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Made available in DSpace on 2018-08-02T00:16:23Z (GMT). No. of bitstreams: 1 tese_5189_dissertacao copia pdf 16-06-11.pdf: 1399769 bytes, checksum: 0958cfc2a47f37e3c2fa855d50d600f9 (MD5) Previous issue date: 2011-02-28 / RESUMO Esse estudo objetivou investigar, em regime de casa de vegetação, o desempenho fisiológico de duas cultivares (FB300 e FB200) do maracujazeiro Passiflora edulis Sims., submetidas à deficiência hídrica e posterior recuperação. Os parâmetros analizados foram: potêncial hídrico (ψw), fluorescência transiente (teste JIP) e modulada da clorofila a, teor de clorofila, atividade da catalase , peroxidase e determinação da peroxidação lípidica pelo conteúdo de MDA (malondialdeído). Sessenta dias após a germinação, o déficit hídrico foi iniciado pela supressão total da água por 11 dias e seguido por 6 dias de reidratação. As duas cultivares apresentaram um comportamento semelhante de redução do ψw com o avanço da supressão hídrica e recuperação com a reidratação. Entretanto, a cultivar FB200 mostrou-se mais susceptível ao déficit hídrico comprovado por uma maior queda de seus valores em todos os parâmetros analisados e por um maior aumento dos níveis de peroxidação lipídica. FB300 apresentou uma maior plasticidade fisiológica para tolerar a imposição da supressão hídrica, confirmada pelo menor declínio dos valores na maioria dos parâmetros analisados e pelo menor tempo necessário para sua recuperação ao nível do controle.

Platelet activating factor (PAF) is a unique signaling phospholipid that has many biologic properties in addition to platelet activation. PAF roles in reproduction involve ovulation, fertilization, embryo development, implantation and parturition. It may also serve as a biomarker for normal sperm function. The presence of PAF receptor on the spermatozoa of 10 stallions was investigated by immunofluorescence microscopy. Statistical analysis revealed that the fluorescence intensity, FI (Mean+/-SEM), in the post- acrosomal region (FI= 2.60+/-0.15) was significantly higher (P< 0.01) than that in any other region of stallion spermatozoa. The effect of synthetic PAF on stallion spermatozoal motility, capacitation, and the acrosome reaction (AR) were evaluated. Treatment of 10 stallion semen samples with 10 â 4 to 10 â 13 M PAF resulted in statistically significant differences in motility and capacitation (r2 = 0.81 and 0.83 respectively). The concentration of PAF, incubation time and their interaction were highly significant (P< 0.01) for their effect on motility. Concentrations of PAF ranging from 10-9 to10-11 M were able to induce capacitation. Following capacitation in vitro with PAF, and induction of the acrosomal reaction by progesterone, transmission electron microscopy (TEM) was conducted on the spermatozoa of 3 stallions, to detect the true AR. Differences in PAF concentrations were highly significant as indicated by R-square (for intact: 97.2, reacted: 89.8, and for vesiculated: 98.1). Treating spermatozoa from 3 stallions with the PAF antagonist FR-49175 inhibited calcium release and fluorescence intensity with a median inhibitory concentration (IC50) of 10-7.5 M (r2=0.82, P<0.01) and 10-8 M (r2=0.92, P<0.01) respectively, suggesting a receptor mediated process for the mechanism of action of PAF. Although the exact mechanisms of PAF action on equine spermatozoa remain unclear, it is widely reported that PAF acts by a receptor-mediated mechanism and that the PAF receptor is a member of the family of G-protein coupled receptors with phospholipase C as the effector. Since the limited success in equine ART (e.g. IVF) is in part due to lack of efficient treatment of stallion spermatozoa for capacitation, PAF may be useful to help capacitate stallion spermatozoa. Without proper capacitation, spermatozoa are unable to initiate the acrosome reaction which is a prerequisite for fertilization. / Ph. D.

