Dissertations / Theses on the topic 'Novozym'

Le biodiesel, consid??r?? comme une solution pour remplacer le p??trodiesel est un sujet de recherche mondial. Un des principaux probl??mes associ??s au d??veloppement industriel du biodiesel est la source de mati??re premi??re ainsi que le proc??d?? de transformation. Ainsi, la pr??sente ??tude a pour but de trouver une source de mati??re premi??re durable pour la production industrielle de biodiesel et de d??terminer le proc??d?? de transformation de la mati??re premi??re, le plus appropri??, ainsi que les meilleures conditions op??ratoires. Durant la premi??re ??tape de ce projet, une source de mati??re premi??re durable a ??t?? s??lectionn??e : les microalgues. Le proc??d?? de transformation ??tudi?? est la transest??rification enzymatique. L???huile d???olive, huile ayant une composition en acides gras similaires ?? celle de l???huile de la microalgue Chlorella protothecoides, a ??t?? choisie pour effectuer les r??actions. Pendant la deuxi??me ??tape, le proc??d?? de standardisation de la r??action (bior??acteur de 5 mL) consistait ?? faire varier : le type de catalyseur (lipases de Candida antarctica (Novozym?? 435) et de Thermomyces lanuginosus (TL I150)), la concentration du catalyseur (7 ?? 14 % m/mhuile), la temp??rature de r??action (25 ?? 50 ??C) et le ratio molaire alcool:huile (3:1 ?? 4:1) ; la vitesse d???agitation ??tant de 150 rpm pour toutes les r??actions. Des techniques d???optimisation telle que la preincubation de l???enzyme ont ??t?? ??galement essay??es. Le rendement en esters alkyliques de la r??action de transest??rification enzymatique de l???huile en fonction du temps est la variable de contr??le pour toutes les r??actions. La standardisation des variables du proc??d?? a ??t?? faite en fonction de la r??duction du temps de r??action et du rendement en esters alkyliques. Un rendement ??lev?? en esters alkyliques de 92 % (m/m) a ??t?? obtenu sous les conditions op??ratoires suivantes : une concentration de catalyseur (TL I150) de 7 % (m/mhuile), une temp??rature de r??action de 25 ??C, un ratio molaire alcool:huile de 3:1 et un temps de r??action de 4 h ; la lipase a ??t?? preincub??e pendant 6 h avant la r??action de transest??rification. Le temps de r??action, un des param??tres importants lors du proc??d?? de standardisation des variables, a ??t?? r??duit de 24 ?? 4 h. Un autre param??tre significatif de la r??action est la temp??rature : une temp??rature de 25 ??C a ??t?? utilis??e; cette temp??rature de r??action est faible et rend le proc??d?? au niveau industriel plus attrayant.

Le biodiesel, considéré comme une solution pour remplacer le pétrodiesel est un sujet de recherche mondial. Un des principaux problèmes associés au développement industriel du biodiesel est la source de matière première ainsi que le procédé de transformation. Ainsi, la présente étude a pour but de trouver une source de matière première durable pour la production industrielle de biodiesel et de déterminer le procédé de transformation de la matière première, le plus approprié, ainsi que les meilleures conditions opératoires. Durant la première étape de ce projet, une source de matière première durable a été sélectionnée : les microalgues. Le procédé de transformation étudié est la transestérification enzymatique. L’huile d’olive, huile ayant une composition en acides gras similaires à celle de l’huile de la microalgue Chlorella protothecoides, a été choisie pour effectuer les réactions. Pendant la deuxième étape, le procédé de standardisation de la réaction (bioréacteur de 5 mL) consistait à faire varier : le type de catalyseur (lipases de Candida antarctica (Novozym® 435) et de Thermomyces lanuginosus (TL I150)), la concentration du catalyseur (7 à 14 % m/mhuile), la température de réaction (25 à 50 °C) et le ratio molaire alcool:huile (3:1 à 4:1) ; la vitesse d’agitation étant de 150 rpm pour toutes les réactions. Des techniques d’optimisation telle que la preincubation de l’enzyme ont été également essayées. Le rendement en esters alkyliques de la réaction de transestérification enzymatique de l’huile en fonction du temps est la variable de contrôle pour toutes les réactions. La standardisation des variables du procédé a été faite en fonction de la réduction du temps de réaction et du rendement en esters alkyliques. Un rendement élevé en esters alkyliques de 92 % (m/m) a été obtenu sous les conditions opératoires suivantes : une concentration de catalyseur (TL I150) de 7 % (m/mhuile), une température de réaction de 25 °C, un ratio molaire alcool:huile de 3:1 et un temps de réaction de 4 h ; la lipase a été preincubée pendant 6 h avant la réaction de transestérification. Le temps de réaction, un des paramètres importants lors du procédé de standardisation des variables, a été réduit de 24 à 4 h. Un autre paramètre significatif de la réaction est la température : une température de 25 °C a été utilisée; cette température de réaction est faible et rend le procédé au niveau industriel plus attrayant.

Une voie d'accès aux cires est proposée et évaluée par catalyse enzymatique. Elle s'effectue à partir d'un mélange d'esters méthyliques (colza/tournesol) et d'alcool stéarique via une réaction de transestérification en présence de Lipozyme. L'originalité de ces travaux réside dans la simple mise en oeuvre des substrats et de l'enzyme immobilisée en réacteur contrôlé en température sans addition de solvant organique. L'obtention de rendements élevés est réalisée avec une faible quantité d'enzyme, des taux de conversion de 80 à 100 %, suivant le rapport molaire des substrats sont obtenus en 2 heures à 60 °C. L'influence du rapport molaire 1 oléate de méthyle : alcool stéarique 1 ainsi que de la température sont étudiés et donnent des valeurs optimales pour le ratio 1 1 : 0,5 1 à 60 °C. L'effet inhibiteur de l'alcool stéarique a été mis en évidence par une étude cinétique. La présence de limitations diffusionnelles de type externes a été montrée (milieu réactionnel/surface du support enzymatique). Après l'évaluation, l'optimisation de la mise en oeuvre a permis de faire progresser les performances. La validation du procédé a été vérifiée à plus grande échelle. Une autre enzyme immobilisée a été testée, le Novozym, qui permet d'obtenir un rendement optimal pour le mélange équimolaire. Cet avantage conduit à un produit exempt de substrat en fin de réaction. De plus, l'efficacité catalytique du Novozym (0,213 miri-1) est supérieure à celle du Lipozyme (0,144 miri ). Enfin, la réaction de transestérification a été examinée avec élimination simultanée du co-produit, le méthanol, au fur et à mesure de sa formation. Les deux préparations enzymatiques ont été testées en réacteurs fermé, ouvert et sous vide. Quelque soient les conditions, la réaction a'alcoolyse est plus rapide si le méthanol produit pendant la réaction est retiré du mélange. L'utilisation des ratios S1/S2=1 convient à un procédé particulièrement simple puisqu'il amène une production de cire exempte de co-substrat
Wax ester production has been investigated. Transesterification reaction has been realized from methyl ester mix (vegetable oils of rape and sunflower) and stearyl alcohol with Lipozyme. The alcoholysis reaction is controlled in solvent-free medium that is exclusively composed of the reactants and the enzyme. The transesterification is performed by simply mixing the two substrates in a temperature-controlled water bath under stirring. High yields are obtained with a Iow amount of Lipozyme, rate conversion from 80 to 100 % depending on molar ratio in 2 hours at the temperature of 60 °C. The balance between optimal working temperature and the molar ratio of substrates in such a complex medium appears to be 60 °C with a molar ratio I methyl oleate : stearyl alcohol of I 1: 0,5I. Substrate inhibition due to stearyl alcohol has been confirmed by a study of kinetic parameters. More, external diffusional limitations have been showed (reaction medium/surface of enzymatic support). Then, after evaluation, optimization of process has been performed. The validation of results has been verified at a large-scale process. Another enzymatic preparation has been tested. Novozym permits to obtain optimal yield for the equimolar mixing. This advantage directly led to a final product exempted of substrates. More, catalytic efficiency of Novozym (0,213 min-1) is higher than catalytic efficiency of Lipozyme (0,144 min-1). Finally, transesterification reaction has been examined with the elimination of the co-product formed, the methanol in proportion of producing. The two immobilised enzymes have been investigated in covered reactor, cap-opened reactor and under vacuum. More rapid is the methanol elimination, higher is the rate production of stearyl oleate. The use of substrate ratio S 1/Sz=l leads to direct stearyl waxes production exempted from reactive using simple but efficient way

