Orientador: Rubens Maciel Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-08-13T23:08:44Z (GMT). No. of bitstreams: 1 Polowski_NataschaVigdis_D.pdf: 3937033 bytes, checksum: 67463e72c2fe6b2c2bf718ee1aefe5cd (MD5) Previous issue date: 2009 / Resumo: Neste trabalho foram desenvolvidos três modelos para predição de Número Kappa (Modelo Determinístico, Modelo Neural e Modelo Híbrido). O Modelo determinístico inclui transferência de massa e reações cinéticas intrínsecas baseadas em reações paralelas de lignina, celulose e hemicelulose. Este divide o processo de deslignificação em 3 estágios ou fases, sendo que as 3 fases correspondem a 3 diferentes tipos de lignina (inicial, principal e residual). O modelo é específico para polpa de eucalipto (fibra curta) e digestor batelada. Umas das contribuições para este modelo proposto foram às inclusões de reações para lignina, hemicelulose e celulose total, carboidratos, além do Número Kappa. Para Modelo Determinístico foram utilizados dados experimentais coletados no RAIZ - Instituto de Investigação da Floresta e Papel e dados gerados pelas simulações. As variáveis operacionais utilizadas como dados de entrada foram: espessura, temperatura inicial, álcali efetivo, relação licor madeira, tempo de cozimento, densidade e porosidade. O Modelo Determinístico também foi desenvolvido para digestor contínuo e foi validado com dados industriais para fibra curta de eucalipto. A modelagem feita para um digestor batelada é a mesma que para um digestor contínuo, sendo que no contínuo existem de 3 a 4 etapas dentro do equipamento. Por conseguinte, o digestor contínuo é modelado como se fosse um batelada só que fracionadamente (temperaturas e tempos para cada estágio do equipamento e de forma seqüencial). Neste trabalho foi empregado um método de otimização (Programação Quadrática Sucessiva) para definir o procedimento de operação no digestor contínuo permitisse a obtenção do produto (polpa) com teores inferiores a 1,5 % de lignina residual. Industrialmente este valor está em torno de 3 % de lignina residual. O Modelo Neural proposto é do tipo "feedforward" e com treinamento por retropropagação. Para este modelo as variáveis de entrada (inputs) foram temperatura, álcali efetivo e Fator H. A variável de saída (output) é o Número Kappa. A quantidade de neurônios ocultos foi definida pelo modelo neural que apresentou o menor erro para o conjunto de validação e treinamento. O número de interações também foi definido a partir do menor erro gerado pelas simulações. Este modelo foi validado com dados industriais e experimentais. O Modelo Híbrido utilizou como variáveis de entrada Kappa Neural e Teórico, temperatura e Fator H e a variável de saída é o Número Kappa Híbrido. Este foi validado com dados industriais. Os modelos apresentados (Determinístico, Neural e Híbrido) são ferramentas úteis para as fábricas de celulose e papel, uma vez que existe a possibilidade de serem aplicados para simulação de processos, otimização e controle. Os modelos podem ser testados para diferentes condições operacionais sem alterar a produção. Além de possibilitarem melhor controle de algumas variáveis no processo fabril, isto, sem perda de qualidade do produto. Neste estudo a rede neural e os modelos cinéticos apresentaram resultados equivalentes. Palavras-chaves: Número Kappa, Modelo Determinístico, Modelo Neural e Modelo Híbrido / Abstract: In this work three models were developed for prediction of Kappa number (Deterministic Model, Neural and Hybrid Model). The Deterministic Model includes mass transfer and reaction kinetics based on intrinsic parallel reactions of lignin, cellulose and hemicellulose. This divides the process of Delignification in 3 stages or phases, with the 3 phases correspond to 3 different types of lignin (initial, bulk and residual). The model is specific to the eucalyptus pulp (short fiber) and batch digester. One of the contributions to this proposed model were the inclusion of reactions for lignin, cellulose and hemicellulose total, carbohydrates, than the Kappa number. Deterministic model was used for experimental data collected in the RAIZ - Instituto de Investigação da Floresta e Papel and data generated by simulations. The operating variables used as input data were: thickness, initial temperature, effective alkali, liquor ratio wood, the cooking time, density and porosity. The Deterministic Model was developed for continuous digester, and was validated with industrial data for short fiber eucalyptus. The modeling done for a batch digester is the same as for a continuous digester, which are continuous in 3 to 4 steps inside the equipment. Wherefore the continuous digester is modeled as a single batch that fractionation (temperatures and times for each stage of the equipment and sequential manner). This study employed a method of optimization (Successive