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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Étude de prévalence et associations des gènes de virulence et résistance aux antimicrobiens d’Escherichia coli de la flore intestinale du poulet sain

Kaboré, Kiswendsida Paul 08 1900 (has links)
Les Escherichia coli pathogènes de la volaille (APEC) font partie des E. coli extra-intestinaux pathogènes (ExPEC) et seraient un réservoir possible de gènes de virulence et de résistance aux antimicrobiens (RAM) des ExPEC chez l’humain. L’objectif de cette étude était d’évaluer l’effet d’un prébiotique et d’un mélange d’acide organique et d’huiles essentielles encapsulés sur la prévalence des gènes de virulence des ExPEC et de RAM, ainsi que les associations entre ces gènes chez E. coli de l’intestin du poulet sain. Des échantillons de contenus caecaux de poulets de 29 jours d’âge ayant reçu un de ces ingrédients alimentaires comparativement à des témoins ont été analysés pour la présence des gènes de virulence iucD, tsh, papC et des gènes de RAM blaTEM, blaSHV, tetA, tetC, blaCMY-2, aadA1, aac3 par PCR. La prévalence d’iucD était supérieure dans le groupe témoin comparativement aux groupes «prébiotique» et «acide organique» et la prévalence de papC était affectée dans le groupe «acide organique». La prévalence d’isolats d’E.coli positifs pour blaCMY-2 était supérieure dans le groupe témoin comparée aux groupes «prébiotique» et «acide organique», tel que démontré par la technique d’hybridation de l’ADN sur HGMF (Hydrophobic Grid Membrane Filter). De plus, la prévalence des isolats d’E. coli positifs pour tetA, blaTEM, aadA1 ou tsh était affectée par les ingrédients alimentaires. Dans l’ensemble, des associations entre la présence de tsh et iucD, blaTEM et aadA1, et iucD et blaCMY-2 ont été observées. .Cette étude démontre l’utilité de certains ingrédients alimentaires pour dimunier le risque d’exposition en santé publique. / Avian Pathogenic E. coli (APEC) belong to the extra-intestinal pathogenic E. coli (ExPEC) pathotype, and may be a virulence and antimicrobial resistance (AMR) gene reservoir for ExPEC in humans. The aim of this study was to evaluate the effect of addition to the feed of a prebiotic or an organic acid on the prevalence of ExPEC-associated virulence genes and antimicrobial resistance (AMR) genes and the association between these genes in E. coli of the intestinal microflora of healthy chickens. Caecal contents from 29-day-old chickens having received one of these feed ingredients in comparison to a control group were examined for the presence of virulence genes iucD, tsh, and papC and AMR genes blaTEM, blaSHV, tetA, tetC, blaCMY-2, aadA1, and aac3 by PCR. The prevalence of iucD was significantly higher in the control group than in the prebiotic and organic acid groups and prevalence of papC was affected by the use of the organic acid. The prevalence of blaCMY-2-positive E. coli isolates was higher in the control group than the prebiotic or organic acid groups, as demonstrated by Hydrophobic–grid membrane filter (HGMF) DNA probe colony hybridization. In addition, the prevalence of E. coli isolates positive for tetA, blaTEM, aadA1 or tsh was affected by the use of these feed ingredients. Overall, associations between the presence of iucD and tsh, blaTEM and aadA1, and iucD and blaCMY-2 were observed. This study demonstrates that the use of certain feed ingredients could reduce the risk of exposure in a public health perspective.
92

Perfil de textura em conserva de carne bovina (Corned Beef) submetida a diferentes tratamentos térmicos e sua relação com a concentração das proteínas dos tecidos muscular e conjuntivo colagenoso

Montezuma, Ronaldo [UNESP] 12 March 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:24:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-03-12Bitstream added on 2014-06-13T18:52:40Z : No. of bitstreams: 1 montezuma_r_me_rcla.pdf: 2261471 bytes, checksum: e8de3c70b94bdde4b8cd09e24247eaf2 (MD5) / O objetivo desta pesquisa foi determinar o Perfil de Textura (TPA) em formulações comerciais de “carne bovina em conserva” (corned beef) enlatada processada termicamente e avaliar sua relação com os valores de esterilização (F0), com a Concentração da Proteína do Tecido Conjuntivo Colagenoso (CCTP) e com a Concentração da Proteína do Tecido Muscular (MTP). Foram selecionados 14 lotes de produção de corned beef em latas tronco trapezoidais de 340 g correspondentes ao padrão continental Campden A e destes foram retiradas 24 latas do produto dos sub lotes submetidos ao processamento térmico. Destas latas foram retiradas seis amostras aleatórias para determinação do TPA e para análise da composição visando determinação da Proteína do Tecido Conjuntivo Colagenoso (CCTP), da Proteína do Tecido Muscular (MTP) e do Conteúdo Carne Magra (LMC). As latas de corned beef analisadas foram submetidas a tratamentos térmicos de 75,0 a 76,7 minutos, com a temperatura da autoclave a 121o C e resfriamento a 35o C durante 60 minutos, obtendo-se valores de F0 no centro de massa do produto variando de 14,8 a 20 minutos. Os parâmetros de TPA dureza, fraturabilidade, coesividade, elasticidade, adesividade, mastigabilidade, gomosidade e resiliência foram determinados no bloco integral do produto bloco resfriado a 4ºC em oito pontos na superfície. Os mesmos blocos do produto utilizados para determinação do TPA foram analisados quanto à composição média, apresentando concentração de 0,4 a 2,5% para CCTP, de 21,7 a 25,3% para MTP e de 102,79 a 107,95% para LMC. Os tratamentos de corned beef avaliados apresentaram diferenças significativas pelo teste de Tukey nas médias dos parâmetros dureza, gomosidade, mastigabilidade, adesividade e elasticidade. Os três primeiros parâmetros apresentaram correlações significativas fortemente negativas com o valor... / The objectives of this research were the determination of the texture profile of canned corned beef thermally processed and to evaluate its relationship with the sterilization value (F0) and the composition. Fourteen production batches of Campden A grade 340-g corned beef cans were selected, from which twenty-four cans of the thermal process sub-batches were retrieved. From the sub-batches, six random sample cans were taken and its content submitted to the Texture Profile Analysis (TPA) and to the composition analysis to determine the concentration of the Collagenous Connective Tissue Protein (CCTP), the Muscular Tissue Protein (MTP) concentration and the Lean Meat Content (LMC). The corned beef samples analyzed were submitted to thermal treatments at 121o C (retort steam temperature) for varying heating times, from 75 to 76 minutes and cooled at 35o C (retort water temperature) during 35 minutes, to obtain F0 values at the product center point varying from 14.8 to 20 minutes. The TPA parameters were determined in 8 points of the whole corned beef loaf of each sample, previously chilled and stabilized at 4o C temperature, to obtain hardness, fracturability, cohesiveness, elasticity, adhesiveness, springiness, gumminess, chewiness and resilience. The same sample material were then analyzed in terms of average composition of the product, resulting in concentrations in the range of 0.4 to 2.5% for CCTP, 21.7 to 25.3% for MTP and content from 102.8% to 108.0% for LMC. The treated corned beef samples analyzed showed significant differences in the means for hardness, adhesiveness, chewiness and elasticity. These parameters showed dependence with the sterilization value (F0), revealing negative strong significant correlation for F0 with hardness, gumminess and chewiness. The MTP and LMC values showed a high positive significant correlation with cohesiveness. It was observed a high... (Complete abstract click electronic access below)
93