De flerumettede omega-3 fettsyrene eikosapentaensyre (EPA) og dokosaheksaensyre (DHA) har fått økt oppmerksomhet på grunn av dokumenterte helseeffekter mot hjerte- og karsykdommer. Fettsyrene finnes normalt som etylestere eller triasylglyseroler i oppkonsentrerte fiskeolje produkter. Industrielt produseres fiskeolje produkter ved kjemisk transesterifisering, en prosess som krever høy temperatur og bruk av kjemikalier. Lipaser har i nyere tid fått gradvis økt oppmerksomhet på grunn av deres milde betingelser og spesifisitet ved bruk som biokatalysator under lipid modifikasjon. Denne oppgaven har som hovedformål å studere muligheten for å benytte lipase som biokatalysator ved transesterifiseringsreaksjon av sild- og selolje for produksjon av etylester. Den ikke-spesifikke immobiliserte lipasen Candida antarctica (Novozym 435) er benyttet som biokatalysator for reaksjonen. Reaksjonens progresjon er studert ved bruk av kjernemagnetisk resonans(13C NMR) som etter min beste kjennskap ikke er benyttet i stor grad for studie av etanollyse. Fettsyresammensetningen og fettsyreposisjoneringen på glyserolmolekylet til sild- og selolje er bestemt ved gasskromatografi (GC) og 13C NMR. Temperatur og etanolmengdens innvirkning og optimale betingelser er bestemt ved tynnsjiktkromatografi med flammeioniseringsdetektor (TLC-FID). I sild- og selolje utgjør enumettede fettsyrer den største andelen fettsyrer med henholdsvis 59 og 59% av totale mengde fettsyrer. De flerumettede omega-3 fettsyrene utgjør henholdsvis 16 og 23% for sild- og selolje. Selolje har fettsyrene EPA og DHA esterifisert til sn-1,3 posisjon ved >95%. Sildeolje har DHA esterifisert til sn-2 posisjon ved >95% og EPA esterifisert 49% til posisjon sn-1,3 og 51% til posisjon sn-2. Optimale reaksjonsbetingelser er funnet for etanollysereaksjonen med hensyn til temperatur og etanolmengde. Ved bruk av sildolje under støkiometrisk molarforhold etanol til olje er økende temperatur funnet å øke etylester dannelseshastigheten. Det er vist at 60oC gir en lavere reaksjonshastighet enn optimaltemperaturen 50oC. Dette kan forklares av redusert lipaseaktivitet som resultat av massetransportbegrensninger. Etanolmengdens innvirkning på etanollyse reaksjonen er funnet å gi økt etylester dannelseshastighet, ved økt mengde av etanol i systemet. Ved overskudd av etanol er det funnet at temperaturen ikke har samme innvirkning, som under støkiometrisk molarforhold etanol til olje. På bakgrunn av disse resultatene er 50oC funnet å være optimaltemperatur ved støkiometrisk molarforhold etanol. Ved overskudd av etanol er funnet at 30oC er den mest passende temperatur. 13C NMR er den eneste analysemetoden som gir multi-komponent informasjon i et steg. I denne oppgaven er teknikken benyttet for analyse av reaksjonsprogresjonen til etanollysereaksjonen under de optimaliserte betingelsene. Ved støkiometrisk molarforhold etanol til olje viser lipasen spesifisitet mot sn-1,3 posisjonene på glyserolmolekylet i sild- og selolje. For selolje viser lipasen høyere aktivitet mot fettsyren EPA enn DHA. Undersøkelsen gjort ved 50oC viser endring i sammensetningen asylglyserol gjennom reaksjonsforløpet fra 2MAG og 1,2DAG til 1MAG og 1,3DAG som kan forklares av intramolekylær asylmigrering. Analyse av reaksjonsprogresjonen til etanollysereaksjonen utført med overskudd av etanol og 30oC viser at lipasen fortsatt uttrykker spesifisitet mot sn-1,3 posisjonene på glyserolmolekylet. For selolje viser lipasen også økt aktivitet mot fettsyren EPA sammenlignet med DHA. Analysen viser imidlertid ikke endring i sammensetning asylglyseroler over reaksjonsforløpet noe som tilsier at det ved lavere temperatur ikke forekommer intramolekylær asylmigrering.

Mestrado em Engenharia Alimentar / Instituto Superior de Agronomia. Universidade de Lisboa
O presente estudo teve como objetivo produzir lípidos dietéticos do tipo MLM, por catálise enzimática, a partir de óleo de bagaço de azeitona bruto (OBA), de elevada acidez (20,2%), com teores elevados de produtos de oxidação (K232: 6,98 e K270:2,22) e de clorofilas totais (91 mg/kg feofitina a). Os MLM são triacilgliceróis (TAG) que contêm ácidos gordos de cadeia longa (L) em posição sn-2 e ácidos gordos de cadeia média (M) nas posições sn-1,3. Os MLM foram obtidos por acidólise de OBA com ácido caprílico (C8:0) ou cáprico (C10:0). As reações decorreram em descontínuo, em meio livre de solvente, razão molar de 1:2 (OBA:M), a 50 ºC durante 48 h. Utilizou-se como fonte de ácidos gordos de cadeia longa o OBA bruto e após remoção, por adsorção, de 99% de pigmentos clorofilinos. Testaram-se como biocatalisadores as lipases imobilizadas comerciais de Rhizomucor miehei (Lipozyme RM IM) (sn-1,3 seletiva) e de Candida antarctica (Novozym 435), e lipases comerciais líquidas (Novozym 388, Lipozyme CALB L e Novozym 735) por nós imobilizadas nos suportes sintéticos Lewatit VP OC 1600 e Accurel MP 1000. A Lipozyme RM IM e Novozym 435 catalisaram preferencialmente a formação de novos TAG com C10:0 em detrimento de C8:0, com rendimento em novos TAG de 56,6% (m/m) e 48,7% (m/m) a partir do óleo bruto e óleo descorado, respetivamente, por ação da Lipozyme RM IM, 52,5% (m/m) e 53,6% (m/m) a partir de óleo bruto e descorado, respetivamente, por ação de Novozym 435. O rendimento em novos TAG (%) obtidos por acidólise catalisada por Novozym 435 diminuiu com o aumento de temperatura (60 ºC). Os rendimentos em novos TAG obtidos por acidólise catalisada pelas lipases imobilizadas no laboratório foram inferiores a 12,6%
N/A

