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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.
691

Analýza učebnic a tvorba učebních textů s tematickým celkem sacharidy a jejich metabolismus pro školy gymnaziálního typu / The analysis of the textbooks and the creating of the learning texts about the thematic unit of carbohydrates and their metabolism for the gymnasial grammar schools

Šmídl, Milan January 2013 (has links)
1 Abstract: The main parameters describing content and the accessibility of information from textbooks are many aspects such as text difficulty and others. Individual characteristics of pupils - that are represented by chosen student preconceptions and misconceptions - also belong to key factors. The providing of the comprehensive view of the issues regarding analysis and the linking of acquired pieces of knowledge with the practical textbook creation have been the main aims of this dissertation. The creation of an instructional text follows the analysis results of the topic carbohydrates and their metabolism in chosen textbooks and the preconception analysis of biochemical terms. The instructional text respects the results of the analysis. The theoretical background of textbook creation (the functions of textbooks, their structure, content, characteristics and investigated parameters) has been described in detail in the theoretical part of this doctoral thesis. It is followed by the survey of the information concerning student preconceptions and the possibilities for their analysis and use in teaching. The aspects of textbooks use from the perspective of pupils, teachers and publishers, as well as the relation of the topic carbohydrates and their metabolism to curriculum documents have been described in...
692

Efeitos da abreviação do jejum pré-operatório com carboidratos e glutamina na resposta metabólica de pacientes submetidos à colecistectomia videolaparoscópica. Estudo controlado randomizado duplo cego / The effects of the abbreviation of preoperative fasting with carbohydrate and glutamine on the metabolic response after videolaparoscopic cholecystectomy. A double blind randomized trial

Nascimento, Diana Borges Dock 05 April 2012 (has links)
Introdução: O jejum prolongado pré-operatório aumenta a resistência periférica à insulina. Foi investigado se a abreviação do jejum pré-operatório com uma bebida contendo carboidrato e glutamina melhora a resposta orgânica ao trauma cirúrgico. Métodos: Quarenta e oito pacientes adultas, do sexo feminino (19-62 anos) candidatas a colecistectomia videolaparoscópica eletiva. As pacientes foram aleatoriamente divididas em quatro grupos: grupo jejum convencional (grupo Jejum), ou em três grupos para receber três tipos diferentes bebidas oito horas (400 mL) e duas horas antes da indução anestésica (200ml): água pura (grupo Placebo), água mais dextrinomaltose (grupo carboidrato; 12,5% de dextrinomaltose) e grupo glutamina (grupo glutamina; 12,5% de dextrinomaltose e respectivamente 40 e 10g de glutamina). As amostras de sangue foram coletadas no período pré e pós-operatório. Resultados: não houve nenhum evento de aspiração ou regurgitação do conteúdo gástrico manifesto por sinais e sintomas clínicos, durante a indução anestésica, ou em qualquer outro momento do estudo. Também não houve nenhum óbito ou complicação pós-operatória. A média e o erro padrão médio da resistência à insulina determinada pelo HOMA-IR realizada no pós-operatório foi maior (p<0,05) no grupo que permaneceu em jejum (4,3±1,3) quando comparado com os outros três grupos de pacientes (Placebo, 1,6±0,3); carboidrato, (2,3±0,4) e glutamina, (1,5±0,1). A medida da glutationa peroxidase sérica, medida nos dois períodos foi maior no grupo glutamina (40±3,0) que nos grupos carboidrato (32±2,0) e jejum (32±2,0) (p<0,01). Ao se comparar o comportamento da IL-6 sérica em cada grupo estudado no período pré e pós-operatório, observou-se que o grupo glutamina foi o único sem diferença, enquanto nos demais a IL-6 aumentou no pós-operatório (p<0,01). No período pós-operatório a razão proteína-C-reativa/albumina foi maior no grupo jejum quando comparado com os grupos carboidrato (p=0,04) e glutamina (p=0,01). O balanço nitrogenado acumulativo foi menos negativo no grupo glutamina (-2,5±0,8 gN) que nos grupos placebo (-9,0±2,0 gN; p=0,001) e jejum (-6,6±0,4 gN; p=0,04). Conclusão: A abreviação do jejum pré-operatório com uma bebida contendo carboidrato e glutamina melhora a resistência periférica a insulina, a resposta anti-oxidativa e diminui a resposta inflamatória de pacientes submetidas à colecistectomia videolaparoscópica eletiva / Introduction: Prolonged preoperative fasting increases insulin resistance. We investigated whether an abbreviated preoperative fast with glutamine plus a carbohydrate based beverage would improve the organic response after surgery. Methods: Forty-eight female patients (19-62 years) candidates for video-cholecystectomy were randomized to either standard fasting (fasting group) or to fasting with one of three different beverages. Beverages were consumed 8 hours (400 mL; placebo group: water; glutamine group: water with 50 g maltodextrine plus 40 g glutamine; and carbohydrate group: water with 50 g maltodextrine) and 2 hours (200 mL; placebo group: water; glutamine group: water with 25 g maltodextrine plus 10 g glutamine; and carbohydrate group: water with 25 g maltodextrine) before anesthesia. Blood samples were collected pre- and postoperatively. Results: There were no cases of regurgitation during anesthesia. The mean [SEM] postoperative HOMA-IR was greater (p<0,05) in fasted patients (4,3±1,3) than in the other groups (placebo, 1,6±0,3); carbohydrate, (2.3±0,4); and glutamine, (1,5±0,1). Glutathione peroxidase (U/g hemoglobin) was significantly higher (40±3,0) in glutamine group than both carbohydrate (32±2,0) and fasting (32±2,0) groups (p< 0,01). Interleukin-6 increased in all groups except the glutamine group. The C-reactive protein/albumin ratio was higher in fasting subjects than carbohydrate (p=0,04) and glutamine (p=0,01) groups. The nitrogen balance was less negative in glutamine (-2,5±0,8 gN) than both placebo (-9,0±2,0 gN; p=0,001) and fasting (-6,6±0,4 gN; p=0,04) groups. Conclusions: Preoperative intake of a glutamine-enriched carbohydrate beverage improves insulin resistance and antioxidant defenses, and decreases the inflammatory response after videolaparoscopic cholecystectomy
693

