Orientadores: Telma Teixeira Franco, Gustavo Paim Valença / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-26T21:59:10Z (GMT). No. of bitstreams: 1 Ayres_BiancaMairaTeixeira_D.pdf: 23160216 bytes, checksum: 967289613483c430d41cd88562085d44 (MD5) Previous issue date: 2014 / Resumo: O objetivo deste trabalho foi a biocatálise de acrilatos de carboidratos, desde glicose até maltodextrina. Maltodextrinas (MD) são produtos da hidrólise do amido, caracterizadas por cadeias de 5 a 20 unidades de ?-D-glicose unidas por ligações ?-1,4 (principalmente). Análises por cromatografia de permeação em gel (HPSEC) caracterizou ampla distribuição de massa molar de amostras padrão ou industriais de MD, apresentando de 1 a 100 unidades de glicose (G1). O fracionamento por etanol para seleção de menores cadeias de glicose não foi efetivo pois variadas frações volumétricas de etanol forneceu contaminação de cadeias curtas no precipitado. Os principais fatores limitantes para a esterificação enzimática da MD com ácido acrílico são baixa solubilidade do substrato sacarídico, inibição por ácido acrílico, polaridade do solvente orgânico que permita atividade enzimática, a qual depende das características da lipase imobilizada como tipo de suporte e origem da lipase. Lipases disponíveis comercialmente na forma imobilizada de Thermomyces lanuginosa (TL IM) ou Candida antarctica (Novozyme 435) e, imobilização por adsorção das lipases de T.lanuginosa, C.antarctica, Candida rugosa e Rizomucor miehei em Accurel EP-100 foram investigadas em triagem associada de solventes orgânicos. Dioxano e Novozyme 435 foram a melhor associação que alcançou maior conversão de G1 e G2. Acrilatos de maltodextrina foram também observados sob incubação com TL IM em TBA. A solubilidade da MD é completa em água, piridina e DMSO, cerca de 1 kg L-1, mas as lipases não são ativas para esterificação nestes solventes. A água é um subproduto da esterificação e sua presença pode deslocar a reação em favor da hidrólise. A adição de DMSO como co-solvente para o sistema reacional contendo 2M2B ou TBA foi comprovado ser menos eficiente que sistemas com 100% dos solventes apolares. A maior área de taxa de aumento da produção direta de acrilatos de maltodextrina foi alcançada com 2-metil-2- butanol como meio reacional. Analogicamente, a acrilação enzimática de n-butanol foi catalisada pela Novozyme 435. Diferentemente dos acrilatos de carboidratos, o produto acrilato de butila pôde ser quantificado por cromatografia em fase gasosa (CG). Sistemas de solventes e co-solventes (tolueno, ciclohexano, 2-metil-2-butanol (2M2B), álcool terc-butílico (TBA) e associações com parcial volume de dimetilsulfoxido (DMSO)) foram estudados para determinar o efeito destes na atividade enzimática específica. O uso de ciclohexano e tolueno resultaram em atividade da enzima três vezes maior que em TBA e 2M2B. n-Butanol e MD são substratos diferenciados pela solubilidade nos solventes orgânicos, os quais devem ser apolares ou pouco polares para permitir atividade catalítica. Uma reação secundária de acrilação com o solvente orgânico, TBA ou 2M2B, foi verificada por cromatografia gasosa acoplada à espectrometria de massas. A esterificação enzimática de maltose, de maltotriose e maltodextrina com ácido acrílico catalisada pela lipase Novozyme 435 em 2M2B foram analisadas por espectrometria de massas com ionização por eletrospray, ou acoplada à cromatografia líquida de alta eficiência. Essas análises confirmaram a presença de uma até quatro hidroxilas acriladas da maltose (G2) ou da maltotriose (G3). Um processo em duas etapas de biocatálise para produção de acrilatos de carboidratos foi investigado. Inicialmente, G1 ou G2 foram esterificadas enzimaticamente com propionato de vinila ou acrilato de etila por incubação com Novozyme 435 em dioxano. Em subsequente etapa, a cadeia glicosídica destes ésteres foram alongadas a partir da atividade da cicloglicosil transferase de Bacillus macerans com ?-ciclodextrina como doador de grupo glicosil. Cromatografia líquida de alta eficiência com detecção amperométrica e aerossol carregado e cromatografia em camada delgada foram utilizados para identificar os ésteres de oligossacarídeos. Cerca de 75% ou 55% de ?