'inhibeixen reversiblement. En alguns casos aquesta inhibició és el resultat de la competició dels compostos fenòlics amb ATP pel lloc d'unió de l'ATP de la subunitat catalítica de la fosfatidil inositol 3-kinasa (PI3K). Estudis recents amb inhibidors específics d'isoforma han identificat la p110α (la subunitat catalítica de PI3Kα) com la isoforma crucial per la captació de glucosa estimulada per insulina en algunes línies cel·lulars. Els programes computacionals han estat aplicats per tal de correlacionar l'activitat biològica dels compostos fenòlics amb informació estructural per obtenir una relació quantitativa estructura-activitat (3D-QSAR) i obtenir informació dels requeriments estructura-lligand per augmentar l'afinitat i/o selectivitat amb la diana (proteïna). Tot hi haver-se demostrat que l'adició d'extractes de compostos fenòlics en l'aliment pot tenir en general un benefici per la salut, s'ha de tenir en compte que l'estudi 3D-QSAR (construït a partir d'inhibidors sintètics de p110α) prediu que algunes d'aquestes molècules poden agreujar la resistència a la insulina en individus susceptibles dificultant la capatació de glucosa en múscul i teixit adipós i, per tant, produir un efecte secundari indesitjat. Resultats en el nostre grup de recerca han demostrat que compostos fenòlics presents en extractes de llavor de raïm incrementen l'activitat del receptor "farnesoid x receptor" (FXR) de manera dosi depenent quan el lligand natural de FXR (CDCA) és present. Les metodologies in silico, docking i 3D-QSAR, han estat aplicades juntament amb dades biològiques d'agonistes no esteroidals de FXR que s'uneixen a un lloc d'unió proper però diferent al lligand esteroidal 6CDCA. Els resultats han mostrat que els compostos fenòlics no són capaços d'activar FXR per ells mateixos però poden afegir noves interaccions que estabilitzarien la conformació activa de FXR en presència del lligand natural CDCA. Els compostos fenòlics podrien induir canvis conformacionals específics que augmentarien l'activitat de FXR. In silico studies of the effect of phenolic compounds from grape seed extracts on the activity of phosphoinositide 3-kinase (PI3K) and farnesoid X receptor (FXR)Montserrat Vaqué Marquès This thesis was written with the aim of applying computational methods that have already been developed for molecular design and simulation (i.e. pharmacophore generation and protein-ligand docking) to nutrigenomics. So, in silico tools that are routinely used by the pharmaceutical industry to develop drugs have been used to understand, at the molecular level, how natural products such as phenolic compounds (i.e. molecules that are commonly found in fruits and vegetables) can improve health and prevent diseases. Therefore, we first focused on predicting the structure of protein-ligand complexes. The docking algorithms can use the individual structures from receptor and ligand to predict (1) whether they can form a complex and (2) if so, the structure of the resulting complex. This prediction can be made, for instance, with AutoGrid/AutoDock, the most cited docking software in the literature. The automation of AutoGrid/AutoDock is not trivial for tasks such as (1) the virtual screening of a library of ligands against a set of possible receptors; (2) the use of receptor flexibility and (3) making a blind-docking experiment with the whole receptor surface. Therefore, in order to circumvent these limitations, we have designed BDT (i.e. blind-docking tester; http://www.quimica.urv.cat/~pujadas/BDT), an easy-to-use graphic interface for using AutoGrid/AutoDock. BDT is a Tcl/Tk graphic front-end application that runs on top of four Fortran programs and which controls the conditions of the AutoGrid and AutoDock runs. As far as the modulation of the glucose metabolism is concerned, several in vivo and in vitro results obtained by our group have shown that grape seed procyanidin extracts (GSPE) stimulate glucose uptake in 3T3-L1 adipocytes and thus help to maintain their glucose homeostasis. In contrast, it is also well known that although some phenolic compounds do not affect glucose uptake, others reversibly inhibit it in several cell lines. Moreover, for at least some of these phenolic compounds, this inhibition is the result of their competition with ATP for the ATP-binding site in p110α (i.e. the α isoform of the catalytic subunit of phosphoinositide 3-kinase or PI3Kα). Furthermore, recent studies with isoform-specific inhibitors have identified p110α as the crucial isoform for insulin-stimulated glucose-uptake in some cell lines. Therefore, although it has been proved that the addition of phenolic compound extracts to food can have an overall benefit on health, it should be taken into account that some of these molecules may exacerbate insulin resistance in susceptible individuals via impaired glucose uptake in muscle and adipose tissues and, therefore, produce an undesirable side effect. In this context, we have applied computational approaches (i.e. protein-ligand docking and 3D-QSAR) to predict the IC50 (i.e. the concentration that reduces the p110α activity to 50%). Our results agree with previous experimental results and predict that some compounds are potential inhibitors of this enzyme. Recent results in our research group have demonstrated that the phenolic compounds in GSPE increase the activity of the farnesoid X receptor (i.e. FXR) in a dose-dependent way when the natural ligand of FXR (i.e. CDCA) is also present. The phenolic compounds might induce specific conformational changes that increase FXR activity and then contribute to cardioprotection through mechanisms that are independent of their intrinsic antioxidant capacities but that involve direct interaction with FXR to modulate gene expression. Taking into account this hypothesis a 3D-QSAR analysis was made in an attempt to understand how phenolic compounds activate FXR. So, our results explain why phenolic compounds cannot activate FXR by themselves and how they can add new interactions to stabilize the active conformation of FXR when its natural ligand (i.e. CDCA) is present. Therefore, we proposed a mechanism of FXR activation by dietary phenolic compounds in which they may enhance bile acid-bound FXR activity.
12