Ce travail a eu pour objectif de déterminer les conditions optimales de production d’un caroténoïde original, la torularhodine, par Sporobolomyces ruberrimus, cultivée en réacteur discontinu. Cette souche est capable d’utiliser le glycérol technique comme source de carbone et d’énergie pour sa croissance et pour la production de caroténoïdes. D’abord, il s’est agi d’identifier les facteurs opératoires majeurs qui sont susceptibles d’avoir une influence sur la production de la torularhodine, au travers d’une étude préliminaire. L’identification expérimentale de ces facteurs d’action - la température, le taux d’oxygène dissous et la supplémentation en acide oléique - a été validée statistiquement, à des degrés divers, avant d’engager une étape d’optimisation par la construction d’un plan d’expériences multicritère. Celui-ci a conduit à l’établissement de modèles polynômiaux du second degré pour représenter l’effet conjugué des facteurs retenus et permettre la prédiction des valeurs de µmax et de concentration de torularhodine rapportée à la biomasse. Cette étude a alors été consacrée à un essai de fonctionnalisation de la torularhodine, à partir de sa fonction carboxylique, en vue de la stabilisation de la molécule dont l’activité antioxydante est élevée. L’acylation enzymatique de la lysine par la torularhodine a été envisagée. Les conditions d’acylation par la lipase B de C. antarctica ont été déterminées avec un caroténoïde modèle, la bixine. Le produit dérivé obtenu après transacylation a été purifié et a montré une activité antiradicalaire supérieure à celle de la bixine. Ces résultats permettent d’envisager la synthèse de peptides acylés avec ce type de caroténoïdes
The aim of this work was to determine the optimum of an original carotenoid, the torularhodin, produced by Sporobolomyces ruberrimus, in batch culture. A very interesting characteristic of this strain is its ability to consume raw glycerol as a carbon and energy source for microbial growth and carotenoid production. In the fist part of this study, the identification of operating parameters that have an influence on the optimum torularhodin production, was achieved. Experimental assays reinforced by a statistical study allowed to identify temperature, dissolved oxygen pressure and oleic acid supplementation, as the major parameters of influence, and then the integration of these data was performed for the construction of a multiobjective optimization based on a multicriteria experimental design. The establishment of a mathematical model of a second degree polynomial type was developed for the prediction of the values of µmax and of the torularhodin concentration reported to biomass. In the last part, considering that torularhodin has an important antioxidant property and it exhibits a free carboxyl acid function which can be used as acyl agent, a study of its structure modifying by an enzymatic way as a stabilization pattern was started. The experimental conditions of lysine acylation by the lipase B of Candida antarctica were determined using a model carotenoid, the bixin. The resulting product of the synthesis of bixin derivative was purified and showed an antiradical activity of 2.5 times higher than that of bixin. This result showed the ability of the acylation reaction of peptides with this kind of carotenoids

L'objectif de cette thèse a été la synthèse par voie enzymatique de polyesters biodégradables à partir de ressources renouvelables provenant de productions d'oléagineux: le glycérol et le diacide oléique (D18 :1). Pour résoudre le problème économique lié au coût du biocatalyseur le plus efficace en polyestérification, la lipase immobilisée de Candida antarctica B (Novozym 435), de nouvelles lipases d'origine microbienne ont été recherchées dans des litières d'espèces végétales méditerranéennes. Dans ce but, a été développée une méthodologie permettant de mesurer le potentiel de synthèse d'enzymes lipolytiques, produites par des micro-organismes dégradant un polyester naturel, la cutine des feuilles. Une bactérie thermophile (BT2) a ainsi été sélectionnée parmi les souches isolées. Sa capacité à catalyser des polyestérifications a été évaluée et comparée à celle du Novozym 435. Ce dernier a été aussi utilisé pour mettre au point un système de synthèse en milieu fondu. Il a permis l'obtention d'un élastomère ayant un poids moléculaire supérieur à 134 kDa. Des mesures de biodégradabilité ont montré que ce polyester produit par voie enzymatique se minéralisé plus vite que des polyesters produits par chauffage à 160°C et 180°C. L'impact de la teneur en eau, du ratio molaire glycéroVacide, de la quantité d'enzyme dans le milieu réactionnel a été analysé
The aim of this thesis has been the enzymatic synthesis of biodegradable polyesters from renewable resources issued from oleaginous plants: glycerol and di-oleic acid. To work out the economical problem, due to the cost of the most efficacious bio-catalyser for polyesterification, the immobilised lipase of Candida antarctica B (Novozym 435), new microbial lipases has been researched in litters of Mediterranean plant species. With this object, a new methodology has been developed allowing to measure the potentialities of lipolytic enzymes to synthesise polyesters. These enzymes has been produced by micro-organisms able to degrade a natural polyester, the cutin. A thermophilic bacterium (BT2) has been selected among the isolated strains. Their capabilities to catalyse polyesterifications has been evaluated and compared to those of Novozym 435. This last bio-catalyser has also been used to study an apparatus to synthesise polyesters in bulk. In this conditions, an elastomer product was obtained with a molecular weight higher than 134 kDa. Biodegradability measures have shown that this polyester is faster mineralised than polyesters produced by heating from 160°C up to 180°C. The impact, of the a[w], molar ratio glycerol/acid and enzyme quantity in the reacting medium, on the yield and on the molecular weight of the polyesters formed has been studied

