Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-05T17:08:43Z No. of bitstreams: 1 FLÁVIA CRISTINA DOS SANTOS LIMA - TESE (PPGEP) 2013.pdf: 7673702 bytes, checksum: df6fc75de6798e4e29b04c58f5bd63f6 (MD5) / Made available in DSpace on 2018-10-05T17:08:43Z (GMT). No. of bitstreams: 1 FLÁVIA CRISTINA DOS SANTOS LIMA - TESE (PPGEP) 2013.pdf: 7673702 bytes, checksum: df6fc75de6798e4e29b04c58f5bd63f6 (MD5) Previous issue date: 2013-06-14 / Com este trabalho objetivou-se estudar e definir as melhores condições para produção de xilitol utilizando o licor da pré-hidrólise ácida do bagaço do pedúnculo do caju. O bagaço do pedúnculo do caju obtido foi lavado, secado a 55 ºC, moído e peneirado (48 mesh); só então foi caracterizado e submetido a pré-hidrólise ácida utilizando-se H2SO4 a 3%, razão 1:6, por 1 hora. A caracterização da composição lignocelulósica revelou a presença de 18,31 ± 0,071% de celulose, hemicelulose 27,18 ± 0,01% e lignina 23,91 ± 0,02% e, após a pré-hidrólise ácida, 31,50 ± 0,02, 19,30 ± 0,09 e 32,21 ± 0,57% de celulose, hemicelulose e lignina, respectivamente. Após a realização da pré-hidrólise o licor foi submetido ao processo de remoção por lignina residual para eliminação dos compostos tóxicos ao metabolismo microbiano, de acordo com o planejamento experimental fatorial 23 com três repetições no ponto central; as melhores condições de remoção foram pH e tempo de contato em 4 e 20 min, respectivamente, e massa de lignina residual 0,65 g, obtendo-se uma remoção de 15% de xilose, 20% de glicose, 100% de hidroximetilfurfural e 100% de furfural. Um planejamento fatorial 24 com três repetições no ponto central foi utilizado para verificar a influência das concentrações de sulfato de amônio, cloreto de cálcio, farelo de arroz e do pH meio de fermentação sobre a concentração final de xilitol, produtividade volumétrica em xilitol, eficiência e o fator de conversão de xilose em xilitol. Os ensaios fermentativos foram realizados utilizando-se a levedura Candida guilliermondii CCT 3544, em frascos de erlenmeyer com 50 mL do meio, agitados a 200 rpm, 28 °C de 0 a 96 h. De acordo com os resultados a concentração de cloreto de cálcio e o pH influenciaram significativamente a bioconversão de xilose em xilitol. A análise geral dos resultados levou à conclusão de que 1 g/L de sulfato de amônio, 0,5 g/L de cloreto de cálcio, 5 g/L de farelo de arroz e o pH 4, representam a composição do meio mais adequada para a produção de xilitol no licor pré-hidrolisado do bagaço do pedúnculo de caju. Após a obtenção das melhores condições de cultivo e adsorção foi realizado um ensaio fermentativo em intervalos de tempo 0, 12, 24, 36 e 48 h em frascos de erlenmeyer com capacidade de 250 mL, ampliação de escala em 3 vezes, contendo 150 mL do meio in natura, concentrado e concentrado/tratado, com concentração inicial de células 107 células/mL. De acordo com os resultados, o licor tratado/concentrado representa o meio mais adequado para fermentação com maior concentração celular, 56,4 x 106 células/mL, em 36 h, e produção de xilitol de 3000,14 mg/L, resultando em uma produtividade de 0,063 g/L h com rendimento de bioconversão de 74,47% e eficiência de 81,21%, ao final de 48 h. / This work aimed to study and define the best conditions for xylitol production using liquor acid prehydrolysis of cashew bagasse. The cashew bagasse obtained was washed, dried at 55 ° C, milled and sieved (48 mesh); only then it was characterized and subjected to acid prehydrolysis using H2SO4 at 3%, 1:6 ratio, for 1 hour. The characterization of the lignocellulosic revealed the presence of 18.31 ± 0.071% of cellulose, hemicellulose 27.18 ± 0.01% and lignin 23.91 ± 0.02% and after acid prehydrolysis 31.50 ± 0.02, 19.30 ± 0.09 and 32.21 ± 0.57% cellulose, hemicellulose and lignin, respectively. Upon completion of the prehydrolysis, the liquor was subjected to the removal process by residual lignin for disposal of toxic compounds to microbial metabolism, according to the 23 experimental factorial planning with three replications at the central point, and the best conditions of removal, pH and contact time at 4 and 20 min, respectively and mass of 0.65 g residual lignin, obtaining a removal of 15% of xylose, 20% glucose, 100% hydroxymethylfurfural and 100% furfural. A 24 factorial planning with three replications at the central point was used to verify the influence of the concentrations of ammonium sulfate, calcium chloride, rice bran and pH the fermentation medium about the final concentration of xylitol, xylitol volumetric productivity, efficiency and the conversion factor of xylose to xylitol. The fermentation trials were carried out using the Candida guilliermondii CCT 3544 yeast in erlenmeyer flasks with 50mL of the medium, agitated at 200 rpm, 28 °C from 0 to 96 h. According to the results the concentration of calcium chloride and pH has significantly influenced the bioconversion of xylose to xylitol. The general analysis of the results led to the conclusion that 1 g/L of ammonium sulfate, 0.5 g L calcium chloride, 5 g/L of rice bran and pH 4 represent the most suitable composition of the medium for xylitol production in prehydrolyzed liquor of the cashew apple bagasse. After obtaining the best conditions of cultivation and adsorption was carried out a trial fermentation in time intervals 0, 12, 24, 36 and 48 h in erlenmeyer flasks with a capacity of 250 mL, scale application - 3 times, containing 150 mL of the medium in natura, concentrated and concentrate/treated with initial cell concentration of 107 cells/mL. According to the results the treated/concentrated liquor represents the most suitable way for fermentation, with a higher cell concentration, 56.4 x 106 cells/ mL in 36 h and xylitol production of 3000.14 mg/L, resulting in a productivity of 0.063 g/L h with a bioconversion yield of 74.47% and 81.21% efficiency at the end of 48 hours.