Perfil de textura em conserva de carne bovina (Corned Beef) submetida a diferentes tratamentos térmicos e sua relação com a concentração das proteínas dos tecidos muscular e conjuntivo colagenoso /

Montezuma, Ronaldo. January 2010 (has links)
Orientador: Roger Darros Barbosa / Banca: Pedro Fernando Romanelli / Banca: Marcos Franke Pinto / Resumo: O objetivo desta pesquisa foi determinar o Perfil de Textura (TPA) em formulações comerciais de "carne bovina em conserva" (corned beef) enlatada processada termicamente e avaliar sua relação com os valores de esterilização (F0), com a Concentração da Proteína do Tecido Conjuntivo Colagenoso (CCTP) e com a Concentração da Proteína do Tecido Muscular (MTP). Foram selecionados 14 lotes de produção de corned beef em latas tronco trapezoidais de 340 g correspondentes ao padrão continental Campden A e destes foram retiradas 24 latas do produto dos sub lotes submetidos ao processamento térmico. Destas latas foram retiradas seis amostras aleatórias para determinação do TPA e para análise da composição visando determinação da Proteína do Tecido Conjuntivo Colagenoso (CCTP), da Proteína do Tecido Muscular (MTP) e do Conteúdo Carne Magra (LMC). As latas de corned beef analisadas foram submetidas a tratamentos térmicos de 75,0 a 76,7 minutos, com a temperatura da autoclave a 121o C e resfriamento a 35o C durante 60 minutos, obtendo-se valores de F0 no centro de massa do produto variando de 14,8 a 20 minutos. Os parâmetros de TPA dureza, fraturabilidade, coesividade, elasticidade, adesividade, mastigabilidade, gomosidade e resiliência foram determinados no bloco integral do produto bloco resfriado a 4ºC em oito pontos na superfície. Os mesmos blocos do produto utilizados para determinação do TPA foram analisados quanto à composição média, apresentando concentração de 0,4 a 2,5% para CCTP, de 21,7 a 25,3% para MTP e de 102,79 a 107,95% para LMC. Os tratamentos de corned beef avaliados apresentaram diferenças significativas pelo teste de Tukey nas médias dos parâmetros dureza, gomosidade, mastigabilidade, adesividade e elasticidade. Os três primeiros parâmetros apresentaram correlações significativas fortemente negativas com o valor... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The objectives of this research were the determination of the texture profile of canned corned beef thermally processed and to evaluate its relationship with the sterilization value (F0) and the composition. Fourteen production batches of Campden A grade 340-g corned beef cans were selected, from which twenty-four cans of the thermal process sub-batches were retrieved. From the sub-batches, six random sample cans were taken and its content submitted to the Texture Profile Analysis (TPA) and to the composition analysis to determine the concentration of the Collagenous Connective Tissue Protein (CCTP), the Muscular Tissue Protein (MTP) concentration and the Lean Meat Content (LMC). The corned beef samples analyzed were submitted to thermal treatments at 121o C (retort steam temperature) for varying heating times, from 75 to 76 minutes and cooled at 35o C (retort water temperature) during 35 minutes, to obtain F0 values at the product center point varying from 14.8 to 20 minutes. The TPA parameters were determined in 8 points of the whole corned beef loaf of each sample, previously chilled and stabilized at 4o C temperature, to obtain hardness, fracturability, cohesiveness, elasticity, adhesiveness, springiness, gumminess, chewiness and resilience. The same sample material were then analyzed in terms of average composition of the product, resulting in concentrations in the range of 0.4 to 2.5% for CCTP, 21.7 to 25.3% for MTP and content from 102.8% to 108.0% for LMC. The treated corned beef samples analyzed showed significant differences in the means for hardness, adhesiveness, chewiness and elasticity. These parameters showed dependence with the sterilization value (F0), revealing negative strong significant correlation for F0 with hardness, gumminess and chewiness. The MTP and LMC values showed a high positive significant correlation with cohesiveness. It was observed a high... (Complete abstract click electronic access below) / Mestre
94

Characterization and application of fruit byproducts in the development of beef burger and corn extruded product / Caracterização e aplicação de subprodutos de frutas no desenvolvimento de hambúrguer bovino e extrusado de milho

