O aproveitamento biotecnológico do glicerol representa uma alternativa para a redução dos problemas ambientais derivados do acúmulo de glicerol originado do processo de produção de biodiesel. O glicerol bruto (70,6% p/p) resultante do processo de transesterificação do óleo de soja e metanol foi submetido a tratamento com ácidos inorgânicos, com o objetivo de remover impurezas e reduzir a alcalinidade resultante do excesso de catalisador (KOH). A fração glicerínica resultante foi caracterizada quanto à concentração de glicerol, ésteres e íons metálicos; e empregada como fonte de carbono e energia para crescimento de bactérias probióticas. Os probióticos são organismos vivos que, quando administrados em quantidades adequadas, conferem benefício à saúde do hospedeiro. Quinze estirpes de Lactobacillus, com características probióticas, foram avaliadas quanto à capacidade de crescimento em meio contendo glicerol de biodiesel tratado (20 g/L) como principal fonte de carbono, sob condições de pHinicial=6,0 e 37 °C. Os resultados demonstraram a eficácia do ácido fosfórico para remoção de impurezas do glicerol bruto, o que permitiu a obtenção de uma fração contendo 900 a 964 g/L de glicerol. A avaliação de formulações de meios de cultivo contendo glicerol tratado revelou que treze estirpes de Lactobacillus mostraram capacidade de crescimento em glicerol de biodiesel, sendo os maiores rendimentos (YX/S) de 0,34, 0,28 e 0,26 g/g para as estirpes L. delbrueckii UFV-H2b20, L. acidophilus ATCC 4356 e L. plantarum ATCC 8014, respectivamente. A cinética de crescimento das estirpes selecionadas foi estudada em meio MRS modificado (ausência de glicose) contendo glicerol (10 g/L) suplementado ou não com citrato de amônio (2 g/L) e acetato de sódio (5,0 g/L), pH 6,0; 37 °C e 150 rpm. Os maiores rendimentos foram alcançados quando se utilizou meio MRS modificado contendo citrato de amônio e acetado de sódio; gerando valores de rendimentos correspondentes a 0,46, 0,38 e 0,46 g/g para L. delbrueckii UFV-H2b20, L. acidophilus ATCC 4356 e L. plantarum ATCC 8014, respectivamente. No tocante a atividade das enzimas envolvidas na assimilação de glicerol, glicerol quinase (EC. 2.7.1.30) e glicerol desidrogenase (EC.1.1.1.72), os resultados mostraram que, nos extratos livres de células de L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 e L. acidophilus ATCC 4356, os valores de atividade específica de glicerol quinase após 24 h de cultivo foram 91,1; 232,5 e 228,7 U/mg, respectivamente. Os valores da constante de Michaelis-Menten (Km) foram de 3,7; 1,2 e 2,5 mM para glicerol quinase e 19,2; 12,8; 33,3 e mM para glicerol desidrogenase de L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 e L. acidophilus ATCC 4356, respectivamente. Os valores de velocidades máximas (Vmáx) da reação foram de 46,4; 115,1 e 119,4 µM/min para glicerol quinase e 1,23; 1,03 e 2,7µM/min para glicerol desidrogenase de L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 e L. acidophilus ATCC 4356, respectivamente. A avaliação da técnica de encapsulamento de células de Lactobacillus probióticos em alginato-amido de banana verde (2%/2%) pela técnica de emulsificação em óleo vegetal e gelificação ionotrópica, permitiu a sobrevivência das células encapsuladas superior a 65%, na presença de fluído gástrico simulado, bem como sob condições de armazenagem a 4 °C. Os resultados do presente trabalho revelaram a potencialidade da utilização de glicerol de biodiesel como fonte de carbono e energia para o crescimento de bactérias lácticas que apresentam propriedades probióticas, visando a obtenção de um produto microencapsulado em matriz polimérica natural. / Biotechnological utilization of biodiesel-derived glycerol represents an alternative for the reduction of the environment concerns associated with the accumulation of this byproduct. Crude glycerol (70.6% w/w), obtained from the transesterification process of soybean oil and methanol; was treated with inorganic acids in order to remove impurities and decrease the alkalinity derived from the excess of catalyst (KOH). The glycerine fraction obtained was characterized regarding the final glycerol concentration, esters and metallic ions; and it was utilized as source of carbon and energy for growth of probiotic bacteria. Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Fifteen probiotic bacterial strains were screened to evaluated their capabilities to assimilate treated-glycerol (20 g/L) as main carbon source, at pH=6.0 and 37 °C. The results showed the effectiveness of the phosphoric acid for the removal of impurities from crude glycerol; allowing to attain a glycerol fraction containing 964 g/L. The evaluation of media containing treated glycerol revealed that thirteen strains of Lactobacillus showed capability to grow in biodiesel-derived glycerol, with yieds (YX/S) of glycerol conversion of 0.34, 0.28 and 0.26 g/g for L. delbrueckii UFV-H2b20, L. acidophilus ATCC 4356 and L. plantarum ATCC 8014, respectively. Kinetics of growth of the selected strains was studied in modified MRS medium containing glycerol(10 g/L) supplemented with or in the absence of ammonium citrate (2 g/L) and sodium acetate (5 g/L), pH 6.0; 37 °C and 150 rpm. The highest yields were attained in modified MRS containing ammonium citrate and sodium acetate; with 0.46, 0.38 and 0.46 g/g for L. delbrueckii UFV-H2b20, L. acidophilus ATCC 4356 and L. plantarum ATCC 8014, respectively. The free-cell extract of L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 and L. acidophilus ATCC 4356 showed activity for glycerol kinase (EC.2.7.1.30) and glycerol dehydrogenase (EC1.1.1.72). The maximal glycerol kinase activity was attained at the late exponential phase of growth, with 91.1; 232.5 and 228.7 U/mg for L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 and L. acidophilus ATCC 4356, respectively. The Michaelis-Menten (Km) values were 3.7; 1.2 and 2.5 mM for glycerol kinase and 19.2; 12.4 and 33.2 mM for glycerol dehydrogenase of L. plantarum ATCC 8014; L. delbrueckii UFV-H2b20 and L. acidophilus ATCC 4356, respectively. The maximum reaction rates (Vmáx) were 46.5; 115.1 and 119.4 µM/min for glycerol kinase and 1.23; 1.03 and 270 µM/min for glycerol dehydrogenase of L. plantarum ATCC 8014; L. delbrueckii UFV-H2b20 and L. acidophilus ATCC 4356, respectively. Furthermore, the results of the evaluation of probiotic Lactobacillus cell encapsulation in alginate-unripe banana starch (2%/2%) obtained by emusification in soybean oil and ionotropic gelification with calcium chloride, showed a cell survival rate higher than 65%, regarding the initial cell concentration in simulated gastric fluid,and during 28 days stored at 4 °C. The results revealed that, glycerol from biodiesel production process represents a potential carbon and energy source for the growth of probiotic bacteria.

O presente trabalho de pesquisa teve como objetivo principal avaliar o efeito da carga orgânica volumétrica aplicada (COVA) na produção de hidrogênio usando o reator AnSBBR com recirculação operado em batelada e biomassa imobilizada. Para este efeito, o reator foi operado a 30ºC com dois tempos de ciclo (3 e 4 h), alimentado com três concentrações afluentes (3000, 4000 e 5000 mgDQO.L-1), uma velocidade de recirculação de 30 L.h-1, usando glicerol como única fonte de carbono e a biomassa de uma estação de tratamento de abatedouro de aves. A combinação destes fatores fez com que o reator fosse operado com seis cargas orgânicas volumétricas aplicadas diferentes (7565, 9764, 12911, 10319, 13327 e 16216 mgDQO.L-1.d-1). Os resultados mostraram que não existiu uma tendência clara entre a carga orgânica aplicada e a produção de hidrogênio. Porém, os melhores resultados quanto à produção de hidrogênio foram atingidos quando o reator foi operado com 4 horas de tempo de ciclo e alimentado com uma concentração afluente de 5000 mgDQO.L-1 (COVA de 12911 mgDQO.L-1.d-1), sendo sua produtividade molar média de hidrogênio (PrM) de 67,5 molH2.m-3.d-1. Esta condição também atingiu o melhor rendimento molar de hidrogênio por carga orgânica aplicada RMCAS,m e o melhor rendimento molar de hidrogênio por carga orgânica removida (RMCRS,m), sendo estes de 5,2 e 21,1 molH2.kgDQO-1, respectivamente. Adicionalmente foi estudada a diferença na produção de hidrogênio entre o uso de biomassa pré-tratada e não tratada termicamente, cuja análise de variância (ANOVA) mostrou que a diferença não foi estatisticamente significativa. Finalmente o reator foi operado usando glicerina bruta industrial para comparar os resultados com aqueles obtidos operando com glicerol, observando-se uma clara desvantagem na produção de hidrogênio