Frigoconservação e vernalização de mudas de morangueiro (Fragaria x ananassa Duch.) produzidas em sistema de vasos suspensos. / Storage cold and vernalization of strawberries runner (fragaria x ananassa duch.) produced in suspend pots system.

Verdial, Marcelo Fontanetti 14 May 2004 (has links)
Com o objetivo de estudar o sistema de produção de mudas de morangueiro em vasos suspensos e a aplicação das técnicas de frigoconservação e vernalização nas mudas produzidas nesse sistema, foram realizados quatro experimentos no Departamento de Produção Vegetal, ESALQ/USP, Piracicaba/SP, no período compreendido entre janeiro de 2000 e junho de 2003. No primeiro experimento comparou-se o sistema de produção de mudas em vasos suspensos com o sistema convencional. Foram avaliados: matéria seca, teor de carboidratos totais e percentagem de sobrevivência de mudas. Foram utilizadas as cultivares IAC-Campinas, Pelican e IAC-Guarani. Foi utilizado o delineamento experimental em esquema fatorial 3x2 (três cultivares e dois sistemas de produção de mudas), com três repetições. As mudas produzidas em vasos suspensos apresentaram maior percentagem de sobrevivência e maiores teores de carboidratos totais. O segundo e terceiro experimentos tiveram como objetivo avaliar o uso da técnica de frigoconservação em mudas produzidas no sistema de vasos suspensos. As mudas foram acondicionadas em sacos de polietileno e frigoconservadas durante 120 dias em uma B.O.D. a -1 + 1oC. Foram então retiradas da câmara fria e plantadas em bandejas de poliestireno expandido de 128 células preenchidas com vermiculita. As bandejas foram colocadas em uma câmara nebulizadora, onde permaneceram por 21 dias para enraizamento. Em seguida foram transplantadas para vasos de 250ml e levadas para casa de vegetação. Foi avaliada a percentagem de sobrevivência das mudas. No segundo experimento utilizou-se o delineamento experimental inteiramente ao acaso com cinco cultivares (IAC-Campinas, Dover, Pelican, Sequoia e Sweet Charlie) e nove repetições. No terceiro experimento foi utilizado o esquema fatorial 5x2 (cinco cultivares: IAC-Campinas, Oso Grande, Camarosa, Dover e Sweet Charlie; e dois tratamentos de enraizamento: com e sem ácido indol butírico) com quatro repetições. O sistema de frigoconservação adotado apresenou desempenho insatisfatório devido à baixa percentagem de sobrevivência das mudas. O quarto experimento estudou o efeito da vernalização em mudas de cinco cultivares de morangueiro produzidas no sistema de vasos suspensos. As mudas foram plantadas em vasos de 250 ml, preenchidos com substrato formulado com areia e vermiculita (4:1) e mantidas em casa de vegetação durante seis meses. O delineamento experimental utilizado foi o fatorial 5x2, com cinco cultivares (IAC-Campinas, Dover, Sweet Charlie, Cartuno e Oso Grande) com e sem vernalização das mudas, com quatro repetições. Para vernalização, as mudas foram levadas para câmara fria, à temperatura de 10 + 2ºC, e fotoperíodo de 10 h de luz/dia, durante 28 dias. Em seguida, foram transplantadas para dois locais de cultivo com características climáticas distintas, Piracicaba,SP e Caldas,MG. Foram avaliadas as percentagens de sobrevivência, florescimento, frutificação e emissão de estolhos e o peso da matéria fresca e número de frutos produzidos por planta. A sobrevivência de mudas não foi afetada pela vernalização em nenhuma das localidades. Houve efeito significativo no florescimento e na frutificação das plantas vernalizadas apenas em Piracicaba. O estolonamento de plantas foi mais precoce em Piracicaba. Para todas as cultivares a produção de frutos foi e insignificante e comercialmente inviável em ambas as localidades. / With the objective of studying the runners production system in suspended pots under protected cultivation and the application of techniques of stored cold and vernalization of runners produced by this system, four experiments were conducted in the Department of Crop Production, ESALQ, Piracicaba, SP-Brazil. In the first experiment it was compared the conventional strawberry runners production system with the runner production system in suspended pots. For that, it was measured the dry matter and carbohydrates contents in runners and the survival percentage when the runner were transplanted to field production areas. The cultivars IAC-Campinas, Pelican and IAC-Guarani were used, in an experimental design of factorial arrangement 3x2 (three cultivars and two runners production systems), three replications. The runners produced by the system of suspended pots accumulated higher amount of total carbohydrates and the plant survival rate. The second and third experiments had the objective of evaluating the use of a technique of storage cold in runners produced in the system of suspended pots. After the selection, the runners were conditioned in polyethylene bags and storage cold conditions for 120 days in a B.O.D. at -1+1ºC. After that they were removed of the cold camera and planted in trays of expanded polystyrene of 128 cells with vermiculite. The trays were put in a spray chamber 21 days for rooting. After that hey were transplanted to pots of 250mL and then placed in the greenhouse. It was evaluated the percentage of runners survival. In the second experiment it was used the experimental entirely random design, five strawberry cultivars (IAC-Campinas, Dover, Pelican, Sequoia and Sweet Charlie), and nine repetitions. In the threat experiment the factorial outline used was 5x2 (five cultivars: IAC-Campinas, Big Oso, Camarosa, Dover and Sweet Charlie; and two treatments: with and without indol butyric acid) with four repetitions. The storage cold of strawberry runners produced in system of suspended pots lower percentage of survival of seedlings in the two experiments. Therefore, the system of storage cold was not compatible with the type of storage runners. The fourth experiment had the objective of studying the effect of the runner vernalization of five strawberry cultivars produced in suspended pot system. In order to have availability of strawberry runners during the off season, they were planted in pots of 250 mL, filled out with substrate formulated with sand and vermiculite (4:1) and kept in the greenhouse for six months. Completely randomized blocks with the factorial design 5x2, with five strawberry cultivars (IAC-Campinas, Dover, Sweet Charlie, Cartuno and Big Oso) and two treatments (with and without strawberry runners vernalization). For vernalization, the strawberry runners were taken from cold camera to the temperature of 10 + 2ºC, and fotoperiod of 10 h of light/day for 28 days. After that, they were transplanted for two cultivation places with different climatic conditions, Piracicaba/SP and Caldas/MG. They were analyzed the survival percentages, flower blooming, fructification and emission of stolons and the weight and number of fruits produced by plant. The strawberry runners survival was not affected by the vernalization in none of the places. There were only significant effect on flower appearance and fructification of the vernalized plants, only in Piracicaba. The runner emitions were earlier in Piracicaba. For all strawberry cultivars the production of fruits was very low and the produced fruits were unsuitable for commercialization in both places.
694