Analysis and entrapment of select antioxidants from chokecherry and Saskatoon berry fruits

Konecsni, Kelly Alyson 03 June 2011 (has links)
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.
13

Bioremediation of creosote-treated wood waste

Zhang, Bopeng 27 October 2010 (has links)
Currently, creosote-treated wood waste is mainly landfilled but the Province of Nova Scotia would prefer to see the waste converted to a valuable product. Bioremediation provides a treatment option for creosote-treated wood waste and the production of a value-added product that would have economic and environmental benefits. Composting technique can be used to degrade the contaminants and convert wood waste into humus and nutrients rich product and reduces the waste volume. The aim of this study was, therefore, to test the efficiency of the composting process in degrading the creosote in the contaminated wood waste. A laboratory scale bioremediation process was carried out in three specially designed in-vessel bioreactors equipped with thermo-insulating outer layer, mixing units, controlled aeration units, thermocouples a data logger and a computer. The three bioreactors were used as replicates. The ability of three thermophilic and cellulolytic microorganisms (T. curvata, T. aurantiacus and T. fusca) to degrade lignocellulose substrate was tested.
14

THE EFFECTS OF COOKED COMMON BEANS ON DSS-INDUCED COLITIS IN MICE

ZHANG, PENGLIHUI CLAIRE 13 September 2012 (has links)
This thesis is an investigation of the effects of whole beans, with different levels of phenolics level, on colonic inflammation in mice. C57BL/6 male mice were fed a basal diet (BD) supplemented with or without 20% bean flour for 3 weeks. Colitis was induced by 2% dextran sulphate sodium (DSS) in mice drinking water. Phenolic determinations of the bean flours revealed that within each pair of beans, the darker bean had higher phenolic content and antioxidant activity compared to the lighter one. In addition, only coloured beans had anthocyanin. When bean were consumed both prior to and during DSS cycle, the mice experienced both disease attention and aggravation. However, when bean consumption was limited to prior to DSS induction only, mice had reduced colitis upon later DSS induction. Overall, findings suggest that the effects of bean may differ depending on the timing of consumption. / Agriculture and Agri-Food of Canada, Ontario Ministry of Agriculture and Rural Affairs
15

