A exploração indiscriminada dos combustíveis fósseis vem alertando para o colapso próximo do suprimento de energia. Fontes alternativas vêm sendo exploradas com o propósito de apresentarem-se como combustíveis com o mesmo potencial, além de estarem inseridas em um contexto de desenvolvimento sustentável. O Brasil, por consolidar sua posição com forte mercado agroindustrial e dispor de uma grande variedade de unidades agrícolas possui como subprodutos uma alta quantidade de resíduos, como o sabugo de milho. Assim, buscam-se viabilizar metodologias que tornem a exploração desta fonte economicamente vantajosa para a obtenção de etanol de segunda geração (2G). Novas metodologias vêm propondo o emprego de tensoativos como aditivos tanto no prétratamento quanto na hidrólise enzimática de materiais lignocelulósicos. Neste contexto, o presente trabalho objetivou estudar a hidrólise enzimática do sabugo de milho pré-tratado por ácido diluído na presença de diferentes concentrações do tensoativo Tween 80 em associação com a dosagem do complexo enzimático Cellic CTec2 para a obtenção de um hidrolisado rico em glicose para obtenção de etanol pela levedura Scheffersomyces stipitis CBS 6054 através do processo SHF (Separate Hydrolysis and Fermentation). Os ensaios foram conduzidos de acordo com planejamento experimental 23 com face centrada e 3 repetições no ponto central. As variáveis estudadas foram: concentração de surfactante no pré-tratamento e na hidrólise enzimática e dosagem do complexo enzimático. Os resultados mostraram que o uso do surfactante no pré-tratamento com ácido sulfúrico diluído surtiu maior efeito na remoção de lignina e hemicelulose quando empregado na concentração de 10% (m/m). Nesta condição foi possível observar um aumento (21,1%) na perda de celulose em relação ao pré-tratamento sem a presença de surfactante. A maior diminuição na cristalinidade (81,23%) foi com o uso de 10% do tensoativo. A análise da superfície de resposta permitiu determinar as condições ótimas do processo SHF para obtenção de máximo rendimento em glicose (entre 80 e 90 %) que foi quando a concentração de surfactante no pré-tratamento aumentou de 0 a 10 % (m/m) mantendo-se constante em seu nível superior a concentração de surfactante na hidrolise enzimática (10 % m/m) com redução na dosagem de enzima (25,50 FPU/gmaterial lignocelulósico seco). Nestas condições experimentais obteve-se favorecimento no rendimento em glicose (80,54%) e concentração em glicose (61,98 g/L) no meio reacional concomitantemente com o favorecimento no rendimento em xilose (70,66%). Esta levedura fermentou concomitantemente os açúcares (glicose, xilose e celobiose) a etanol com elevados fator de conversão (0,37 g/g) e produtividade volumétrica (1,02 getanol/L.h). A velocidade especifica máxima de consumo destes açúcares foi favorecida na seguinte ordem: glicose, celobiose e xilose. Após esta fermentação foi obtido um material com uma superfície mais porosa e fragmentada. Este fato evidenciou que o complexo enzimático agiu eficientemente quebrando a celulose cristalina obtendo um material amorfo. Espera-se que este trabalho tenha contribuído para o desenvolvimento de uma tecnologia alternativa para a produção de etanol por via biotecnológica a partir da fração lignocelulósica do sabugo de milho, a fim de mitigar os impactos ambientais intrínsecos ao processo. / The indiscriminate exploitation of fossil fuels has been warning of the near collapse of the energy supply. Alternative sources have been explored with the purpose of presenting themselves as fuels with the same potential, besides being inserted in a context of sustainable development. Brazil, by consolidating its position with a strong agroindustrial market and having a wide variety of agricultural units, has as a by-product a high amount of waste, such as corn cob. Thus, we seek to make feasible methodologies that make the exploitation of this source economically advantageous to obtain second generation etanol (2G). New methodologies have proposed the use of surfactants as additives in both pretreatment and enzymatic hydrolysis of lignocellulosic materials. In this context, the present work aimed to study the enzymatic hydrolysis of diluted-acid pretreated corn cob in the presence of different concentrations of the Tween 80 surfactant in combination with the dosage of the Cellic CTec2 enzymatic complex to obtain a glucose rich hydrolysate to produce ethanol by the yeast Scheffersomyces stipitis CBS 6054 in SHF (Separate Hydrolysis and Fermentation) process. The experiments were conducted according to experimental design 23 with centered face and 3 repetitions at the central point. The variables studied were: concentration of surfactant in the pretreatment and in the enzymatic hydrolysis and dosage of the enzymatic complex. The results showed that the use of surfactant in the pretreatment with diluted sulfuric acid had a greater effect on the removal of lignin and hemicellulose when used at the concentration of 10% (w/w). In this condition, the cellulose content was decreased by 21.1% as compared with the amount presents in the diluted-acid corn cob pretreatment without surfactant. The greatest decrease in crystallinity (81.23%) was with the use of 10% of the surfactant. The response surface analysis allowed to determine the optimum conditions of the SHF process to obtain maximum glucose yield (between 80 and 90%), when the pre-treatment surfactante concentration increased from 0 to 10% (w/w) with a reduction in the enzyme dosage (25,50 FPU/g dry lignocellulosic material) at a higher level than the surfactant concentration in the enzymatic hydrolysis. In these experimental conditions, glucose yield (80.54%) and glucose concentration (61.98 g/L) in the reaction medium were favored concomitantly with xylose yield (70.66%). This yeast concomitantly fermented the sugars (glucose, xylose and cellobiose) to ethanol with high conversion factor (0.37 g/g) and volumetric productivity (1.02 getanol/L.h). The maximum specific velocity of consumption of these sugars was favored in the following order: glucose, cellobiose and xylose. After this fermentation was obtained a material with a more porous and fragmented surface. This fact evidenced that the enzymatic complex acted efficiently breaking down the crystalline cellulose obtaining an amorphous material. It is hoped that this work had contributed to the development of an alternative technology to produce ethanol by Biotechnological route from the corn cob lignocellulosic fraction in order to mitigate the environmental impacts intrinsic to the process.