Isolamento e análise funcional do gene que codifica uma proteína serina-treonina quinase que modula a expressão de genes regulados por carboidratos em Trichoderma reesei / Isolation and functional analysis of the gene encoding a serine-threonine protein kinase that modulates the expression of genes regulated by carbohydrates Trichoderma reesei

Matheucci Junior, Euclides 09 November 2000 (has links)
O gene TrSNF1, homólogo aos membros da subfamília das proteínas serina-treonina quinases ativadas por AMP (AMPK) e relacionadas a SNF1, foi isolado do fungo filamentoso trichoderma reesei. A seqüência de aminoácidos putativa possui um domínio de quinase com 42% de identidade e 59% de similaridade com outras proteínas quinases da mesma subfamília. Em S. cerevisiae a SNFl é essencial para a expressão de genes reprimidos por glicose, em resposta a privação de glicose do meio de cultura. A expressão de TrSNFl em levedura mutante para SNF1, restaura a função de SNF1. A expressão de um antisense de TrSNFl em T. reesei causa um atraso na expressão do gene regulado por glicose, CBHI. Além disso, em experimento utilizando matrizes de DNA foi possível observar uma alteração da tendência global da expressão gênica entre a cepa selvagem e a cepa antisense. A observação da homologia estrutural com proteínas quinase da mesma subfamília, a similaridade funcional com SNFl de S. cerevisiae, e a alteração no padrão da expressão gênica in vivo, sugerem que TrSNFl pode estar envolvido na regulação do metabolismo de carboidratos em T. reesei. / A gene homologue to the members of the AMP-activated/SNFl protein kinase subfamily, TrSNF1, was isolated from the filamentous fungus Trichoderma reesei. The predicted protein of 692 amino acids has a kinase domain, that share 42 % identity and 59 % similarity to that of serine/threonine protein kinase of this family. In Saccharomyces cerevisiae, the SNFl protein kinase is required for expression of glucose repressed genes in response to withdrawal of glucose from the medium. Expression of the Trichoderma reesei SNF1-related sequence in yeast SNFl mutant restores SNFl function. The TrSNFl antisense expression in T. reesei causes a control alteration in the glucose-regulated gene CBHI. The observed structural identity with the AMP-activated/SNFl protein kinase subfamily, and the functional similarity to the yeast SNFl suggest that the TrSNFl may be involved in the regulation of sugar metabolism in Trichoderma reesei.
695