Submitted by Clebson Anjos (clebson.leandro54@gmail.com) on 2016-03-04T21:55:14Z No. of bitstreams: 1 arquivototal.pdf: 1992438 bytes, checksum: 7619ce6c21cea2362c1d633c136de464 (MD5) / Made available in DSpace on 2016-03-04T21:55:14Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1992438 bytes, checksum: 7619ce6c21cea2362c1d633c136de464 (MD5) Previous issue date: 2015-03-23 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Due to the amount of waste generated by industries and commitments to the environment, there has been a growing interest in the use of alternative energy sources for the generation of bio-products with added value, such as ethanol and xylitol. In this context, cashew peduncle has been considered a promising alternative to meet this demand in a more sustainable manner. Thus, the aim of this study was to assess the expansion of the experimental scale of biotechnological xylitol production using liquor from the acid treatment of cashew peduncle bagasse as substrate and Candida guilliermondii CCT 3544 yeast as fermentation agent. Cashew peduncle bagasse was washed, dried at 55°C, ground, sieved (48 mesh), characterized and submitted to acid hydrolysis. Then, a 23 + 3 factorial experimental design with central points was performed in order to verify the effect of variables temperature, bagasse / dilute acid ratio and acid concentration on the release of pentose and hexose from hydrolyzed liquors. After hydrolysis, the liquor was submitted to concentration process and the fermentation medium was prepared in 400 ml Erlenmeyer flasks in Bioreactor (1600 ml), stirred at 200 rpm, 28°C from 0 to 120 h using C. guilliermondii CCT 3544 yeast. The characterization of the lignocellulosic composition revealed the presence of 21.45 ± 0.31% cellulose, 10.96 ± 0.31% hemicellulose and 35.39 ± 0.97% lignin, respectively. It was found that the liquor from the acid treatment should operate under temperature conditions at level 1 (160 ° C) and acid concentration, bagasse / dilute acid ratio at level -1 (1%, 1: 6). The overall analysis of results led to the conclusion that C. guilliermondii CCT-3544 was able to grow in medium with hydrolyzate, and its maximum concentration of cell growth was 3.5 g L-1 in both cases. However, the fermented concentrate obtained maximum production at 48 h of fermentation, but the fermented hydrolyzate in bioreactor produced ethanol and xylitol, with maximum xylitol production at 6 h and maximum ethanol production at 48 h of fermentation. / Em virtude da quantidade de resíduos gerados pelas indústrias e dos compromissos assumidos com o meio ambiente, tem-se verificado um crescente interesse pela utilização de fontes alternativas de energia para geração de bioprodutos com valor agregado, como o etanol e xilitol. Neste contexto, o pedúnculo do caju tem sido considerado uma alternativa promissora para atender à demanda de forma mais sustentável. Em vista disso, o objetivo desta pesquisa foi estudar a ampliação de escala experimental da produção biotecnológica de xilitol utilizando o licor do tratamento ácido do bagaço do pedúnculo do caju como substrato e como agente de fermentação a levedura Candida guilliermondii CCT 3544. O bagaço do pedúnculo do caju obtido foi lavado, seco a 55 ºC, moído, peneirado (48 mesh), caracterizado e submetido à hidrólise ácida. Em seguida, realizou-se um planejamento experimental fatorial 23 + 3 pontos centrais com o intuito de verificar as influências das variáveis: temperatura, proporção bagaço/ácido diluído e concentração do ácido na liberação de pentoses e hexose dos licores hidrolisados. Após hidrólise o licor foi submetido ao processo de concentração e o meio de fermentação preparado em frascos de Erlenmeyer com 400 mL do meio com licor concentrado e em Biorreator (1600 mL), agitados a 200 rpm, 28 °C de 0 a 120 h, utilizando-se a levedura C. guilliermondii CCT 3544. A caracterização da composição lignocelulósica revelou a presença de 21,45 ± 0,31% de celulose, hemicelulose 10,96 ± 0,31% e lignina 35,39 ± 0,97%, respectivamente. Verificou-se que o licor do tratamento ácido deve operar sob condições de temperatura ao nível 1 (160 °C), concentração de ácido, proporção bagaço/ácido diluído ao nível -1 (1% e 1:6). O fermentado do hidrolisado concentrado obteve produção máxima com 48 h de fermentação, já o hidrolisado fermentado em biorreator produziu etanol e xilitol simultaneamente com máxima produção de xilitol com 6 h e etanol com 48 h de fermentação.