Miriam Mabel Selani 17 September 2015 (has links)
This study aimed to characterize pineapple, passion fruit and mango byproducts and select the material with the greatest potential as food ingredient to be applied in two food products: beef burger and corn extruded product. Fiber was the major component present in pineapple and passion fruit byproducts (>50%), and, due to this, they showed considerable water holding capacity. The fruit byproducts had considerable phenolic content and antioxidant activity, especially the mango byproduct. The results of the microbial counts and the content of pesticides residues of the byproducts were within the limits established by the Brazilian law and were safe for food application. Due to the high fiber amount and the functional properties presented, the byproducts were explored considering this potential. Thus, the sample with the best results was selected and evaluated as partial fat replacer in beef burger and as source of fiber in a corn extruded product. The first step of the beef burger application evaluated each byproduct in four concentrations (1.0, 1.5, 2.0, and 2.5%), along with canola oil, as partial fat replacers. All byproducts improved the cooking properties of the burgers, especially the pineapple. Sensory analysis showed that color, odor and overall acceptance were not affected by the treatments. Based on the results, pineapple byproduct, at the concentration of 1.5%, was selected for further studies. Pineapple byproduct (1.5%) and canola oil (5%) were evaluated as partial animal fat replacers in low-fat beef burger. Five treatments were performed: conventional (20% fat) and four formulations with 10% of fat: control, with pineapple byproduct, with canola oil, and with pineapple byproduct and canola oil. Pineapple byproduct incorporation improved the cooking properties and the texture (shear force) and canola oil addition improved the lipid profile, without reducing the shelf life of the burgers. The quantitative descriptive analysis indicated that the use of the two fat replacers together can be an alternative choice to minimize the sensory alterations of the fat reduction. As the final step of this study, the potential application of pineapple byproduct in a corn extruded product for fiber enhancement was evaluated. During extrusion, byproduct (0, 10.5, and 21%), moisture (14, 15, and 16%) and temperature (140 and 160 °C) were evaluated. Pineapple byproduct addition decreased expansion and luminosity, while increasing redness of the extrudates compared to the control (0% byproduct/14% moisture/140 °C). When hardness, yellowness, water absorption, and bulk density were compared to the control, there was no effect of 10.5% addition on the extrudates, indicating that, at this level, pineapple byproduct could be added without promoting significant alterations in the properties of the final extruded product. The results of this study highlight the potential of pineapple byproduct in the development of new products, bringing the opportunity to convert them into value-added food ingredients. / Este estudo objetivou caracterizar subprodutos de abacaxi, maracujá e manga e selecionar aquele com maior potencial como ingrediente alimentício para ser aplicado em dois produtos: hambúrguer bovino e extrusado de milho. A fibra foi o maior componente presente nos subprodutos de abacaxi e maracujá (>50%) e, devido a isto, eles mostraram considerável capacidade de retenção de água. Os subprodutos de frutas apresentaram teor de compostos fenólicos e atividade antioxidante considerável, especialmente o de manga. Os resultados das contagens microbianas e dos teores de resíduos de agrotóxicos dos subprodutos apresentaram-se dentro dos limites estabelecidos pela legislação brasileira, estando seguros para aplicação em alimentos. Devido ao alto teor de fibra e às propriedades funcionais apresentadas, os subprodutos foram explorados considerando-se este potencial. Dessa forma, a amostra com melhores resultados foi selecionada e avaliada como substituto parcial de gordura em hambúrguer bovino e como fonte de fibras em extrusado de milho. A primeira etapa da aplicação em hambúrguer bovino avaliou cada subproduto em quatro concentrações (1,0, 1,5, 2,0 e 2,5%), juntamente com o óleo de canola, como substitutos parciais de gordura. Todos os subprodutos melhoraram as propriedades de cozimento dos hambúrgueres, especialmente o de abacaxi. A análise sensorial mostrou que cor, odor e aceitação global não foram afetados pelos tratamentos. Através dos resultados, o subproduto de abacaxi, na concentração de 1,5%, foi selecionado para estudos complementares. Subproduto de abacaxi (1,5%) e óleo de canola (5%) foram avaliados como substitutos parciais de gordura animal em hambúrguer bovino com teor reduzido de gordura. Cinco tratamentos foram realizados: convencional (20% gordura) e quatro formulações com 10% de gordura: controle, com subproduto de abacaxi, com óleo de canola, e com subproduto de abacaxi e óleo de canola. A incorporação do subproduto de abacaxi melhorou as propriedades de cozimento e a textura (força de cisalhamento) e a adição do óleo de canola melhorou o perfil lipídico, sem reduzir a vida útil dos hambúrgueres. A análise descritiva quantitativa indicou que o uso dos dois substitutos de gordura em conjunto pode ser uma alternativa adequada para minimizar alterações sensoriais da redução da gordura. Como fase final deste estudo, o potencial da aplicação de subproduto de abacaxi em extrusado de milho visando o aumento do teor de fibras foi avaliado. Durante a extrusão, subproduto (0, 10,5, 21%), umidade (14, 15, e 16%) e temperatura (140 e 160 °C) foram avaliados. A adição do subproduto de abacaxi diminuiu a expansão e a luminosidade, enquanto que aumentou a intensidade de cor vermelha dos extrusados comparados com o controle (0% subproduto/14% umidade/140 °C). Quando a dureza, intensidade de cor amarela, absorção de água e densidade foram comparadas com o controle, não houve efeito da adição de 10,5% sobre os extrusados, indicando que, neste nível, o subproduto de abacaxi pode ser adicionado, sem promover alterações significativas sobre as propriedades do produto final. Os resultados deste estudo destacam o potencial do subproduto de abacaxi no desenvolvimento de novos produtos, trazendo a oportunidade de convertê-los em ingredientes alimentícios com valor agregado.
95

Mikrotalasno stimulisana sinteza odabranih derivatanaftenskih i žučnih kiselina, ispitivanje njihove biološke aktivnosti kao i termičke i hemijske stabilnosti odabranih lekova / Microwave-assisted synthesis of selected naphthenicand bile acids derivatives, examin their biological activity as well as thermal and chemical stability of selected medicines