Cette étude examine les effets bénéfiques des marcs de raisins obtenus après vinification de différents cépages caractéristiques de la Vallée du Rhône, de leurs compositions phénoliques à leurs effets in vivo. Les raisins et leurs marcs respectifs des cépages Grenache (provenant de deux endroits différents [GRE1] et [GRE2]), Syrah (provenant de deux endroits différents [SYR1] et [SYR2]), Carignan (CAR), Mourvèdre (MOU), Counoise (COU) et Alicante (ALI) ont été étudiés. La comparaison des extraits de raisins et de leurs marcs respectifs montre que les marcs représentent une source importante d’antioxydants phénoliques malgré le processus de vinification. Les pépins et pellicules de marcs renferment des quantités appréciables de flavan-3-ols et anthocyanes. La distribution qualitative et quantitative des polyphenols dans les marcs de raisin présentent des différences significatives au travers des variétés et millésimes allant de 15% à 70% de polyphénols extraits. Les pépins de Grenache (GRE1), Syrah (SYR1) et les pellicules de Syrah (SYR1), Carignan et Alicante sont les fractions les plus intéressantes dues a la présence d’importantes quantités de flavan-3-ols (monomères, dimères et trimère) jusqu’à 8.7 mg/g MS et d’anthocyanes (glycosylées, acétylées et coumaroylées jusqu’à 17.40 mg/g MS, 1.57 mg/g MS et 2.38 mg/g MS respectivement). L’analyse des extraits aqueux (EAQ) et hydro-alcoolique 70% (EA70) indique que les pépins de Carignan et Syrah (SYR1) et les pellicules de Carignan et d’Alicante contiennent les plus fort taux en composés phénoliques et activités antioxydantes. L’efficacité in vivo sur l’hypertension de certains extraits a été évaluée utilisant un modèle de rat SHR. Les résultats des expériences in vivo démontrent que certains extraits administrés seuls ou en association avec le vérapamil possèdent un effet anti-hypertenseur. Cette capacité a été mise en évidence une fois que les extraits de pépins de marcs de GRE1 (EA70) et SYR1 (EA70) et de pellicules de marcs d’ALI (EA70) ont été administrés seuls ou lorsque les extraits de pépins de marcs GRE1 (EA70) et SYR1 (EAQ) et les pellicules de marcs d’ALI (EA70) et SYR2 (EAQ) ont été administrés en association avec le vérapamil. Cette étude met en évidence la biodisponibilité des extraits de pépins et de pellicules de marcs des rats SHR incluant à la fois le métabolisme de phase II et de la microflore intestinale. Les extraits de marcs administrés seuls et en association au vérapamil sont absorbés en tant que métabolites de phase II dérivant du métabolisme des monomères de flavan-3-ols. La détection de métabolites microbiens dérivés de flavan-3-ols, d’hydroxyphényl-γ-valérolactones sous leurs formes glucuronidés et sulfatés confirme l'absorption des métabolites dérivés des flavan-3-ols monomères et polymères et des conjugaisons supplémentaires dans le foie. De nombreux métabolites issus de la dégradation microbienne des hydroxyvalerolactones ont également été détectés. L’excrétion urinaire de ces métabolites représente une plus grande proportion de polyphénols ingérés comparé à ceux issus de métabolisme de phase II des monomères de flavan-3-ols, indiquant un rôle important des bactéries intestinales dans le métabolisme des molécules hautement polymérisées. Ces métabolites peuvent avoir exercé leurs effets biologiques lors de leur passage dans la circulation sanguine. Cette étude constitue une première étape de valorisation de marcs de raisins après vinification, en tant qu’activateur de vérapamil, un médicament couramment utilisé contre l’hypertension. Des quantités suffisantes de composés phénoliques subsistent dans les marcs, en particulier en terme de flavan-3-ols et d’anthocyanes, pour exercer des effets antihypertenseurs. En effet, selon le type et la composition des extraits, il est possible de moduler les effets antihypertenseurs en amplifiant ou en diminuant l’absorption des polyphénols et/ou du vérapamil. / This study investigated the beneficial potential effects of grape pomaces obtained after winemaking of different Mediterranean grape varieties from crude materials to their in vivo effectiveness. Grapes and their respective grape pomaces from six different V. vinifera L. cultivar were studied namely Grenache (from two different locations [GRE1 and GRE2]), Syrah (from two different locations [SYR1 and