Avaliação da fração carboidratos solúveis em cana-de-açúcar para animais / The evaluation of sugarcane soluble carbohydrate fraction for animal feeding

Cabezas-Garcia, Edward Hernando 03 October 2011 (has links)
Objetivou-se com este estudo comparar diferentes métodos de determinação de carboidratos solúveis (CS) em cana-de-açúcar com o intuito de predizer valor nutritivo da forragem: conteúdo de sólidos solúveis (BRIX), conteúdo aparente de sacarose (POL), carboidratos não fibrosos (CNF), carboidratos solúveis em extrato aquoso (CSA) e carboidratos solúveis em extrato alcoólico (CSOH). Foram conduzidos dois experimentos envolvendo amostras da fração colmo e planta inteira. O primeiro avaliou o valor nutritivo da variedade IAC 86-2480 (terceiro corte) em resposta a dois métodos de colheita: colheita manual (MAN) e colheita mecânica (MEC) durante as fases de cultivo: 150, 180, 210, 240, 270, 300, 330 e 360 dias após colheita (DAC). As estimativas do CS, composição bromatológica (MS, CP, FDN, FDA, DIVMS e DIVMO), assim como da relação FDN/CS foram similares (P>0,05) entre os tratamentos, exceto para CSOH e FDN/CSOH para a fração colmo, e FDN/POL (P<0,05) para a planta inteira. O conteúdo de CS da planta inteira representou aproximadamente 80% do teor observado na fração colmo. Foram identificados três padrões de acúmulo de CS: a) POL e CSOH, b) BRIX, c) CNF. O modelo logístico não ajustou na predição de CSA. Até os 240 e 270 DAC, as relações entre FDN/BRIX e FDN/POL seguiram a mesma tendência para os métodos MAN e MEC respectivamente. Relações entre FDN/CS foram altamente correlacionadas com a digestibilidade da forragem, especialmente a relação FDN/CNF (r>0,8). A análise de componentes principais provou ser ferramenta útil para selecionar variáveis com o intuito de caracterizar valor alimentar em cana-de-açúcar. De acordo com o primeiro componente principal, o valor nutritivo é uma resposta de variáveis bromatológicas da fração fibrosa (ex. FDN, FDA), correspondendo a 54,4 e 64% da variância total da fração colmo e planta inteira respectivamente. No segundo experimento, foram avaliadas possíveis relações entre medidas morfológicas e químicas da planta visando explicar o acúmulo de CS e o valor nutricional da cana-de-açúcar (variedade IAC 93-3046), estabelecida sob dois níveis de adubação no plantio (NPK e NPK associada com esterco 120 kg N ha-1) ao longo da fase de maturação da planta em cana de primeiro corte. As amostras foram colhidas manualmente durante os períodos de 300, 360, 420 e 540 dias após plantio (DAP). Não houve efeito (P>0,05) da adubação na concentração de CS, a exceção das folhas secas (FS), CSA e minerais, na fração colmo. Três padrões de acúmulo de CS foram identificados nas duas frações morfológicas da planta: a) BRIX e CSOH; b) CNF E c) CSA. Embora POL não fosse considerada nesse experimento, as análises das curvas de CS (BRIX e CSOH) confirmaram que a cana atingiu a maturidade no mês de setembro como reportado na literatura. Regressões simples e múltiplas foram consideradas para predizer o acúmulo de CS, MS e o valor nutricional (digestibilidade). O modelo univariado apenas considerou variáveis químicas na predição, exceto para o teor de BRIX. Equações do tipo stepwise melhoraram o ajuste dos modelos (R2 e RQMR) ao considerar variáveis morfológicas, sendo a mais importante nas predições, o número de nós da fração colmo (NN). As equações para MS e CSA tiveram o menor poder de predição tanto nas regressões simples quanto nas múltiplas. A fração FDA foi a principal variável que explicou o valor nutritivo em amostras de cana-deaçúcar. / The objective of this research was to compare some potentialities of soluble carbohydrate (SC) methods currently used in sugarcane for animal feeding purposes: soluble solid content (BRIX), apparent sucrose content (POL), non fibrous carbohydrates (NFC), water soluble carbohydrates (WSC) and ethanol soluble carbohydrates (EtOH). Two trials involving stalk and whole plant sugarcane samples were conducted. The first trial evaluated the nutritive value of IAC 86-2480 variety (second growth) in response to two harvesting methods: manual (MAN) and mechanical (MEC) along of crop growing phase: 150, 180, 210, 240, 270, 300, 330 and 360 days after harvesting (DAH). The SC estimative, chemical composition (DM, CP, NDF, ADF, IVDDM and IVOMD) and NDF/SC relationships were similar (P>0.05) across treatments, except for EtOH and NDF/EtOH relationship at stalk and NDF/POL (P<0.05) at whole plant being MAN and MEC of those cases, respectively more advantageous for each. The whole plant SC content reached represents closer to 80% of total content observed in the stalk fraction. Were identified three typical SC accumulation patterns: a) POL and EtOH, b) BRIX, c) NFC. Until 240 (MAN) and 270 (MEC) DAH, the standardized NDF/BRIX and NDF/POL stalk relationships followed the same trend. NDF/SC relationships were highly correlated with forage digestibility, especially NDF/NFC (r > 0.8). Principal Component Analysis proved to be an useful tool to select variables in order to explain sugarcane feeding value. Therefore as described at the first principal component, the sugarcane feed value is in function of forage fibrous fraction (ex. NDF, ADF), corresponding to 54.4% (stalk) and 64.0% (whole plant) of total variance respectively. The second trial studied possible relationships established between both morphological as chemical plant measurements that could explain SC accumulation and feeding value of IAC 93- 3046 variety, under two levels of fertilisation at planting (NPK and NPK associated with cattle manure 120 kg N ha-1) along of ripening phase under plant crop conditions. Forage samples were collected manually at 300, 360, 420 and 540 days after planting (DAP). There was no effect (P>0.05) of fertilisation on SC dynamics, chemical composition and morphological crop variables, with the exception to dry leaves (DLEAF), water soluble carbohydrates (WSC) and minerals (ASH), in stalk fraction (P<0.05). The age of plant was the main factor responsible of the observed variability. Three SC patterns in sugarcane during this phase were identified: a) BRIX and EtOH, b) NFC e c) WSC. Although POL was not considered in this trial, the analysis of SC curves showed that BRIX and EtOH also reached to maturity in September conforming literature. Simple and multiple (stepwise) regressions were considered to predict SC, DM accumulation and feeding value (digestibility). The univariate models only considered chemical variables to prediction, except to BRIX. Stepwise equations have account also morphological crop variables to improve statistical prediction (R2, RMSE), being the most important: number of nodes (NN). Predictions of DM and WSC had the lowest power performed through simple and multiple equations. ADF fraction best fitted to feeding value prediction (IVDMD, IVOMD) in sugarcane samples.
696