-ciclodextrina foi convertida com consumo de 40.5% de propionato de glicose (G1P) ou 86.3% de propionato de maltose (G2P) pela atividade da CGTase. A composição da solução final foi, desde 2 a 14 unidades de glicose com uma unidade acrilada ou propilada / Abstract: The aim of this work was the biocatalysis of the acrylates of carbohydrates, from glucose up to maltodextrins. Maltodetrins (MD) are starch hydrolysates consisting of ?-D-glucose units bounded by ?-1,4 glycosidic linkages (primarily). Analysis of standard or industrial samples of MD in gel permeation chromatography presented a huge molecular mass distribution, from 1 to 100 units of glucose (G1). An ethanol fractionation step for selection of narrow range of the chains of glucose was unsuccesfull because the precipitate and supernatant were contamined with small molecules. The main limitant factors for enzymatic esterification of MD with acrylic acid are the catering saccharidic substrate (increase its solubility) to the lipase, to avoid (or overcome) inhibition from acrylic acid, and to allow enzymatic activity, which depends on the characteristics of the immobilized lipases (type of support, source of the lipase) and solvent of the system. Commercial immobilized lipases from Thermomyces lanuginosa (TL IM) or Candida antarctica (Novozyme 435) and, lipases from T.lanuginosa, C.antarctica, Candida rugosa and Rizomucor miehei immobilized by absorption in Accurel EP-100 were investigated in a screening of organic solvents. Dioxane and Novozyme 435 were the best association for higher conversion of G1 and G2. TL IM in tert-butanol (TBA) was the only system, which produced acrylates of maltodextrina on TLC plates. The solubility of the MD is complete in water, pyridine and dimethylsulfoxide (DMSO), about 1 kg L-1, but lipases are not active for esterification in these solvents. The water is a byproduct of the esterification and shifts the reversible reaction toward the hydrolysis. The partial addition of the co- solvent DMSO to the reactional system containing 2-methyl-2-butanol (2M2B) or TBA was tested for partial solubilization of the maltodextrin. The systems with only one organic solvent were more efficient than the presence of DMSO. The highest area in high performance liquid chromatography (HPLC) for production of the MD acrylates was achieved with 2M2B as adjuvant. Analogically, the acrylation of n-butanol by Novozyme 435 was studied to better understand the enzymatic acrylation, since the quantification of the product butyl acrylate is possible by gas chromatography (GC). Solvent systems (toluene, cyclohexane, 2M2B, TBA and partial volume of DMSO) were studied to determine the effect of the solvents on the specific enzymatic activity. It was found that cyclohexane and toluene achieved 3-fold the enzyme activity that in TBA and 2M2B. However, n-butanol and MD as substrate are mainly differentiated regards to the solubility in non polar organic solvents which are more suitable for lipase activity. A side reaction of acrylation of the organic solvent, TBA or 2M2B, was verified by GC-Mass Spectrometry. Meanwhile, the enzymatic esterification of maltose, maltotriose and maltodextrin with acrylic acid by Novozyme 435 in 2M2B were analyzed in electrospray ionization (ESI) mass spectrometry (MS) associated to HPLC, which confirmed the presence of mono- until tetra- acrylated hydroxyls for maltose (G2) and maltotriose (G3). A two-step process of biocatalysis for producton of sugar acrylates was investigated. G1 or G2 was acylated with either vinyl propionate or ethyl acrylate by Novozyme 435 in dioxane. Then, the elongation of the chain by cyclodextrin glucanotransferase (CGTase) from Bacillus macerans with ?-cyclodextrin as acyl donor provided maltoligosaccharides esters. CGTase from Bacillus macerans converted these products from the first step and ?-cyclodextrin into oligosaccharide esters. HPLC coupled to charged aerosol detector and amperometric exchange and thin layer chromatography were used to identify the oligosaccharide esters. About 75% or 55% of ?-cyclodextrin was converted under consumption of 40.5% of glucose propionate (G1P) or 86.3% of maltose propionate (G2P) by CGTase activity. The composition of the final solution was since 2 to 14 glucose units with one acrylate or propionate moiety / Doutorado / Engenharia Química / Doutora em Engenharia Quimica