SYR2]), Carignan (CAR), Mourvèdre (MOU), Counoise (COU) and Alicante (ALI) grape varieties from the Rhône Valley. The comparison of several wine industry by-products with their respective grapes provided evidence that pomace remaining at the end of the winemaking process can be very rich sources of antioxidants. The quantitative and qualitative distribution of polyphenols by HPLC-PDA-Fluo-MS in grape pomaces showed significant differences through varieties and vintages varying from 15% to 70% of polyphenols extracted. Seeds from Grenache (GRE1), Syrah (SYR1) and skins from Syrah (SYR1), Carignan and Alicante were of particular interest because of their higher polyphenol contents in terms of flavan-3-ols (monomers, dimers and trimers) up to 8.7 mg/g DW and anthocyanins (glycosides, acetylated and coumaroylated derivatives up to 17.40, 1.57 and 2.38 mg/g DW, respectively). The investigation of aqueous and hydro-alcoholic 70% extracts of seeds from Carignan and Syrah (SYR1) and skins from Carignan and Alicante was carried out as they contained high levels of total phenols and antioxidant activity. Several extracts, were tested in order to evaluate their in vivo biological effects on hypertension using a spontaneously hypertensive rat (SHR) model. A series of different grape pomace extracts were tested in association with verapamil. All in vivo experiments demonstrated that some grape pomace extracts administrated with or without co-ingestion with verapamil possessed an anti-hypertensive activity. This was evident with GRE1 (EA70) seed pomace extract, SYR1 (EA70) seed pomace extract, ALI (EA70) skin pomace extract administrated alone and with GRE1 (EA70) seed pomace extract, SYR1 (EAQ) seed pomace extract, ALI (EA70) skin pomace extract and SYR2 (EAQ) skin pomace extract administrated in association with verapamil. Grape pomace extracts with or without co-ingestion with verapamil were absorb as phase II metabolites mainly including glucuronide, O-methyl glucuronide, sulfate, and O-methyl sulfate derivatives of (epi)catechin which arise from the metabolism of monomeric flavan-3-ols. The detection by HPLC-PDA-Fluo-MSn and GC-MS of microbial-derived metabolites of flavan-3-ols, hydroxyphenyl-γ-valerolactones in their glucuronide and sulfate forms confirmed the absorption of metabolites derived from both monomeric and polymeric flavan-3-ols from grape pomace extracts and subsequent post-absorption conjugation. Numerous metabolites derived from further microbial degradation of hydroxyvalerolactones were also detected. The urinary excretion of these metabolites accounted for a larger proportion of the total polyphenol ingested than phase II metabolites of monomeric flavan-3-ols, indicating the important role of intestinal bacteria in the metabolism of polymerized procyanidins. All these metabolites may have exerted biological effects during the period in which they circulated in the bloodstream. This study constitutes the first step of assessing grape pomace as an enhancer of the verapamil, an anti-hypertensive drug. Substantial levels of polyphenols, especially flavan-3-ols, procyanidins and anthocyanins, remain in pomace after the winemaking process in quantities sufficient to exert anti-hypertensive effects. In addition, according to the extract used and its composition, it is feasible to modulate anti-hypertensive effects by amplifying or decreasing polyphenols and/or verapamil absorption.

La contraction du muscle squelettique est initiée par une libération de Ca2+ du réticulum sarcoplasmique (RS) en réponse à une dépolarisation du sarcolemme. Celle-ci induit un changement de conformation du récepteur des dihydropyridines (DHPR) localisé dans les tubules T entraînant l'ouverture du récepteur de la ryanodine de type 1 (RyR1), canal calcique du RS, et la libération du Ca2+ accumulé dans le RS. Au repos, RyR1 serait maintenu fermé par une action répressive du DHPR. Néanmoins, un efflux de Ca2+ continu se développe à travers la membrane du RS, constamment compensé par l'activité des pompes Ca2+-ATPases. Des études suggèrent que cet efflux pourrait être impliqué dans la perturbation de l'homéostasie calcique dans une des pathologies musculaires des plus fréquentes et sévères, la myopathie de Duchenne. Le travail présenté vise à caractériser l'efflux de Ca2+ du RS dans les fibres musculaires