Avaliação do potencial da casca de Eucalyptus spp. para a produção de bioetanol / Evaluation of the potential use of Eucalyptus spp. bark for bioethanol production

Bragatto, Juliano 19 November 2010 (has links)
A utilização de fontes renováveis para a produção de biocombustíveis tem sido incentivada no mundo todo. Assim, na proposta de um novo cenário energético mundial, aliado as condições ambientais, surge a necessidade de se procurar outras fontes alternativas de matéria primas renováveis. Neste contexto, o Brasil possui condições especiais, se considerarmos os resíduos lignocelulósicos do setor florestal. Atualmente, o Brasil é o maior produtor mundial de celulose à partir de fibra curta de Eucalyptus spp, com um setor bem desenvolvido e em plena expansão. Toda esta atividade industrial produz anualmente cerca de 2,8 a 5,7 milhões de toneladas resíduos sólidos na forma de casca (principalmente de eucaliptos). Em muitos casos o destino aplicado para essas biomassas é pouco eficiente e representa uma perda significativa do potencial energético, pois estes resíduos lignocelulósicos são passíveis de biotransformação a compostos com elevado valor agregado, tais como os biocombustíveis (etanol). Portanto, o objetivo deste trabalho foi avaliar o potencial das cascas de eucalipto frente a produção de etanol combustível. Desta maneira, as cascas de 5 clones comerciais (E.urophylla x E. grandis e E. grandis) foram caracterizadas quanto a composição química. As cascas de eucalipto foram submetidas a uma série de pré-tratamentos ácidos e alcalinos, avaliados em planejamento fatorial com o objetivo de recuperar os açúcares potencialmente fermentecíveis. As cascas de eucalipto apresentaram aproximadamente 20% de carboidratos solúveis totais CST (glicose, frutose e sacarose). Os CST foram extraídos com água quente à temperatura de 80oC e em seguida fermentados com leveduras convencionais (Saccharomyces cerevisiae). A produção de etanol por tonelada de casca seca foi de 106 litros (etanol de primeira geração). Após a extração dos CST, as biomassas residuais das cascas de eucalipto foram submetidas a uma série de pré-tratamentos. O pré-tratamento alcalino (NaOH) apresentou uma eficiência enzimática de conversão da glicose de aproximadamente 30% após 24 horas de incubação. Com os resultados obtidos da hidrólise enzimática, estima-se que possam ser produzidos mais 94 litros de etanol por tonelada de casca livre de extrativos (etanol celulósico). / The use of no fossil source for biofuels production has been stimuled in the all world. Proposing a new global scenario related to the energy matrix, together with the environmental conditions, there is the need to search alternative renewable raw materials. In this context, Brazil presents special conditions, considering the lignocellulosic residues from the forestry industry. Nowadays, Brazil is the largest cellulose short fiber producer from Eucalyptus spp, having a strong sector in expansion. This industrial activity produces in average 2,8 to 5,7 million tons of solid waste in the form of bark (mostly from eucalyptus). Usually, the destiny of this biomass is inefficient and represents a significant loss of the energetic potential, since these lignocellulosic residues can suffer biotransformation and produce high value components, like the biofuels (ethanol). Therewith, the aim of this work was to evaluate the potential of the eucalyptus bark related to ethanol fuel production. In this way, barks from 5 commercial clones (E. urophylla x E. grandis e E. grandis) were characterized due to the chemical composition. Eucalyptus barks were subjected to a series of acid and alkaline pretreatments, evaluated in factorial design aiming to recover potentially fermentable sugars. Eucalyptus bark presented on average 20% of total soluble carbohydrates TSC (glucose, fructose and sucrose). TSC were extracted with hot water (80 °C) and fermented by Saccharomyces cerevisiae. Ethanol production per ton of dry bark was 106 liters (first generation ethanol). After TSC extraction, the residual biomass from eucalyptus bark were subjected to several pretreatments. The alkaline pretreatment (NaOH) presented a high enzymatic efficiency of glucose conversion of approximately 30% after 24 hours of incubation. With the results obtained in enzymatic analysis, is estimated that it can be produced more than 94 liters of ethanol per ton of bark (cellulosic ethanol).
697