Vasiljević Bojana 26 September 2014 (has links)
<p>Predviđena istraživanja u ovoj doktorskoj disertaciji su usmerena u<br />pravcu iznalaženja novih, efikasnijih i bržih mikrotalasno-stimulisanih<br />metoda hemijskih transformacija koje ne uključuju prisustvo<br />katalizatora i/ili organskih rastvarača. Primenom specijalnih silicijum-karbidnih reakcionih sudova, brzina i preciznost izvođenja<br />mikrotalasno-stimulisanih transformacija prikazana&nbsp; je kroz stresne<br />studije aktivnih farmaceutskih ingredijenata u SiC&nbsp; ploči, odnosno<br />HPLC/GC vialima kao reakcionim sudovima. Ispitano je postojanje<br />netermičkih mikrotalasnih efekata i njihov značaj za precizno tumačenje<br />rezultata mikrotalasne sinteze.<br />U drugom delu ove doktorske disertacije izvr&scaron;ena jemikrotalasno-stimulisana sinteza potencijalno biolo&scaron;ki aktivnih&nbsp; supstanci iz prirodnih<br />lako dostupnih materijala kao &scaron;to su naftenske kiseline. Sintetizovani su<br />amidi i estri individualnih i prirodnih naftenskih kiselina Velebit.<br />U radu je takođe ispitana biolo&scaron;ka aktivnost sintetizovanih derivata.<br />Proučavan je uticaj prirodnih naftnih kiselina Velebit injenih derivata<br />na rast pet sojeva&nbsp; Pseudomonassp., kao i uticaj odabranih sintetisanih<br />jedinjenja na proliferaciju pet&nbsp; ćelijskih linija humanih tumora pri&nbsp; čemu<br />je kao kontrola služila jedna zdrava humana ćelijska linija.</p> / <p>Scientific research predicted in this PhD thesis isdirected to ascertainment new, efficient and faster microwave-assisted methods of chemical transformations in the absence of catalysts and/or organic solvents. Applaying special silicon-carbide&nbsp; reaction vessels, speed and accuracy of microwave-assisted transformations are ilustrated within stress testing of active pharmaceutical ingredients in HPLC/GC vials placed in SiC plate. Existence of nonthermal microwave effects and their influence on &nbsp;accurate interpretation of microwave synthesis results are also investigated.&nbsp;<br />In the second part of this thesis microwave-assisted synthesis of potentionally biologically active compounds from readily available natural materials, such as &nbsp;naphthenic acid is accomplished. Amides and esters of individual and natural naphthenic acids Velebitare synthetised. The thesis also examined the biological activity ofthe synthesized products. The effect of natural petroleum acids&nbsp; Velebitand its derivatives are examined on the growth of five strains of Pseudomonas&nbsp;sp., and the impact of selected synthesized compounds on the proliferation of five human tumor cell lines in which a healthy human cell line is tused as the control.</p>
96

Proyecto de comida semipreparada foodie box

Garcia Flores, Mirella Dayane, Mego Padilla, Manuel Antonio, Miranda Ludeña, Ciro David, Nuñez Velasquez, Flavio Jose, Ramirez Talaverano, Lady Vanessa 01 February 2021 (has links)
El presente trabajo de investigación engloba temas para el desarrollo e implementación de la marca, tiene como objetivo adquirir un rendimiento económico y sostenible en el tiempo. Foodie Box, es un proyecto de emprendimiento dedicado a ofrecer kits personalizados, incluyendo alimentos frescos y semi preparados con las cantidades adecuadas, acompañados de un recetario para mejorar la estadía y experiencia en la cocina, con el buen sabor de la comida casera. El estudio de investigación se basa en las entrevistas, ventas realizadas en la fase de experimentación, y las hipótesis planteadas para justificar la viabilidad del negocio. Por otra parte, se definió el tamaño del mercado, teniendo en cuenta el segmento y establecer las estrategias en función al producto. Las proyecciones de ventas fueron realizadas a partir del plan de Concierge, siendo el punto de partida, para una proyección a tres años. Asimismo, se presenta el plan estratégico, plan de recursos humanos, plan de responsabilidad social, plan de marketing y plan de operaciones, de forma detallada y posicionando las propuestas de valor en el mercado. Finalmente, se realizó el plan financiero para acreditar la viabilidad del proyecto, según las ventas mensuales proyectadas, los costos fijos y variables, gastos, y capital de trabajo, cabe resaltar, que los indicadores financieros fueron de ayuda para analizar la rentabilidad del emprendimiento, siendo un producto sostenible a lo largo de los años. / This research encompasses issues for the development and implementation of the brand Foodie Box, its objective is to acquire an economic and sustainable performance over time. Foodie Box is an entrepreneurial project dedicated to offering personalized kits, including fresh and semi-prepared food with the right amounts, accompanied by a recipe book to improve the stay and experience in the kitchen, with the good taste of the product being homemade. The research study is based on the interviews, sales made in the experimentation phase, and the hypotheses raised to justify the viability of the business. On the other hand, the market size was defined, taking account of our segment and establishing strategies based on our product. The sales projections were made from the concierge plan, being the starting point for a three-year projection. Likewise, the strategic plan, human resources plan, social responsibility plan, marketing plan, and operations plan are presented in detail and positioning the value proposals in the market. Finally, the financial plan was carried out to prove the viability of our project, according to the projected monthly sales, fixed and variable costs, expenses, and working capital, it should be noted that the financial indicators were helpful to analyze the profitability of our entrepreneurship, I feel that this product should be sustainable over the years to come. / Trabajo de investigación
97

Advancing Rehabilitation Research Through Characterization of Conventional Occupational Therapy for Adult Stroke Survivors with Upper Extremity Hemiparesis

Wengerd, Lauren Rachel January 2019 (has links)
No description available.
98

Phase Behaviour in Crystalline Solids : Exploring the Structure Guiding Factors Via Polymorphism, Phase Transitions and Charge Density Studies