Quadratic Programming) to define the procedure for operation in continuous digester allowed to obtain the product (pulp) with levels below 1.5% of residual lignin. Industrially this value is around 3% of residual lignin. The Neural Model is proposed as "feedforward" and training by backpropagation. For this model the input variables were temperature, effective alkali and H-Factor. The variable output is the Kappa number. The number of hidden neurons was defined by the neural model that showed the smallest error for the set of validation and training. The number of interactions was also determined from the smallest error generated by simulations. This model was validated with experimental and industrial data. The hybrid model used as input variables and Kappa Neural theoretical, temperature, and factor H and the output variable is the number Kappa Hybrid. This was validated with industrial data. The models presented (deterministic, Neural and Hybrid) are useful tools for the manufacture of pulp and paper, since there is the possibility to be applied to simulation of processes, optimization and control. The models can be tested for different operating conditions without changing the output. Besides, allowing better control of some variables in the manufacturing process, ie without loss of quality of product. In this study, the neural network and the kinetic models showed similar results. Keywords: Kappa number, Deterministic Model, Neural Model and Hybrid Model / Doutorado / Desenvolvimento de Processos Químicos / Doutor em Engenharia Química

O setor sucroalcooleiro é uma importante representação do potencial bioenergético do Brasil. A estimativa da produção de cana-de-açúcar para a safra de 2007/2008, segundo a Companhia Nacional de Abastecimento (Conab), será de mais de 11% que na safra passada. A cana-de-açúcar constitui uma fonte de energia abundante e renovável. Além do aproveitamento de seu caldo para a produção de etanol e do emprego do bagaço para fins energéticos em processos de combustão e gaseificação, seus polissacarídeos constituintes (celulose e polioses) podem ser liberados por hidrólises enzimáticas para serem fermentados a etanol e outros produtos químicos de maior valor agregado. Porém os resíduos gerados a partir desse processamento, como o bagaço e a vinhaça, podem ser reaproveitados para outros fins. A ecologia da degradação da celulose e lignina é lenta e muito complexa, envolvendo inúmeras e variadas interações metabólicas entre diferentes microrganismos que também são afetados por vários fatores ambientais. Partindo de nove linhagens de fungos, foram selecionados quatro quanto à produção de biomassa e produção de celulases e ligninases em meios específicos. Estas linhagens, três espécies e Pleurotus: P. sajor-caju, P. ostreatoroseus e P. ostreatus, e Trichoderma reesei foram cultivadas em bagaço pré-tratado com 2% H2SO4, 1,5% NaOH, 2% H2O2 e combinação 2% H2O2 + 1,5% NaOH. Foram determinados o teor de celulose, lignina e hemicelulose resultante de cada tratamento e a atividade lignolíticas: lacase, peroxidase e manganês peroxidase e a atividade das enzimas celulolíticas: exoglicanase e endoglicanase, comparando com um controle sem tratamento químico. A atividade celulolítica foi avaliada com os quatro fungos cultivados em meio bagaço-moído umedecido com vinhaça e bagaço-moído umedecido com meio mineral. Em relação ao controle foi observado que o pré-tratamento conjunto 2% H2O2 + 1,5% NaOH + autoclave proporcionou maior quebra nas fibras aumentando 1,4 vezes o teor de celulose e diminuindo em 8,5 vezes o da hemicelulose. Esse mesmo tratamento também proporcionou uma maior atividade lignolítica para as quatro linhagens. O ascomiceto T. reesei produziu lacase, peroxidase e manganês peroxidase em todos os tratamentos inclusive no controle, sendo a atividade de manganês peroxidase de 1,9 a 4,8 vezes maior que os basidiomicetos. / The sugar-alcohol industry is an important representation of the bioenergy potential of Brazil. The estimative for the 2007/2008 sugarcane production, according to the National Supply Company (Conab), will be of about 11% more than the last season. Sugarcane constitutes a large and renewable energy source. Besides the exploitation of its juice for ethanol production and the use of bagasse for energetic means in processes of combustion and gasification, its polysaccharides constituents (cellulose and cellobiose) can be released by enzymatic hydrolyses for alcohol fermentation and other chemical of higher aggregate value. However the residues generated from this process, like bagasse and vinasse, which can be reutilized for other means. To obtain an effective conversion of these residues, chemical and biological pre-treatments are necessary for an improved hydrolysis. The ecology of the cellulose and lignin degradation is slow and very