Evaluation of Post Harvest Technologies for Improving Strawberry Fruit Quality

Misran, Azizah 17 May 2013 (has links)
Fragaria ananassa, generally known as strawberry is a nutritious fruit that is rich in polyphenols and widely consumed as part of a healthy diet. Anthocyanins have been found to be the main group of phenolic components present in strawberry with pelargonidin-3-glucoside as the major component in all strawberry cultivars studied. The main volatile component has been identified as caryophyllene oxide, a sesquiterpene compound that was present abundantly in all cultivars. The effect of preharvest spray applications of a formulation containing hexanal which is known to enhance membrane preservation, was evaluated using two strawberry cultivars, ‘Jewel’ and ‘Mira’. Our results suggest that preharvest spray application of hexanal formulation results in biochemical changes that alter the profile of phenolic compounds and the volatiles of the fruit. An osmotic infusion treatment was implemented to generate an intermediate moisture food product with high quality and enhanced storage life that can be potentially used in processed food. Infusing strawberry with other functional ingredients such as fructoligosaccharides, lecithin, and ascorbic acid showed that the infused strawberry produced by this technique was structurally and organoleptically similar to fresh strawberry, and visually similar to the intial fruits. Drying of infused fruits could extend their shelf life up to several months, while providing fruit products with superior nutritional qualities. Subjecting strawberry fruit extract to a simulated in vitro digestion of strawberry greatly affected the polyphenol composition and concentrations during different stages of digestion. The concentrations of most polyphenols increased during gastric digestion suggesting that the acidic environment of the stomach may help to release polyphenols that are bound to the strawberry matrix. Following incubation of the IN and the OUT fractions with colonic bacteria, the presence of urolithin B glucunoride in the IN fraction and the increase of ellagic acid deoxyhexoside in both the IN and OUT fractions after fermentation process, suggest that the polyphenols are catabolized into simple phenolic compounds in the colon. The remaining polyphenols as well as the catabolites in the gut, could potentially have a beneficial effect in enhancing colonial health. / Ministry of Higher Education Malaysia, Universiti Putra Malaysia
16

Alkylresorcinols in cereal grains : occurrence, absorption, and possible use as biomarkers of whole grain wheat and rye intake /

Ross, Alastair Benjamin, January 2003 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv., 2003. / Härtill 8 uppsatser.
17

Alkylresorcinols as biomarkers of whole grain wheat and rye intake /

Landberg, Rikard, January 2009 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet. / Härtill 6 uppsatser.
18

Avaliação das propriedades de uma cerveja artesanal tipo pilsen suplementada com polpa de maracujá / Evaluation of the properties of a artisanal pilsen beer supplemented with pulp of passion fruit