O objetivo desta dissertaÃÃo foi sintetizar derivados de vitamina A por rota enzimÃtica, como alternativa à rota quÃmica, que à caracteristicamente mais agressiva ao meio ambiente. A sÃntese do palmitato de retinila resultaria em produto com melhor aceitaÃÃo de mercado, jà que à mais estÃvel do que o Ãster que foi utilizado como substrato, acetato de retinila. Jà a sÃntese de adipato de retinila, tinha como principal finalidade, disponibilizar um novo derivado de vitamina A. Para ambos, visava-se a aplicaÃÃo nas indÃstrias farmacÃutica, cosmÃtica e alimentÃcia. Nesse contexto, utilizou-se lipase de Candida antarctica tipo B imobilizada (Novozyme 435 com 571,48 UI/g  55,47) e os substratos acetato de retinila, Ãcidos palmÃtico e adÃpico. AlÃm destes, peneira molecular (PM) 3Ǻ tambÃm foi adicionada, jà que as reaÃÃes propostas liberam Ãgua para o meio reacional, desfavoredendo a sÃntese do Ãster desejado. Dois planejamentos foram realizados para se avaliar a sÃntese de palmitato de retinila, ambos em volume reacional total de 2 mL. No primeiro, trÃs variÃveis foram analisadas: proporÃÃo entre os substratos, solvente e temperatura. A quantidade de acetato de retinila foi mantida em 0,1 mmol e a do Ãcido palmÃtico variando entre 0,1 e 0,5 mmol. Levando em consideraÃÃo o coeficiente de partiÃÃo do Ãcido utilizado, foram testados tolueno e hexano. As temperaturas variaram entre 25 e 40ÂC, de acordo com o planejamento fatorial 23 blocado com ponto central. No segundo, estudou-se a influÃncia da quantidade de lipase (25, 50 e 75 mg) e PM (20, 50, 80 mg) em tolueno e hexano, conforme planejamento fatorial 32. Ensaios em maior escala foram realizados nÃo apenas para o palmitato, o qual foi submetido a teste de estabilidade tÃrmica, mas tambÃm para o adipato, que por nÃo ser comercializado precisou ser separado da reaÃÃo e identificado por ressonÃncia magnÃtica nuclear. Com uma anÃlise estatÃstica dos resultados, pÃde-se observar que os parÃmetros que tiveram efeito significativo no primeiro planejamento, foram a temperatura e a interaÃÃo desta com a razÃo molar entre os substratos. No segundo, tanto a enzima como a relaÃÃo quadrÃtica da PM foram significantes no rendimento de sÃntese com tolueno, e apenas a enzima, quando utilizado o hexano. A separaÃÃo do palmitato de retinila foi realizada em coluna de sÃlica C18, tendo sido avaliada em calorimetria exploratÃria diferencial (do inglÃs, differencial screening calorimetry - DSC) e observado eventos tÃrmicos por volta de 6,54ÂC. Quanto ao adipato de retinila, nenhum procedimento de separaÃÃo foi eficaz para a separaÃÃo da mistura formada entre o mesmo e o adipato de diretinila.
The main objective of this work was to synthesize vitamin A derivatives through an enzymatic route, as an alternative to chemistry route, more aggressive to the environment. The conversion of retinyl acetate into retinyl palmitate would result in a product with better market acceptance, since it is more stable than the ester used as substrate. Retinyl adipate synthesis, on the other hand, was studied in order to prepare a new vitamin A derivative. Both Vitamin A derivatives synthesized in this work were aiming the industrial production of cosmetics and foods. In this context, immobilized Candida antarctica type B lipase (Novozyme 435 with 571,48 UI/g  55,47) was used to catalyze the conversion of the substrates retinyl acetate, palmitic and adipic acids. In addition to these, molecular sieves was also added since the proposed reactions release water to the reaction media, which is not favorable to the desired ester synthesis. The retinyl palmitate synthesis was investigated by two factorial experimental design, using a total reactional volume of 2 mL. In the first, three variables were analyzed: rate between substrates, type of solvent and temperature. Retinyl acetate was kept in 0,1 mmol and palmitic acid varied between 0,1 and 0,5 mmol. Considering the acid partition coefficient, toluene and hexane were tested as solvents. The temperatures varied between 25 and 40ÂC, following a 23 factorial experimental design blocked with central points. In the second design, the influence of lipase (25, 50 e 75 mg) and molecular sieves (20, 50, 80 mg) amounts were studied using toluene or hexane as solvent, in accordance with a 32 factorial design. Experiments in a larger scale were performed not only to the produce retinyl palmitate, which was submitted to termic stability tests, but also to retinyl adipate, which is not commercially available and thereof it was recovered from the reactional media and identified by nuclear magnetic resonance. The statistical analysis of the results allowed the observation of significant effects. In the first planning, temperature and their interaction with the molar rate between the substrates were the significant variables. In the second, enzyme and the molecular sieves quadratic relation were significant in the yield of synthesis with toluene, but only the enzyme was significant when hexane was utilized. The retinyl palmitate separation was performed in silica C18 column and the purified sample was analyzed by differential scanning calorimetric â DS with a thermal event around 6.54ÂC. In the case of retinyl adipate, no separation procedure was effective since there is a mixture formed between retinyl and diretinyl adipates.

SIQUEIRA, A. K. P. B. Síntese de derivados de vitamina A utilizando lipase de Candida antartica imobilizada (Novozyme 435). 93 f. 2007. Dissertação (Mestrado em Engenharia Química) – Centro de Tecnologia, Universidade Federal do Ceará, Fortaleza, 2007.
Submitted by Marlene Sousa (mmarlene@ufc.br) on 2016-03-22T11:56:23Z No. of bitstreams: 1 2007_dis_akpbsiqueira.pdf: 2640363 bytes, checksum: 7ea1a23b71959517bd2e732af8b11303 (MD5)
Approved for entry into archive by Marlene Sousa(mmarlene@ufc.br) on 2016-03-28T18:24:03Z (GMT) No. of bitstreams: 1 2007_dis_akpbsiqueira.pdf: 2640363 bytes, checksum: 7ea1a23b71959517bd2e732af8b11303 (MD5)
Made available in DSpace on 2016-03-28T18:24:03Z (GMT). No. of bitstreams: 1 2007_dis_akpbsiqueira.pdf: 2640363 bytes, checksum: 7ea1a23b71959517bd2e732af8b11303 (MD5) Previous issue date: 2007-08-31
The main objective of this work was to synthesize vitamin A derivatives through an enzymatic route, as an alternative to chemistry route, more aggressive to the environment. The conversion of retinyl acetate into retinyl palmitate would result in a product with better market acceptance, since it is more stable than the ester used as substrate. Retinyl adipate synthesis, on the other hand, was studied in order to prepare a new vitamin A derivative. Both Vitamin A derivatives synthesized in this work were aiming the industrial production of cosmetics and foods. In this context, immobilized Candida antarctica type B lipase (Novozyme 435 with 571,48 UI/g ± 55,47) was used to catalyze the conversion of the substrates retinyl acetate, palmitic and adipic acids. In addition to these, molecular sieves was also added since the proposed reactions release water to the reaction media, which is not favorable to the desired ester synthesis. The retinyl palmitate synthesis was investigated by two factorial experimental design, using a total reactional volume of 2 mL. In the first, three variables were analyzed: rate between substrates, type of solvent and temperature. Retinyl acetate was kept in 0,1 mmol and palmitic acid varied between 0,1 and 0,5 mmol. Considering the acid partition coefficient, toluene and hexane were tested as solvents. The temperatures varied between 25 and 40°C, following a 23 factorial experimental design blocked with central points. In the second design, the influence of lipase (25, 50 e 75 mg) and molecular sieves (20, 50, 80 mg) amounts were studied using toluene or hexane as solvent, in accordance with a 32 factorial design. Experiments in a larger scale were performed not only to the produce retinyl palmitate, which was submitted to termic stability tests, but also to retinyl adipate, which is not commercially available and thereof it was recovered from the reactional media and identified by nuclear magnetic resonance. The statistical analysis of the results allowed the observation of significant effects. In the first planning, temperature and their interaction with the molar rate between the substrates were the significant variables. In the second, enzyme and the molecular sieves quadratic relation were significant in the yield of synthesis with toluene, but only the enzyme was significant when hexane was utilized. The retinyl palmitate separation was performed in silica C18 column and the purified sample was analyzed by differential scanning calorimetric – DS with a thermal event around 6.54ºC. In the case of retinyl adipate, no separation procedure was effective since there is a mixture formed between retinyl and diretinyl adipates.
O objetivo desta dissertação foi sintetizar derivados de vitamina A por rota enzimática, como alternativa à rota química, que é caracteristicamente mais agressiva ao meio ambiente. A síntese do palmitato de retinila resultaria em produto com melhor aceitação de mercado, já que é mais estável do que o éster que foi utilizado como substrato, acetato de retinila. Já a síntese de adipato de retinila, tinha como principal finalidade, disponibilizar um novo derivado de vitamina A. Para ambos, visava-se a aplicação nas indústrias farmacêutica, cosmética e alimentícia. Nesse contexto, utilizou-se lipase de Candida antarctica tipo B imobilizada (Novozyme 435 com 571,48 UI/g ± 55,47) e os substratos acetato de retinila, ácidos palmítico e adípico. Além destes, peneira molecular (PM) 3Ǻ também foi adicionada, já que as reações propostas liberam água para o meio reacional, desfavoredendo a síntese do éster desejado. Dois planejamentos foram realizados para se avaliar a síntese de palmitato de retinila, ambos em volume reacional total de 2 mL. No primeiro, três variáveis foram analisadas: proporção entre os substratos, solvente e temperatura. A quantidade de acetato de retinila foi mantida em 0,1 mmol e a do ácido palmítico variando entre 0,1 e 0,5 mmol. Levando em consideração o coeficiente de partição do ácido utilizado, foram testados tolueno e hexano. As temperaturas variaram entre 25 e 40°C, de acordo com o planejamento fatorial 23 blocado com ponto central. No segundo, estudou-se a influência da quantidade de lipase (25, 50 e 75 mg) e PM (20, 50, 80 mg) em tolueno e hexano, conforme planejamento fatorial 32. Ensaios em maior escala foram realizados não apenas para o palmitato, o qual foi submetido a teste de estabilidade térmica, mas também para o adipato, que por não ser comercializado precisou ser separado da reação e identificado por ressonância magnética nuclear. Com uma análise estatística dos resultados, pôde-se observar que os parâmetros que tiveram efeito significativo no primeiro planejamento, foram a temperatura e a interação desta com a razão molar entre os substratos. No segundo, tanto a enzima como a relação quadrática da PM foram significantes no rendimento de síntese com tolueno, e apenas a enzima, quando utilizado o hexano. A separação do palmitato de retinila foi realizada em coluna de sílica C18, tendo sido avaliada em calorimetria exploratória diferencial (do inglês, differencial screening calorimetry - DSC) e observado eventos térmicos por volta de 6,54ºC. Quanto ao adipato de retinila, nenhum procedimento de separação foi eficaz para a separação da mistura formada entre o mesmo e o adipato de diretinila.

