A comparison of the products obtained by two methods of fractionation of casein indicate that the methods do not give the same results. An electrophoretically homogeneous fraction yielded, upon hydrolysis with pepsin, at least two phosphopeptones. The one having an N/P ratio of 6.6 was shown by filter paper partition chromatography and qualitative colour tests to be composed of serine, cystine, glutamic acid, alanine, one or more of the leucines, tyrosine, and possibly valine and arginine. / Science, Faculty of / Chemistry, Department of / Graduate

This thesis focuses on the interactions between milk proteins (caseins) and tea catechins and the consequences of the interactions on the renneting properties and digestion of casein micelles as well as on the biological functionality of the mixture, as measured using intestinal cell models. The binding of epigallocatechin-gallate (EGCG) to casein micelles was quantified using HPLC and fluorescence quenching, and it was shown that a substantial amount of EGCG can be incorporated in the casein micelles. At concentrations < 2.5 mg/ml milk, most of the EGCG added to milk was associated with the caseins. The formation of EGCG-casein micelles complexes not only delayed the gelling point of milk, but they also affected the structure formation of the gels. EGCG is known to have antiproliferative activity on colon cancer cells. Although nanoencapsulation of EGCG in casein micelles may have some advantages, such as protecting this bioactive compound from degradation, it may also affect the bioavailability of EGCG. To test this hypothesis, the effect of nanoencapsulation of EGCG in casein micelles on the biological functionality of EGCG was tested by evaluating the cytotoxity and proliferation behaviour of HT-29 colon cancer cells. It was demonstrated that nanoencapsulation did not affect the bioefficacy of EGCG. Similar experiments were also carried out on rat colonic cells, a normal line and its cancerous tranformed line. For this study, nanoencapulated EGCG was subjected to in vitro digbefore absorption. The results showed that EGCG-casein binding did not affect the digestion of the milk proteins. In this case, the bioefficacy of EGCG was not diminished as well. In addition, studies on normal cell lines demonstrated the specific effect of EGCG on cancer cells, favoring normal cell survival whether EGCG was isolated or complexed with milk. These experiments bring further evidence that milk can be employed as an appropriate platform for the delivery of bioactive compounds.

Thesis (Ph.D. in Cancer Biology) -- University of Colorado Denver, 2007. / Typescript. Includes bibliographical references (leaves 182-210). Free to UCD affiliates. Online version available via ProQuest Digital Dissertations;

O INKKI é um peptídeo catiônico anfipático derivado da ?-caseina bovina, análogo ao Mastoparan, isolado do veneno da vespa Vespula lewisi. Diferentes estudos mostraram sua atividade antiproliferativa e antitumoral in vitro com citotoxidade seletiva em linhagens de células de melanoma B16F10 em relação às células normais. Em estudos In vivo, INKKI demonstrou potente ação estimuladora da atividade fagocitária de macrófagos peritoneais. Quando aplicado diretamente em tumores, reduziu a massa tumoral, diminuindo o tempo de progressão do tumor e a formação de metástases, aumentando a probabilidade de sobrevida. Neste trabalho foram investigados os efeitos in vitro do peptídeo INKKI em linhagens de células de adenocarcinoma de mama e em células normais. As linhagens de células tumorais de mama utilizadas foram MDA-231, MCF-7 e T47D humanas, mama murina de Ehrlich e, como células normais, os fibroblastos e as células endoteliais. Foram avaliadas a atividade citotóxica, a viabilidade celular, a alteração do potencial elétrico mitocondrial, os efeitos na progressão e parada do ciclo celular e a investigação da morte por apoptose. Os resultados revelaram que o peptídeo INKKI apresenta citotoxidade seletiva dose-dependente nas células tumorais, modulando negativamente o potencial elétrico mitocondrial. O índice de proliferação celular das células tratadas diminuiu, com a parada do ciclo celular na fase G0/G1. O peptídeo induziu a morte celular por apoptose, a qual demonstrou ocorrer dependente da via mitocondrial e de forma caspaseindependente. O peptídeo INKKI é um potente modulador das atividades antiproliferativa e antitumoral da linhagem de células de adenocarcinoma de mama humana MCF-7 / The INKKI is derived from the bovine hidrolisis of ?-casein, a cationic and amphipathic peptide, analogous to mastoparan peptide isolated from the venom of the wasp Vespula lewisi. In in vitro studies, INKKI showed selective cytotoxicity in melanoma tumor cell B16F10 in relation to normal cells. In the in vivo tests, INKKI peptide has been shown to be a potent stimulator of the phagocytic activity of treated macrophages and, when applied directly into tumors, reduced tumor mass, decreasing the time progression and metastasis formation, increasing the probability of survival. This work investigated the in vitro effects of tumor peptide INKKI in cell line of human breast adenocarcinoma MCF-7. The tumor cells used were lineages of human breast tumor cells MCF7, MDA-231 and T47D and murine tumor cells (Ehrlich). The normal cells used were fibroblasts and endothelial cells. The study evaluated the cytotoxic activity, cell viability, change of mitochondrial electrical potential, effects on the progression and arrest of the cell cycle and investigation of induced death by apoptosis. The results revealed that peptide presents selective dose-dependent cytotoxicity in tumor cells by modulating negatively the mitochondrial electric potential. The index of cell proliferation of cells treated declined, with the induction of cell cycle arrest at phase G0/G1. The peptide-induced cell death by apoptosis was demonstrated to occur via mitochondrial pathway and in a caspase-independent manner. The INKKI peptide is a potent modulator of antiproliferative and antitumor activities of the breast adenocarcinoma cell line