quando foi usada glicerina bruta. Em geral, o reator AnSBBR operado em batelada sequencial apresentou resultados promissores na produção de hidrogênio usando glicerol como fonte de carbono, porém estudos mais profundos ainda são necessários no intuito de otimizar o sistema para a utilização de glicerina bruta. / This study evaluated the influence of applied volumetric organic load on biohydrogen production in an anaerobic sequencing batch biofilm reactor (AnSBBR) with 3.5 L of liquid medium and treating 1.5 L of glycerin based wastewater per cycle at 30ºC. The reactor was operated with two cycle periods (3 and 4 hours), three influent concentrations (3000, 4000 and 5000 mgCOD.L-1), recirculation rate of 30 L.h-1 and an inoculum from a poultry slaughterhouse. Six applied volumetric organic loads (AVOLCT) were generated from the combination of cycle period and influent concentrations (7565, 9764, 12911, 10319, 13327 e 16216 mgCOD.L-1.d-1). There was not a clear relation between the applied volumetric organic load and hydrogen production. However, the highest hydrogen molar production (MPr: 67.5 molH2.m-3 .d-1) was reached when the reactor was operated with a cycle period of 4 h and an influent concentration of 5000 mgCOD.L-1 (AVOLCT: 12911 mgCOD.L-1. d-1). This condition also reached the highest molar yield per removed load based on organic matter (MYRLC,m: 5.2 molH2.kgCOD-1) and the highest molar yield per applied load based on organic matter (MYALC,m: 21.1 molH2.kgCOD-1). In addition, it was studied whether existed or not a statistical significant difference on molar productivity averages pre-treating and not pre-treating the inoculum. It was observed that this was not statistically significant (p>0.05). Finally, the reactor was operated using crude glycerol as a sole source of carbon to evaluate hydrogen production. The disadvantage on hydrogen production when crude glycerol was used comparing to pure glycerol was clearly observed. The AnSBBR used on hydrogen production experiments operated with pure glycerol as a sole carbon XIV source showed an important potential. Nevertheless, additional studies are required in order to optimize results.

O presente trabalho de pesquisa teve como objetivo principal avaliar o efeito da carga orgânica volumétrica aplicada (COVA) na produção de hidrogênio usando o reator AnSBBR com recirculação operado em batelada e biomassa imobilizada. Para este efeito, o reator foi operado a 30ºC com dois tempos de ciclo (3 e 4 h), alimentado com três concentrações afluentes (3000, 4000 e 5000 mgDQO.L-1), uma velocidade de recirculação de 30 L.h-1, usando glicerol como única fonte de carbono e a biomassa de uma estação de tratamento de abatedouro de aves. A combinação destes fatores fez com que o reator fosse operado com seis cargas orgânicas volumétricas aplicadas diferentes (7565, 9764, 12911, 10319, 13327 e 16216 mgDQO.L-1.d-1). Os resultados mostraram que não existiu uma tendência clara entre a carga orgânica aplicada e a produção de hidrogênio. Porém, os melhores resultados quanto à produção de hidrogênio foram atingidos quando o reator foi operado com 4 horas de tempo de ciclo e alimentado com uma concentração afluente de 5000 mgDQO.L-1 (COVA de 12911 mgDQO.L-1.d-1), sendo sua produtividade molar média de hidrogênio (PrM) de 67,5 molH2.m-3.d-1. Esta condição também atingiu o melhor rendimento molar de hidrogênio por carga orgânica aplicada RMCAS,m e o melhor rendimento molar de hidrogênio por carga orgânica removida (RMCRS,m), sendo estes de 5,2 e 21,1 molH2.kgDQO-1, respectivamente. Adicionalmente foi estudada a diferença na produção de hidrogênio entre o uso de biomassa pré-tratada e não tratada termicamente, cuja análise de variância (ANOVA) mostrou que a diferença não foi estatisticamente significativa. Finalmente o reator foi operado usando glicerina bruta industrial para comparar os resultados com aqueles obtidos operando com glicerol, observando-se uma clara desvantagem na produção de hidrogênio quando foi usada glicerina bruta. Em geral, o reator AnSBBR operado em batelada sequencial apresentou resultados promissores na produção de hidrogênio usando glicerol como fonte de carbono, porém estudos mais profundos ainda são necessários no intuito de otimizar o sistema para a utilização de glicerina bruta. / This study evaluated the influence