Cob, as an arts-based research process, creates movements and moments of survival. Survival is an ideological construction and an actual, local practice. Survival is also about desiring and fulfilling arts-based desires to work with the land through academic and material scavenging. Cob creates strategies for surviving, for working with our respective environments wisely. Cob building teaches people how to negotiate the natural economy and their relationships to labor and each other through an artistic and intimate practice. From a feminist poststructural lens, survival happens on the local level, between and with people. Cob building creates knowledge through creative, kinesthetic, and collaborative engagement. As a feminist poststructuralist, arts-based research allows me to examine local action and interaction among people, positionalities, and competing differences. Rather than appeasing the modern impulse to objectify and rationalize an end-point or an object- oriented view of the production of art, feminist poststructural theory works to problematize the end-point. Through cob building, a rich, arts-based process, I call into question the modern impulse to find Truth and ask that we be aware of developing new oppressions when working toward equity and justice. Cob building teaches people how to engage together within the form of artistic creation. Cob is an arts-based research process that includes the land as an integral part of its canvas. In order to articulate, uncover, and engage the claim that, as an arts-based process, cob creates movements and moments of survival, I use the arts-based process, a/r/tography. This a/r/tographical text does not offer an end point but works to recreate moments and movements of cob building as an arts-based research project. A/r/tography helps to layer the movements of arts-based survival within cob building and this text. Throughout this work, the arts-based process of cob building is the overlying metaphor for the construction of the structure of this text. As the chapters move forward, the structure builds up.

Production of xylanase and itaconic acid (IA) from Aspergillus terreus NRRL 1960 from agricultural residues was investigated in this study. Two different media were tested and the medium having itaconic acid inducing capacity was chosen for further studies due to its high xylanase and IA production capacity. The best xylan concentration was found as 2% (w/v). Addition of commercial xylanase to production culture resulted in higher initial simple sugar concentration which increased IA production slightly but decreased xylanase production. Among tested agricultural residues / corn cob, cotton stalk and sunflower stalk, the highest xylanase production was obtained on corn cob. Increasing the corn cob concentration and applying wet heat pretreatment increased the xylanase production level. In a two-step fermentation process, 70000 IU/L xylanase production was achieved in a medium containing 7% wet heat treated corn cob followed by 17 g/L IA production in a medium containing 10% glucose. Molecular weight and isoelectric point of xylanase were found as 19 kDa and pH 9.0, respectively. The enzyme was optimally active at 50&deg / C and pH 6.5-7.0. Kinetic experiments at 50&deg / C and pH 7.0 resulted in apparent Km and Vmax values of 2.5&plusmn / 0.05 mg xylan/mL and 50.2&plusmn / 0.4 IU/&micro / g protein, respectively. The major products of birchwood xylan hydrolysis were determined by thin layer chromatography as xylobiose and xylotriose. These findings indicate that the enzyme could be advantageous for use in different industrial applications due to its low molecular weight and its potential use for xylooligosaccharide production.

