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Phenolic profile and carbohydrate digestibility of durum spaghetti enriched with buckwheat flour and branBiney, Kuuku 09 September 2013 (has links)
There is growing demand for functional foods and ingredients as a result of their health-promoting properties. In this work, the potential of common buckwheat flour (Supreme) and bran (Farinetta) in improving upon the phenolic and antioxidant properties of durum spaghetti was investigated. The effects of processing and cooking on these properties were also studied in addition to the cooking quality and carbohydrate digestibility of spaghetti products. Among uncooked spaghetti samples, there were huge increments of between 114 and 522% for TPC, 50 and 242% for TFC, 359 and 1000% for DPPH antioxidant activity, and 101 and 197% for ORAC values of the experimental spaghetti samples over the control. Farinetta contributed more phenolic and antioxidant compounds than Supreme flour. Processing resulted in losses ranging from 1.2 to 33.7% in TFC and 42.0 to 55.3% in DPPH antioxidant activity. Cooking also resulted in significant losses (p < 0.05) of up to 39% in TPC, 40% in DPPH antioxidant activity, 22% in rutin content, and 55% in TFC in experimental samples. Cooking losses of up to 8.82% were recorded for the experimental samples and were higher in Farinetta-substituted products. These were generally higher than that of the control (6.33%). The introduction of buckwheat increased carbohydrate digestibility of products, but at the same time resulted in an overall lower release of reducing sugars after of 120 min of in vitro hydrolysis. Results show that the phenolic and antioxidant properties of durum spaghetti fortified with buckwheat milling fractions can compare favourably with those of 100% whole buckwheat pasta, and at the same time, maintain a higher cooking quality due to the presence of semolina.
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A biomimicking approach for hemicellulose processingOinonen, Petri January 2014 (has links)
Lignocellulose can become the best opportunity for the society to reduce its dependency on the harmful petroleum based products as well as to produce clean energy. In each part of the production cycle, biomass based products have a better environmental profiles than their petroleum based counterparts. Woody biomass has a vast availability, but it suffers from recalcitrance that is mostly caused by lignin that is functioning as a matrix, surrounding and binding the carbohydrates that are currently the most valuable of the wood components. Lignin-carbohydrate (LC) bonds are believed to be a key element in this recalcitrance and research has shown that these types of bonds are common in wood. These bonds are important in an economical point of view as well, as e.g. residual lignin structures in pulp (lignins bonded to the cellulose and hemicelluloses) require expensive bleaching sequences for their removal. The LC-structures can also be exploited technically as we now have demonstrated. We developed a method that utilizes phenolic end groups that are bonded to different hemicelluloses for cross-linking. The enzyme laccase was used for the cross-linking to create a cost-efficient processing scheme to both isolate and increase the molecular weight of the hemicelluloses. Membrane filtration was used as the key separation technique, which enables the establishment of industrial scale production. The final product had improved mechanical and thermal properties and could be used e.g. as barrier film component in renewable packaging. Nanocomposite formation with nanofibrillated cellulose was also studied. This improved the film properties further. The complexes are also possible to use as model compounds for lignin-carbohydrate complexes in wood. This technique can also be seen to mimick the lignification and lignin-carbohydrate network formation phenomena in plants enabling the formation of entire networks of wood components. Our results suggests that the side chains of hemicellulose might play an important role in network formation and that hemicellulose molecules can carry more than one lignin phenolic end group to fulfill this capability. / <p>QC 20140825</p>
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Frulle & Yo-Yo : Frukostens inverkan på psykofysiologisk prestationKronstrand, Anneli, Johansson, Simon January 2013 (has links)
Kost är ett brett ämne i dagens samhälle. Idag läggs ett stort fokus på barn och ungdomars prestation i skolan. Är det bara duktiga lärare som hjälper eleverna framåt eller finns det andra faktorer? Vi som blivande idrottslärare vill se hur mycket frukostens betydelse har på elevernas fysiska prestation. Eftersom kropp och själ hänger ihop har eleverna även fått skatta den upplevda fysiska ansträngningen. Därför kallar vi det för psykofysiologisk ansträngning. Som teoretisk utgångspunkt har vi använt oss av Maslows behovstrappa och kroppens energiprocesser. Detta är något som vi vill kunna ta med oss i framtiden. Vi vill inte bara se eleverna som kärl som vi sedan fyller på med kunskap, utan vi vill även testa detta praktiskt i hopp om att detta ska ge eleverna och oss en ny erfarenhet. Vårt syfte med undersökningen var att se frukostens inverkan på den psykofysiologiska prestationen. Presterar man lika bra i kropp och knopp med frukost respektive utan? Vi utförde ett praktiskt experiment på 29 elever. De fick utföra en standardiserad lektion som bestod av ett steptest och Yo-Yo-test, som är ett mätbart fysiskt test, med frukost respektive utan frukost. Eleverna fick sedan uppskatta sin fysiska ansträngning på Borgskalan som fanns med i en enkät. Resultatet visade att ansträngningen blev högre utan frukost både hos tränade och otränade. Observationen visade även att huvudvärk och mer upplevd trötthet uppstod vid tillfället utan frukost.