of applied volumetric organic load on biohydrogen production in an anaerobic sequencing batch biofilm reactor (AnSBBR) with 3.5 L of liquid medium and treating 1.5 L of glycerin based wastewater per cycle at 30ºC. The reactor was operated with two cycle periods (3 and 4 hours), three influent concentrations (3000, 4000 and 5000 mgCOD.L-1), recirculation rate of 30 L.h-1 and an inoculum from a poultry slaughterhouse. Six applied volumetric organic loads (AVOLCT) were generated from the combination of cycle period and influent concentrations (7565, 9764, 12911, 10319, 13327 e 16216 mgCOD.L-1.d-1). There was not a clear relation between the applied volumetric organic load and hydrogen production. However, the highest hydrogen molar production (MPr: 67.5 molH2.m-3 .d-1) was reached when the reactor was operated with a cycle period of 4 h and an influent concentration of 5000 mgCOD.L-1 (AVOLCT: 12911 mgCOD.L-1. d-1). This condition also reached the highest molar yield per removed load based on organic matter (MYRLC,m: 5.2 molH2.kgCOD-1) and the highest molar yield per applied load based on organic matter (MYALC,m: 21.1 molH2.kgCOD-1). In addition, it was studied whether existed or not a statistical significant difference on molar productivity averages pre-treating and not pre-treating the inoculum. It was observed that this was not statistically significant (p>0.05). Finally, the reactor was operated using crude glycerol as a sole source of carbon to evaluate hydrogen production. The disadvantage on hydrogen production when crude glycerol was used comparing to pure glycerol was clearly observed. The AnSBBR used on hydrogen production experiments operated with pure glycerol as a sole carbon XIV source showed an important potential. Nevertheless, additional studies are required in order to optimize results.

O aproveitamento biotecnológico do glicerol representa uma alternativa para a redução dos problemas ambientais derivados do acúmulo de glicerol originado do processo de produção de biodiesel. O glicerol bruto (70,6% p/p) resultante do processo de transesterificação do óleo de soja e metanol foi submetido a tratamento com ácidos inorgânicos, com o objetivo de remover impurezas e reduzir a alcalinidade resultante do excesso de catalisador (KOH). A fração glicerínica resultante foi caracterizada quanto à concentração de glicerol, ésteres e íons metálicos; e empregada como fonte de carbono e energia para crescimento de bactérias probióticas. Os probióticos são organismos vivos que, quando administrados em quantidades adequadas, conferem benefício à saúde do hospedeiro. Quinze estirpes de Lactobacillus, com características probióticas, foram avaliadas quanto à capacidade de crescimento em meio contendo glicerol de biodiesel tratado (20 g/L) como principal fonte de carbono, sob condições de pHinicial=6,0 e 37 °C. Os resultados demonstraram a eficácia do ácido fosfórico para remoção de impurezas do glicerol bruto, o que permitiu a obtenção de uma fração contendo 900 a 964 g/L de glicerol. A avaliação de formulações de meios de cultivo contendo glicerol tratado revelou que treze estirpes de Lactobacillus mostraram capacidade de crescimento em glicerol de biodiesel, sendo os maiores rendimentos (YX/S) de 0,34, 0,28 e 0,26 g/g para as estirpes L. delbrueckii UFV-H2b20, L. acidophilus ATCC 4356 e L. plantarum ATCC 8014, respectivamente. A cinética de crescimento das estirpes selecionadas foi estudada em meio MRS modificado (ausência de glicose) contendo glicerol (10 g/L) suplementado ou não com citrato de amônio (2 g/L) e acetato de sódio (5,0 g/L), pH 6,0; 37 °C e 150 rpm. Os maiores rendimentos foram alcançados quando se utilizou meio MRS modificado contendo citrato de amônio e acetado de sódio; gerando valores de rendimentos correspondentes a 0,46, 0,38 e 0,46 g/g para L. delbrueckii UFV-H2b20, L. acidophilus ATCC 4356 e L. plantarum ATCC 8014, respectivamente. No tocante a atividade das enzimas envolvidas na assimilação de glicerol, glicerol quinase (EC. 2.7.1.30) e glicerol desidrogenase (EC.1.1.1.72), os resultados mostraram que, nos extratos livres de células de L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 e L. acidophilus ATCC 4356, os valores de atividade específica de glicerol quinase após 24 h de cultivo foram 91,1; 232,5 e 228,7 U/mg, respectivamente. Os valores