Šiame darbe yra nagrinėjamos kukurūzų grūdų ir burbuolių fizikinės-mechaninės savybės, jų brendimo laikotarpyje, veikiant pusiau statine apkrova. Literatūros apžvalgoje atlikta kukurūzų burbuolių ir grūdų fizikinių-mechaninių savybių bei grūdų tamprumo modulio mokslinių tyrimų analizė. Moksliniai eksperimentiniai tyrimai buvo atlikti 2012 metų rugsėjo-spalio mėnesiais, dukart savaitėje, Žemės ūkio mašinų tyrimų laboratorijoje fizikinių-mechaninių savybių tyrimo mašina „Instron 5960“. Eksperimentiniais tyrimais nustatyti kukurūzų grūdų ir burbuolių biometriniai rodikliai. Tirtas kukurūzų burbuolių atsparumas lenkimui ir gniuždymui. Atlikti grūdo atskyrimo jėgos nustatymo spaudžiant juos eilutėje specialiu antgaliu tyrimai. Atliktas grūdų gniuždymo bandymas, spaudžiant grūdą iki visiško suirimo. Tyrimų duomenys apdoroti statistiškai. Tyrimais nustatyta, kad grūdams bręstant, rugsėjo-spalio mėnesiais, kukurūzų grūdų drėgnis sumažėja nuo 50,94±1,64% iki 36,21±0,52%, o maksimali jėga, reikalinga suardyti grūdą, padidėja nuo 91,54±16,75 N iki 200,67±18,43 N. / This study was carried out to determine the physical and mechanical properties in different physiological maturity stage of corn grains and corn ears. The study of the mechanical properties of corn grains and ears were performed under quasi-static conditions with the unit “Instron-5960”. Corn ears bending were determined, when the gap between the support beams was 60 mm and 120 mm. The rupture force of ear breaking decreases with an increasing of distance between the supports. The grain was loaded at three different orientations: over the length, over the width and over the thickness. Single grain was placed between two parallel plates and gradually compressed, while simultaneously recording the force and the corresponding deformation that occurred until the grain ruptured. At this point the force suddenly decreased, while the deformation continued. In most cases the initial portion of the load-deformation curve of the grain is approximately linear up to certain levels of deformation beyond which it became non-linear. The observed bioyield point represents the yield point in the biological materials. This is an indication of initial cell rupture in the cellular structure of the material. Research data were processed statistically. The results showed that the max rupture force of corn grain increased from 91.54±16.75 N to 200.67±18.43 N by decreasing the moisture content from 50.94±1.64% to 36.21±0.52%, respectively. 5 conclusions summarize this work and, finally, the list of... [to full text]

Darbe pateikti kombainų su tangentiniu kūlimo aparatu ir dviem ašiniais – rotoriniais šiaudų separatoriais kukurūzų burbuolių nuėmimo grūdų nuostolių ir sužalojimo tyrimų rezultatai. Gamybinėmis sąlygomis, nuimant kukurūzų burbuoles, įvertintas kombaino su tangentiniu kūlimo aparatu ir dviem ašiniais rotoriniais separatoriais darbas ir pagrįsti kūlimo aparato racionalūs technologiniais parametrais. Literatūros apžvalgoje įvertinta kukurūzų burbuolių nuėmimo technologijos, kitų tyrėjų nustatyti burbuolių kūlimo technologiniai parametrai. Lietuvoje gamybinėmis sąlygomis nėra tirtas kukurūzų burbuolių nuėmimas, nenustatyta kūlimo aparato racionalūs technologiniai parametrai ir jų įtaka grūdų sužalojimui. Nustatyta, kad kuliant vidutinio drėgnumo kukurūzų burbuoles, leistinoji grūdų sužalojimo riba 3% nebuvo viršyta, kai kūlimo būgno spragilai judėjo 11,3 m s-1. Kombaine su dviem ašiniais rotoriniais separatoriais galima sumažinti kūlimo būgno spragilų judėjimo greitį, nes nevisiškai iškultas burbuoles iškulia ašinių rotorinių separatorių dantys. Grūdų sužalojimui sumažinti reikia suderinti kūlimo būgno spragilų judėjimo greitį ir tarpą tarp būgno spragilų ir pobūgnio skersinių juostų. Kombainuose Claas Lexion racionalus tarpas tarp kūlimo būgno spragilų ir pagrindinio pobūgnio trečiosios skersinės juostos priklauso nuo kuliamų burbuolių vidutinio skersmens ir gali būti keičiamas nuo 27 iki 34 mm. Kombainas Claas Lexion 600 per technologinę valandą prikūlė 52,33±4,56 t grūdų... [toliau žr. visą tekstą] / This work presents the results of maize harvesting, using combine harvester with two axial rotary separators, research for 2011-2012. Literature study has shown that there are not many researches made on maize harvesting in Lithuania. Studies have found that the average moisture content of threshing corn cobs, grain permissible limit of 3% of the damage has not been exceeded, the threshing cylinder peripheral speed 11.3 m s -1. It was found that minimum grain scattered on soil and grains damaged were when feed rate were 19.9 kg s-1. Average grain losses were > 300 kg ha-1. The upper scaled sieve of combine harvester should be replaced with long scaled sieve. Rational speed of tangential threshing apparatus rasp bars is 12 m s-1, and the gap between threshing cylinder and concave can be adjusted 30 to 36 mm. The gap between the threshing drum rasp bars and concave crossbars has an impact on grain damage.