Thomas, Sajesh P January 2013 (has links) (PDF)
The thesis entitled "Phase Behaviour in Crystalline Solids: Exploring the Structure Guiding Factors via Polymorphism, Phase Transitions and Charge Density Studies" consists of five chapters divided into two parts. A basic introductory section describes the topics relevant to the work and the methods and techniques utilized. Part A contains two chapters that discuss the structural aspects related to polymorphism, solvatomorphism, conformational preferences and phase transitions exhibited by active pharmaceutical ingredients (APIs). It also discusses the structure-property correlations in API crystal forms and the possible utility of second harmonic generation (SHG) for their bulk characterization. Part B has three chapters that discuss experimental and theoretical charge density analyses of intra-and intermolecular interactions that play structure guiding roles in some of the APIs discussed in Part A. The main focus of the present work is to characterize the interaction patterns devoid of strong classical hydrogen bonds. The case studies include multifurcated C - H …O hydrogen bonds, the “carbon bonding” and chalcogen interactions involving Se and S atoms. In addition to charge density studies, in situcryocrystallography and molecular complexation experiments have been employed to examine structural consequences of chalcogen bonding. Further, Appendices 1 and 2 describe phase transition studies on the inorganic mineral kröhnkite and its high temperature phase transitions leading to novel inorganic structural types. Part A: Polymorphism and phase behaviour in Active Pharmaceutical Ingredients (APIs) Chapter 1 discusses case studies of polymorphism, supramolecular preference sand phase transitions exhibited by active pharmaceutical ingredients (APIs). Section 1.1 deals with the polymorphism of an anti-oxidant drug candidate ebselen and its hydroxyl derivative. The potential of organoselenium compounds to form a Se…O chalcogen bonded supramolecular recognition unit (synthon) has been established in these polymorphs and its generality is substantiated with the help of a Cambridge Structural Database (CSD) analysis. Section 1.2 demonstrates the utility of the ‘chalcogen bonded supramolecularsynthon’ in generating molecular complexes of APIs. A series of salts and co-crystals of the amyotrophic lateral sclerosis drug Riluzole have been synthesized in order to evaluate the structure directing role of S…O chalcogen bonded synthon in their crystal structures. Section 1.3adescribes the generation of polymorphs and solvatomorphs of the antidepressant drug candidate fenobamand associated phase transitions. The tautomeric preference in this molecule has been rationalized from the crystal structure analysis and abinitioenergy calculations. Further, section 1.3b utilizes chemical derivatization as a means to experimentally simulate thetautomeric preference and molecular conformations in several derivatives of fenobam and thiofenobam. Section 1.4 describes the issue of solvatomorphism and the generation of the fifth solvatomorph of gallic acid, its structural complexity and temperature induced phase transitions. The ability of solvent water molecules to drive structural diversity, by forming ‘hydration synthons’,is demonstrated in this case. Chapter 2 presents a novel methodology for the detection of polymorphic impurities in APIs based on second harmonic generation (SHG).The SHG based method has been employed to polymorphic mixtures of fenobam, hydrochlorothiazide, pyrazinamide, tolbutamide, curcumin, febuxostat and nimesulide.The conventional methods such as powder X-ray diffraction (profile fitting analysis), FT-IR, Raman spectroscopy and thermal analysesto detect the presence of polymorphic impuritiesin bulk API samples are employed on the mixtures of these API samples and the impurity detection limits are compared with the proposed SHG methodology. The APIs used in these case studies were screened for their SHG efficiency using quantum chemical calculations of hyperpolarizability and HOMO-LUMO charge redistribution behaviour. Further, a correlation with the crystal symmetry, relative packing arrangement of molecules and the observed SHG efficiency have been discussed in of some of these cases. Part B: Exploring the nature and structural consequences of nonbonding interactions in molecular crystals Chapter 3 discusses the electron density features of quasi-trifurcated CH…Cl/CH…O interaction motifs leading to ‘carbon bonding’ and a trifurcated CH…O hydrogen bond motif. Section 3.1 describes the experimental and theoretical charge density analyses of quasi-trifurcated CH…Cl and CH…O motifsand investigates the existence of “carbon bonding” in solid state. The experimental charge density evidence for “carbon bonding” have been analyzed in cases of fenobam and dimethylamine: 4-hydroxybenzoic acid complex. The existence of this unconventional interaction, which roughly mimics the transition state geometry of SN2 (bimolecular nucleophilic substitution) reaction, is further established by a CSD analysis. Section 3.2 describes the experimental and theoretical charge density analyses of ferulic acid and compares the topological features associated with a trifurcated CH…O hydrogen bond motif, with corresponding strong classical OH…O hydrogen bonds. The study demonstrates the “Gulliver effect” of weak interactions in charge density terms. Charge density based interaction energy calculations via EPMM and EML methods have been utilized in this context to evaluate the relative strength of such interactions. Chapter 4 discusses the charge density features of intermolecular chalcogen bonding interactions involving selenium and sulphur atoms.Section 4.1 describes the experimental and theoretical charge density analyses of ebselen and its hydroxyl derivative. The charge density characterization of the conserved chalcogen bond synthon (discussed in chapter 1, section 1.1) has been carried out and electronic nature and geometric dependence of Se…O interactions have been explored. The mechanism of drug action of ebselen has been correlated with the experimentally observed charge density distribution around the intramolecular SeC and SeN bonds. Section 4.2 explores the homochalcogen interactions such as S…SandSe…Se in phenol analogues. In situ cryocrystallographic studies on thiophenol, selenophenol and their solid solutions are described. Veggard’s law-like behaviour observed in these solid solutions have been rationalized and the S…S and Se…Sehomochalcogen interactions have been evaluated in these liquid systems which are devoid of any other packing forces such as strong hydrogen bonds. Chapter 5 discusses the conformation locking potential of intramolecular S…O chalcogen bonding in sulfadrugs. Section 5.1 discusses conformation locking in the antibioticdrugsulfamethizole. A two pronged approach has been adopted in the study; a) generation of cocrystals and salts of sulfamethizole for the ‘experimental simulation’ of the molecular conformation, b) evaluation of charge density distribution around the intramolecular S…O interaction region in sulfamethizole. Section 5.2 describes the effect of ‘simple hybridized orbital geometry’ in the formation of intramolecular S…O chalcogen bonding. The experimental charge density analysis of the carbonic anhydrase inhibitor drug acetazolamide has been carried out and the two different intramolecular S…O geometries have been compared in terms of the charge density topology. The analysis highlights the advantage of “orbital geometry” consideration over the conventional distance-angle criteria in assessing nonbonded interactions.
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Interaction agrégats-surface. Spectrométrie de masse par temps de vol et application analytique à des études sur des médicaments et sur la météorite Paris / Cluster-surface interaction. Time of flight mass spectrometry imaging. Drugs and Paris’s meteorite analysis