Sorbo, Amanda Cristina Alfredo Contrucci [UNESP] 23 August 2017 (has links)
Submitted by AMANDA CRISTINA ALFREDO CONTRUCCI SORBO DA SILVA null (amandasorbo@gmail.com) on 2017-10-18T17:23:44Z No. of bitstreams: 1 Dissertação - Amanda 18-10.pdf: 1227056 bytes, checksum: 3218b89243028421630227dd2ead9bf7 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-10-23T18:10:44Z (GMT) No. of bitstreams: 1 sorbo_acac_me_bot.pdf: 1227056 bytes, checksum: 3218b89243028421630227dd2ead9bf7 (MD5) / Made available in DSpace on 2017-10-23T18:10:44Z (GMT). No. of bitstreams: 1 sorbo_acac_me_bot.pdf: 1227056 bytes, checksum: 3218b89243028421630227dd2ead9bf7 (MD5) Previous issue date: 2017-08-23 / A cerveja é uma das bebidas mais consumidas no mundo. Seu consumo moderado é capaz de promover benefícios ao organismo pela presença de compostos bioativos, incluindo vitaminas do complexo B e minerais. O mercado de bebidas, sempre em busca de produtos exclusivos, favoreceu o surgimento do ramo de cervejas artesanais. Além disso, pela possibilidade de acesso às receitas, é concebível associar à bebida, certas características organolépticas e nutracêuticas de interesse funcional. Neste sentido, este trabalho teve como objetivo identificar possível associação dos efeitos funcionais da cerveja Pilsen ao potencial antioxidativo da polpa de maracujá. O delineamento experimental foi inteiramente casualizado, sendo o controle, o Tratamento 1 (T1) representado pela cerveja Pilsen, produzida artesanalmente. Nos demais tratamentos, as cervejas foram suplementadas com polpa de maracujá em três concentrações, durante o processo de refermentação (priming). Para o tratamento 2 (T2), a cerveja foi suplementada com polpa integral de maracujá (120 mL); Para os tratamentos T3 e T4, a suplementação com polpa foi da ordem de 50 e 25 % da polpa diluída, respectivamente. Todos os tratamentos foram repetidos três vezes, em brassagens independentes. Os processos de mosturação e fermentação da cerveja seguiram os procedimentos padrões de brassagem e maturação típicas de cervejas lager, com temperatura controlada entre 11 e 13 °C. Após a produção das cervejas, realizou-se análise sensorial, por meio de teste de aceitação e demais análises físico-químicas. A adição de polpa de maracujá como adjunto no processamento da cerveja mostrou-se alternativa viável demonstrada pelos resultados satisfatórios na avaliação sensorial, além de apresentar características físico-químicas de cerveja artesanal frutada. O tratamento T2 apresentou o menor teor de açúcar e maiores teores de compostos fenólicos e capacidade antioxidante. A suplementação da cerveja com diferentes porcentagem de polpa de maracujá não interferiu na aceitabilidade da bebida pelos provadores quando comparada com a cerveja Pilsen tradicional. Entretanto, os avaliadores do sexo masculino tiveram preferência pelo tratamento T2 para atributos de sabor e odor. / Beer is one of the most consumed alcoholic drinks in the world and the moderate intake is able to promote benefits to the organism by the presence of bioactive compounds. The beverage market looks for exclusive products and it favors artisanal beer sector. It is possible associate some organoleptic and nutraceutical characteristics of functional interest at drink. The objective of this study was to identify a possible association of the functional effects of Pilsen beer with the antioxidant potential of passion fruit. The experimental design was random; the control (T1) treatment was Pilsen beer without addition of passion fruit pulp. The others treatments (T2, T3 e T4) containing passion fruit pulp added in 3 concentrations (100% of the whole pulp corresponding to 120ml, 50% in proportion 1 pulp: 1 water, and 25% in proportion 1 pulp: 3 water), with 3 replicates. It was used standard brewing procedures of Pilsen beer. Sensory analysis was accounted by means of acceptance test and physicochemical analysis. The supplemented with passion fruit pulp beers had higher values of biochemical parameters. The treatment T2 had the lowest sugar content and higher contents of phenolic compounds and antioxidant capacity. The supplementation of beer with different percentage of passion fruit pulp did not interfere with the acceptability of the drink by the tasters when compared to the traditional Pilsen beer. However, male evaluators preferred treatment T2 for taste and smell attributes. The addition of passion fruit pulp proved to be a viable alternative demonstrated by the satisfactory results in the sensorial evaluation.
19

Caracterização fenólica e capacidade antioxidante de vinhos tintos do Hemisfério Sul