da constante de Michaelis-Menten (Km) foram de 3,7; 1,2 e 2,5 mM para glicerol quinase e 19,2; 12,8; 33,3 e mM para glicerol desidrogenase de L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 e L. acidophilus ATCC 4356, respectivamente. Os valores de velocidades máximas (Vmáx) da reação foram de 46,4; 115,1 e 119,4 µM/min para glicerol quinase e 1,23; 1,03 e 2,7µM/min para glicerol desidrogenase de L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 e L. acidophilus ATCC 4356, respectivamente. A avaliação da técnica de encapsulamento de células de Lactobacillus probióticos em alginato-amido de banana verde (2%/2%) pela técnica de emulsificação em óleo vegetal e gelificação ionotrópica, permitiu a sobrevivência das células encapsuladas superior a 65%, na presença de fluído gástrico simulado, bem como sob condições de armazenagem a 4 °C. Os resultados do presente trabalho revelaram a potencialidade da utilização de glicerol de biodiesel como fonte de carbono e energia para o crescimento de bactérias lácticas que apresentam propriedades probióticas, visando a obtenção de um produto microencapsulado em matriz polimérica natural. / Biotechnological utilization of biodiesel-derived glycerol represents an alternative for the reduction of the environment concerns associated with the accumulation of this byproduct. Crude glycerol (70.6% w/w), obtained from the transesterification process of soybean oil and methanol; was treated with inorganic acids in order to remove impurities and decrease the alkalinity derived from the excess of catalyst (KOH). The glycerine fraction obtained was characterized regarding the final glycerol concentration, esters and metallic ions; and it was utilized as source of carbon and energy for growth of probiotic bacteria. Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Fifteen probiotic bacterial strains were screened to evaluated their capabilities to assimilate treated-glycerol (20 g/L) as main carbon source, at pH=6.0 and 37 °C. The results showed the effectiveness of the phosphoric acid for the removal of impurities from crude glycerol; allowing to attain a glycerol fraction containing 964 g/L. The evaluation of media containing treated glycerol revealed that thirteen strains of Lactobacillus showed capability to grow in biodiesel-derived glycerol, with yieds (YX/S) of glycerol conversion of 0.34, 0.28 and 0.26 g/g for L. delbrueckii UFV-H2b20, L. acidophilus ATCC 4356 and L. plantarum ATCC 8014, respectively. Kinetics of growth of the selected strains was studied in modified MRS medium containing glycerol(10 g/L) supplemented with or in the absence of ammonium citrate (2 g/L) and sodium acetate (5 g/L), pH 6.0; 37 °C and 150 rpm. The highest yields were attained in modified MRS containing ammonium citrate and sodium acetate; with 0.46, 0.38 and 0.46 g/g for L. delbrueckii UFV-H2b20, L. acidophilus ATCC 4356 and L. plantarum ATCC 8014, respectively. The free-cell extract of L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 and L. acidophilus ATCC 4356 showed activity for glycerol kinase (EC.2.7.1.30) and glycerol dehydrogenase (EC1.1.1.72). The maximal glycerol kinase activity was attained at the late exponential phase of growth, with 91.1; 232.5 and 228.7 U/mg for L. plantarum ATCC 8014, L. delbrueckii UFV-H2b20 and L. acidophilus ATCC 4356, respectively. The Michaelis-Menten (Km) values were 3.7; 1.2 and 2.5 mM for glycerol kinase and 19.2; 12.4 and 33.2 mM for glycerol dehydrogenase of L. plantarum ATCC 8014; L. delbrueckii UFV-H2b20 and L. acidophilus ATCC 4356, respectively. The maximum reaction rates (Vmáx) were 46.5; 115.1 and 119.4 µM/min for glycerol kinase and 1.23; 1.03 and 270 µM/min for glycerol dehydrogenase of L. plantarum ATCC 8014; L. delbrueckii UFV-H2b20 and L. acidophilus ATCC 4356, respectively. Furthermore, the results of the evaluation of probiotic Lactobacillus cell encapsulation in alginate-unripe banana starch (2%/2%) obtained by emusification in soybean oil and ionotropic gelification with calcium chloride, showed a cell survival rate higher than 65%, regarding the initial cell concentration in simulated gastric fluid,and during 28 days stored at 4 °C. The results revealed that, glycerol from biodiesel production process represents a potential carbon and energy source for the growth of probiotic bacteria.