squelettiques de souris normales et mdx, modèle murin de la myopathie de Duchenne, en couplant la technique de potentiel imposé et la mesure fluorimétrique du Ca2+ intracellulaire. La mise au point d'une mesure directe des variations de Ca2+ du RS à l'aide du Fluo-5N a permis de révéler dans les fibres mdx une fuite calcique du RS exacerbée. Cette approche a permis de démontrer que l'efflux calcique du RS dans la fibre musculaire squelettique au repos n'est pas un phénomène incontrôlé à travers RyR1 mais un efflux étroitement contrôlé par le DHPR. Enfin, on s'est intéressée à l'efflux de Ca2+ du RS lors d'une stimulation musculaire prolongée. Nos résultats montrent que le déclin du signal calcique cytosolique dans ces conditions résulterait de la déplétion calcique du RS / Contraction of skeletal muscle is triggered by the release of Ca2+ from the sarcoplasmic reticulum (SR) in response to depolarization of the sarcolemma. Depolarization elicits a conformational change of the dihydropyridine receptor (DHPR) localized in the tubular membrane that controls the opening of the type 1 ryanodine receptor (RyR1), the SR Ca2+ release channel. At rest, RyR1s are kept in a closed state imposed by the repressive action of DHPRs. Yet, a resting Ca2+ efflux occurs across the SR membrane, constantly balanced by the pumping activity of SR Ca2+-ATPases. Several studies suggest that this SR Ca2+ efflux, considered as purely passive, may contribute to the alteration of Ca2+ homeostasis in one of the most common and severe skeletal muscle disease, namely the Duchenne Muscular Dystrophy. The present work aims at characterizing the SR Ca2+ efflux in skeletal muscle fiber from normal and mdx mice, the murine model of Duchenne Muscular Dystrophy, by combining voltage-clamp and intracellular Ca2+ measurements. The development of a methodology allowing direct monitoring of Ca2+ changes in the SR using the Fluo-5N led us to reveal an elevated SR Ca2+ leak in mdx fibers, which may contribute to the alteration of Ca2+ homeostasis. Still using this approach, we demonstrate that the resting SR Ca2+ efflux in normal skeletal muscle fiber is not, an uncontrolled process through RyR1 but is tightly controlled by DHPR. Finally, we investigates the SR Ca2+ efflux during long-lasting stimulation. Our data indicate that the decline of SR Ca2+ release in these conditions results from SR Ca2+depletion and does not involve voltage-dependent inactivation of SR Ca2+ release

La connaissance de la composition phénolique du Cabernet-Sauvignon (CS) et du Merlot (M) dans la région vitivinicole du bordelais a un intérêt majeur pour définir la structure et la qualité tannique (astringence et amertume) des raisins et des vins. La composition en tanins et anthocyanes de raisins et de vins issus du Cabernet Sauvignon et du Merlot ainsi que leur perception tannique ont été recherchées. L’étude raisins a été réalisée pour cinq parcelles de la région bordelaise (Pauillac, Margaux, Saint Emilion (1), Saint Emilion (2) Côtes de Bourg) pour trois millésimes consécutifs : 2006, 2007 et 2008 et différents types de sol : Limoneux, Sableux, Limono-Sableux 1, Limono-Sableux 2, Limon argilo-sableux pour le M et Limono-argileux, Sablo-limoneux 1, Limono-sableux, Sablo-limoneux 2 et Limoneux pour le CS. Les monomères [(+)-catéchine (C), (-)-épicatéchine (EC), (-)-épicatéchine-O-gallate] et les oligomères (dimères: B1, B2, B3, B4 et trimère Cat-Cat-Epi) des procyanidines, ont été identifiées et quantifiées pour les extraits de raisins (pépins et pellicules) et pour les vins par CHLP-UV-Fluo. Le pourcentage de galloylation (%G), le pourcentage de prodelphinidines (%P) ainsi que le degré moyen de polymérisation (DPm) des tanins oligomères des raisins et des tannins de vin ont été déterminés par CHLP-UV-SM. L’intensité d’astringence et d’amertume des tanins oligomères des raisins (pépins et pellicules) et des vins ont été estimées par analyse sensorielle. Les anthocyanes monoglucosides [cyanidine-3-O-glucoside (Cy), delphinidine-3-O-glucoside (Dp), paeonidine-3-O-glucoside (Pn), malvidine-3-O-glucoside (Mv), petunidine-3-O-glucoside (Pt)] et les anthocyanes acétylées (paeonidine-3-O-glucoside, malvidine-3-O-glucoside) et coumaroylées (paeonidine-3-O-glucoside, malvidine-3-O-glucoside) ont été identifiées et quantifiées par CLHP-UV-SM dans les