Noun, Manale 08 October 2013 (has links)
Le Lebanese Atomic Energy Commission (LAEC) poursuit un programme de développement des techniques analytiques pour compléter l’analyse par faisceau d’ions (IBA). Il a décidé de s’équiper d’un spectromètre de masse couplée à l’imagerie 2D puis récemment 3D avec l’acquisition d’un spectromètre de masse IONTOF V™ équipé de deux colonnes ioniques délivrant des faisceaux d’agrégats de bismuth et d’argon. Dans ce cadre, mon sujet de thèse a porté sur l'optimisation de l’instrument nouvellement acquis pour l’analyse d’échantillons contenant des composés organiques. Les premiers sujets de recherche sont la mise au point du protocole d’analyse quantitative de médicaments en utilisant la technique « cluster-SIMS-imaging » et l’analyse de la météorite Paris pour localiser la matière organique et déterminer sa composition. Dans les deux cas une approche multi-technique a été utilisée : IBA au LAEC, µ-Raman et µ-IR autour des équipements de Soleil et µPIXE réalisée auprès de l’accélérateur AGLAE (Centre de recherche et de restauration des musées de France, C2RMF).L’analyse de médicaments a été initiée au Liban en collaboration avec un fabricant local de produits pharmaceutiques (Mediphar Laboratories) dans le but d’établir de nouveaux procédés de contrôle qualité de produits finis. Mon étude a montré la complexité du dosage de médicament due à la présence de plusieurs molécules actives (Principe Actif, PA) et de substances organiques et minérales inactives (excipients) mélangées dans des conditions secrètes. Les effets de matrice sont dominants et modifient l’émission ionique conduisant à des erreurs systématiques importantes. Cette complexité a été analysée avec l’étude du Fludinium™ possédant deux PAs. Les résultats de cette étude ont permis d’obtenir la première courbe d’étalonnage du rapport des deux PAs et de quantifier ceux-ci dans les conditions du médicament commercial. Le protocole pour effectuer cette courbe d’étalonnage et les contrôles « qualité » ont été déterminés. Ceux-ci incorporeront une analyse en profil pour contrôler l’homogénéité des échantillons et l’obtention d’étalons produits par le fabricant en suivant ses processus de fabrication. En effet, les expériences ont montré que la réalisation du médicament en laboratoire à partir de ses éléments (PAs et excipients) ne donnait pas la même réponse ionique que le médicament commercial. L’analyse de la météorite Paris a été initiée par une collaboration avec une équipe de l’Institut d’Astrophysique Spatial d’Orsay impliquée dans l’exobiologie et la recherche des premières molécules pré-biotiques dans des échantillons extraterrestres. Le but des recherches est de caractériser la matière organique représentant quelques pourcents en poids dans une matrice minérale complexe, sans utiliser des méthodes chimiques pouvant induire une modification de ces molécules. Cette étude a démontré l’intérêt de l’approche multi-technique centrée autour de la spectrométrie de masse couplée à l’imagerie ionique pour déterminer les éléments principaux de la matrice minérale et organique. L’analyse par µPIXE avec une cartographie micrométrique a permis d’attribuer les distributions d’ions moléculaires et agrégats des spectres de masse aux différents composés minéraux. Ces attributions se poursuivent avec la constitution d’une base de données de spectres de référence. La composante organique a été extraite et les premières hypothèses de composition ont été envisagées autour des HAPs (Hydrocarbure Aromatique Polycyclique), MOI (Matière Organique Insoluble) et analogues de carbone amorphe produits par irradiation UV de glaces dont les compositions en gaz représentent différentes hypothèses pour les nuages interstellaires. Les protocoles d’analyses multi-techniques établis (incorporant un suivi de l’échantillon par spectrométrie de masse et imagerie ionique) permettent le démarrage d’analyse d’autres échantillons extra-terrestres collectés sur terre ou dans l’espace. / The Lebanese Atomic Energy Commission (LAEC) is incorporated in a development program of the analytical techniques in order to complete the Ion Beam Analysis (IBA). It was decided to get a mass spectrometer coupled to 2D and recently to 3D imaging, by acquiring an ION TOFVTM system equipped with two ionic columns delivering bismuth and argon cluster beams.In this context, my thesis is focused on the optimization of the instrument, recently purchased, for the analysis of samples containing organic compounds. The first subjects of research are the development of a protocol for quantitative analysis of drugs using the « cluster-SIMS-imaging » technique and the Paris meteorite analysis to determine its composition and to localize the organic matter. In the last case a multi-techniques approach was used : IBA in LAEC, µ-Raman et µ-IR around the Soleil synchrotron equipments and µPIXE carried with the AGLAE accelerator (Centre de recherche et de restauration des musées de France, C2RMF).The drug analysis was initiated in Lebanon in collaboration with a local pharmaceutical manufacturer (Mediphar Laboratories) in order to establish new processes for quality control of the final products. My study showed the complexity of the drug quantification which is due to the presence of several active ingredients (AI) and inactive organic and minerals components (excipients) mixed in secret conditions. Matrix effects are dominant and modify the ionic emission leading to significant systematic errors. This complexity has been analyzed with the study of FludiniumTM with two active ingredients. The results of this study allowed to obtain the first calibration curves of the ratio between the two AIs and to quantify them in the commercial drug. The protocol to perform the calibration curve and the « quality» controls were determined. These incorporate a profile analysis to control the homogeneity of the samples and the obtaining standards produced by the pharmaceutical manufacturer following the same process used for the commercial drug. Indeed, the experiments have shown that the preparation of the drug in the laboratory from its elements (AIs and excipients) doesn’t give the same ionic emission as for the commercial drug.The Paris meteorite analysis was initiated by a collaboration with the Institut d’Astrophysique Spatiale d’Orsay team involved in the exobiology and the research of the first prebiotic molecules in the extraterrestrial samples. The work objective is to characterize the organic matter representing few percents in mass in a complex mineral matrix, without any chemical extraction that can induce a modification of these molecules. This study has demonstrated the interest of the multi-techniques approach centered on the mass spectrometry coupled to the ionic imaging for the determination of the main mineral and organic elements of the matrix. µPIXE analysis coupled to the micrometric mapping permits to attribute the distribution of molecular ions and clusters of the mass spectra with different mineral compounds. These attributions continue with the creation of the data base of standard spectra. The organic component was determined and the first hypotheses were considered concerning PAHs (Polycyclic Aromatic Hydrocarbon), IOM (Insoluble Organic Matter) and analogues of amorphous carbon produced par UV irradiation of ices with a gas composition representing different hypotheses for the interstellar clouds. The establish protocols for multi-techniques (incorporating a follow of the sample by mass spectrometry and ion imaging) permits to start the analysis of other extra terrestrial samples collected on earth or in space.
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Microalgae as novel ingredients for the formulation of food products