SILVA, Tacila Mendes da 22 June 2015 (has links)
Submitted by Isaac Francisco de Souza Dias (isaac.souzadias@ufpe.br) on 2016-03-04T18:48:09Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação final Tacila.pdf: 1238681 bytes, checksum: 6cca34a1235332cde644aeb6e77a8651 (MD5) / Made available in DSpace on 2016-03-04T18:48:10Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação final Tacila.pdf: 1238681 bytes, checksum: 6cca34a1235332cde644aeb6e77a8651 (MD5) Previous issue date: 2015-06-22 / CAPES / A vitivinicultura, comumente praticada em países da Europa, foi repassada no período da colonização à novas regiões, cujas diversidades geográficas e climáticas proporcionam a uvas e vinhos concentrações variadas de compostos fenólicos, uma fonte de antioxidantes, capazes de redução e prevenção do risco de doenças. Este trabalho teve como objetivo verificar a existência de correlações entre composição fenólica e atividade antioxidante de vinhos tintos elaborados por quatro distintos países do hemisfério sul. A pesquisa foi constituída por dez amostras de vinhos tintos comerciais, a partir das variedades de uva, Cabernet Sauvignon (CS) e Syrah (SY), safra 2012, produzidos no Brasil (Vale do São Francisco (VSF) e do Rio Grande do Sul (RS)), no Chile, na Austrália e na África do Sul. Os vinhos foram avaliados por meio de análises, físico-químicas, espetrofotométricas e cromatográficas, com determinação e quantificação de compostos fenólicos, parâmetros cromáticos (intensidade de cor, tonalidade e % de vermelho, amarelo e azul) e capacidade antioxidante (% de inibição do DPPH*). As análises foram submetidas ao teste de variância (ANOVA), utilizando o teste de Duncan para comparação. Quanto as análises físico-quimicas clássicas, exceto o pH que apresentou valores elevados, todas as amostras estavam coerentes com os achados da literatura. Todos os vinhos estudados apresentaram elevada capacidade antioxidante (96,80- 95,01% (SY) e 97,47-94,0% (CS)) e valores elevados de polifenóis totais, com valores mínimo, 1421,5 e 1045,4 mg.L-1 e máximo, 1905,7 e 3052,72 mg.L-1 em equivalente de ácido gálico (EAG), exibidos por uvas do tipo SY e CS, respectivamente. Elevadas correlações foram verificadas entre a capacidade antioxidante e polifenóis totais em vinhos do Chile, Rio Grande do Sul e Vale do São Francisco, da uva Syrah, e da África, Chile e Vale do São Francisco, da Cabernet Sauvignon. O conteúdo de antocianina apresentou diferenças significativas entre todos os vinhos avaliados de ambos cultivares. Os resultados referentes à caracterização cromática foram elevados para todos os parâmetros, revelando os vinhos pesquisados como envelhecidos. Neste estudo, o isômero trans- resveratrol não foi detectado em nenhuma das amostras avaliadas, contudo, a concentração do isômero cis- detectada variou de 0, 00 a 0,32 mg.L-1 nos vinhos CS e 0,00 a 0,29 nos vinhos SY. Dentre os ácidos pesquisados, o gálico apresentou superioridade, porém foi não encontrada correlação do mesmo com a capacidade antioxidante. Estes resultados apontam para a influência do tipo de fenólico, presente nas variedades de uvas, sobre a capacidade antioxidante destes vinhos. / The wine industry, commonly practiced in European countries, was passed in the period of colonization of new regions, whose geographical and climatic diversity provide the grapes and wines varying concentrations of phenolic compounds, a source of antioxidants, able to reduce and prevent the risk of disease . This study aimed to verify the existence of correlations between phenolic composition and antioxidant activity of red wines produced by four different countries of the South. The survey consisted of ten samples of commercial red wines from the grape varieties Cabernet Sauvignon (CS) and Syrah (SY), vintage 2012, produced in Brazil (Vale do São Francisco (VSF) and Rio Grande do Sul (RS)), Chile, Australia and South Africa. The wines were evaluated through analysis, physicochemical, espetrofotométricas and chromatographic with determination and quantification of phenolic compounds, chromatic parameters (color intensity, tone and % red, yellow and blue) and antioxidant capacity (% inhibition of DPPH *). The analyzes were subjected to analysis of variance (ANOVA) using Duncan's test for comparison. As the classical physical-chemical analysis, except that showed high pH values, all samples were consistent with the literature findings. All studied wines showed high antioxidant capacity (96,80- 95,01% (SY) and from 97.47 to 94.0% (CS)) and high values of total polyphenols, with minimum, 1421.5 and 1045, 4 mg l-1 and maximum of 1905.7 and 3052.72 mg L-1 equivalent of gallic acid (EAG), displayed by grape type SY and CS respectively. High correlations were found between the antioxidant capacity and total polyphenols in wines from Chile, Rio Grande do Sul and São Francisco Valley, the Syrah grape, and Africa, Chile and Vale do São Francisco, the Cabernet Sauvignon. The anthocyanin content showed significant differences among all evaluated wines of both cultivars. The results of the chromatic characterization were high for all parameters, revealing the wine researched as aged. In this study, the isomer trans-resveratrol was not detected in any of the samples, however, the concentration of the cis isomer detected ranged from 0 00 to 0.32 mg.L-1 to CS wines and 0.00 to 0, 29 in SY wines. Among the surveyed acid, gallic presented superiority, but no correlation was found with the same antioxidant capacity. These results point to the influence of the type of phenolic, present in grape varieties on the antioxidant capacity of these wines.
20