Die chronisch obstruktive Bronchitis des Pferdes ist charakterisiert durch Bronchospasmus, Entzündung und Dyskrinie. Der Bronchospasmus wird als Ergebnis der direkten Wirkung von Entzündungsmediatoren und der indirekten Wirkung des autonomen Nervensystems angesehen. Vorkommen und Eigenschaften β-adrenerger und muskarin-cholinerger Rezeptoren im equinen Respirationstrakt wurden bislang nicht umfassend untersucht. Aus diesem Grund wurden in der vorliegenden Arbeit beide Rezeptorsysteme in drei Segmenten des Respirationstraktes (Lungenparenchym, Bronchial- und Trachealepithel mit der darunter liegenden glatten Muskulatur) von gesunden und an COB erkrankten Pferden mit Hilfe von Radioligandbindungsstudien und Adenylatzyklase- bzw. Phospholipase C-Assay untersucht. Bei gesunden Pferden konnte eine Zunahme der Anzahl β-adrenerger Rezeptoren von den großen Atemwegen bis zum Lungenparenchym festgestellt werden. β-adrenerge Rezeptoren zeigten in Verdrängungsexperimenten mit Agonisten in allen drei Abschnitten einen Anteil hochaffine, an G-Protein-gekoppelte Rezeptoren von ca. 35 %. In allen drei Segmenten konnten die Subtypen β1 und β2 im Verhältnis von 20:80 % nachgewiesen werden. Die Dominanz des β2-Subtypes konnte außerdem durch die für den β2-Subtyp charakteristische Reihenfolge der pharmakologischen Wirkungsstärke von Agonisten ((-)-Isoprenalin > (-)- 102 Zusammenfassung Adrenalin > (-)-Noradrenalin) bestätigt werden. Darüber hinaus konnte gezeigt werden, dass β-adrenerge Rezeptoren in Membranpräparationen der drei Segmente in der Lage waren das Adenylatzyklase-System zu aktivieren. Muskarin-cholinerge Rezeptoren zeigten im Gegensatz zu den β-adrenergen Rezeptoren eine Abnahme der Rezeptorzahl von den großen Atemwegen bis zum Lungenparenchym. Der Anteil hochaffiner, an G-Protein gekoppelter muskarin-cholinerger Rezeptoren betrug in allen drei Segmenten ca. 35 %. Im Lungenparenchym wurden sowohl M1- (24-28 %), als auch M2- (. 50 %) und M3-Rezeptoren (. 40 %) nachgewiesen, während in den Atemwegen nur M2- und M3-Rezeptoren im Verhältnis von ungefähr 80:20 % identifiziert wurden. Während M2- Rezeptoren das Adenylatzyklase-System hemmten, aktivierten M1- bzw. M3-Rezeptoren das Enzym Phospholipase C. Bei der COB wurden keine wesentlichen Unterschiede im muskarin-cholinergen System zwischen gesunden und an COB-erkrankten Pferden festgestellt. Es konnte lediglich eine tendenzielle Abnahme der Rezeptordichte im Lungenparenchym festgestellt werden. Im Gegensatz dazu wurde bei COB-Pferden eine signifikante Abnahme der Anzahl β-adrenerger Rezeptoren im Lungenparenchym (333,4 ± 27,1 vs. 496,1 ± 23,4 fmol/mg Protein) und in den Bronchien (90,4 ± 19,0 vs. 155,1 ± 19,6 fmol/mg Protein) beobachtet, wobei beide Subtypen betroffen zu sein scheinen. Die Affinität für ICYP war dabei unverändert. Außerdem war das Vermögen der β-adrenergen Rezeptoren an die α-Untereinheit von G-Proteinen zu koppeln in beiden Segmenten vermindert (Lungenparenchym 24 % vs. 34 %, Bronchien 25 % vs. 34 %). Die Abnahme der Anzahl β-adrenerger Rezeptoren und der reduzierte Anteil hochaffiner Bindungsstellen für Isoprenalin widerspiegelten sich in der verminderten Wirkung von Isoprenalin die Adenylatzyklase zu stimulieren (Lungenparenchym 74,9 vs. 133,7 pmol/mg Protein/min, Bronchien 101,4 vs. 142,0 pmol/mg Protein/min). Das Kopplungsvermögen von Gs-Protein an die Adenylatzyklase bzw. die Aktivität der Adenylatzyklase selbst waren unverändert. An Membranen der Trachea von COB-Pferden konnten weder in der Anzahl, noch im Verhältnis der Subtypen, dem Kopplungsvermögen an Gs-Protein oder der Aktivität der Adenylatzyklase Veränderungen beobachtet werden. Die Ergebnisse zeigen, dass während einer COB die inhibitorische Funktion des β-adrenergen Rezeptor-G-Protein-Adenylatzyklase-Systems vermindert ist, während das exzitatorische muskarin-cholinerge System unverändert bleibt. β-adrenerge Rezeptoren scheinen somit für die Pathophysiologie der COB von Bedeutung sein. Die Abnahme der Rezeptoren könnte auch die z. T. unzureichende Wirkung der Therapie mit β2-Sympathomimetika erklären.