Cette thèse porte sur la conception de carbonates cycliques originaux et d’amines dérivés des huiles végétales dans le but de synthétiser des poly(hydroxyuréthane)s entièrement bio-sourcés. D’une part, deux voies d’accès à des amines dérivées d’acides gras utilisant des conditions douces ont été étudiées. La première consiste en l’oxydation sous air d’alcools aliphatiques en nitriles en présence de TEMPO supporté sur silice, suivi par une hydrogénation des dinitriles en diamines. Egalement, des diènes dérivés d’acides gras ont été couplés à la cystéamine via une chimie thiol-ène, permettant l’accès à des diamines aliphatiques bio-sourcées. D’autre part, des carbonates cycliques substitués à 5 chaînons ont été synthétisés à partir de dérivés d’acides gras et de glycérol, dans le but d’augmenter leur réactivité vis-à-vis de l’aminolyse. En insérant un groupement fonctionnel éther, thio-éther ou ester en position α ou β des carbonates cycliques, la réactivité de ces derniers vis-à-vis des amines a pu être ajustée. L’étude de la sélectivité, des réactions secondaires et de la catalyse de la voie carbonate/amine a été menée afin de mieux appréhender cette voie d’accès à des polyuréthanes sans isocyanates. Des poly(hydroxyuréthane)s entièrement oléo-sourcés ont été synthétisés avec succès, montrant des propriétés physico-chimiques contrôlables selon la structure des monomères. / In this thesis, vegetable oils were used as a platform to design original cyclic carbonates and amines with the goal to synthesize fully bio-based poly(hydroxyurethane)s. On the one hand, two routes to fatty acid-based amines were implemented in mild conditions. First, the oxidation of aliphatic alcohols into nitriles was performed under air in the presence of supported TEMPO on silica, followed by hydrogenation of nitrile compounds into corresponding amines. Second, thiol-ene chemistry was performed on unsaturated fatty acid substrates to design original aliphatic bio-based diamines. On the other hand, substituted 5-membered cyclic carbonates were designed from fatty acids and glycerol derivatives to enhance their reactivity towards aminolysis. By inserting ether, thio-ether or ester functionalities in α- or β-position of the cyclic carbonates, their reactivity towards amines could be tuned. Investigations on the selectivity, side reactions and catalysis of the carbonate-amine reaction were carried out to apprehend this route to non-isocyanate polyurethanes. Fully vegetable oil-based PHUs with tunable physico-chemical properties with respect to the monomer structures could be easily achieved.

Soybean (Glycine max (L.) Merr) is the largest oil and protein crop in the world and it is grown for both oil and protein. To address the needs of both the edible oil market and industrial applications of soybean oil, fatty acid modification has been a focus of soybean breeding programs. Natural variation, mutagenesis and genetic engineering have been used to alter the fatty acid profile. Several genes, mostly desaturases, have been associated with altered fatty acid profiles but enzymes in the Kennedy Pathway have yet to be studied as another source of genetic variation for altering the fatty acid profiles. The Kennedy Pathway is also known as the oil producing pathway and consists of four enzymes: glycerol-3-phosphate acyltransferase (G3PAT); lysophosphatidic acid acyltransferase (LPAAT); phosphatidic acid phosphatase (PAP); and diacylglycerol acyltransferase 1 (DGAT1). The starting material for this pathway is glycerol-3-phosphate, which is produced from glycerol by glycerol kinase (GK), and the product of this pathway is triacylglycerol (TAG). The overall objective of this study was to elucidate the role that the Kennedy Pathway plays in determining the fatty acid profile in two ways: (1) sequencing the transcribed region of the genomic genes encoding the enzymes of GK, G3PAT, LPAAT, and DGAT1 in soybean genotypes with altered fatty acid profiles; and (2) studying their expression over seed development, across three growing temperatures. The genetic material for the study consisted of four soybean genotypes with altered fatty acid profile: RG2, RG7, RG10, and SV64-53. Results from sequencing showed that the mutations identified in G3PAT, LPAAT, and DGAT1 in the four soybean genotypes did not explain the differences in the fatty acid profiles. The expression of G3PAT, LPAAT, and DGAT1 over seed development showed that G3PAT had the lowest levels, followed by LPAAT, then DGAT1, across the growing temperatures. The differences in expression among genotypes corresponded to differences in fatty acid accumulation, suggesting that expression rather than genetic mutations in the transcribed region of the genes influenced the fatty acid profile of the genotypes in this study. In conclusion, the enzymes of the Kennedy Pathway appear to contribute to the altered fatty acid profiles observed in the soybean mutant genotypes. / Ontario Ministry of Economic Development and Innovation (formerly Ontario Ministry of Research and Innovation), BioCar Initiative, Grain Farmers of Ontario, SeCan