complex, involving innumerous and different metabolic interactions among microorganism that are also affected by many environmental factors. From nine lineages of fungi, were selected four relating to the production of biomass and cellulases and ligninases in specific media. These lineages, three species of Pleurotus: P. sajor-caju, P. ostreatoroseus and P. ostreatus, and the ascomycete Trichoderma reesei were cultivated in pre-treated bagasse with 2% H2SO4, 1,5% NaOH, 2% H2O2 and a combination of 2% H2O2 + 1,5% NaOH. It was determined the levels of cellulose, lignin and hemicellulose from each treatment and the lignolytic activity: laccase, peroxidase and manganese peroxidase and the activity of the cellulolitic enzymes: exogluconase and endogluconase, comparing to a control without chemical treatment. The cellulolitic activity was evaluated with the four cultivated fungi in two media: a grounded bagasse + vinasse and grounded bagasse + mineral media. Relating to the control was observed that the pre-treatment in conjunction with 2% H2O2 + 1,5% NaOH + autoclave promoted more breakage in the fiber increasing to 1,4 times the level of cellulose and decreasing the levels of hemicellulose to 8,5 times. This same treatment promoted a higher lignolytic activity for the four lineages. The ascomycete T. reesei produced laccase, peroxidase and manganese peroxidase in all treatments including the control, having the manganese peroxidase activity ranging from 1,9 to 4,8 times higher than the basidiomycetes.

Orientador: Gonçalo Amarante Guimarães Pereira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-24T16:05:35Z (GMT). No. of bitstreams: 1 Temer_Beatriz_M.pdf: 9784134 bytes, checksum: 1bdd018cb932c19745ec5d68cf0f0755 (MD5) Previous issue date: 2014 / Resumo: Um dos principais desafios a serem superados para que a produção de etanol lignocelulósico seja viável é a obtenção de um micro-organismo capaz de fermentar pentoses e hexoses de maneira eficiente. A levedura Saccharomyces cerevisiae é o principal micro-organismo utilizado nas fermentações industriais, devido à sua alta eficiência no consumo de glicose e tolerância às altas concentrações de etanol. Entretanto, linhagens selvagens dessa levedura não são capazes de consumir pentoses naturalmente. Desta maneira, a expressão heteróloga de genes que possibilitem o consumo de pentoses em S. cerevisiae é uma abordagem interessante que vem sendo desenvolvida por diversos grupos de pesquisa. A xilose é o açúcar de cinco carbonos presente em maior porcentagem nos materiais lignocelulósicos e é consumida pelos organismos através de duas vias principais, a via da xilose isomerase (XI) e a via oxi-redutiva. A bactéria Propionibacterium acidipropionici, industrialmente interessante por produzir ácido propiônico, foi estudada neste trabalho com relação à sua capacidade de consumir xilose. A partir dos ensaios de fermentação realizados, foi possível comprovar que ela é capaz de consumir este açúcar na msma proporção que a glicose. A análise de dados genômicos de P. acidipropionici indicou que a via da XI é a utilizada para o consumo de xilose. Assim, o gene xylA, que codifica a XI de P. acidipropionici, foi expresso em uma linhagem industrial de S. cerevisiae. Após a realização de testes fermentativos foi possível constatar que a linhagem construída não apresentou consumo de xilose. Apesar da expressão do gene xylA ser comprovada, não foi possível detectar atividade enzimática da XI, resultados que fornecem indícios de que a proteína pode não estar sendo sintetizada ou, caso esteja sendo sintetizada, não é funcional. Mais de 36 XIs provenientes de organismos diferentes já foram expressas em S. cerevisiae, dentre essas apenas 12 foram funcionalmente expressas. As causas da não funcionalidade na maioria das tentativas de expressão heteróloga das XIs são desconhecidas. Entretanto, alguns trabalhos afirmam que esse fenômeno pode estar relacionado ao enovelamento incorreto da xilose isomerase em S. cerevisiae. Desta forma, a expressão de genes que codificam chaperonas específicas é uma estratégia promissora para a obtenção de uma xilose isomerase funcional / Abstract: One of the main challenges to be overcome to enable the production of lignocellulosic ethanol is the development of a microorganism capable of fermenting pentoses and hexoses efficiently. Currently the yeast Saccharomyces cerevisiae is the main microorganism used in industrial fermentations due to its high efficiency in glucose uptake and tolerance to high concentrations of ethanol; however, it is not able to consume pentoses naturally. Thus the heterologous expression of genes that allow the pentose consumption in S. cerevisiae is an interesting approach that has been developed by several research groups. Xylose is the main component in lignocellulosic biomass, and is consumed by organisms