Process options to minimise the environmental impact and improve the efficiency of biodiesel production have been investigated. The process options considered include the use of heterogeneous catalysts and used cooking oil (UCO). An esterification pre-treatment reaction was investigated using an ion-exchange resin (Purolite D5082) and an immobilised enzyme (Novozyme 435). Another immobilised enzyme (Amano Lipase PS-IM) was investigated for transesterification. The fresh and used catalysts have been characterised. The catalytic activity of Purolite D5082, Novozyme 435 and Amano Lipase PS-IM have been investigated using a jacketed batch reactor with a reflux condenser. Purolite D5082 has been developed for the esterification pre-treatment process and is not commercially available. Novozyme 435 has been shown to be an effective esterification catalyst for materials with high concentrations of free fatty acid but it has not been investigated for the esterification pre-treatment reaction. It was found that a high conversion was possible with both catalysts. The optimum reaction conditions identified for Purolite D5081 were a temperature of 60 C, a methanol to free fatty acid (FFA) mole ratio of 62:1, a catalyst loading of 5 wt% resulting in a FFAs conversion of 88% after 8 h of reaction time. The optimum conditions identified for Novozyme 435 were a temperature of 50 C, a methanol to FFA mole ratio of 6.2:1 and a catalyst loading of 1 wt% resulting in a conversion of 90% after 8 h of reaction time. These catalysts were compared to previously investigated Purolite D5081 and it was found that the highest conversion of 97% was achieved using Purolite D5081, however there were benefits to using Novozyme 435 because the reaction could be carried out using a much lower mole ratio, at a lower temperature and in much shorter reaction time. During the Novozyme 435 catalysed esterification pre-treatment reactions it was found that the amount of free fatty acid methyl esters (FAME) formed during the reaction was greater than the amount of FFAs consumed. In order to investigate further an ultra-performance liquid chromatography mass spectrometry (UPLC-MS) method was developed to monitor the monogclyeride (MG), diglyceride (DG) and triglyceride (TG) concentrations. This analytical method was used to show that Novozyme 435 would catalyse the esterification of FFAs as well as the transesterification of MGs and DGs typically found in UCO. With the UPLC-MS method it was possible to separate the 1, 2 and 1, 3 DG positional isomers and from this it could be seen that the 1, 3 isomer reacted more readily than the 1, 2 isomer. The results from the UPLC-MS method were combined with a kinetic model to investigate the reaction mechanism. The kinetic model indicated that the reaction progressed with the sequential hydrolysis esterification reactions in parallel with transesterification. Commercially available Amano Lipase PS-IM was investigated for the transesterification reaction. Enzymes are not affected by FFAs and as a result the optimisation was carried out with UCO as the raw material. An optimisation study for the transesterification of UCO with Amano Lipase PS-IM has not previously been reported. The conditions identified for the Amano Lipase PS-IM catalysed transesterification step are addition of 5 vol% water, a temperature of 30 C, a methanol to UCO mole ratio of 3:1 and a catalyst loading of 0.789 wt% resulting in a TG conversion of 43%. An overall enzyme catalysed process was proposed consisting of Amano Lipase PS-IM catalysed transesterification (stage 1) followed by Novozyme 435 catalysed esterification (stage 2). The previously identified optimum conditions identified for each catalyst were used for above stages. It was found that when the oil layer from stage 1 was dried the final TG conversion was 55%.

Práca sa zaoberá problematikou globálnych distribučných systémov a ich využitím v cestovnom ruchu. V úvode popisuje historické skutočnosti vzniku a podmienky vývoja. Jadro práce sa venuje rozboru portfólia produktov distribučných systémov a následne poukazuje na ich vplyv na leteckú dopravu. V závere sú načrtnuté možné smery vývoja týchto systémov.

Práca sa zaoberá problematikou globálnych distribučných systémov a ich využitím v cestovnom ruchu. V úvode popisuje historické skutočnosti vzniku a podmienky vývoja. Jadro práce sa venuje rozboru portfólia produktov distribučných systémov a následne poukazuje na ich vplyv na leteckú dopravu. V závere sú načrtnuté možné smery vývoja týchto systémov.

L'utilisation de polymères biodégradables synthétiques connaît un grand essor depuis une dizaine d'années. Parmi ces polymères, les polyesters occupent une place privilégiée car ils sont biocompatibles : ils sont d'origine naturelle ou d'origine synthétique. Dans tous les cas, on peut les préparer par polymérisation par ouverture de cycle (ROP) à partir de lactones1.
L'utilisation des lactones est parfois limitée à cause de leur faible polymérisabilité. Cette dernière est contournée par l'utilisation de systèmes catalytiques très réactifs souvent à base de métaux qui ne sont pas toujours compatibles avec une application en biologie (pharmacologie, environnement)2. Une approche pour pallier ce problème consiste à activer ‘chimiquement' ces monomères pour en tirer un avantage dans le processus de polymérisation. Le L-lacOCA est ainsi un analogue du L-lactide qui possède une fonction O-carboxyanhydride (OCA). Ce monomère est beaucoup plus réactif que la dilactone cyclique équivalente : il polymérise de façon contrôlée et vivante dans des conditions catalytiques plus douces3.
Ce travail commence par une étude théorique de la ROP du L-lacOCA et du L-lactide catalysée par la 4-diméthylaminopyridine (DMAP) et en présence d'un alcool. Le mécanisme de la polymérisation ainsi révélé consiste en une activation basique de l'amorceur par la DMAP. Pour ce catalyseur, il y a mise en évidence pour la première fois d'un mode d'action bifonctionnel inusuel qui met en jeu une liaison hydrogène de faible énergie4.
La deuxième partie du manuscrit décrit le développement de la ROP du L-lacOCA avec un systême catalytique alternatif écocompatible : la catalyse enzymatique. Jusqu'à maintenant, les enzymes réalisent difficilement la ROP du lactide. Avec deux lipases, la Novozyme 435 et la lipase PS, il a été possible d'obtenir du polylactide de haut poids moléculaire à partir du monomère activé. Dans le cas de la Novozyme 435, la polymérisation est contrôlée et possède un caractère vivant.
Dans une dernière partie, nous avons essayé d'étendre le principe d'activation du motif OCA à d'autres monomères. Nous avons étudié la ROP des β-OCAs, les O-carboxyanhydrides à 6 chaînons qui pourraient donner accès aux polymères naturels comme le PHB. Trois monomères de ce type, le PivOCA, le MepOCA et le ButOCA ont été synthétisés. L'étude de leurs réactivités a mis en avant un problème de sélectivité entre les deux carbonyls du motif OCA lors d'une attaque nucléophile. A cause de réactions secondaires, les essais de ROP ont montré qu'il était difficile d'accéder proprement à des polyesters.
Références
1. Biopolymers, Wiley VCH, 2003, Vol. 3a-3b-4.
2. O. Dechy-Cabaret, B. Martin-Vaca, D. Bourissou, Chem. Rev., 2004 (104) 6147.
3. O. Thillaye du Boullay, E. Marchal, B. Martin-Vaca, F. P. Cossio and D. Bourissou., J. Am. Chem. Soc., 2006 (128) 16442.
4. C. Bonduelle, B. Martin-Vaca, F.P. Cossio, D. Bourissou, Chem. Eur. J., 2008 , 14, 5304.