Avaliação da composição e da capacidade antioxidante "in vivo" e "in vitro"de antocianinas da casca de jabuticaba (Myrciaria jaboticaba (Vell.) Berg) liofilizada em ratos Wistar / Evaluation of composition and antioxidant capacity in vivo and in vitro anthocyanins in freeze-dried jaboticaba peel (Myrciaria jaboticaba (Vell.) Berg) in rats

Leite, Alice Vieira 16 August 2018 (has links)
Orientador: Mário Roberto Maróstica Júnior / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-16T13:28:38Z (GMT). No. of bitstreams: 1 Leite_AliceVieira_M.pdf: 971111 bytes, checksum: 075888bf78f40ee6ae18cdf0e3fb131a (MD5) Previous issue date: 2010 / Resumo: O objetivo do presente estudo foi avaliar a produção de casca de jabuticaba em pó, sua composição de antocianinas e efeito antioxidante em animais de laboratório. Muitas frutas tropicais são ricas em antocianinas e existem poucos dados disponíveis sobre a caracterização e quantificação destas antocianinas. A identificação e quantificação de antocianinas de casca de jabuticaba liofilizada foram realizadas por HPLC-PDA e HPLC-ESI-MS/MS e revelaram a presença de dois compostos, delfinidina-3-glicosídeo e cianidina-3- glicosídeo (635,3 e 1964 mg/100 de peso seco), respectivamente. Para as análises do potencial antioxidante foram utilizados os ensaios de ORAC, DPPH e ABTS. Para estes ensaios foram encontrados os seguintes valores, respectivamente, 25514,25±3037,24 YMTEAC.g-1, 45,38 Yg.ml-1, 9457,74±54,29 YMTEAC.g-1. Foram quantificados também os fenólicos totais por Folin-Ciocalteau, e encontrado 556,28±20,37 gGAEb.kg-1 .Neste estudo, a casca de jabuticaba liofilizada mostrou uma grande capacidade antioxidante comprovada por todos os métodos antioxidantes analisados, pela quantidade de compostos fenólicos encontrada e principalmente pela concentração de cianidina-3-glicosídeo e delfinidina-3- glicosídeo. Diante dos dados descritos acima, o efeito antioxidante da ingestão de pó casca de jabuticaba liofilizada no plasma de ratos foi investigado em dois experimentos. No primeiro foi realizado um teste de cinética de absorção, no qual trinta e cinco ratos machos, divididos em 5 grupos, receberam por gavagem 7 mg de antocianinas/ 100 g de peso. A coleta de sangue foi realizada nos tempos 0, 30, 60 e 120 minutos. O potencial antioxidante foi quantificado no plasma por ORAC e TEAC. Neste experimento não ocorreu diferença significativa no potencial antioxidante plasmático quando comparados os diversos tempos. No segundo experimento, 40 ratos machos foram divididos em 4 grupos que consumiram, respectivamente, 0, 1, 2 e 4% de pó de casca de jabuticaba liofilizada acrescido a dieta. Foi observado um aumento no potencial antioxidante plasmático (1.7 vezes pelo método de TEAC e 1.3 vezes por ORAC), porém a concentração de 4% não apresentou efeito antioxidante. A partir dos resultados do potencial antioxidante in vivo, e diante do fato de que a ingestão de uma dieta rica em antioxidantes e com pouca quantidade de gorduras pode reduzir o risco de obesidade e resistência à insulina, investigou-se o efeito da casca de jabuticaba liofilizada sobre as concentrações plasmáticas de glicose, frações lipídicas, aspartato aminotransferase e alanina aminotrasferase em ratos Wistar machos adultos. Os animais foram distribuídos nos seguintes grupos: G0, o grupo controle e G1, G2 e G4, os grupos que receberam 1, 2 e 4%, respectivamente, do pó de casca de jabuticaba liofilizada adicionado à dieta AIN-93M. A suplementação reduziu as concentrações de glicose nos grupos G1 e G2, porém no grupo G3 esse efeito não foi encontrado. O colesterol total