through two main pathways, the xylose isomerase (XI) pathway and the oxy-reductive pathway. The bacterium Propionibacterium acidipropionici is industrially interesting for its production of propionic acid, and was studied in this work with respect to its ability to consume xylose. Fermentation assays conducted proved that these bacteria can consume xylose in the same proportion as glucose. The analysis of genomic data from P. acidipropionici indicated that the XI pathway is used to ferment xylose, in this manner the xylA gene encoding this species XI was expressed in an industrial strain of S. cerevisiae. After conducting fermentation tests it was found that the strain developed was not able to consume xylose even though the XI gene was expressed in the yeast. Moreover, it was not possible to detect enzymatic activity of XI, indicating that the protein is probably not being synthesized or it is not functional. Over 36 XIs from different organisms have been expressed in S. cerevisiae, among these only 12 were functionally expressed. The causes of non-functionality in most attempts at heterologous expression of the XIs are unknown, however, some studies claim that this event may be related to the absence of chaperones, which assist the correct folding of proteins. Thus the expression of genes that encode specific chaperone is a promising strategy to obtain functional expression of these XIs / Mestrado / Genetica de Microorganismos / Mestra em Genética e Biologia Molecular

Studies into sources of alternative liquid transport fuel energy have identified agro-industrial wastes, which are lignocellulosic in nature, as a potential feedstock for biofuel production against the background of depleting nonrenewable fossil fuels. In South Africa, large quantities of apple and other fruit wastes, called pomace, are generated from fruit and juice industries. Apple pomace is a rich source of cellulose, pectin and hemicellulose, making it a potential target for utilisation as a lignocellulosic feedstock for biofuel and biorefinery chemical production. Lignocellulosic biomass is recalcitrant in nature and therefore its degradation requires the synergistic action of a number of enzymes such as cellulases, hemicellulases, pectinases and ligninases. Commercial enzyme cocktails, containing some of these enzymes, are available and can be used for apple pomace degradation. In this study, the degradation of apple pomace using commercial enzyme cocktails was investigated. The main focus was the optimisation of the release of sugar monomers that could potentially be used for biofuel and biorefinery chemical production. There is no or little information reported in literature on the enzymatic degradation of fruit waste using commercial enzyme mixtures. This study first focused on the characterisation of the substrate (apple pomace) and the commercial enzyme cocktails. Apple pomace was found to contain mainly glucose, galacturonic acid, arabinose, galactose, lignin and low amounts of xylose and fructose. Three commercial enzyme cocktails were initially selected: Biocip Membrane, Viscozyme L (from Aspergillus aculeatus) and Celluclast 1.5L (a Trichoderma reesei ATCC 26921 cellulase preparation). The selection of the enzymes was based on activities declared by the manufacturers, cost and local availability. The enzymes were screened based on their synergistic cooperation in the degradation of apple pomace and the main enzymes present in each cocktail. Viscozyme L and Celluclast 1.5L, in a 50:50 ratio, resulted in the best degree of synergy (1.6) compared to any other combination. The enzyme ratios were determined on Viscozyme L and Celluclast 1.5L based on the protein ratio. Enzyme activity was determined as glucose equivalents using the dinitrosalicylic acid (DNS) method. Sugar monomers were determined using Megazyme assay kits. There is limited information available on the enzymes present in the commercial enzyme cocktails. Therefore, the main enzymes present in Viscozyme L and Celluclast 1.5L were identified using different substrates, each targeted for a specific enzyme and activity. Characterisation of the enzyme mixtures revealed a large number of enzymes required for apple pomace degradation and these included cellulases, pectinases, xylanases, arabinases and mannanases in different proportions. Viscozyme L contained mainly pectinases and hemicellulases, while Celluclast 1.5L displayed largely cellulase and xylanase activity, hence the high degree of synergy reported. The temperature optimum was 50ºC for both enzyme mixtures and pH optima were observed at pH 5.0 and pH 3.0 for Viscozyme L and Celluclast 1.5L, respectively. At 37ºC and pH 5.0, the enzymes retained more that 90% activity after 15 days of incubation, allowing the enzymes to be used together with less energy input. The enzymes were further