Auswirkung von Lichtakklimatisation und Saccharosedüngung auf Kohlenhydratgehalt und Vitalität von Ficus benjamina und Chamaedorea elegans

Haas, Manuela 17 January 2017 (has links)
Die Pflanzenqualität lässt sich durch Akklimatisationsmethoden gezielt beeinflussen. In der vorliegenden Arbeit wurden, speziell von Ficus benjamina und Chamaedorea elegans, die innere (Kohlenhydrate, Chlorophyll und Flavonole) und äußere Qualität (Morphologie, Habitus und Vitalität) im Kontext erfasst und interpretiert. Dazu wurde zunächst für beide Pflanzenarten eine neue Methode zur Bestimmung der Zuckergehalte (Glucose, Fructose, Saccharose) erarbeitet. Die Kultivierung der Pflanzen erfolgte in fünf aufeinanderfolgenden praxisüblichen Phasen der Wertschöpfungskette: Produktion, Lichtakklimatisation, Dunkeltransport, Regeneration und Innenraum. Diese simulierten Phasen zogen verschiedene Wachstumsbedingungen nach sich, die insbesondere den Wachstumsfaktor Licht betrafen und sich variantenbezogen unterschieden. Die Kohlenhydratgehalte sanken im Laufe der Wertschöpfungskette bei F. benjamina um 15 bis 30 % und bei Ch. elegans um 50 %. Es zeigte sich, dass Lichtintensitäten unter 350 µmol m-2 s-1 den Kohlenhydratgehalt negativ beeinflussten, dabei waren Unterschiede bei den Pflanzenarten zu beobachten. Darauf aufbauend wurden weitere Versuche durchgeführt, die eine exogene Zuckerapplikation (Konzentration 7,5 g l-1, 10 g l-1, 20 g l-1 Saccharose) über die Flüssigdüngung hinsichtlich der Wirkung auf den Kohlenhydratgehalt und die Vitalität der Pflanzen testeten. Auch hier unterschieden sich die geprüften Pflanzenarten in ihrer Reaktion. Vor allem für Chamaedorea elegans erwies sich eine Zuckerdüngung als vorteilhaft. Die vorliegende Arbeit liefert für Wissenschaft und Praxis eine umfassende und aktuelle Übersicht über die Möglichkeiten und Grenzen zur Beeinflussung der Pflanzenqualität und -vitalität mittels Lichtakklimatisation und Zuckerdüngung. Erstmalig wurde die Entwicklung der Kohlenhydratgehalte über einen längeren Untersuchungszeitraum, mit Blick auf die zentralen Kultivierungsphasen, für beide Innenraumbegrünungspflanzen aufgezeigt. / Plant quality can be influenced by acclimatisation. Most of the previous studies on plants for interior landscaping focused mainly on external quality. Therefore, this thesis presents the results of a study on Ficus benjamina and Chamaedorea elegans, investigating and analysing primarily inner quality characteristics (carbohydrates, chlorophyll, and flavonols). However, external quality characteristics (morphology, habitus, and vitality) were considered as well. In a first step, a new method was developed to determine the sugar content (fructose, glucose, sucrose) for both species. Cultivation of F. benjamina and Ch. elegans plants was carried out in five consecutive steps following standard practice of the value chain: production, light acclimatisation, transport in darkness, regeneration and interior spaces. These phases simulated different cultivation conditions, particularly varying light treatments. During the value chain the carbohydrate content (sugar and starch) in F. benjamina decreased 15 to 30 % and in Ch. elegans about 50 %. Light intensities below 350 µmol m 2 s-1 diminished carbohydrate concentrations depending on the plant species investigated. Based on these findings additional experiments were undertaken testing sugar supplied via the nutrient solution (7.5 g l-1, 10 g l-1 and 20 g l-1 sucrose). Both species investigated responded with different carbohydrate concentration and vitality. Sugar nutrition was particularly beneficial for Ch. elegans. This work provides a comprehensive and current overview of the capabilities and limitations to influence plant quality and vitality by light acclimatisation and sugar nutrition. For the first time, carbohydrate dynamics in interior plants has been studied in long term experiments in relation to their key cultivation stages for two important model species.
698

Einfluss eines differenzierten Wasserangebotes auf Wurzelwachstum und Reservekohlenhydrathaushalt von Bleichspargel (Asparagus officinalis L.)