This master’s thesis is aimed at process of enzymatic hydrolysis of lignocellulosic material – waste paper as a source of raw material for production of liquid biofuels. In the theoretical part of this work are summarized previously used methods of hydrolysis and lignocellulosic materials used for the process of hydrolysis as a source of fermentable sugars for fermentation technology. The different types of waste paper are evaluated from the composition and usability with consideration to the papermaking process in order to select the appropriate type of waste paper for the enzymatic hydrolysis process. In the next part of this work are suggested technological premises and procedures for the preparation of raw materials and the subsequent enzymatic hydrolysis of these pre–treated materials. In the experimental part were optimized parameters of enzymatic hydrolysis using the Novozymes company enzyme package. Enzymatic degradation of cellulose to reducing sugars was observed using Somogyi – Nelson method. For the verification of hydrolysis conditions were used model materials with high cellulose content – pulp and filter paper. Conditions, which seems to be the best after testing on the model materials, were verified on specific waste paper materials – offset cardboard, recycled paper, matte MYsol paper and for comparison again on model materials – pulp and filter paper. The highest yields was achieved with the use of cardboard, which was further tested using various combinations of pretreatment to material for purpose of increase the yields of hydrolysis.

Práca analyzuje dopad predstáv maďarských a slovenských politikov z obdobia Rakúska-Uhorska na povahu súčasných maďarsko-slovenských vzťahov vyznačujúcich sa vzájomnými rozpormi. Tieto rozpory vyplývajú na jednej strane z jednostranného chápania dejinných udalostí spejúcich k rozpadu monarchie, na druhej strane za nimi stojí pozostatok trianonského delenia Uhorska ? maďarská menšina na Slovensku. V piatich kapitolách sa práca postupne venuje nasledujúcim oblastiam: vplyvu minulosti na súčasné dianie, predstavám politikov predvojnového obdobia, vystúpeniam maďarskej a československej delegácie na parížskej mierovej konferencii, rezíduám trianonského usporiadania a súčasným maďarsko-slovenským medzištátnym vzťahom.

Mestrado em Engenharia do Ambiente
O crescente consumo de energia, bem como a possibilidade de esgotamento dos recursos não renováveis, tem fomentado a busca de fontes de energia alternativas. O biodiesel é um biocombustível obtido a partir de fontes renováveis e a sua utilização permite reduzir as emissões de gases com efeito de estufa. Nos últimos anos tem-se produzido biodiesel a partir de óleos alimentares usados (OAU), sendo que com esta aplicação valoriza-se um resíduo e simultaneamente produz-se um combustível “verde”. O biodiesel é produzido através das reações de transesterificação e/ou esterificação entre triglicerídeos e/ou ácidos gordos livres e um álcool, na presença de um catalisador. O rendimento do processo está estritamente relacionado com o tipo de catalisador e as condições que este opera. O principal objetivo do presente trabalho consistiu na avaliação do efeito de alguns parâmetros operacionais no desempenho de uma lípase imobilizada (Novozyme® 435), nomeadamente: (i) índice de acidez do óleo, (ii) razão mássica de enzima/óleo e (iii) método regeneração da enzima com vista à sua reutilização. Também foi objeto de estudo do presente trabalho a produção em contínuo, num (bior)reator tubular de leito fixo, de ésteres metílicos de ácidos gordos (FAME) usando a referida enzima. Registou-se um aumento rendimento em com o incremento do índice de acidez do óleo usado, o que indicia que a enzima catalisa simultaneamente as reações de esterificação e transesterificação. Relativamente à razão mássica de enzima/óleo, dentro da gama testada verificou-se um aumento do rendimento em FAME com a concentração da enzima em meio reacional. Dos vários solventes testados, a aplicação de solvente tert-butanol na regeneração (com incubação) da enzima foi o que melhores resultados teve. Finalmente, os resultados obtidos no ensaio de produção de FAME num biorreator contínuo são motivadores, criando expectativas de uma possível aplicação industrial no futuro.
The increasing energy consumption and the non-renewable resources depletion has encouraged the search for alternative energy sources. Biodiesel is a biofuel obtained from renewable sources which utilization allows aiming the reduction on greenhouse effect gases emissions. In the last few years, biodiesel has been produced from used cooking oil, since this application promotes the valorization of a waste and the production of a green fuel, simultaneously. Biodiesel is produced through transesterification reactions and/or esterification between triglycerides and/or fatty acids and an alcohol, in the presence of an appropriate catalyst. The efficiency of the process is strictly related with the type of catalyst and the operational conditions. The main goal of this study was to evaluate the effect of some operational parameters in an immobilized lipase’s performance (Novozyme® 435), namely: (i) oil’s acidity index, (ii) enzyme/oil mass ratio and (iii) applied treatment on the enzyme regeneration stage, in order to reutilize it. It was also a goal to study the production in a continuous regime, in a fixed bed bio(reactor), of fatty acid methyl esters (FAME) using the referred enzyme. It has been registered an increased efficiency on FAME with the oil acidity index rise, which indicates that the enzyme catalyzes simultaneously both the esterification and transesterification reactions. Concerning the enzyme/oil mass ratio , within the tested range, an increase was registered on FAME efficiency with enzyme concentration in the reactional medium. Among several solvents tested on enzyme washing, tert-butanol was the one with the better performance. Finally, the results obtained from the FAME production on a continuous bioreactor essay are motivating, creating some expectations on its possible future application at an industrial level.