characterised by determining the effect of various compounds, such as alcohols, sugars, phenolic compounds and metal ions at various concentrations on the activity of the enzymes during apple pomace hydrolysis. Apart from lignin, which had almost no effect on enzyme activity, all the compounds caused inhibition of the enzymes to varying degrees. The most inhibitory compounds were some organic acids and metal ions, as well as cellobiose and xylobiose. Using the best ratio for Viscozyme L and Celluclast 1.5L (50:50) for the hydrolysis of apple pomace, it was observed that synergy was highest at the initial stages of hydrolysis and decreased over time, though the sugar concentration increased. The type of synergy for optimal apple pomace hydrolysis was found to be simultaneous. There was no synergy observed between Viscozyme L and Celluclast 1.5L with ligninases - laccase, lignin peroxidase and manganese peroxidase. Hydrolysing apple pomace with ligninases prior to addition of Viscozyme L and Celluclast 1.5L did not improve degradation of the substrate. Immobilisation of the enzyme mixtures on different supports was performed with the aim of increasing stability and enabling reuse of the enzymes. Immobilisation methods were selected based on the chemical properties of the supports, availability, cost and applicability on heterogeneous and insoluble substrate like apple pomace. These methods included crosslinked enzyme aggregates (CLEAs), immobilisation on various supports such as nylon mesh, nylon beads, sodium alginate beads, chitin and silica gel beads. The immobilisation strategies were unsuccessful, mainly due to the low percentage of immobilisation of the enzyme on the matrix and loss of activity of the immobilised enzyme. Free enzymes were therefore used for the remainder of the study. Hydrolysis conditions for apple pomace degradation were optimised using different temperatures and buffer systems in 1 L volumes mixed with compressed air. Hydrolysis at room temperature, using an unbuffered system, gave a better performance as compared to a buffered system. Reactors operated in batch mode performed better (4.2 g/L (75% yield) glucose and 16.8 g/L (75%) reducing sugar) than fed-batch reactors (3.2 g/L (66%) glucose and 14.6 g/L (72.7% yield) reducing sugar) over 100 h using Viscozyme L and Celluclast 1.5L. Supplementation of β- glucosidase activity in Viscozyme L and Celluclast 1.5L with Novozyme 188 resulted in a doubling of the amount of glucose released. The main products released from apple pomace hydrolysis were galacturonic acid, glucose and arabinose and low amounts of galactose and xylose. These products are potential raw materials for biofuel and biorefinery chemical production. An artificial neural network (ANN) model was successfully developed and used for predicting the optimum conditions for apple pomace hydrolysis using Celluclast 1.5L, Viscozyme L and Novozyme 188. Four main conditions that affect apple pomace hydrolysis were selected, namely temperature, initial pH, enzyme loading and substrate loading, which were taken as inputs. The glucose and reducing sugars released as a result of each treatment and their combinations were taken as outputs for 1–100 h. An ANN with 20, 20 and 6 neurons in the first, second and third hidden layers, respectively, was constructed. The performance and predictive ability of the ANN was good, with a R² of 0.99 and a small mean square error (MSE). New data was successfully predicted and simulated. Optimal hydrolysis conditions predicted by ANN for apple pomace hydrolysis were at 30% substrate (wet w/v) and an enzyme loading of 0.5 mg/g and 0.2 mg/mL of substrate for glucose and reducing sugar, respectively, giving sugar concentrations of 6.5 mg/mL and 28.9 mg/mL for glucose and reducing sugar, respectively. ANN showed that enzyme and substrate loadings were the most important factors for the hydrolysis of apple pomace.

For complete degradation of hemicellulose into its monomers from lignocellulose biomass, the synergistic action of a broad range of hydrolytic enzymes is needed. Therefore, production of enzymes from their natural producer is desirable. To obtain a powerful b-1,4-endoxylanase producing fungus, 304 environmental samples were collected from various locations in Singapore, leading to 603 isolates. Among them, 71 exhibiting b-1,4-endoxylanase activity were identified belonging mainly to the genera of Aspergillus, Penicillium, and Trichoderma. Further analysis revealed Aspergillus niger DSM 26641 as a potential and stable b-1,4-endoxylanase producer, being able to grow in hydrothermal lignocellulose hydrolysate exhibiting its maximal b-1,4-endoxylanase activity at pH 4 and 60◦C. This strain is thought to be very suitable for lactic acid production in a simultaneous saccharification and fermentation at pH values below 5.