Environmental problems generated due the widespread use of fossil fuels has led the search for new energy alternatives. In this context, the biodiesel emerged as a product of great interest. However, the increase in the biofuel production leads to the production of large amounts of glycerol, which emerges as a cheap raw material with high functionality to produce different products such acrolein (currently it is obtained by selective propylene oxidation), 1,2-propanediol and others. In this study, previously, was performed a theorical and thermodynamic study of acrolein production from glycerol and others products. Catalytic tests from glycerol under different acid solid catalysts, such as materials based on alumina, niobium and zeolite, temperatures between 275 and 350°C and atmospheric pressure were performed. The catalysts were characterized by nitrogen physisorption, X-ray diffraction (XRD), temperature programmed desorption (TPD) and temperature programmed oxidation (TPO). The aim of this study is to evaluate the performance of catalysts and reaction temperature influence, in the formation of products as acrolein and acetol, main products of the reaction of dehydration of glycerol. / Problemas ambientais gerados devido ao uso generalizado de combustíveis fósseis têm levado a busca por novas alternativas energéticas. Nesse contexto, o biodiesel, surge como um combustível de grande interesse. Entretanto, o aumento na produção deste biocombustível acarreta a produção de grandes quantidades de glicerol, que por sua vez, desponta como uma matéria-prima com baixo valor de mercado e de grande funcionalidade para produção de diferentes produtos, tais como a acroleína (atualmente obtido pela oxidação seletiva do propeno), 1,2-propanodiol, entre outros. Neste trabalho, previamente foi realizado um estudo teórico e termodinâmico da reação de formação da acroleína e outras possíveis reações que podem ocorrer no sistema reacional. Testes catalíticos a partir do glicerol sob diferentes catalisadores sólidos ácidos, tais como materiais a base de alumina, nióbio e zeólita, temperaturas entre 275 e 350°C e pressão ambiente foram realizados. Os catalisadores foram caracterizados por fisissorção de nitrogênio, difratometria de raio-x (DRX), dessorção à temperatura programada (TPD) e oxidação à temperatura programada (TPO). O objetivo deste trabalho é a avaliação do desempenho de catalisadores e da influência da temperatura reacional na formação de produtos como a acroléina e acetol, principais produtos da reação de desidratação do glicerol. / Mestre em Engenharia Química

Increasing environmental awareness has driven a lot of research to look into various environmentally friendly lubricants which can replace more conventional mineral oil based lubricants. This is true in particular for marine and hydropower applications where the risk of lubricant leakage can be damaging to the local environment. Glycerol is an organic compound produced as a byproduct when producing Biodiesel. It is environmentally friendly and has been used by the pharmaceutical and food industries for a long time. Recent research has shown that glycerol has very good tribological properties and can be used as a lubricant in some applications. However, its high viscosity and high static friction are disadvantageous and needs improvement. The purpose of this study is to investigate possible surface active environmentally adapted additives in glycerol and water solutions. 14 additives have been selected for testing and were tested in a pin-on-disc start-stop friction test to see their effect on the static and dynamic friction coefficients. From these 14 additives two were selected due to their superior performance and were further studied. The effect of concentration of water and additive in glycerol was also investigated using the same test conditions. A phosphor based additive has been found to be the best performing.