Uribe Wandurraga, Zaida Natalia 10 January 2021 (has links)
[ES] Las microalgas son organismos unicelulares fotosintéticos microscópicos que se encuentran en gran variedad de ambientes y son muy eficientes en la transformación de energía solar en biomasa. Los estudios realizados hasta el momento hacen referencia a posibles beneficios de la incorporación de microalgas en la dieta, por la mejora del sistema cardiovascular, las propiedades adelgazantes y energizantes, capacidad antioxidante, o la reducción del colesterol y los triglicéridos. La forma más habitual de consumir las microalgas es como suplemento dietético en forma de tabletas, cápsulas o polvo. La incorporación de biomasa de microalgas en productos tradicionales se ha enfrentado al reto de la aparición de colores verdes fuertes, así como su consistencia pulverulenta que puede afectar la textura y percepción del producto. Todos estos aspectos constituyen las principales áreas de mejora para conseguir un mayor grado de aceptación de productos con microalgas, y son la base del reto de este proyecto. El objetivo de la presente tesis doctoral fue el desarrollo de nuevos productos alimentarios incorporando las propiedades nutricionales de la biomasa de microalgas, incrementando o mejorando con ello, las propiedades nutricionales del alimento original. Para conseguir este objetivo se evaluaron a nivel fisicoquímico, reológico y textural, la incorporación de diferentes especies de microalgas (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina y Nannochloropsis gaditana) en distintas matrices alimentarias (productos horneados, emulsiones y extrusionados). Por otra parte, se evaluó y caracterizó la incorporación de las microalgas utilizando diferentes tecnologías como la impresión 3D o la extrusión. Además de cómo afecta la incorporación de las microalgas a los productos obtenidos, se evaluaron los aspectos nutricionales de su incorporación, en cuanto al aporte de minerales y su biodisponibilidad. Las propiedades reológicas de las masas y emulsiones enriquecidas con microalgas (Spirulina, Chlorella y Dunaliella) indicaron que su comportamiento viscoelástico fue modificado y mejorado, mostrando características aptas para este tipo de productos. La adición de microalgas (Spirulina y Chlorella) a las masas utilizadas para la impresión 3D de galletas y snacks, permitió una mejor extrusión o impresión de éstas, obteniendo muestras impresas en 3D de forma cilíndrica, más precisas en cuanto a sus dimensiones con respecto a la estructura cilíndrica diseñada. Además, las muestras impresas presentaron mayor estabilidad y resistencia, antes y después del proceso de horneado comparadas con la muestra control. Para los productos horneados, tanto para las rosquilletas como los snacks impresos en 3D, la adición de microalgas (Spirulina y Chlorella) permitió mayor estabilidad en términos de textura. Ligeros cambios en los parámetros fisicoquímicos y de expansión se produjeron por la adición de Spirulina y Chlorella en los productos extrusionados. Además, los extrusionados enriquecidos con Nannochloropsis, mostraron parámetros similares a los de la muestra de control. Todos los productos presentaron colores luminosos y apariencias innovadoras y atractivas. En cuanto a los minerales, se observó un aumento de P, K, Ca, Na, Mg, Fe y Se con la adición de Spirulina y Chlorella, junto con el aumento de la concentración adicionada de microalgas. Siguiendo la normativa sobre etiquetado nutricional de los alimentos, el enriquecimiento con microalgas en rosquilletas se puede clasificar como un alimento "rico en hierro (Fe)". De igual forma, las rosquilletas y galletas enriquecidas con microalgas pueden considerarse un alimento "alto en selenio (Se)". Además, la incorporación de Spirulina y Chlorella en las formulaciones de galletas, permitió una mayor bioaccesibilidad del contenido de P, K, Ca, Mg, Fe, Zn y Se para la absorción en el cuerpo comparado con las muestras control. / [CAT] Les microalgues són organismes unicellulars fotosintètics microscòpics. Són molt eficients a l'hora de transformar l'energia solar en biomassa. Els estudis realitzats fins ara fan referència a possibles beneficis de la incorporació de microalgues en la dieta per produir una millora del sistema cardiovascular, per presentar propietats per aprimar i donar energia, per mostrar capacitat antioxidant o per afavorir una reducció del colesterol i els triglicèrids. La forma més habitual de consumir microalgues és com a suplement dietètic en forma de tauleta, càpsula o en pols. La incorporació de biomassa de microalgues en productes tradicionals s'ha afrontat al repte de l'aparició d'un color verd fosc i d'una consistència polsosa que pot afectar a la textura i, per tant, a la percepció del producte. Aquests aspectes constituïxen les principals àrees de millora per aconseguir un major grau d'acceptació de productes amb microalgues i són la base del repte d'aquest projecte. L'objectiu d'aquesta tesi doctoral és el desenvolupament de nous productes alimentaris que incorporen les propietats nutricionals de la biomassa de microalgues, de manera que s'incrementen o es milloren les propietats nutricionals de l'aliment original. Per aconseguir aquest objectiu s'avaluaren a escala fisicoquímica, reològica i de textura la incorporació de diferents espècies de microalgues (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina i Nannochloropsis gaditana) en diferents matrius alimentàries (productes fornejats, emulsions i extrudits). D'altra banda, s'avaluà i caracteritzà la incorporació de les microalgues utilitzant diferents tecnologies com la impressió en 3D o l'extrusió. A banda de valorar com afecta la incorporació de microalgues als productes elaborats, s'avaluaren els aspectes nutricionals, pel que fa a l'aportació i biodisponibilitat de minerals. Les propietats reològiques de les masses i emulsions enriquides amb microalgues (Spirulina, Chlorella i Dunaliella) indicaren que