No description available.

Lignin is one of the most abundant natural polymers on Earth, and a valuable resource. Despite being widely available, only a small amount of the produced lignin is currently utilized to make high-value goods, with the majority being used for pulp mills to recover energy. However, the possibility to convert lignin into commercially viable products is presented by the rising need for sustainable and renewable resources. In the past, research has mostly concentrated on converting lignin into chemicals, materials, and biofuels; nevertheless, there has not been much advancement in practical applications. Lignin is difficult to depolymerize due to its intricate structure and resistance to degradation. To separate lignin from lignocellulosic biomass, a number of techniques have been developed, such as kraft and sulfite pulping. These techniques, though, result in lignin with various characteristics. As a result, improved lignin isolation methods are required in order to produce high-quality, pure lignin. Due to its capacity to solubilize lignocellulosic biomass and extract lignin, ionic liquid-based lignin isolation has attracted interest. Ionic liquids are environmentally friendly since they may be recycled and used again. There are still issues with toxicity, physicochemical data, and industrial-scale recovery, though. Lixea is a startup company that specializes in sustainable technology, especially lignin. They have created a novel method of fractionating lignocellulose known as Dendronic® that uses inexpensive ionic liquids to separate lignin and cellulose from biomass. Potentially, this process could result in renewable products, such as chemicals and biofuels on a large scale. Filtration of the lignin is one of the main bottlenecks operations at Lixea`s pilot plan. In this paper two different strategies; Maturing of the lignin suspension through temperature cycling and using previously isolated lignin filter cake as precipitation and filtration aid, have been tested out at the lab scale to improve the lignin filtration speed. Based on the observations in this work the heat treatment strategy is the most promising one, therefore it is recommended to test it the pilot plant to confirm the lab-scale experiments and improve the plant operation. Overall, further research and development are needed to unlock the full potential of lignin as a flexible and sustainable resource.

Mycelium-based composite (MBC) is being developed and researched in multiple commercial markets as an alternative sustainable material. MBC utilizes the mycelium ability to create a web-like structure in lignocellulosic structures. However, producing the material in a natural environment and subjecting it to various tests; the study aims to examine the distress of the southern Swedish climate on MBC grown in different substrates. The selection of substrates are based on their compatibility to fungal growth, the substrates are also locally sourced and grown. This is to explore MBC material production with a focus on circular economy as biodegradable material in architecture could help develop a reuse and recycle system. Various tests were done on the different substrate MBC to determine its characteristics, limitations and opportunities. The tests were developed with a focus on architectural construction and the southern Swedish climate; meaning experiments including MBC reaction to fire, water and temperatures. The results are based on the different MBC materials reaction, this ends with a description on how the materials could be used and developed in the future.