extraits de pellicules et dans les vins. L’influence du sol, du millésime, et du cépage (pour les raisins et les vins) ont été explorés. Le millésime, dans les deux cas (raisins et vins), a un effet très significatif et domine celui du cépage (raisins et vins) et celui du sol (raisins) sur la plupart des variables étudiées. Selon le type de sol et le millésime, la qualité tannique des raisins est évaluée. Les pépins de CS issus du sol Limono-sableux présentent une grande variabilité au niveau du DPm (3,8 à 7,2) et au niveau du % G (19,0 à 51,3). Ceux-ci sont plus astringents et amers que les pépins issus des autres types de sols. Les pépins (CS) du millésime 2006 sont plus astringents et amers que ceux des autres millésimes, même s’ils sont caractérisés par des valeurs de DPm et % G deux fois moins élevées que ceux de 2007. Pour les sols Limono-sableux, les pellicules (CS) possèdent les valeurs moyennes de DPm (30,89) et de % G (5,07) les plus élevées et sont perçues comme les plus astringentes. Les pépins de M issus du sol Limono-sableux 1 et du sol Limoneux présentent des DPm maximums de 3,20 et 3,03 ; avec des intensités moyennes d’astringence et d’amertume les plus élevées pour le sol Limono-sableux 1. Pour les pépins de M, les intensités d’astringence sont du même ordre pour les 3 millésimes. Les pépins (M) de 2007 possèdent le % G le plus élevé (33,34) et sont perçus plus amers par rapport aux autres millésimes. Les pellicules de M des sols sableux sont plus astringentes avec une variation forte du % P (3,8 à 14,0). Pour le M, les pellicules issues du sol Limoneux sont moins astringentes et se caractérisent par un DPm moins élevé (10,42) par rapport aux autres sols. Pour les pépins, le CS présente un DPm (4,15) et un % G (26,12) plus élevés que celui du M (2,74 et 21,22 %). Pour les pellicules, le CS se caractérise par un DPm (22,85), un % G (3,24 %) et un % P (14,99 %) plus élevés que ceux de M (DPm = 19,42, % G = 1,31 %, % P= 5,54). Pour les trois millésimes étudiés, le cépage n’a influencé ni l'amertume ni l'astringence pour les pépins et les pellicules. Les différences significatives et consécutives sur la composition en anthocyanes entre CS et M pour les trois millésimes portent sur : la Cy, la Pt, la Pn, la Mv et les anthocyanes acétylées et coumaroylées. Les teneurs en anthocyanes acétylées sont deux fois plus élevées pour le CS (6,99 mg/g), alors que le M présente des teneurs en anthocyanes coumaroylées (3,31 mg/g) plus élevées que celles du CS (1,99 mg/g). L’étude de la qualité tannique sur vins, a été réalisée pour 24 millésimes issus de CS et 7 millésimes issus de M. Les teneurs en composés phénoliques, en anthocyanes, en tanins totaux, en monomères des tanins (C+EC), la teinte, l’IC’ (intensité colorante), le % G, le % P et le DPm ainsi que l’intensité de l’astringence apparaissent comme des données pertinentes pour différencier les vins en fonction du millésime. Des corrélations entre l’âge des vins et : le DPm, la teinte, l’astringence, les teneurs en composés phénoliques totaux, en monomères de tanins (C+EC) et en tanins totaux ont pu être obtenues. La caractérisation qualitative des tanins et des vins est établie par corrélation entre l’astringence et le DPm (R2 = 0,509, p = 0,051, CS ; R2 = 0,780, p = 0,000, M). De plus, le DPm apparaît être un marqueur du millésime (R2 = 0,796, p = 0,000 ; CS et R2 = 0,946, p = 0,000 ; M). Nous proposons une échelle reliant le DPm des vins en fonction du millésime et de la perception tannique (astringence). Les vins issus du M sont caractérisés par une moindre richesse en composés phénoliques totaux, en tanins, en anthocyanes, en DPm, en % G, en % P ainsi que par une intensité d’astringence moins importante par rapport a ceux de CS. Le TAV (titre alcoométrique volumique, % vol) semble être positivement corrélé à l’amertume (r = 0,39, p < 0,05). / Cabernet-Sauvignon (CS) and Merlot (M) phenolic composition is of paramount importance to grapes and red wines structure and quality (astringency and bitterness) in Bordeaux winegrowing region. Tannins and anthocyanins composition as well as tannin perception have been studied for Cabernet-Sauvignon and Merlot grapes and wines. Grapes study was carried out with samples from five vineyards located in Bordeaux (Pauillac, Margaux, Saint Emilion (1), Saint Emilion (2)and Côtes de