O cerrado é o segundo maior bioma do país, ocupando em torno de 20 a 25% do território brasileiro, sendo detentor de grande diversidade vegetal. Entretanto, agressões a áreas de cerrado vêm ocorrendo em escala crescente, o que torna urgente estudos detalhados sobre espécies representativas do bioma. O objetivo deste trabalho foi o de analisar o conteúdo de nutrientes orgânicos das sementes de leguminosas, uma das famílias de maior riqueza no cerrado. Foram analisados lipídios, carboidratos e proteínas de oito espécies: Acosmium subelegans, Anadenanthera peregrina var. falcata, Andira laurifolia, Copaifera langsdorfii, Crotalaria flavicoma, Dimorphandra mollis, Hymenaea stigonocarpa e Inga uraguensis. Em geral, as amostras apresentaram baixos teores de lipídios (aproximadamente 5%) e a composição de ácidos graxos mostrou predominância do ácido linoléico na maioria das espécies e também uma tendência a alta proporção de ácidos graxos saturados, principalmente ácido palmítico. A espécie com maior teor foi Acosmium subelegans (13%), que apresentou valor comparável ao de semente de lupino e sua composição de ácidos graxos é similar aos de óleos de girassol, gergelim e milho. As espécies apresentaram teores consideráveis de açúcares solúveis totais (5-10%). Os rendimentos de amido foram baixos (inferior a 1%), com exceção de Inga uraguensis (17,86%) e Andira laurifolia (56,27%). Esta última apresentou valores similares aos de espécies comumente utilizadas na alimentação, como feijões, ervilha e lentilha. Foram obtidos teores de proteínas de 9 a 30% e as espécies com maiores valores foram Crotalaria flavicoma (25%), Acosmium subelegans (28,34%) e Anadenanthera peregrina var. falcata (30,35%). Essas três espécies possuem teores semelhantes e até superiores aos de algumas leguminosas, como feijão comum, lentilha, ervilha e amendoim, embora seja inferior ao da soja. Entretanto, em Leguminosae é freqüente a presença de diversos fatores anti-nutricionais e tóxicos, que devem ser avaliados antes de se sugerir uma potencial utilização das sementes dessas espécies na alimentação humana e de animais. / Cerrado (Brazilian savanna) is one of the largest biomes in the country, covering about 20 to 25% of the Brazilian territory and housing a wide biodiversity. However, Cerrado vegetation has undergone an increasing degree of aggression. Thus, detailed studies about Cerrado plant species are urgently needed. The aim of this work is to analyse organic nutrients of seeds of representative Cerrado species. Leguminosae is one of the predominant families of the Cerrado flora. Analysis of contents of lipids, carbohydrates, and proteins were carried out, involving eight species: Acosmium subelegans, Anadenanthera peregrina var. falcata, Andira laurifolia, Copaifera langsdorfii, Crotalaria flavicoma, Dimorphandra mollis, Hymenaea stigonocarpa e Inga uraguensis. Regarding most species, the seed samples analysed has low oil contents and the fatty acid compositions are characterized by the predominance of linoleic acid. A trend was observed toward high levels of saturated fatty acids, mainly palmitic acid. Acosmium subelegans showed the highest lipid content (13%), comparable to lupin seeds, and its fatty acid composition was similar to sunflower, sesame and corn oils. All samples analysed contain relatively high amounts of total soluble sugar (5-10%), which include oligosaccharides. Starch contents of most samples were low (below 1%), except for Inga uraguensis (17,86%) and Andira laurifolia (56,27%). The latter value is similar to those reported for commom seed foods, such as beans, peas and lentils. Crude protein contents ranged from 9 to 30%, the species with higher values being Crotalaria flavicoma (25%), Acosmium subelegans (28,34%) and Anadenanthera peregrina var. falcata (30,35%). The protein content of seeds of these species are similar and even higher than those reported for commonly cultivated legumes, such as bean, lentil, pea and peanut, although lower than soybean content. Several antinutritional and toxic components are frequent in Leguminosae seeds, so that the presence of these substances has to be considered before any suggestion regarding utilization of these species in human and animal nutrition may be put forward.