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The effect of alterations in diet composition upon anthropometric measures, biochemical parameters, and nutrient intakes in overweight womenCook, Darci L. January 2005 (has links)
Thirty-seven overweight/obese (BMI: 25-35 kg/m2), premenopausal women that were randomly assigned to either an ad libitum low-carbohydrate (LC) (20% CHO, 30-40% protein, 30-40% fat), or an ad libitum low-fat (LF) (55-60% CHO, 15-20% protein, 20-25% fat) diet.All subjects were given weekly menus matching their assigned macronutrient requirements to aid in meal planning and dietary compliance. Baseline and post-diet measures included height, weight, body composition (DXA), blood lipids [total cholesterol (TC), HDL, LDL, and triglycerides (TG)], and plasma insulin levels. There were no significant group differences in any of the above-listed variables prior to the study. Nineteen women completed the 6-wk study (LC=11, LF=8). Compliance to the diets was adequate as indicated by weekly 24-hr recalls and daily urinary ketone levels. Both groups lost a significant amount of weight and body flat, (P<0.05); and weight and body fat losses were not significantly different between the groups. All groups experienced similar decreases in TG, TC, LDL, HDL, and insulin levels. These results indicate a LC diet is no more effective than a LF diet in promoting favorable changes in body weight, body composition, blood lipids and insulin levels. / Department of Family and Consumer Sciences
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Phenolic profile and carbohydrate digestibility of durum spaghetti enriched with buckwheat flour and branBiney, Kuuku 09 September 2013 (has links)
There is growing demand for functional foods and ingredients as a result of their health-promoting properties. In this work, the potential of common buckwheat flour (Supreme) and bran (Farinetta) in improving upon the phenolic and antioxidant properties of durum spaghetti was investigated. The effects of processing and cooking on these properties were also studied in addition to the cooking quality and carbohydrate digestibility of spaghetti products. Among uncooked spaghetti samples, there were huge increments of between 114 and 522% for TPC, 50 and 242% for TFC, 359 and 1000% for DPPH antioxidant activity, and 101 and 197% for ORAC values of the experimental spaghetti samples over the control. Farinetta contributed more phenolic and antioxidant compounds than Supreme flour. Processing resulted in losses ranging from 1.2 to 33.7% in TFC and 42.0 to 55.3% in DPPH antioxidant activity. Cooking also resulted in significant losses (p < 0.05) of up to 39% in TPC, 40% in DPPH antioxidant activity, 22% in rutin content, and 55% in TFC in experimental samples. Cooking losses of up to 8.82% were recorded for the experimental samples and were higher in Farinetta-substituted products. These were generally higher than that of the control (6.33%). The introduction of buckwheat increased carbohydrate digestibility of products, but at the same time resulted in an overall lower release of reducing sugars after of 120 min of in vitro hydrolysis. Results show that the phenolic and antioxidant properties of durum spaghetti fortified with buckwheat milling fractions can compare favourably with those of 100% whole buckwheat pasta, and at the same time, maintain a higher cooking quality due to the presence of semolina.
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Small Molecule Ice Recrystallization Inhibitors and Their Use in Methane Clathrate InhibitionTonelli, Devin L. 05 April 2013 (has links)
Inhibiting the formation of ice is an essential process commercially, industrially, and medically. Compounds that work to stop the formation of ice have historically possessed drawbacks such as toxicity or prohibitively high active concentrations. One class of molecules, ice recrystallization inhibitors, work to reduce the damage caused by the combination of small ice crystals into larger ones. Recent advances made by the Ben lab have identified small molecule carbohydrate analogues that are highly active in the field of ice recrystallization and have potential in the cryopreservation of living tissue.