<p>Municipal wastewater treatment plants treat wastewater such as domestic and industrial sewage and recirculates the clean water back into nature’s waterways. However, the wastewater treatment process is costly and complex. The cost of running a municipal wastewater treatment plant is funded via ratepayer fee dollars from customers and therefore receives a fixed budget for which to run the plant according to environmental standards. A local initiative was established to upgrade a Midwestern municipal wastewater facility to utilize biomass renewable energy to a greater extent than what is used by the wastewater facility. The first phase of the initiative tested the suitability of utilizing organic substrates from local industrial plants with the potential to produce larger amounts of biogas via anaerobic digestion. The analysis evaluated the technical and financial viability of utilizing biomass technologies to help power the facility efficiently and economically. The financial and technical analysis will include a cost-benefit analysis by comparing current and forecasted natural gas demand and costs for running heating the WWTP to biogas produced by the anerobic digesters. The results of the research study found that the industrial waste substrates are suitable for anaerobic digestion and yield a higher biogas potential than what is currently used for anaerobic digestion by the WWTP. The initial financial analysis found it is feasible and economical, for at least certain months of the year, for the WWTP to refrain from purchasing natural gas and instead utilize the produced biogas.</p>

This dissertation is focused on analysing the potencial in production and distribution of chosen biocommodity in the less favoured areas of South Bohemian region. As the alternate aim was determined ecological rural tourism and its perspective as one of the possible ways of developing less favoured areas. The work highlights the distinctions of organic agriculture and its principles, shows organic activities as a way of possible developmnet of montane and submontane areas and detects potencial of growth of this branch for the future.

No description available.

<p><a href="" target="_blank">Synthetic microbial communities (SynComs) are an important focus in modern microbiology. SynComs are used for studying the dynamics of naturally occurring microbial communities ranging from soil to the human gut. Synthetic refers to the assemblage of some or all the members of these communities in a laboratory setting. SynComs allow for communities difficult to study <i>in situ</i> to be studied in a controlled environment, or they may be used to create beneficial products like biofertilizers. When SynComs are used as products, the focus shifts to optimizing a desired outcome of a culture. For biofertilizers, a high diversity is key to producing a functionally redundant product for stimulating plant growth. Media manipulation is a common approach for inducing community changes in a SynCom. Amino acids (AA) are a media supplement that soil microbes (often the components of biofertilizers) are particularly fond of to support their metabolic activities. This study took a scale-up approach to assess the changes in growth dynamics of a SynCom (Environoc© 401) when supplemented with different concentrations of commercially available AA products from plant and animal sources. Expanding from microplates, to shake flasks, then into a 4L bioreactor, Environoc© 401 cultures were compared for their maximum growth rate, time in lag phase, and final growth (optical density or viable cell density) when supplemented with these AA products at various concentrations. Furthermore, Illumina sequencing of the 16S rRNA gene was used to evaluate community-level changes from these treatments based on taxonomic, alpha (Chao 1 and Shannon indices), and beta diversity (Generalized UniFrac) of shake flask and bioreactor samples. Quantitative PCR was also used to assess the relative change of three select species of the SynCom in each AA treatment. Shake flask data revealed significant changes in the growth dynamics of the SynComs within AA treatment groups. Whether the AA was animal or plant derived, generally as the concentration of AA increased, the maximum growth rate decreased, lag time increased, and final growth readings increased. The best AA supplement and rate according to the growth metrics and <i>Curveball </i>analysis was Stimtide at a 33% supplementation rate. This was compared with the control at the bioreactor scale where it showed higher overall final growth and a higher taxonomic and alpha diversity. The scale-up approach to this study was successful at selecting the best amino acid supplement type and rate despite having less sophisticated control and monitoring compared to larger scales (i.e. the bioreactor). Use of the <i>Curveball</i> modeling program was useful for treatment group selection but did not always predict the outcomes seen in the live cultures. The use of AA as a media supplement can increase growth and diversity of a SynCom, though not all AA supplements or rates affect growth and community dynamics in the same way</a>.</p>