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The purpose of this study is to show that the method just proposed can be used for the synthesis of 2-halo benzyl glycosides. And these derivatives can be used to synthesize biologically interesting compounds which were not previously attainable using the 2-halo-2-deoxy methyl glycosides which are currently available.

This master‘s thesis deals with the analysis of 65 different beers, with a focus on finding differences between Czech tap ales, lagers Czech, Czech special beers and foreign beers. Czech beers were compared by the results of analysis among beers bearing the indication "Czech beer" and the group without this indication. The total amount of proteins, polyphenols and carbohydrates was determined using UV-VIS spectrometry. The history of brewing, the nature and types of Czech beers and protected geographical indication "Czech beer" were described. Raw materials for beer production and brewing technology have been listed and described. In the last part of the research, components of beer and the principle of the UV-VIS spectrometry have been specified. Th determination of total protein was performed using Hartree-Lowry method, which is based on two-component reagent. The first component is the biuret agent, the second component is the Folin-Ciocalteau reagent for phenols. Determination of the polyphenols has been carried out by the Folin-Ciocalteau reagent and total carbohydrates were determined spectrophotometrically according to the Analytica EBC using anthron agent. The results were statistically processed and evaluated in the final part.

It has been well established that both carbohydrate-loading before and carbohydrate ingestion during exercise can enhance endurance performance by supplying carbohydrate for oxidation. However, the precise mechanism(s) underlying the proposed ergogenic effects of these procedures remain to be established. The studies in this thesis were therefore designed to examine the effects of carbohydrate-loading and carbohydrate ingestion on fuel substrate kinetics.

On two occasions six competitive, male triathletes performed in random order, two experimental trials consisting of either a timed ride to exhaustion on a cycle-ergometer or a run to exhaustion on a motor-driven treadmill at 80% of their respective peak cycling and peak running oxygen uptakes (VO₂peak)- At the start of exercise, subjects drank 250 ml of a 15 g.100 ml⁻¹ w.v⁻¹ glucose solution with U-¹⁴C glucose added as tracer and, thereafter, 150 ml of the same solution every 15 min. Despite identical metabolic rates (VO₂ 3.51 ±0.06 vs. 3.51 ±0.10 l.min⁻¹; values are mean± SEM for the cycling and running trials, respectively), exercise times to exhaustion were significantly longer during cycling than running (96 ±14 vs. 63 ±11 min; P<0.05). The superior cycling than running endurance was not associated with any differences in either the rate of blood glucose oxidation (3.8 ±0.1 vs. 3.9 ±0.4 mmol.min⁻¹ ), nor the rate of ingested glucose oxidation (2.0 ± 0.1 vs. 1.7 ±0.2 mmol.min⁻¹) at the last common time point (40 min) before exhaustion, despite higher blood glucose concentrations at exhaustion during running than cycling (7.0 ±0.9 vs. 5.8 ±0.5 mmol.l⁻¹; P<0.05). However, the final rate of total CHO oxidation was significantly greater during cycling than running (24.0 ±0.8 vs. 21.7 ±1.4 mmol C6 .min⁻¹;P<0.01). At exhaustion, the estimated contribution to energy production from muscle glycogen had declined to similar extents in both cycling and running (68 ±3 vs. 65 ± 5%). These differences between the rates of total CHO oxidation and blood glucose oxidation suggested that the direct and/or indirect (via lactate) oxidation of muscle glycogen was greater in cycling than running.

Thesis. 1975. M.S.--Massachusetts Institute of Technology. Dept. of Nutrition and Food Science. / Bibliography: leaves 109-112. / M.S.

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No description available.