A similar class of molecules, kinetic hydrate inhibitors, work to prevent the formation of another type of ice – gas hydrate. Gas hydrates are formed by the encapsulation of a molecule of a hydrocarbon inside a growing ice crystal. These compounds become problematic in high pressure and low temperature areas where methane is present - such as an oil pipeline.
A recent study has highlighted the effects of antifreeze glycoprotein, a biological ice recrystallization inhibitor, in the inhibition of methane clathrates. Connecting these two fields through the synthesis and testing of small molecule ice recrystallization inhibitors in the inhibition of methane hydrates is unprecedented and may lead to a novel class of compounds.
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The influence of carbohydrate-electrolyte ingestion on metabolism and soccer skill performance during and following prolonged intermittent exerciseAli, Ajmol January 2002 (has links)
Although soccer is one of the more researched intermittent team sports, there is a surprisingly modest amount of information available on the effects of fatigue on skill performance. The main reasons for this are due to the problems of overcoming the barriers of controlling the many variables in the field and a lack of reliable and valid skill tests. The Loughborough Intermittent Shuttle running Test (LIST) is a recently developed exercise protocol which closely simulates the demands of multiple-sprint sports such as soccer in a controlled environment. Furthermore, the Loughborough Soccer Passing Test (LSPT) and Loughborough Soccer Shooting Test (LSST) were developed (and modified further as part of this thesis, Chapters 5 and 6) and found to be reliable and valid indicators of soccer skill. Therefore, one of the main aims of this thesis was to investigate the influence of 90 min of the LIST on soccer skill performance. Early researchers (e. g. Karlsson, 1969 and Saltin, 1973) reported the -benefits of maintaining a high muscle glycogen content on soccer performance and more recent investigators looked at the effect of providing carbohydrate (CHO) during exercise on work rate and soccer skill. However, many of these experiments were completed in the field setting and used poor tests of skill. Therefore, the primary aim of these series of experiments was to determine the influence of ingesting a carbohydrate-electrolyte (CHO-E) solution during the LIST on soccer skill performance. There was an 8% deterioration in LSPT performance following 90 min of intermittent high-intensity running, even with fluid ingestion (p<0.05). Furthermore, the ingestion of a CHO-E solution during exercise showed tendencies for better maintenance of skill performance towards the end of exercise. Moreover, CHO-E supplementation better maintained sprint performance and a higher relative exercise intensity during exercise (p<0.05). This is crucial in soccer perfon-nance, as players who are unable to sprint to get to the ball will be unable to perform the necessary skill. From the results of Chapters 5 and 6 it was found that the modified passing (LSPT) and goal-shooting (LSST) tests were valid and reliable tests of soccer skill. Moreover, they were found to be more repeatable when higher calibre players performed the tests. As in previous studies there was a speed-accuracy trade-off' in LSST performance i. e. subjects increased the time taken to complete each shot sequence and reduced the shot speed to maintain shooting accuracy post-LIST. There was a trend for CHO-E ingestion to maintain a better shot speed and time taken for each sequence. The ingestion of CHOE also reduced the perception of effort (p<0.05) and led to more positive feelings of affective valence during the last 30 min of the LIST. Therefore, based on these findings, it was concluded that the ingestion of CHO-E solutions over water alone should be encouraged to soccer players because of the tendency to better maintain soccer skill and the associated physiological, biochemical and psychological benefits during such exercise.