sofreu redução para os animais tratados com 1% de cascas de jabuticabas em relação ao grupo controle, mas os animais tratados com 2 e 4% de cascas de jabuticabas sofreram aumento no colesterol total e da fração LDL-colesterol, porém, o valor para colesterol total apresenta-se dentro da faixa normal para ratos Wistar. Os triacilgliceróis e a fração HDL-colesterol não sofreram alterações significativas. Os resultados indicam um possível benefício da suplementação da casca de jabuticaba na redução da glicemia plasmática, dos níveis de LDL e colesterol total e a possível existência de uma dose recomendada / Abstract: The objective of this study was to evaluate the antioxidant effects of anthocyanin and the antioxidant effects of peel jabuticaba powder in laboratory animals. Many tropical fruits are rich in anthocyanins, but there are few data available on the characterization and quantification of these anthocyanins. The identification and quantification of anthocyanins from bark jabuticaba was performed by HPLC-PDA and LC-ESI-MS/MS Q-TOF. The analysis revealed the presence of two compounds, delphinidin-3-glucoside and cyanidin-3-glucoside (635, 3 and 1964 mg/100 dry weight, respectively). ORAC, DPPH and ABTS methods were used for antioxidant analysis and the results were, 25514,24±3037,24 µMTEAC.g-1, 45.38 Yg.ml-1, 9457,74±54,29 µMTEAC.g-1, respectively. The total phenolics (Folin-Ciocalteau method) revealed that the jabuticaba powder contained 556,28±20,37 gGAEb.kg-1. In this study, freezedried peel jabuticaba showed great antioxidant proven by all methods antioxidants tested. The effects of the ingestion of jabuticaba peel in the antioxidant capacity of plasma of rats was investigated in two 'in vivo¿ experiments. In the first test, the absorption kinetics were evaluated. The male rats were divided into 5 groups received, by gavage, 7 mg anthocyanins / 100 g of body weight. Blood collection was performed at 0, 30, 60 and 120 minutes. The antioxidant potential was quantified in plasma by ORAC and TEAC. In this experiment there was no significant difference in plasma antioxidant potential when comparing the different times. In the second experiment, 40 rats were divided into 4 groups that consumed, respectively, 0, 1, 2 and 4% powdered peel jabuticaba lyophilized plus diet. We observed an increase in plasma antioxidant potential (1.7 times by the method of TEAC and ORAC by 1.3 4 times), but the concentration of 4% had no antioxidant effect. We investigated the effect of freeze-dried peel jabuticaba on plasma glucose, lipid fractions, aminotransferase and aspartate aminotransferase alanian in adult male Wistar rats. The animals assigned to groups G0, the control group, G1, G2 and G4 groups receiving 1, 2 and 4%, respectively, of freeze-dried peel jabuticaba added to the AIN-93M diet. Supplementation reduced the concentration of glucose in G1 and G2, but in G4 this effect was not found. Total cholesterol was reduced in animals treated with 1% bark jabuticabas in the control group, but animals treated with 2 and 4% experienced an increase in total cholesterol and LDL cholesterol, but the value for cholesterol total amount is within the normal range for rats. Triglycerides and HDL-cholesterol did not change significantly. The results indicate the possible benefit of supplementing with bark jabuticaba in reducing plasma glucose, LDL cholesterol and total cholesterol and the possible existence of a dose / Mestrado / Nutrição Experimental e Aplicada à Tecnologia de Alimentos / Mestre em Alimentos e Nutrição

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