Förbehandling av lignocellulosa genom ångexplosion är en förbehandling av biomassa som förändrar strukturen i fibrernas cellväggar. Vid förbehandlingen värms biomassa med mättad ånga under tryck till minst 140 ˚C, detta leder till att flyktiga ämnen avgår från biomassan. När den uppvärmda biomassan är färdigbehandlad utsätts den för en kraftig trycksänkning vilket leder till att fukten i biomassan övergår till ånga och bidrar till ökad porositet, minskad materialstorlek och förändrad struktur i cellväggarna. Genom kartläggning av ett befintligt kokkärl på SCA R&D Centre och litteraturstudier inom området utforskas möjligheten att bygga om kokkärlet till ångexplosionsreaktor för laborativt bruk. Ett utformningsförslag togs fram varpå en termodynamisk modell över reaktionen skapades i Excel med hjälp av makrot Xsteam. Dimensionering av blåstank till förslaget gjordes baserat på ångexplosion av två kg tallflis med två fukthalter, 40 och 60%. Resultaten visar att en ombyggnation är möjlig, ångpannan begränsar dock ångtrycket till 10 bar. Vid behandling av två kg tallflis med en fukthalt om 40 respektive 60% dimensionerades anläggningens blåstank till 376 respektive 493 liter. Den nya reaktorn designades som skild från atmosfären. En sådan reaktor möjliggör framtida analys av bland annat flyktiga ämnen vilket kan bidra till effektivare tillvaratagande av restströmmar. / Pretreatment of lignocellulose by steam explosion is an energy efficient method that alters the structure of the fiber cell walls. Biomass is heated with pressurized saturated steam during the pretreatment to at least 140˚C, causing the release of volatile substances. Once the heated biomass is treated to desired severity, it undergoes a significant pressure reduction, causing the moisture in the biomass to turn into steam and contribute to increased porosity, reduced particle size and altered structure in the fiber cell walls. By examining an existing digester at the SCA R&D Centre and conducting literature studies in the field, the possibility of converting the digester into a steam explosion reactor for laboratory use is explored. A design proposal was developed, upon which a thermodynamic model of the reaction was created in Excel using the Xsteam macro. Dimensioning of the blow tank for the proposal was based on steam explosion of two kg pine chips with two moisture levels, 40% and 60%. The results indicate that such a conversion is possible, however, the steam pressure is limited to 10 bar overpressure due to the existing steam boiler. When treating two kg of pine chips with moisture content of 40% and 60% respectively, the sizing of the blow tank for the facility was determined to be 376 liters and 493 liters respectively. The new reactor was designed to be isolated from the atmosphere, enabling future analysis of volatile substances, which can contribute to a more efficient utilization of residual streams.

Lignocellulosic plants are the most abundant source of terrestrial biomass and are one of the potential sources of renewable energy that can replace the use of fossil fuels. For a country such as Sweden, where the forest industry accounts for 10% of the total export, there would be large economical benefits associated with increased biomass yield. The availability of research on wood development conducted in conifer tree species, which represent the majority of the forestry in Sweden, is limited and the majority of research has been conducted in model angiosperm species such as Arabidopsis thaliana. However, the large evolutionary distance between angiosperms and gymnosperms limits the possibility to identify orthologous genes and regulatory pathways by comparing sequence similarity alone. At such large evolutionary distances, the identification of gene similarity is, in most cases, not sufficient and additional information is required for functional annotation. In this thesis, two high-spatial resolution datasets profiling wood development were processed; one from the angiosperm tree Populus tremula and the other from the conifer species Picea abies. These datasets were each published together with a web resource including tools for the exploration of gene expression, co-expression and functional enrichment of gene sets. One developed resource allows interactive, comparative co-expression analysis between species to identify conserved and diverged co-expression modules. These tools make it possible to identifying conserved regulatory modules that can focus downstream research and provide biologists with a resource to identify regulatory genes for targeted trait improvement. / Lignocellulosa är den vanligast förekommande källan till markburen biomassa och är en av de förnybara energikällor som potentiellt kan ersätta användningen av fossila bränslen. För ett land som Sverige, där skogsindustrin som står för 10 \% av den totala exporten, skulle därför en ökad produktion av biomassa kunna ge stora ekonomiska fördelar. Forskningen på barrträd, som utgör majoriteten av svensk skog är begränsad och den huvudsakliga forskningen som har bedrivits på växter, har skett i modell organismer tillhörande gruppen gömfröiga växter som till exempel i Arabidopsis thaliana. Det evolutionära avståndet mellan gömfröiga (blommor och träd) och nakenfröiga (gran och tall) begränsar dock möjligheten att identifiera regulatoriska system mellan dessa grupper. Vid sådana stora evolutionära avstånd krävs det mer än att bara identifiera en gen i en modellorganism utan ytterligare information krävs som till exempel genuttrycksdata. I denna avhandling har två högupplösta experiment som profilerar vedens utveckling undersökts; ett från gömfröiga träd Populus tremula och det andra från nakenföriga träd (barrträd) Picea abies. Datat som behandlats har publicerats tillsammans med webbsidor med flera olika verktyg för att bland annat visa genuttryck, se korrelationer av genuttryck och test för anrikning av funktionella gener i en grupp. En resurs som utvecklats tillåter interaktiva jämförelser av korrelationer mellan arter för att kunna identifiera moduler (grupper av gener) som bevaras eller skilts åt mellan arter över tid. Identifieringen av sådana bevarade moduler kan hjälpa att fokusera framtida forskning samt ge biologer en möjlighet att identifiera regulatoriska gener för en riktad förbättring av egenskaper hos träd.