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Elucidating the Metabolic Function of RORalpha and gamma in Skeletal MuscleSurya Prakash Unknown Date (has links)
Nuclear Hormone Receptors (NRs) are hormone dependent DNA binding proteins that translate physiological signals into gene expression. Gene products have been identified that belong to the NR superfamily on the basis of homology. However, the endogenous and /or synthetic ligands that regulate their activity remain unknown, consequently, this subgroup of proteins are designated as orphans). Retinoic acid receptor related orphan receptors alpha and gamma(RORα and γ) are orphan NRs, and are preferentially expressed in skeletal muscle a major metabolic tissue and other tissues including pancreas, thymus, prostate, liver, adipose and testis. Surprisingly, the specific roles of ROR α and γ in skeletal muscle, a peripheral tissue, have not been examined. Muscle is one of the most energy demanding tissues which accounts for ~40% of the total body mass and energy expenditure, ~75% of glucose disposal and relies heavily on β-oxidation of fatty acids. We hypothesize that ROR α and γ regulates metabolism in this major mass lean tissue. Initially, this hypothesis was examined by “gain and loss” of function studies in an in-vitro mouse skeletal muscle cell culture model. Previous in vitro studies analyzed the role of RORα in the regulation of lipid homeostasis in skeletal muscle cells. We similarly conducted in vitro RORγ gain and loss of function studies in skeletal muscle cells to understand the role of this isoform in metabolism. We utilized stable ectopic over-expression of VP16-RORγ (gain of function), native RORγ and RORγΔH12 (loss of function) vectors to modulate RORγ mRNA expression and function. Candidate driven expression profiling of lines that ectopically express the native and variant forms of RORγ suggested that this orphan NR has a function in regulating the expression of genes that control lipid homeostasis (fatty acid-binding protein 4), CD36 (fatty acid translocase), lipoprotein lipase and uncoupling protein 3), carbohydrate metabolism (GLUT5 (fructose transporter), adiponectin receptor 2 and interleukin 15 (IL-15)) and muscle mass (including myostatin and IL-15). Interestingly, our study revealed a function for RORγ in the pathway that regulates production of reactive oxygen species which was also correlated with increased expression of UCP3 mRNA. Subsequently, we conducted in vivo studies with mouse models displaying global and muscle specific perturbation in RORα expression and function to elucidate the physiological role of this orphan NR in the context of metabolism.Along these lines, we characterized homozygous staggerer mice (sg/sg) in the context of lipid, carbohydrate and energy homeostasis. Staggerer mice were characterized by decreased and dysfunctional retinoic acid receptor-related orphan receptor alpha (RORα) expression. We observed decreases in serum (and liver) triglycerides and total and high density lipoprotein serum cholesterol in staggerer mice. Moreover, the staggerer mice were associated with reduced adiposity, decreased fat pad mass and adipocyte size. Candidate-based expression profiling demonstrated that the dyslipidemia in staggerer mice was associated with decreased hepatic expression of SREBP-1c, and the reverse cholesterol transporters, ABCA1 and ABCG1. This was consistent with the reduced serum lipids. Furthermore, the lean phenotype in staggerer mice was also characterized by significantly increased expression of PGC-1α, PGC-1β, and lipin1mRNAin liver and white and brown adipose tissue from staggerer mice. In addition, we observed a significant 4-fold increase in β2-adrenergic receptor mRNA in brown adipose tissue. Finally, dysfunctional RORα expression protects against diet-induced obesity. Following a 10-week high fat diet, wild-type (but not sg/sg) mice exhibited a ~20% weight gain, increased hepatic triglycerides, and notable white and brown adipose tissue accumulation. In summary, these changes in gene expression (that modulate lipid homeostasis) in metabolic tissues were involved in decreased adiposity and resistance to diet induced obesity in the sg/sg mice, despite hyperphagia. Finally, we specifically modulated RORα signaling in skeletal muscle by the targeted over-expression of truncated RORαΔDE (lacking the ligand binding domain) driven by a myogenic specific promoter, to investigate the contribution of this peripheral tissue to the RORα phenotype. Interestingly, transgenic heterozygous animals exhibit increased fasting blood glucose levels and mild glucose intolerance. Expression profiling (and western analysis) identified perturbations in the insulin signaling cascade. For example, we observed attenuation of p85alpha (PI3K) and Akt2 (mRNA and protein) expression; and insulin dependent induction of phospho-Akt2. In concordance, significantly increased levels of active phospho-AMPK were detected in the muscle of transgenic mice (relative to wt littermates). The increase in phospho-AMPK correlated with: (i) the suppression of lipogenic gene expression; and (ii) increased phospho-ACC and activation of genes involved in fatty acid oxidation in the skeletal muscle of transgenic animals. In conclusion, we suggest these orphan nuclear receptors (RORα and γ) are key modulators of fat and carbohydrate homeostasis in skeletal muscle tissue. Specifically, we propose that, RORα plays vital role in fat accumulation in adipose tissue and insulin mediated glucose homeostasis in skeletal muscle. Therefore we suggest that selective muscle specific RORα modulators may have utility in the treatment of type2 diabetes and obesity.