Bourg) for three consecutive vintages (2006, 2007 and 2008) and for different soil types (Silty, Sandy, Silty-sandy 1, Silty-sandy 2, Silty clay-sandy for M and Clay-loam, Sandy-silty 1, Silty-sandy, Sandy-silty 2 and Silty for CS). The proanthocyanidin monomers [(+)-catechin (C), (-)-epicatechin (EC), (-)-epicatechin-O-gallatte] and oligomers [dimers: B1, B2, B3, B4 and trimer Cat-Cat-Epi] from grape extracts (seed and skin) and wine were identified and quantified by HPLC-UV-Fluo. Percentage of galloylation (%G), percentage of prodelphinidins (%P) as well as mean degree of polymerization (mDP) of grape tannins oligomers and wine tannins were determined by HPLC-UV-MS. Sensory analysis concerning astringency and bitterness intensity of grape tannins oligomers (skins and seeds) and wines was also performed. The anthocyanic composition of glucosides [cyanidin-3-O-glucoside (Cy), delphinidin-3-O-glucoside (Dp), paeonidin-3-O-glucoside (Pn), malvidin-3-O-glucoside (Mv), petunidin-3-O-glucoside (Pt)] acetylated glucosides (paeonidin-3-O-glucoside, malvidin-3-O-glucoside]) and coumarylic glucosides (paeonidin-3-O-glucoside, malvidin-3-O-glucoside) of skins extracts and wines were analysed by HPLS-MS. Soil, vintage and grape variety influence on the above parameters are explored. The vintage in both cases (grapes and wines), has a significant effect and dominates that of grape variety (grape and wine) and soil (grape). Depending on soil type and vintage, tannins grapes quality is evaluated. CS seeds from Silty-sandy soil present a great variability on mDP (3.8 to 7.2) and on % G (19.0 to 51.3). The above seeds are more astringent and bitter than those from other soil types. The 2006 seeds (CS) are more astringent and bitter than these from the other vintages, even if they are characterized by G % and mDP values two times lower than these of 2007. Skins (CS) of Silty-sandy soils, have the highest mDP (30.89) and % G (5.07) average values and are perceived as more astringent. M seeds from Silty-sandy 1 and Silty soil have the maximum mDP values (3.20 and 3.03); Silty-sandy 1 M seeds present the highest astringency and bitterness intensities. For M seeds, astringency intensities present the same values for the 3 vintages. The 2007 seeds (M) have the highest % G (33.34) and are perceived bitter than those from the other vintages. M skins from Sandy soils are the most astringent with a strong variation on % P (3.8 to 14.0). M skins from Silty soils are less astringent and are characterized by lower mDP values (10.42) than these from other soils. In seeds, CS presents a mDP (4.15) and a % G (26.12) higher than M (2.74 and 21.22 %). CS skins are also characterized by higher mDP (22.85), % G (3.24 %) and % P (14.99 %) values than M (mDP = 19.42, % G = 1.31 % and %, P = 5.54 %). For all three vintages studied, the grape variety does not affect the astringency and bitterness intensity in both skin and seed tannins extracts. The consistent differences between CS and M for the three vintages on anthocyanin composition are on : Cy, Pt, Pn, Mv, acetylated and coumarylic anthocyanin levels. Acetylated anthocyanins values are two times highest for CS (6.99 mg/g), while M presents (3.31 mg/g) coumarylic anthocyanin levels higher than CS (1.99 mg/g). The study concerning wine tannin quality, was conducted for 24 vintages for CS and for 7 vintages for M. Total phenolic compounds, total anthocyanins, total tannins, tannin monomers (C+EC), hue, IC' (color intensity), % G, % P, mDP and astringency intensity differentiate wines according to vintage. The correlation between wine age and: mDP, hue, astringency, total phenolic compounds, tannin monomers (C+EC) and total tannin levels are obtained. The qualitative tannin and wine characterization is established by correlation between astringency and mDP (R 2 = 0.509, p = 0.051, CS; R2= 0.780, p = 0.000, M). In addition, the mDP appears to be vintage marker (R 2 = 0.796, p = 0.000; CS and R2 = 0.946, p = 0.000; M). Scale patterns between wine mDP and both ageing and tannin perception (astringency) are proposed. M wines are characterized by lower levels of total phenolic compounds, tannins, anthocyanins, mDP, % G, % P % levels as well as by lower astringency intensity than CS wines. Ethanol level seems to be positively correlated to bitterness (r = 0.39, p < 0.05).