Danas je gotovo nepoznat podatak da na katedrama za gudačke instrumente na akademijama umetnosti u regionu od ukupnog broja diplomiranih kadrova većinu čine žene. Otuda je vredna istraživačke pažnje analiza procesa obrazovanja i profesionalnog delovanja u njihovim sredinama tog značajnog broja muzički visoko obrazovanih žena. Upoređivanjem podataka iz tri akademske sredine jugoslovenskog prostora dolazimo do značajnih zaključaka za istoriju ženskog muzičkog nasleđa u regionu na ovom prostoru i za metodiku rada sa budućim kadrovima.Cilj istraživanja je prikupljanje, selekcija i interpretacija podataka o životu diplomiranih izvođačica na gudačkim instrumentima u Novom Sadu, Banjaluci i Zagrebu od osnivanja akademskih institucija do danas, kako bi se skrenula pažnja na pitanje konstruisanja identiteta izvođačica tokom i nakon visokog muzičkog obrazovanja.Hipoteza 1 je da značajan broj diplomiranih izvođačica na gudačkim instrumentima doprinosi promeni svesti o važnosti rodnog identiteta u muzičkoj umetnosti u regionu.Hipoteza 2 je da povećan broj diplomiranih izvođačica na gudačkim instrumentima ne doprinosi promeni svesti o važnosti rodnog identiteta u muzičkoj umetnosti u regionu.Hipoteza 3 je da je profesionalni identitet diplomiranih izvođačica na gudačkim instrumentima nadređen svim drugim komponentama identiteta, uključujući i rodni.Korpus obuhvata diplomirane muzičarke gudačkih instrumenata sa Akademije umetnosti u Novom Sadu (20), u Zagrebu (4)i u Banjaluci (8).Analiza 13 komponenata identiteta (detinjstvo, školovanje, devedesete godine 20. veka, brak, deca, maternji jezik, zatim nacionalni, verski, profesionalni identiteti, zdravlje, članstvo u strukovnim udruženjima i političkim strankama, hobi).Rezultati pokazuju da je prva hipoteza samo delimično tačna, te da je treća hipoteza tačna za ukupan uzorak: sve muzičarke prednost daju profesionalnom identitetu od ranog detinjstva. Empirijski podaci ne potvrđuju stereotip da profesija muzičarke i braka, porodice i dece ne idu zajedno.Rezultati istraživanja su važni koliko za novo sačinjavanje istorije muzike i žena u toj oblasti toliko i za rodne studije, koje se staraju za afirmaciju žena u različitim profesijama u današnjem vremenu. Posebno rezultati treba da obogate nastavnu i metodičku praksu u domenu muzike na svim nivoima obrazovanja kod nas. Podaci iz ovog rada bi mogli (zapravo, morali) da postanu deo udžbeničke literature. Na ovo se nadovezuju i podaci do kojih je došlo ovo istraživanje, a koji svedoče o tome da je u svetu i u regionu jugoslovenskog prostora značajan broj žena doprinosio i još uvek, možda i više nego ikada ranije, doprinosi razvoju muzike i muzičke kulture.
Today is almost unknown the fact that on the string department at the academies of arts in our region most of the graduated students are women. The analysis of this process is worth the research attention of education and professional activities of this, relatively significant number of graduated women string instrumentalists. By comparing data from three cultural backgrounds of ex-Yugoslav territory we come to significant conclusions for the history of women's musical heritage in the region in this area and the methodology of work with future personnel.The aim of the research is the collection, selection and interpretation of data about the life of graduated women performers on stringed instruments in Novi Sad, Banja Luka and Zagreb since the establishment of these academic institutions to present day, in order to draw attention to the issue of constructing identity of women performers during and after the higher music education.Hypothesis 1 is that a significant number of female music performance graduates on string instruments contributes to improving the awareness of the importance of gender identity in the music art in the region.Hypothesis 2 is that the increased number of female music performance graduates on string instruments does not contribute to improving the awareness of the importance of gender identity in the music art in the region.Hypothesis 3 that professional identity of the female music performance graduates on string instruments is superior to all other components of identity, including gender.The corpus includes female music performance graduates on string instruments from the Academy of Arts in Novi Sad (20), Zagreb (4) and Banja Luka (8).Analysis of the 13 components of identity (childhood, education, nineties of the 20th century, marriage, children, mother tongue, then national, religious, professional identities, health, membership in professional associations and political parties, hobbies).The results show that the first hypothesis is only partly true, and that the third hypothesis is true for the total sample: all the female musicians prefer the professional identity from early childhood. Empirical data do not confirm the stereotype that the profession of a female musician exclude marriage, family and children.The research results are as important as the new drafting history of music and women in this area so much and for gender studies, which are undertaken for the advancement of women in various professions in modern times. In particular, the results would enrich teaching and methodical practice in the field of music education at all levels in our country. Data from this study could (indeed, must) become a part of textbooks. In addition the data that occurred in this research testify to the fact that in the world and in the region Yugoslav territory a significant number of women contributed, and still, perhaps more than ever, contributes to the development of music and musical culture.

In the diploma thesis are discussed the process of enzymatic hydrolysis of waste paper as a source for the production of bioethanol by bacteria Zymomonas mobilis. In the theoretical part summarize basic information about particular methods of hydrolysis, about paper used as a raw material for enzymatic hydrolysis, about possibilities of the fermentative production of bioethanol focusing on the method of simultaneous saccharification and fermentation comparison with enzymatic hydrolysis and fermentation. Suitable microorganisms for ethanolic fermentation and simultaneous saccharification and fermentation and their advantages and disadvantages, are further discussed in this part as well. The theoretical part ends with the suggestion of the technological process for production of bioetanol. It covers all necessary steps from the input of raw material to the separation of produced ethanol. In the experimental part various parameters of hydrolysis, fermentation and simultaneous saccharification and fermentation were optimized using enzymes from Novozymes® company and the Zymomonas mobilis CCM2770 and Zymomonas mobilis LMG457 bacterium. The conversion rate of paper cellulose to gluckose and production of ethanol were observed by HPLC/RI method. Type of buffer, quantity of cells, enzyme and substrate were optimized in order to maximize the efficiency of the process. All experiments were performed on paper containing high amount of cellulose and for comparison on standard medium which contains gluckose. The highest yields was achieved with the use of Novozymes® Cellulosic ethanol enzyme Kit. The strain Zymomonas mobilis LMG457 has demonstrated as a better producer.

This thesis examines the place of the past within the lives and works of three notable Anglo-Norman authors of history: Eadmer of Canterbury, Symeon of Durham, and Orderic Vitalis of the monastery of Saint-Évroul in Normandy. The first half of the twelfth century witnessed an unprecedented flowering of historical writing in England and Normandy. Scholarly interest and debate surrounding the historical texts produced in this context, and in particular the reasons for their composition, has grown significantly in recent years. This thesis examines the place of Eadmer’s, Symeon’s and Orderic’s historical writings within the wider corpus of works which they are known to have studied and composed, according to surviving manuscript evidence. Particular attention is placed on: their engagement with wider themes of learning such as exegesis and theology, Latin poetry and computistical studies; their participation in the organisation of monastic and ecclesiastical life, including record-keeping, revision and care of book-collections and their role as monastic cantors; and their experiences of training in and engagement with historical studies and resultant self-identification as authors of history. This thesis will argue that although all three authors had access to a concise framework through which medieval audiences understood the nature and purposes of historical studies (as shown in chapters three and four) the exact character and intended purposes of their historical texts was in fact heavily dependent on the degree to which each author interacted with the wider textual culture of contemporary Benedictine studies (as outlined in chapters five, six and seven). Conclusions will observe that the three examples considered demonstrate the multifaceted nature of historical studies in the medieval period, and especially the overlap between the various sub-genres of history, such as narrative text, annal, chronicle, and hagiography, and also reveal the resonances of the past within almost every aspect of monastic life and studies in the period.

In diploma thesis the process of enzymatic hydrolysis of waste paper as a source for the production of liquid biofuels is discused. It follows directly the homonymous diploma thesis from Ing. Brummer, and it is based on the findings, which were solved and decided in previous work. In the theoretical part there is a summarization of basic information on the enzymatic hydrolysis of waste paper and the associated influences of various factors of the rate and degree of hydrolysis. Higher attention is paid to a waste cardboard and its pretreatment methods due to the maximalization of the yield of hydrolysis. The next part summarizes options of the fermentative production of biofuels, focusing on the method of simultaneous saccharification and fermentation, where the further appropriate organism for ethanol fermentation is discussed. The last part is about the technological process from the raw material input to the separation of ethanol. In the experimental section the pre-treatment of waste paper in order to maximize the efficiency of hydrolysis was examined. The best results were achieved using a vibratory mill. In addition, various parameters for simultaneous saccharification and fermentation were optimized using enzymes from Novozymes® company and the yeast Saccharomyces cerevisiae. The conversion rate of waste paper cellulose to reducing sugars was observed by spectrophotometric method by Somogyi - Nelson and the amount of produced ethanol was quantified using HPLC / RI. As a part of this thesis some conditions (amount of enzyme, substrate, nutrients, yeasts, temperature, pH, type of buffer) were optimized to maximize the effectiveness of the overall process. All experiments were carried out on corrugated cardboard, which was chosen as the most promising material for hydrolysis that was among the waste paper pulp in diploma thesis by Ing. Brummer.