<p dir="ltr">This thesis investigated the international trade dynamics of wood pellets within the context of renewable energy transitions amid climate change concerns. In the first chapter, by employing gravity models with different estimators and specifications, we analyzed the determinants of trade flows of wood pellets. Additionally, we forecasted the future trade values of wood pellets under five shared socioeconomic pathways (SSP) scenarios. Our results showed the effects of some factors such as GDP of exporters, contiguity, and the distance between the two trading countries, were consistent with the economic theory. On the other hand, some other factors exhibited unexpected effects or conflicting results across the models. Regarding projections under five SSP scenarios, our results indicated substantial growth in trade flows, although potential overestimations are acknowledged due to the imposed assumptions. SSP3, which reflects a nationalistic scenario, is projected to have the smallest trade flows, while SSP5 anticipates the highest trade flows due to diminishing inequality and high GDP growth. Also, regional shifts in trade patterns were forecasted, with East Asia and Southeast Asia gaining prominence in imports and exports, respectively. Conversely, Europe’s imports and exports as well as North America’s exports are expected to decrease their shares in the global trade. Overall, our findings emphasize the complexity of trade determinants and underscore the need for nuanced forecasting methodologies to anticipate future trade dynamics accurately amidst evolving global scenarios of wood pellet trade.</p><p dir="ltr">The second chapter evaluated the effects of the Paris Agreement on the international trade of wood pellets. The growing concern about climate change has encouraged the global communities to take actions toward climate-change mitigation. As a form of such efforts, the Paris Agreement was signed in 2015 by 196 parties around the world and went into force in 2016. As a means to mitigate climate change, wood pellets have been used as fuels alternative to fossil fuels. Traditionally, Europe was the primary importer of wood pellets, mostly sourced from the United States and Canada. In the last decade, there has also been a significant uptake in East Asia, indicating shifting trade patterns and market dynamics in the wood pellet industry. This study employed an event-study framework to analyze the impact of the Paris Agreement on the global trade of wood pellets from 2014 to 2019, using import and export data at the regional level. Our results revealed distinct patterns in responses to the Paris Agreement in terms of adjustment speed and magnitude. Europe exhibited a rapid increase in both imports and exports immediately after the Paris Agreement. East Asia demonstrated a delayed yet substantial rise in imports, particularly after 2018. North America also swiftly expanded exports, following the agreement, while Southeast Asia emerged as an important exporter, particularly in supporting the East Asian market from 2017 onwards. We also found an increase in exports of non-pellet wood fuels from Africa. This finding indicates that international climate agreements not only contribute to the overall expansion of the global market of wood pellets but also reshape the market by involving more countries in international efforts to mitigate climate change.</p>

<p>The potential use of enzymes in industrial synthesis of epoxidized soybean oil has been limited through the high cost of the enzyme catalyst, in this work we evaluate the effectiveness of chemo enzymatic epoxidation of high oleic soybean oil (HOSBO) using lipase B from <i>Candida antarctica </i>(CALB) on immobilization support Immobead 150 and H₂O₂in a solvent-free system. Additionally, we evaluated the production decay rates for hydrolytic activity and epoxide product formation over consecutive batches to determine half-life of the enzyme catalyst. </p> <p> Batch epoxidation of HOSBO using CALB on 4wt% loading shows yields higher than 90% after 12 hrs. of reaction, and with a correlation to the consumption of double bonds suggesting that the reaction is selective and limiting side product reactions. Non-selective hydrolysis of oil was not found beyond the initial hydrolysis degree of raw HOSBO. Evaluations of decay given by epoxide product formation and released free fatty acids shows a half-life of the enzyme catalyst on these activities is of 22 ad 25 hrs. respectively. Finally, we evaluated the physical parameters influencing this decay, and found that H₂O₂ presence is the most important parameter of enzyme inactivation with no significant effect from its slowed addition. We propose a new reactor configuration for the analysis of the specific steps on epoxide formation through peracid intermediates. </p>