Weinheimer, Sebastian 17 June 2008 (has links)
Durch den in den letzten Jahren in Deutschland stark ausgeweiteten Spargelanbau wird der Kostendruck auf die Erzeuger immer größer. Um eine Spargelfläche ökonomisch erfolgreich zu bewirtschaften sind Anbauempfehlungen die auf einer objektiven Grundlage beruhen unersetzlich. Eine Möglichkeit hierzu ist das Messen der Reservekohlenhydratkonzentration (RKH-Konzentration) in den Speicherwurzeln. Ein sehr großer Nachteil dieser Methode ist, dass die Speicherwurzelmasse, die einen erheblichen Einfluss auf die verfügbare Gesamtmenge an Reservekohlenhydraten hat unberücksichtigt bleibt. Hinsichtlich der Wurzelmasse und der Wurzelverteilung im Boden bestanden bislang große Wissenslücken. Um den Einfluss der Bewässerung auf die Wurzelmasse und die Wurzelverteilung zu ermitteln, wurde ein Praxisversuch angelegt. Zu bestimmten Zeitpunkten in der Vegetationsperiode wurden Proben auf einer bewässerten und einer unbewässerten Variante entnommen. In der bewässerten Variante waren zu jedem Zeitpunkt signifikant mehr Speicherwurzeln vorhanden. Auch die Speicherwurzelfrischmasse war signifikant größer. In der Tiefenverteilung unterschieden sich jedoch die Varianten nicht. Auch in Gefäßversuchen konnten diese Ergebnisse bestätigt werden. Die Faserwurzelverteilung unter Praxisbedingungen unterschied sich jedoch erheblich von der Speicherwurzelverteilung. In der bewässerten Variante war der Boden im untersuchten Profil komplett mit Faserwurzeln durchwachsen, während in der unbewässerten Variante die Faserwurzeln lediglich in den oberen Bodenschichten zu finden waren. In Gefäßversuchen durchwurzelten die Faserwurzeln unabhängig von der Bewässerungssteuerung das gesamte Bodenvolumen. Unter mehrjährigen Praxisbedingungen lag die RKH-Konzentration in der unbewässerten Variante immer über der Konzentration in der bewässerten Variante. Die Gesamtmenge an RKH lag jedoch aufgrund der größeren Speicherwurzelmasse in der bewässerten Variante höher. Daher muss bei der Verwendung der RKH-Methode als Steuerinstrument im Spargelanbau unbedingt auch die Speicherwurzelmasse berücksichtigt werden. / The cultivation of asparagus in Germany has strongly expanded over the last years. Hence the cost pressure is increasing vastly on the producers. For the cultivation of asparagus, impartial cultivation recommendations are necessary. One possibility is measuring the carbohydrate concentration (CHO-concentration) in the storage roots. A great disadvantage of this method is that the root mass, which has a substantial influence on the total quantity of available carbohydrates, remains unconsidered. Regarding to the root mass and the distribution of roots in the soil so far large gaps in the grower’s knowledge are existent. In order to determine the influence of the irrigation on the root mass and the distribution of roots, a trial was prepared. Samples of a watered and an unwatered variant were taken at certain points in the vegetation period. In the watered variant were significantly more storage roots were present at each time. Further the storage root fresh mass was significantly bigger. However, in the vertical distribution the variants did not differ, which could also be confirmed in container trials. The distribution of fibre roots under practical conditions did indeed differ substantially from the storage root distribution. In the watered variant the soil profile was completely filled with fibre roots, whereas in the unwatered variant the fibre roots were only found in the upper soil layer. In container trials the fibre roots were distributed throughout the entire soil volume independently of the irrigation control. Under practical conditions the CHO concentration was always higher for the unwatered variant compared to the watered variant. However, the total quantity of CHO was higher in the watered variant due to the larger storage root mass. Therefore the storage root mass has to be considered when using the CHO method as an instrument in the cultivation of asparagus.
699

Impacto de ingrediente funcional sobre a saúde intestinal / Impact of functional ingredient on intestinal health