A exploração indiscriminada dos combustíveis fósseis vem alertando para o colapso próximo do suprimento de energia. Fontes alternativas vêm sendo exploradas com o propósito de apresentarem-se como combustíveis com o mesmo potencial, além de estarem inseridas em um contexto de desenvolvimento sustentável. O Brasil, por consolidar sua posição com forte mercado agroindustrial e dispor de uma grande variedade de unidades agrícolas possui como subprodutos uma alta quantidade de resíduos, como o sabugo de milho. Assim, buscam-se viabilizar metodologias que tornem a exploração desta fonte economicamente vantajosa para a obtenção de etanol de segunda geração (2G). Novas metodologias vêm propondo o emprego de tensoativos como aditivos tanto no prétratamento quanto na hidrólise enzimática de materiais lignocelulósicos. Neste contexto, o presente trabalho objetivou estudar a hidrólise enzimática do sabugo de milho pré-tratado por ácido diluído na presença de diferentes concentrações do tensoativo Tween 80 em associação com a dosagem do complexo enzimático Cellic CTec2 para a obtenção de um hidrolisado rico em glicose para obtenção de etanol pela levedura Scheffersomyces stipitis CBS 6054 através do processo SHF (Separate Hydrolysis and Fermentation). Os ensaios foram conduzidos de acordo com planejamento experimental 23 com face centrada e 3 repetições no ponto central. As variáveis estudadas foram: concentração de surfactante no pré-tratamento e na hidrólise enzimática e dosagem do complexo enzimático. Os resultados mostraram que o uso do surfactante no pré-tratamento com ácido sulfúrico diluído surtiu maior efeito na remoção de lignina e hemicelulose quando empregado na concentração de 10% (m/m). Nesta condição foi possível observar um aumento (21,1%) na perda de celulose em relação ao pré-tratamento sem a presença de surfactante. A maior diminuição na cristalinidade (81,23%) foi com o uso de 10% do tensoativo. A análise da superfície de resposta permitiu determinar as condições ótimas do processo SHF para obtenção de máximo rendimento em glicose (entre 80 e 90 %) que foi quando a concentração de surfactante no pré-tratamento aumentou de 0 a 10 % (m/m) mantendo-se constante em seu nível superior a concentração de surfactante na hidrolise enzimática (10 % m/m) com redução na dosagem de enzima (25,50 FPU/gmaterial lignocelulósico seco). Nestas condições experimentais obteve-se favorecimento no rendimento em glicose (80,54%) e concentração em glicose (61,98 g/L) no meio reacional concomitantemente com o favorecimento no rendimento em xilose (70,66%). Esta levedura fermentou concomitantemente os açúcares (glicose, xilose e celobiose) a etanol com elevados fator de conversão (0,37 g/g) e produtividade volumétrica (1,02 getanol/L.h). A velocidade especifica máxima de consumo destes açúcares foi favorecida na seguinte ordem: glicose, celobiose e xilose. Após esta fermentação foi obtido um material com uma superfície mais porosa e fragmentada. Este fato evidenciou que o complexo enzimático agiu eficientemente quebrando a celulose cristalina obtendo um material amorfo. Espera-se que este trabalho tenha contribuído para o desenvolvimento de uma tecnologia alternativa para a produção de etanol por via biotecnológica a partir da fração lignocelulósica do sabugo de milho, a fim de mitigar os impactos ambientais intrínsecos ao processo. / The indiscriminate exploitation of fossil fuels has been warning of the near collapse of the energy supply. Alternative sources have been explored with the purpose of presenting themselves as fuels with the same potential, besides being inserted in a context of sustainable development. Brazil, by consolidating its position with a strong agroindustrial market and having a wide variety of agricultural units, has as a by-product a high amount of waste, such as corn cob. Thus, we seek to make feasible methodologies that make the exploitation of this source economically advantageous to obtain second generation etanol (2G). New methodologies have proposed the use of surfactants as additives in both pretreatment and enzymatic hydrolysis of lignocellulosic materials. In this context, the present work aimed to study the enzymatic hydrolysis of diluted-acid pretreated corn cob in the presence of different concentrations of the Tween 80 surfactant in combination with the dosage of the Cellic CTec2 enzymatic complex to obtain a glucose rich hydrolysate to produce ethanol by the yeast Scheffersomyces stipitis CBS 6054 in SHF (Separate Hydrolysis and Fermentation) process. The experiments were conducted according to experimental design 23 with