A compreensão dos caminhos de desativação não radiativa em polímeros conjugados é fundamental para o uso desses materiais em dispositivos luminescentes, células fotovoltaicas e sensores. Nesta tese, os processos não radiativos em filmes automontados de polímero luminescente foram investigados via análise da supressão de intensidade de fotoluminescência, utilizando a técnica de fluorescência estacionária, e através da medida do tempo de vida do estado excitado com fluorescência resolvida no tempo em arranjo de contagem de fótons. A camada emissiva constituída por poli(p-fenileno vinileno) (PPV) obtido da conversão térmica do precursor poli(cloreto de xilideno tetraidrotiofeno) (PTHT) apresentou tempos de vida entre 150 e 250 ps, e fraca dependência com o comprimento de onda de detecção da emissão. Na presença de uma monocamada contendo azocorante Vermelho do Congo (CR) ou ftalocianina tetrassulfonada de níquel (NiTsPc) atuando como receptor de energia foi observada supressão da fluorescência e encurtamento do tempo de vida (50-100ps). À medida que se aumenta a distância entre as camadas de doador e receptor via interposição de bicamadas de espaçador, a dinâmica do sistema tende à dinâmica de decaimento do estado excitado do PPV na ausência de receptor. A dependência da eficiência com a distância 1/r2 ou 1/r3 apontam para transferência de energia ressonante (RET) típica da interação plano-plano ou plano-camada. Os processos não radiativos foram também estudados em função da diluição de segmentos PPV dispersos em matriz de polieletrólito poli(cloreto de dodecildimetilamônio) PDAC. A diluição dos segmentos conjugados aumenta a eficiência quântica de emissão, torna o mecanismo de desativação mais lento (500 ps) e diminui a dependência do tempo de vida com o comprimento de onda de detecção, devido à menor eficiência dos mecanismos de desativação não radiativa. Na presença de uma camada receptora, a eficiência de transferência de energia é maior para amostras com segmentos mais diluídos indicando que esse mecanismo compete com os processos internos à própria camada emissiva. O tempo de vida aumenta em filmes com mais baixo grau de conjugação e a dependência com o comprimento de onda de emissão é mais forte. Em resumo, a técnica de automontagem se mostrou adequada para obter filmes com propriedades fotofísicas controláveis no nível molecular, que puderam ser estudadas com espectroscopias de fluorescência. / Understanding the pathway of excitation in conjugated polymers is important for using these materials as active layer in devices, photovoltaic cells and sensors. In this thesis, non-radiative processes in layer-by-layer (LbL) films were investigated with measurements of fluorescence quenching in steady-state fluorescence spectroscopy and of the singlet excited state lifetime using time-resolved fluorescence spectroscopy in a single photon counting (SPC) apparatus. The emissive layer of poly(p-phenylene vinylene) (PPV) obtained via thermal conversion of the soluble precursor poly(xylylidene tetrahydrothiophenium) chloride (PTHT) showed lifetime 150-250 ps and weak dependence on the emission wavelength. In the presence of an acceptor layer of either Congo Red (CR) or nickel tetrasulfonated phthalocyanine (NiTsPc) the PL intensity was quenched and the lifetime was shorter (50 -100 ps). Upon increasing the distance between the energy donor (PPV) and acceptor layers by interposing bilayers of inert polyelectrolytes the dynamics tended to the PPV dynamics. The distance-dependence of the energy transfer efficiency (1/r2 or 1/r3) points to a resonant process (RET) with a plane-to-plane or plane-to-slab interaction. The non-radiative processes were also studied for varying dilutions of the PPV segments in a matrix of the polyelectrolyte poly(dodecyl methylamonium chloride) (PDAC). This dilution increased the quantum efficiency and led to longer lifetimes (500 ps) owing to a less effective non-radiative energy transfer. When an energy acceptor layer is present, energy transfer is more efficient for the most diluted systems, indicating that such transfer competes with internal processes in the emissive layer. The lifetime increased in films with low degree of conjugation, for which there was a stronger dependence on the emission wavelength. It is concluded that the LbL methodology was suitable to obtain photophysical film properties that could be controlled at the molecular level, and investigated with varied fluorescence spectroscopies.