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Plant UDP-glucose pyrophosphorylase : function and regulation /Meng, Meng, January 2008 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2008. / Härtill 4 uppsatser.
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Utilização de carboidratos digestíveis em dietas para pacu, Piaractus mesopotamicus (Holmberg, 1887)Muñoz Ramírez, Adriana Patrícia [UNESP] 09 March 2005 (has links) (PDF)
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munozramirez_ap_dr_jabo.pdf: 1583647 bytes, checksum: e90e70f6a7dfe33508bb2e8d729ac986 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O valor nutricional dos vários tipos de carboidratos parece estar relacionado com sua complexidade. A utilização quantitativa e qualitativa de sete diferentes fontes de carboidratos (amido de milho regular, amido de milho ceroso, amido de milho regular pré-gelatinizado e modificado, fécula de mandioca modificada e pré-gelatinizada, dextrina, maltodextrina e glicose-dextrose) em dietas para o pacu foi estudada, para verificar o efeito sobre o desempenho, eficiência nutricional, metabolismo energético e atividade amilásica no trato gastrintestinal. Num ensaio de digestibilidade foram estudadas sete fontes de carboidratos em dois níveis de inclusão (20 e 40%). Utilizaram-se 14 dietas semipurificadas isoprotéicas contendo farinha de peixe, carboximetil celulose, celulose microfina, óleo de soja e suplemento mineral e vitamínico. Para a coleta de fezes utilizaram-se coletores seguindo o sistema Guelph modificado. Foram determinados os coeficientes de digestibilidade aparente da matéria seca, dos nutrientes (proteína bruta, extrato etéreo, extrativo não nitrogenado) e da energia das dietas. No segundo ensaio foi avaliado o crescimento de juvenis de pacu, durante 60 dias em condições de laboratório, utilizando-se 126 peixes com peso médio de 49,1l8,3 g. Nos peixes alimentados com sete dietas semipurificadas isoprotéicas peletizadas, contendo 40% de cada uma das fontes de carboidratos foram avaliados os parâmetros de desempenho, composição corporal e eficiência de utilização de nutrientes e energia. Adicionalmente, três peixes de cada parcela do ensaio de crescimento foram sacrificados e amostras de sangue, fígado, músculo e trato gastrointestinal foram coletadas e processadas. Foram avaliados os índices hepatosomático e viscerosomático e o metabolismo energético por meio da determinação dos intermediários metabólicos:... / The nutritional value of many forms of carbohydrates seems to be related to its complexity. The quantitative and qualitative utilization of seven different carbohydrates sources (regular corn starch, waxy corn starch, pregelatinized and modified regular corn starch, modified and pregelatinized cassava starch, dextrin, malt dextrin, and glucose-dextrose) on diets for pacu were studied, aiming to achieve maximum performance efficiency and reduce costs of protein use. Fourteen semipurified isoproteic pelletized diets were used in a nutrient and energy digestibility trial of the carbohydrate sources, with a basic nutrient composition (fish meal, carboxymethyl cellulose, fine cellulose, soybean oil, mineral, and vitamin supplement) and two levels (20 and 40%) of included carbohydrates sources. Feces of 480 juveniles' pacu (69.6l17.9 g) were collected using collectors according Guelph modified system. Dry matter, nutrients (crude protein, ether extract, and nitrogen free extract), and energy apparent digestibility coefficients of the diets were determined. The second trial, conducted for 60 days in the laboratory, evaluated the growth of juveniles pacu of 126 fishe with average weight of 49.1l8.3g. The parameters of productive performance, body composition, nutrients, and crude energy utilization efficiency of fish fed semipurified isoproteic pelletized diets, each containing 40% of the studied carbohydrates sources, were evaluated. On the last trial, three fishes of each plot of the growth trial were sacrificed and samples of blood, liver, muscle, and gastrointestinal tract were collected and processed. The hepatosomatic and visceralsomatic indexes and energetic metabolism were evaluated by determining metabolic mediators: plasmatic glucose, cholesterol and total proteins, hepatic and muscular glycogen, plasmatic triglyceride and iv free amino acids, hepatic and muscular free fatty acids... (Complete abstract, click electronic address below).
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