centered face and 3 repetitions at the central point. The variables studied were: concentration of surfactant in the pretreatment and in the enzymatic hydrolysis and dosage of the enzymatic complex. The results showed that the use of surfactant in the pretreatment with diluted sulfuric acid had a greater effect on the removal of lignin and hemicellulose when used at the concentration of 10% (w/w). In this condition, the cellulose content was decreased by 21.1% as compared with the amount presents in the diluted-acid corn cob pretreatment without surfactant. The greatest decrease in crystallinity (81.23%) was with the use of 10% of the surfactant. The response surface analysis allowed to determine the optimum conditions of the SHF process to obtain maximum glucose yield (between 80 and 90%), when the pre-treatment surfactante concentration increased from 0 to 10% (w/w) with a reduction in the enzyme dosage (25,50 FPU/g dry lignocellulosic material) at a higher level than the surfactant concentration in the enzymatic hydrolysis. In these experimental conditions, glucose yield (80.54%) and glucose concentration (61.98 g/L) in the reaction medium were favored concomitantly with xylose yield (70.66%). This yeast concomitantly fermented the sugars (glucose, xylose and cellobiose) to ethanol with high conversion factor (0.37 g/g) and volumetric productivity (1.02 getanol/L.h). The maximum specific velocity of consumption of these sugars was favored in the following order: glucose, cellobiose and xylose. After this fermentation was obtained a material with a more porous and fragmented surface. This fact evidenced that the enzymatic complex acted efficiently breaking down the crystalline cellulose obtaining an amorphous material. It is hoped that this work had contributed to the development of an alternative technology to produce ethanol by Biotechnological route from the corn cob lignocellulosic fraction in order to mitigate the environmental impacts intrinsic to the process.

Die chronisch obstruktive Bronchitis des Pferdes ist charakterisiert durch Bronchospasmus, Entzündung und Dyskrinie. Der Bronchospasmus wird als Ergebnis der direkten Wirkung von Entzündungsmediatoren und der indirekten Wirkung des autonomen Nervensystems angesehen. Vorkommen und Eigenschaften β-adrenerger und muskarin-cholinerger Rezeptoren im equinen Respirationstrakt wurden bislang nicht umfassend untersucht. Aus diesem Grund wurden in der vorliegenden Arbeit beide Rezeptorsysteme in drei Segmenten des Respirationstraktes (Lungenparenchym, Bronchial- und Trachealepithel mit der darunter liegenden glatten Muskulatur) von gesunden und an COB erkrankten Pferden mit Hilfe von Radioligandbindungsstudien und Adenylatzyklase- bzw. Phospholipase C-Assay untersucht. Bei gesunden Pferden konnte eine Zunahme der Anzahl β-adrenerger Rezeptoren von den großen Atemwegen bis zum Lungenparenchym festgestellt werden. β-adrenerge Rezeptoren zeigten in Verdrängungsexperimenten mit Agonisten in allen drei Abschnitten einen Anteil hochaffine, an G-Protein-gekoppelte Rezeptoren von ca. 35 %. In allen drei Segmenten konnten die Subtypen β1 und β2 im Verhältnis von 20:80 % nachgewiesen werden. Die Dominanz des β2-Subtypes konnte außerdem durch die für den β2-Subtyp charakteristische Reihenfolge der pharmakologischen Wirkungsstärke von Agonisten ((-)-Isoprenalin > (-)- 102 Zusammenfassung Adrenalin > (-)-Noradrenalin) bestätigt werden. Darüber hinaus konnte gezeigt werden, dass β-adrenerge Rezeptoren in Membranpräparationen der drei Segmente in der Lage waren das Adenylatzyklase-System zu aktivieren. Muskarin-cholinerge Rezeptoren zeigten im Gegensatz zu den β-adrenergen Rezeptoren eine Abnahme der Rezeptorzahl von den großen Atemwegen bis zum Lungenparenchym. Der Anteil hochaffiner, an G-Protein gekoppelter muskarin-cholinerger Rezeptoren betrug in allen drei Segmenten ca. 35 %. Im Lungenparenchym wurden sowohl M1- (24-28 %), als auch M2- (. 50 %) und M3-Rezeptoren (. 