Submitted by Cássio da Cruz Nogueira (cassionogueirakk@gmail.com) on 2017-02-13T14:32:46Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_EstudoMisturasEnzimas.pdf: 2710960 bytes, checksum: 1b18c9a8f74a5fcb6bcc5409ea90c5df (MD5)
Approved for entry into archive by Edisangela Bastos (edisangela@ufpa.br) on 2017-02-14T16:04:10Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_EstudoMisturasEnzimas.pdf: 2710960 bytes, checksum: 1b18c9a8f74a5fcb6bcc5409ea90c5df (MD5)
Made available in DSpace on 2017-02-14T16:04:10Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_EstudoMisturasEnzimas.pdf: 2710960 bytes, checksum: 1b18c9a8f74a5fcb6bcc5409ea90c5df (MD5) Previous issue date: 2015
Neste trabalho, propôs-se avaliar misturas de enzimas comerciais fornecidas pela Novozymes A/S. As enzimas utilizadas neste trabalho foram: complexo celulásico, xilanase, β-glucosidase, na produção de glicose a partir do bagaço de cana-de-açúcar submetido a tratamento alcalino com solução de hidróxido de sódio na temperatura ambiente, 70ºC, 90ºC e 120ºC. Os rendimentos do BCA em base seca após tratamento com solução de NaOH a 6% (m/v) foram de 30,64% ± 1,395 (PACTA), 44,00% ± 1,787 (PAC70), 65,91% ± 1,096 (PAC90), e 95,25% ± 1,461 (PAC120), respectivamente. Os teores de cinzas para o BCA foram de 2,05% ± 0,027 (PACTA), 0,62% ± 0,013 (PAC70), 0,48% ± 0,007 (PAC90) e 0,18% ± 0,008 (PAC120). Os teores de lignina foram de 20,67 ± 0,603 (PACTA), 13,03 ± 0,711 (PAC70), 6,05 ± 0,196 (PAC90) e 5,49 ± 0,151 (PAC120). Os rendimentos da fermentação alcoólica foram de 33,44(PACTA); 41,56(BCA70); 68,95 (BCA90) e 71,38 (BCA120). Os resultados obtidos sugerem que as taxas de conversão dos resíduos celulósicos em glicose são fortemente dependentes da temperatura no processo de polpação alcalina. Os parâmetros cinéticos obtido nos ajustes cinéticos da hidrólise enzimática do BCA para a PACTA, PAC70, PAC90 e PAC120 foram: Vmax (g/h) igual a 7,20; 5,12; 4,54 e 0,87 respectivamente; Km (g) igual a 3,6; 2,56; 2,27 e 2,56 respectivamente; Kcat (h) igual a 1,44; 1,02; 0,91 e 0,17 respectivamente; Km/Vmax igual a 0,5 para todas as amostras e Kcat /Km igual a 0,4 para todas as amostras.
This work, it was proposed to evaluate mixtures of commercial enzymes by supplier Novozymes A / S. The enzymes used in this work were: celulase complex, xylanase, β-glucosidase, enzymático complex, xylanase and β-glucanase and glucoamylase in the glucose production from sugarcane bagasse subjected to treatment with alkali hydroxide solution sodium at room temperature, 70 ° C, 90 ° C and 120 ° C. The BCA yield on a dry basis after treatment with NaOH solution 6 (w / v) were 30.64% ± 1.395 (PACTA), 44.00% ± 1.787 (PAC70), 65.91% ± 1.096 (PAC90), and 95.25% ± 1.461 (CAP 120), respectively. The ash content for the BCA were 2.05% ± 0.027 (PACTA), 0.62% ± 0.013 (PAC70), 0.48% ± 0.007 (PAC90) and 0.18% ± 0.008 (PAC120). The lignin contents were 20.67 ± 0.603 (PACTA), 13.03 ± 0.711 (PAC70), 6.05 ± 0.196 (PAC90) and 5.49 ± 0.151 (PAC120). The results suggest that the conversion rates of cellulosic waste into glucose are strongly dependent on temperature in the alkaline pulping process. The kinetic parameters obtained in kinetic adjustments enzymatic hydrolysis of the BCA for PACTA, PAC70, PAC90 and PAC120 were: Vmax (g/h) equal to 7.20; 5.12; 4.54 and 0.87 respectively; Km (g) equal to 3.6; 2.56; 2.27 and 2.56 respectively; Kcat (h) equal to 1.44; 1.02; 0.91 and 0.17 respectively; Km/Vmax equal to 0.5 for all samples and Kcat/Km of 0.4 for all samples.

碩士
大葉大學
生物產業科技學系
98
Sugar fatty acid esters are new non-ionic surfactants consisting of a sugar and a fatty acid. Due to their amphiphilic nature, biodegradable, non-toxic and renewable function, they are of great interest in the food, cosmetic and pharmaceutical applications. Currently, esterification reactions are carried out by chemical processes in industries. The biosynthesis of such esters by lipase-catalyzed chemical reactions under mild conditions has become of much current commercial interest. According to currently available reference, most of them used lipase to catalyze the synthesis of sugar fatty acid esters from sucrose, fructose and maltose. Production of trehalose fatty acid with the lipase is quite limited in the literature. The aim of the stady was to establish a process for synthesis of trehalose fatty acid. The synthesis of trehalose fatty acid from trehalose and lipoic, was carried out by a esterification reaction catalyzed by immobilized lipase from Candida Antarctica (Novozym 435). The results showed that we had successfully obtained pure trehalose mono-lipoate which had been confirmed by HPLC-MASS. The actual chemical structure will be identified in the near future.

碩士
東海大學
化學工程與材料工程學系
99
Due to the depletion of petroleum deposits and the impacts of greenhouse effects, human beings are forced to look for some alternative energy in order to substitute for petroleum. Biofuel has attracted considerable interests for extensive researches and large-scale application by its specificities including biodegradation, non-toxicity, inexhaustible source and not increase carbon dioxide quantity in the atmosphere. Besides, there is a trend to replace petroleum by biofuel and a present tendency to apply carbohydrate instead of hydrocarbon. In this study, we produce biodiesel by exploiting enzymatic two-step method. In the first step, Candida rugosa Lipase hydrolyses soybean oil to get fatty acid; in the second step, Novozym 435 esterifies fatty acid to biodiesel. The better reaction condition for hydrolysis step is established, such as using 0.25% weight ratio of lipase to soybean oil in 0.1M sodium phosphate buffer (pH 7.0) under 35 ℃ for 12 hours, and then we can get the fatty acid yield 93.4 %. The preferable esterification condition is 2.0 % of weight ratio to methanol and fatty acid, the methanol / fatty acid molar ratio 15 under 30 ℃ for 16 hours, and then we can receive the esterification ratio 97.8 %. In addition, there are some advantages including moderate reaction, recyclable enzyme, shortened enzymatic reaction time and friendly reaction process when comparing the enzymatic two-step method with other three methods. However, the higher acid value for final product is the major consideration for the current procedure and needed to be overcome before industrial utilization.