Souza, Gabriela Santos 20 May 2014 (has links)
O microbioma intestinal influencia de maneira positiva e/ou negativa o bem estar e o equilíbrio da saúde no organismo humano. Carboidratos não disponíveis, tais como frutanos e amido resistente (encontrado na farinha de banana verde), são ingredientes funcionais que resistem à digestão, estimulam o peristaltismo e o trânsito intestinal, e podem aumentar população de bactérias benéficas. O presente estudo teve como objetivo avaliar o impacto do consumo regular e descontinuado (durante 6 semanas e 3 vezes por semana) de sopas adicionadas de inulina (8 g) ou farinha de banana verde (FBV) (8 g), sobre o funcionamento intestinal em voluntários saudáveis. Para a avaliação do funcionamento intestinal, o questionário semanal Gastrointestinal Symptom Rating Scale foi validado para o idioma português (Brasil), apresentando alfa de Cronbach de 0,82 e correlação intraclasse de 0,83. Além desta ferramenta, também foi utilizado um questionário diário de hábito gastrintestinal, que inclui a Escala de Bristol. Após o consumo das sopas adicionadas de inulina, os voluntários apresentaram redução na consistência das fezes, aumento na frequência de evacuações e na necessidade de evacuar, entretanto foi observado aumento leve de flatulência. O grupo que consumiu sopas adicionadas com FBV apresentou redução na consistência das fezes, no tempo de trânsito intestinal, nas dores abdominais e na sensação de esvaziamento incompleto do intestino, e aumento na frequência diária de evacuações. Dessa forma, estes carboidratos não disponíveis, na frequência e período de consumo estudados, podem melhorar o funcionamento intestinal, sem causar efeitos de desconforto gastrintestinal / The intestinal microbiome can positively and / or negatively influence both well-being and health balance in the human body. Unavailable carbohydrates, such as fructans and resistant starch (present in unripe banana flour) are functional ingredients that resist digestion, stimulate peristalsis and intestinal transit, and may increase the population of beneficial bacteria. The present study aimed to assess the impact of regular and discontinued consumption (for 6 weeks and 3 times per week) of soups added inulin (8 g) or unripe banana flour (UBF) (8 g), on intestinal function of healthy volunteers. For the evaluation of intestinal function, the weekly questionnaire Gastrointestinal Symptom Rating Scale was validated to Portuguese (Brazil), with Cronbach\'s alpha 0.82 and intraclass correlation 0.83. Besides this tool, a daily questionnaire of gastrointestinal habits was also used, which included the Bristol Stool Form Scale. After consumption of soups added inulin, the volunteers presented a reduction on stool consistency, increased frequency of bowel movements and evacuating need, however slightly increased flatulence was observed. The group that consumed soup added UBF presented a decrease in stool consistency, intestinal transit time, abdominal pain and sensation of incomplete bowel emptying, and an increase in the frequency of bowel movements. Therefore, these unavailable carbohydrates, when consumed in the frequency and period of the present study, can improve bowel function without causing any gastrointestinal discomfort
700

Organokatalysierte, kettenverlängernde Kaskadenreaktionen an ungeschützten Kohlenhydraten

Voigt, Benjamin 28 April 2016 (has links)
Im Rahmen der vorliegenden Dissertation wurden drei neue Zugangswege zu kettenverlängerten Kohlenhydraten aus ungeschützten Aldosen entwickelt. Dabei ermöglichen diese Protokolle die Synthese verschiedener Klassen von kettenverlängerten Strukturen. Neben der selektiven Darstellung von 2-Ketoaldonsäurederivaten konnten effiziente Zugangsstrategien zu hoch funktionalisierten bizyklischen C-Glycosiden und polyhydroxylierten Pseudopeptiden präsentiert werden. Dabei konnte gezeigt werden, dass ein breites Spektrum dieser verschiedenen Arten kettenverlängerter Kohlenhydrate aus ungeschützten natürlichen Hexose- und Pentose-Substraten zugänglich ist. Durch den Einbezug der natürlich vorhandenen Hydroxylgruppen der Aldosen ermöglichen die präsentierten Kaskadenreaktionen einen sehr effektiven Zugang zu hoch funktionalisierten Produkten, welche in Sequenzen unter Verwendung von Schützungsstrategien nur in aufwendigen, mehrstufigen Reaktionen zugänglich wären. Zudem konnte gezeigt werden, dass die natürlich vorkommende Chiralität in den verwendeten Substraten für ein stereoselektives Dirigieren der neu installierten Stereozentren nutzbar ist. Damit konnte eine bedeutende Erweiterung des bestehenden Repertoires von Methoden für die Verlängerung ungeschützter Kohlenhydrate erreicht werden.. Die entwickelten Transformationen bestechen durch ihre hohe Atomökonomie, wie auch durch ihre sehr gute ökologische und ökonomische Bilanz und erfüllen damit die Anforderungen an nachhaltige Synthesemethoden. / The scope of the presented work was the investigation of new organocatalysed synthesis strategies of carbon chain elongated carbohydrates. Here three new accesses to three different structure motifs of these biologically highly important and manifold compounds from unprotected carbohydrates were developed. Using naturally occurring, unprotected pentoses and hexoses, a wide variety of keto aldonic acids, bicyclic C-glycosides and glycosylated pseudopeptides are accessible in three different cascade reactions. All of the presented strategies enable the C-chain elongation by employment of the naturally occurring aldehyde motive without tedious protection ad deprotection protocols or synthetic modifications of the substrates. By utilisation of the chiral hydroxyl moieties of the carbohydrate chain, diastereoselective control of the installation of the stereocenters formed in the cascade reactions is achieved. The high regio- and diastereoselectivities, high yields as well as the convenient synthesis conditions of the presented protocols make the presented cascade reactions valuable tools among the already described accesses to the biological important compounds of chain elongated carbohydrates. The presented cascades enable the diastereoselective synthesis of a high variety of these motifs in only one synthetic step from readily available unprotected carbohydrates without additional modification steps. These advantages give rise to a very high atom economy of the transformations, which therefore fulfil the requirements to green chemistry and sustainable synthesis methods.

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