40 %) nachgewiesen, während in den Atemwegen nur M2- und M3-Rezeptoren im Verhältnis von ungefähr 80:20 % identifiziert wurden. Während M2- Rezeptoren das Adenylatzyklase-System hemmten, aktivierten M1- bzw. M3-Rezeptoren das Enzym Phospholipase C. Bei der COB wurden keine wesentlichen Unterschiede im muskarin-cholinergen System zwischen gesunden und an COB-erkrankten Pferden festgestellt. Es konnte lediglich eine tendenzielle Abnahme der Rezeptordichte im Lungenparenchym festgestellt werden. Im Gegensatz dazu wurde bei COB-Pferden eine signifikante Abnahme der Anzahl β-adrenerger Rezeptoren im Lungenparenchym (333,4 ± 27,1 vs. 496,1 ± 23,4 fmol/mg Protein) und in den Bronchien (90,4 ± 19,0 vs. 155,1 ± 19,6 fmol/mg Protein) beobachtet, wobei beide Subtypen betroffen zu sein scheinen. Die Affinität für ICYP war dabei unverändert. Außerdem war das Vermögen der β-adrenergen Rezeptoren an die α-Untereinheit von G-Proteinen zu koppeln in beiden Segmenten vermindert (Lungenparenchym 24 % vs. 34 %, Bronchien 25 % vs. 34 %). Die Abnahme der Anzahl β-adrenerger Rezeptoren und der reduzierte Anteil hochaffiner Bindungsstellen für Isoprenalin widerspiegelten sich in der verminderten Wirkung von Isoprenalin die Adenylatzyklase zu stimulieren (Lungenparenchym 74,9 vs. 133,7 pmol/mg Protein/min, Bronchien 101,4 vs. 142,0 pmol/mg Protein/min). Das Kopplungsvermögen von Gs-Protein an die Adenylatzyklase bzw. die Aktivität der Adenylatzyklase selbst waren unverändert. An Membranen der Trachea von COB-Pferden konnten weder in der Anzahl, noch im Verhältnis der Subtypen, dem Kopplungsvermögen an Gs-Protein oder der Aktivität der Adenylatzyklase Veränderungen beobachtet werden. Die Ergebnisse zeigen, dass während einer COB die inhibitorische Funktion des β-adrenergen Rezeptor-G-Protein-Adenylatzyklase-Systems vermindert ist, während das exzitatorische muskarin-cholinerge System unverändert bleibt. β-adrenerge Rezeptoren scheinen somit für die Pathophysiologie der COB von Bedeutung sein. Die Abnahme der Rezeptoren könnte auch die z. T. unzureichende Wirkung der Therapie mit β2-Sympathomimetika erklären.

This thesis investigates full-scale pipe stem reinforced cob walls under in-plane cyclic shear loads. Cob is the combination of clay subsoils, sand, straw and water that is built in lifts to produce monolithic walls. There is insufficient amount of information on cob as a building material in today’s age. The prior research that exists has examined varying straw content and type, water content, and mixture ratios to determine their effect on strength. There is currently one report that analyzes full-scale cob walls under in-plane loading. This thesis looks to iterate the full-scale tests and specifically studies the effect of reinforcement on cob walls. Concurrent to this research, another thesis was written that investigates a full-scale wire mesh reinforced cob wall under in-plane cyclic shear loads. From the data collected, a shear failure was suggested for the stem pipe wall. There appeared to be a large amount of ductility from the data and the cracks formed. Ductility, a seismic response modification factor (R-Factor) and stiffness were calculated using the yield point and ultimate loads.Iterations of this research and those performed in the past can be helpful in integrating cob in to the California Building Code.

O sabugo de milho, devido a sua estrutura lignocelulósica, pode servir como fonte de biomassa renovável na produção de açúcares solúveis que podem ser convertidos em produtos de elevados valores agregados, como etanol e outros. A hidrólise ácida é o método mais utilizado na obtenção de hidrolisado hemicelulósico de materiais lignocelulósicos ricos em açúcares fermentescíveis, sendo o açúcar xilose em maior concentração. A levedura fermentadora de xilose Scheffersomyces stipitis está entre os poucos organismos que utilizam a xilose e a glicose e exibem um sistema regulatório de transição entre o processo respiratório e o fermentativo. Este trabalho teve como objetivo contribuir para o desenvolvimento de uma tecnologia de obtenção de bioetanol por S. stipitis CBS 6054, a partir da fração hemicelulósica do sabugo de milho, avaliando a formulação nutricional do meio de fermentação. Como fonte de nitrogênio alternativa foi escolhida o farelo de soja. O hidrolisado hemicelulósico de sabugo de milho (HHSM), obtido por hidrólise ácida, foi concentrado a vácuo e tratado pela elevação e abaixamento de pH. O hidrolisado de farelo de soja foi obtido por hidrólise enzimática (Alcalase, 600C, 100 rpm, 3h). Para avaliar a solubilidade do hidrolisado de farelo de soja em HHSM (pH de 4,0 a 7,0) empregou-se planejamento fatorial 22 completo com análise de superfície de resposta (RSM). A suplementação do HHSM com a proteína de farelo de soja solubilizada em associação ou não com outros nutrientes (ureia e sulfato de amônio) na obtenção de bioetanol por S. stipitis foi avaliada por meio de um planejamento fatorial 23 completo com RSM. A fermentação foi realizada em frascos de Erlenmeyer (125 mL) contendo 50 mL de meio sob agitação de 150 rpm e 30 °C. A concentração de inoculo foi de 1,5 g/L de células. Os resultados mostraram que a hidrólise ácida favoreceu a remoção da fração hemicelulósica (88,05%) com