La Province Volcanique du Rungwe (PVR) en Afrique de l’Est abrite diverses archives continentales (séquence de loess-paléosols, tourbières, lacs) permettant d’étudier les changements environnementaux passés des zones tropicales continentales. Ce travail s’est intéressé à l’applicabilité des alkyl tetraéthers de glycérol (tetraéthers) et des n-alcanes comme biomarqueurs de ces changements passés. Leur analyse le long de transects altitudinaux a permis de rendre compte de la capacité des tetraéthers à enregistrer de faibles changements de température de l’air dans la région. En conséquence, une calibration régionale a été établie afin d’améliorer les reconstructions de température de l’air en Afrique de l’Est. Au contraire, il est apparu que la composition isotopique de l’hydrogène des n-alcanes (δ²Hwax) était impactée par des paramètres physiques et biologiques supplémentaires ce qui complique son utilisation pour suivre les changements de température à l’échelle régionale. L’étude des variations de ces deux biomarqueurs le long d’une carotte de tourbe et d’une carotte de sédiment lacustre prélevées dans la PVR a révélé l’existence synchrone d’une période climatique plus chaude au cours de l’Holocène tardif. Par ailleurs, il a été observé dans la carotte de tourbe une transition d’un lac à une tourbière il y a ca. 2000 ans BP. Le présent travail démontre donc que les tetraéthers et les n-alcanes sont des biomarqueurs prometteurs, notamment parce qu’ils sont sensibles à de faibles variation climatiques ; cependant, afin de les interpréter correctement, il est nécessaire d’adopter une approche multi-marqueurs. / The Rungwe Volcanic Province (RVP) in East Africa offers a wide diversity of continental archives (loess-paleosols sequences, peatlands, lakes), allowing the investigation of past environmental changes in tropical continents. This work focused on the validation of glycerol dialkyl glycerol tetraether- (GDGT) and n-alkane-derived proxies. Analyses of these two biomarkers along altitudinal transects allowed assessing their ability to record temperature changes in the region. GDGTs were found to be robust temperature proxies in East Africa, and a regional calibration was established to improve temperature reconstructions from soil archives. In contrast, investigation of n-alkane hydrogen isotopic composition (δ²Hwax) in surface soils revealed that its variations seemed to be impacted by additional biological and physical parameters than temperature, preventing its generalization at a regional scale. Application of GDGT and n-alkane proxies to continental archives revealed past environmental changes over the Late Holocene in the RVP. A late Holocene synchronous temperature maximum was especially observed in a peat core and sediment core from two sites of the RVP. A multi-proxy approach was applied to the peat core, revealing that an ecosystem change from a lake to a peatland occurred ca. 2000 yrs BP ago. The present work showed that GDGTs and n-alkanes are promising biomarkers because of their sensitivity to slight climate variations, but that they need to be combined with other proxies to accurately reconstruct environmental changes.

Peripheral nerves have demonstrated the ability to bridge gaps of up to 6 mm. Peripheral Nerve System injury sites beyond this range need autograft or allograft surgery. Central Nerve System cells do not allow spontaneous regeneration due to the intrinsic environmental inhibition. Although stem cell therapy seems to be a promising approach towards nerve repair, it is essential to use the distinct three-dimensional architecture of a cell scaffold with proper biomolecule embedding in order to ensure that the local environment can be controlled well enough for growth and survival. Many approaches have been developed for the fabrication of 3D scaffolds, and more recently, fiber-based scaffolds produced via the electrospinning have been garnering increasing interest, as it offers the opportunity for control over fiber composition, as well as fiber mesh porosity using a relatively simple experimental setup. All these attributes make electrospun fibers a new class of promising scaffolds for neural tissue engineering. Therefore, the purpose of this doctoral study is to investigate the use of the novel material PGD and its derivative PGDF for obtaining fiber scaffolds using the electrospinning. The performance of these scaffolds, combined with neural lineage cells derived from ESCs, was evaluated by the dissolvability test, Raman spectroscopy, cell viability assay, real time PCR, Immunocytochemistry, extracellular electrophysiology, etc. The newly designed collector makes it possible to easily obtain fibers with adequate length and integrity. The utilization of a solvent like ethanol and water for electrospinning of fibrous scaffolds provides a potentially less toxic and more biocompatible fabrication method. Cell viability testing demonstrated that the addition of gelatin leads to significant improvement of cell proliferation on the scaffolds. Both real time PCR and Immunocytochemistry analysis indicated that motor neuron differentiation was achieved through the high motor neuron gene expression using the metabolites approach. The addition of Fumaric acid into fiber scaffolds further promoted the differentiation. Based on the results, this newly fabricated electrospun fiber scaffold, combined with neural lineage cells, provides a potential alternate strategy for nerve injury repair.