A compreensão dos caminhos de desativação não radiativa em polímeros conjugados é fundamental para o uso desses materiais em dispositivos luminescentes, células fotovoltaicas e sensores. Nesta tese, os processos não radiativos em filmes automontados de polímero luminescente foram investigados via análise da supressão de intensidade de fotoluminescência, utilizando a técnica de fluorescência estacionária, e através da medida do tempo de vida do estado excitado com fluorescência resolvida no tempo em arranjo de contagem de fótons. A camada emissiva constituída por poli(p-fenileno vinileno) (PPV) obtido da conversão térmica do precursor poli(cloreto de xilideno tetraidrotiofeno) (PTHT) apresentou tempos de vida entre 150 e 250 ps, e fraca dependência com o comprimento de onda de detecção da emissão. Na presença de uma monocamada contendo azocorante Vermelho do Congo (CR) ou ftalocianina tetrassulfonada de níquel (NiTsPc) atuando como receptor de energia foi observada supressão da fluorescência e encurtamento do tempo de vida (50-100ps). À medida que se aumenta a distância entre as camadas de doador e receptor via interposição de bicamadas de espaçador, a dinâmica do sistema tende à dinâmica de decaimento do estado excitado do PPV na ausência de receptor. A dependência da eficiência com a distância 1/r2 ou 1/r3 apontam para transferência de energia ressonante (RET) típica da interação plano-plano ou plano-camada. Os processos não radiativos foram também estudados em função da diluição de segmentos PPV dispersos em matriz de polieletrólito poli(cloreto de dodecildimetilamônio) PDAC. A diluição dos segmentos conjugados aumenta a eficiência quântica de emissão, torna o mecanismo de desativação mais lento (500 ps) e diminui a dependência do tempo de vida com o comprimento de onda de detecção, devido à menor eficiência dos mecanismos de desativação não radiativa. Na presença de uma camada receptora, a eficiência de transferência de energia é maior para amostras com segmentos mais diluídos indicando que esse mecanismo compete com os processos internos à própria camada emissiva. O tempo de vida aumenta em filmes com mais baixo grau de conjugação e a dependência com o comprimento de onda de emissão é mais forte. Em resumo, a técnica de automontagem se mostrou adequada para obter filmes com propriedades fotofísicas controláveis no nível molecular, que puderam ser estudadas com espectroscopias de fluorescência. / Understanding the pathway of excitation in conjugated polymers is important for using these materials as active layer in devices, photovoltaic cells and sensors. In this thesis, non-radiative processes in layer-by-layer (LbL) films were investigated with measurements of fluorescence quenching in steady-state fluorescence spectroscopy and of the singlet excited state lifetime using time-resolved fluorescence spectroscopy in a single photon counting (SPC) apparatus. The emissive layer of poly(p-phenylene vinylene) (PPV) obtained via thermal conversion of the soluble precursor poly(xylylidene tetrahydrothiophenium) chloride (PTHT) showed lifetime 150-250 ps and weak dependence on the emission wavelength. In the presence of an acceptor layer of either Congo Red (CR) or nickel tetrasulfonated phthalocyanine (NiTsPc) the PL intensity was quenched and the lifetime was shorter (50 -100 ps). Upon increasing the distance between the energy donor (PPV) and acceptor layers by interposing bilayers of inert polyelectrolytes the dynamics tended to the PPV dynamics. The distance-dependence of the energy transfer efficiency (1/r2 or 1/r3) points to a resonant process (RET) with a plane-to-plane or plane-to-slab interaction. The non-radiative processes were also studied for varying dilutions of the PPV segments in a matrix of the polyelectrolyte poly(dodecyl methylamonium chloride) (PDAC). This dilution increased the quantum efficiency and led to longer lifetimes (500 ps) owing to a less effective non-radiative energy transfer. When an energy acceptor layer is present, energy transfer is more efficient for the most diluted systems, indicating that such transfer competes with internal processes in the emissive layer. The lifetime increased in films with low degree of conjugation, for which there was a stronger dependence on the emission wavelength. It is concluded that the LbL methodology was suitable to obtain photophysical film properties that could be controlled at the molecular level, and investigated with varied fluorescence spectroscopies.

The master’s thesis deals with the methods and system for measurement of concentration of intracellular calcium in LabVIEW. The thesis included theoretical and practical parts. The thesis covers the theory of fluorescence principles, fluorescence methods and indicators for measurement of concentration of intracellular calcium. The procedure of measurement by means of fluorescence microscope, camera and indicators is also mentioned. Literary solution is presented. Block diagram of system for measurement of concentration of intracellular calcium at a graphical programming environment LabVIEW is presented in practical part of master’s thesis.

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