pouca alteração na celulose (10,06%) e da lignina (27,07%) com relação ao material in natura, proporcionando um hidrolisado hemicelulósico rico em xilose (28,30 g/L) com baixas concentrações de compostos fenólicos e furanos. O tratamento do HHSM reduziu seu teor proteico em relação ao hidrolisado concentrado (74,76%) e hidrolisado original (28,53%). O farelo de soja foi de boa qualidade apresentando solubilidade da proteína em KOH igual a 82,99% e índice de urease igual a 0,00. A hidrólise enzimática de farelo de soja hidrolisou 50,45% mais proteína do que a extração aquosa de proteína de farelo de soja, obtendo-se 45 g/L de proteína solubilizada. Na quantificação de proteína pelo método de Lowry foi necessário levar em consideração a presença de espécies interferentes do HHSM. A máxima solubilização da proteína de soja (9,02 g/L) em HHSM foi obtida maximizando a concentração de hidrolisado de farelo de soja (5,0 g/L). O pH, nos níveis estudados, não influenciou a solubilização da proteína de soja em HHSM. Pela RMS, o valor máximo para o fator de conversão de açúcares em etanol (0,20 g/g) pode ser alcançado empregando-se hidrolisado de farelo de soja em seu nível superior (5,0 g/L) e uréia (3 g/L) e sulfato de amônio (3,0 g/L) em seus pontos centrais. A fonte de proteína de farelo de soja solubilizada em HHSM tem potencial como fonte de nitrogênio alternativa na produção de bioetanol por Scheffersomyces stipitis. / The corn cob, due to its lignocellulosic structure, can be used as a biomass renewable source for soluble sugars can be converted into high value-added products, such as ethanol and others. Acid hydrolysis is the mostly used method to obtain hemicellulosic hydrolysate from lignocellulosic materials, leading to the obtaining of the xylose sugar at the highest concentration, from their hemicellulosic fraction. The xylose fermenting yeast Scheffersomyces stipitis is among the few organisms that utilize both xylose and glucose regulatory systems and exhibits a transition between the respiratory and fermentative processes. This work aims to contribute to the development of a technology to obtain bioethanol by Scheffersomyces stipitis CBS 6054, from the corn cob hemicellulosic fraction, evaluating the nutritional formulation of the fermentation medium. As an alternative of nitrogen source, it was chosen soybean bran. The corn cob hemicellulosic hydrolysate (HHSM) was obtained by acid hydrolysis, vacuum evaporated and treated by pH variation. Hydrolysate of soybean bran was obtained by enzymatic hydrolysis (Alcalase, 60°C, 100 rpm, 3h). The solubility evaluation of the hydrolysate of soybean bran in HHSM (pH 4.0 to 7.0) was performed by 22 full factorial design using response surface methodology (RSM). The supplementation of HHSM with solubilized soybean bran protein associated or not with other nutrients (urea and ammonium sulphate) to obtain bioethanol employed a 23 full factorial design using RSM. The fermentation was carried out in Erlenmeyer flasks (125 mL) containing 50mL of medium stirred at 150rpm and 30 °C. The inoculum concentration was 1.5 g/L of cells. The results showed that the acid hydrolysis favored removal of the hemicellulosic fraction (88.05%) with little change in cellulose (10.06%) and lignin (27.07%) compared to the in natura material, providing a hemicellulosic hydrolysate rich in xylose (28.30 g/L) with low concentrations of phenolics compounds and furans. Treatment of HHSM reduced protein content in the vaccum evaporated hydrolysate (74.76%) and original hydrolysate (28.53%). Soybean bran had good quality as shown by the protein solubility of KOH of 82.99 % and by urease index of 0.00. The soybean bran enzymatic hydrolysis produced 50.45% more protein than aqueous soybean bran protein extraction, yielding 45 g/L of solubilized protein. In the determination of protein content by the Lowry method was necessary to take into account the presence of interfering species of the HHSM. The maximum soybean bran protein solubility (9.01 g/L) was obtained maximizing the concentration of hydrolysate of soybean bran (5.0 g /L) in HHSM. In the range studied in this work, the pH did not influence the solubility of soybean bran protein in HHSM. For the response surface methodology, the maximum value for the ethanol yield (0.20 g/g.) can be achieved employing hydrolysate of soybean bran in its upper level (5.0 g/L) and urea (3 g/L) and ammonium sulfate (3 g/L) in their center points. The source of soybean bran protein solubilized in HHSM has potential as an alternative nitrogen source for bioethanol production by Scheffersomyces stipitis.