el seu comportament viscoelàstic fou modificat i millorat, de tal manera que mostrà característiques aptes per aquest tipus de productes. L'addició de microalgues (Spirulina i Chlorella) en les masses utilitzades per a la impressió 3D de galetes i snacks permeté una millor impressió, ja que s'obtingueren mostres impreses de forma cilíndrica amb unes dimensions més precises respecte a l'estructura cilíndrica dissenyada. A més, les mostres impreses presentaren una major estabilitat i resistència abans i després del procés de fornejat en comparació amb la mostra control. Respecte als productes fornejats, l'addició de microalgues (Spirulina i Chlorella) a les rosquilletes i els snacks impresos en 3D permeté una major estabilitat en termes de textura. Lleugers canvis als paràmetres fisicoquímics i d'expansió es produïren per l'addició d'Spirulina i Chlorella en els productes extrudits. A més, els extrudits que foren enriquits amb Nannochloropsis mostraren paràmetres similars als de la mostra control. Tots els productes presentaren colors lluminosos i aparences innovadores i atractives. Pel que fa als minerals, s'observà un augment de P, K, Ca, Na, Mg, Fe i Se quan s'afegí Spirulina i Chlorella, directament relacionat amb l'augment de la concentració de microalgues. Seguint la normativa sobre etiquetatge nutricional dels aliments, l'enriquiment amb microalgues en rosquilletes ens permet classificar-les com a aliment "ric en ferro (Fe)". De la mateixa manera, les rosquilletes i galetes enriquides amb microalgues poden considerar-se un aliment "alt en seleni (Se)". A més a més, la incorporació de Spirulina i Chlorella en les formulacions de galetes, permeté una major bioaccessibiltat del contingut de P, K, Ca, Mg, Fe, Zn i Se comparat amb les mostres control. / [EN] Microalgae are microscopic unicellular and photosynthetic organisms that can be found in a wide variety of environments. These microorganisms are very efficient when transforming solar energy into biomass, due to their cellular structure, which is completely submerged in an aqueous medium, forming an adequate surface for the exchange of nutrients and gases. Microalgae compounds are now known to exhibit cardioprotective, immunomodulatory, anti-proliferative, anti-inflammatory, cognitive, neurobehavioral and antimicrobial properties, amongst others. Researchers have shown possible benefits of the incorporation of microalgae in the diet so far. The most common way to consume microalgae is as a dietary supplement in the form of tablets, capsules or powder. The incorporation of microalgae biomass in traditional products has faced the challenge of the appearance of strong green colours, as well as its powdery consistency that can affect the texture and perception of the product. All these aspects constitute the main areas for improvement the development of microalgae-based products, and they are the challenges faced of this project. The main objective of this PhD Thesis was the development of novel food products incorporating the nutritional properties of microalgae biomass, thereby increasing or improving the nutritional properties of the original food matrix. To achieve this goal, the effect of the addition of different species of microalgae (Arthrospira platensis (Spirulina), Chlorella vulgaris, Dunaliella salina and Nannochloropsis gaditana) on the physicochemical, rheological and textural properties of different food matrices (baked products, emulsions and extrudates) was evaluated. Furthermore, the effect of the incorporation of microalgae using different technologies such as 3D printing or extrusion to obtain food products was studied. In addition, how the incorporation of microalgae affects the nutritional aspects of the food products in terms of the contribution of minerals and their bioavailability was also evaluated. The rheological properties of doughs, batters and emulsions enriched with microalgae (Spirulina, Chlorella and Dunaliella) indicated that their viscoelastic behaviour was modified and improved, showing characteristics suitable for this type of products. The addition of microalgae (Spirulina and Chlorella) to the doughs and batters used for the 3D printing of cookies and snacks, allowed a better extrusion or printing behaviour. This allowed obtaining cylindrical 3D printed samples, more precise in terms of their dimensions with respect to the designed cylindrical structure. In addition, the 3D microalgae-printed sample structures presented greater stability and resistance, before and after the baking process compared to the control sample. For baked products, both for breadsticks and 3D printed snacks, the addition of microalgae (Spirulina and Chlorella) allowed greater stability in terms of texture. Slight changes in the physicochemical and expansion parameters were produced by the addition of Spirulina and Chlorella in the extruded products. In addition, the extrudates enriched with Nannochloropsis, showed similar parameters to those of the control sample. Microalgae-enriched obtained products showed bright colours with appealing appearances. Regarding minerals, an increase in P, K, Ca, Na, Mg, Fe and Se was observed with the addition of Spirulina and Chlorella, along the increase of concentration of microalgae addition. Following the regulations on nutrition labelling for food stuffs, breadstick enrichment with microalgae are a food "high in iron (Fe)" In the same way, breadsticks and cookies enriched with microalgae can be considered a "high in selenium (Se)" food. Going a step further, Spirulina and Chlorella vulgaris incorporation in cookie formulations allowed for greater bioaccessibility of P, K, Ca, Mg, Fe, Zn, and Se content for absorption in the body than control cookies. / Uribe Wandurraga, ZN. (2020). Microalgae as novel ingredients for the formulation of food products [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/158743 / TESIS

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