Les émulsions laitières sont des systèmes thermodynamiquement instables qui doivent résister aux contraintes technologiques (chauffage, congélation) appliquées lors de leur fabrication ou usage. Les émulsions riches en protéines de lactosérum sont particulièrement sensibles et l’emploi d’additifs alimentaires est un moyen de ralentir leur déstabilisation. Dans l’objectif d’offrir des produits 100 % lait aux consommateurs, concevoir des émulsions, riches en protéines de lactosérum, sans additifs alimentaires et stables aux traitements technologiques, constitue un réel challenge. La stratégie employée dans ce projet de thèse a été de combiner les propriétés des agrégats de protéines de lactosérum et des caséines pour stabiliser des émulsions aux cours des traitements technologiques sur une large gamme de concentration.Des émulsions ont été préparées avec des agrégats de protéines de lactosérum de structure différente et avec différents ratios agrégats/caséines. Quelle que soit leur structure, la présence d’agrégats à la surface des globules gras déstabilise l’émulsion (gélification /séparation de phase) alors que dans la phase dispersante ceux-ci sont stables aux traitements technologiques. A l’inverse, les émulsions dont la surface des globules gras est recouverte de caséines sont très stables aux traitements technologiques. Ainsi, il est possible de moduler la stabilité des émulsions riches en protéines de lactosérum aux cours des traitements technologiques en exploitant les propriétés des agrégats et des caséines et en contrôlant leur répartition entre la surface des glo / Dairy emulsions are thermodynamically unstable systems, which have to be resistant to the technological treatments (heating, freezing/thawing) applied during their manufacture or use. Whey protein-rich emulsions are particularly sensitive to technological treatments and instabilities are currently tackled by the use of non-dairy additives. With aim to offer products that are more natural to consumers (additive-free), the preparation of whey protein-rich emulsions without additive and stable during technological treatments constitutes a major challenge for dairy companies. The strategy adopted during this thesis was to combine the properties of the whey proteins aggregates and caseins in order to stabilize emulsion during technological treatments in a large range of protein concentrationsEmulsions were prepared with various whey protein aggregates and various whey protein aggregates/caseins ratio. Whatever the whey protein aggregates, their presence at the fat droplet surface destabilize the emulsions (gelation/phase separation) whereas they are stable in the continuous phase of the emulsions during technological treatments. In contrast, emulsions are extremely stable during technological treatments when caseins fully cover the fat droplet surface. The results obtained highlighted the possibility of modulating the stability during technological treatments of whey protein-rich emulsions by combining the properties of the whey protein aggregates and the caseins and by controlling their repartition between the fat droplet surface and the continuous phase of the emulsion.

Infectious diseases e.g. gastric ulcer, caries and perodontitis, are caused by bacteria in a biofilm. Adhesion of bacteria to host ligands e.g. proteins, polypeptides and glycoproteins, is a key event in biofilm formation and colonization of surfaces such as mucosa and tooth tissues. Thus, host ligands could contribute to the susceptibility to infectious diseases. The general aim of this doctoral thesis was to study the effect of phosphorylated polypeptides and gp-340 in saliva and milk on oral bacterial adhesion and aggregation. Statherin is a non-glycosylated, phosphorylated polypeptide in saliva. The polypeptide inhibits precipitation and crystal growth of calcium phosphate and mediates adhesion of microorganisms. By using a hybrid peptide construct, the domain for adhesion of Actinomyces isolated from human infections and from rodents was found to reside in the C-terminal end, and the adhesion was inhibitable. With alanine substitution the peptide recognition epitope in the C-terminal end was delineated to Q and TF, where QAATF was an optimal inhibitory peptide. In contrast, human commensal Actinomyces bound to the middle region in a non-inhibitable fashion. Gp-340 is another protein in saliva, and it is a large, multifunctional glycoprotein. Four novel size variants (I-IV) of salivary gp-340 were distinguished within individuals, and their glycoforms were characterized. All four size variants were identical in the N-terminal amino acid sequence and shared core carbohydrates. Low-glyco lung gp-340, high-glyco saliva gp-340, and size variants I-III aggregated bacteria differently. Human milk, which shares many traits with saliva, could inhibit adhesion of Streptococcus mutans to saliva-coated hydroxyapatite (s-HA), a model for teeth, in an individually varying fashion. Human milk caseins, lactoferrin, secretory IgA, and IgG inhibited the binding avidly. By using synthetic peptides the inhibitory epitope in b-casein was mapped to a C-terminal stretch of 30 amino acids. Inhibition by human milk, secretory IgA and the b-casein-derived inhibitory peptide was universal among a panel of mutans streptococci. The main conclusions are: (i) statherin mediates differential binding of commensal versus infectious Actinomyces strains with small conformation-dependent binding epitopes, (ii) salivary gp-340 has individual polymorphisms that at least affect binding of bacteria, (iii) human milk inhibits S. mutans adhesion to s-HA in an individually varying fashion, and the C-terminal end of human milk β-casein is one inhibitory component. Together these results suggest that the studied host ligands can influence the composition of the oral biofilm. Statherin may protect the host from colonization of bacteria associated with infections. Gp-340 size variants may affect functions related to host innate immune defences such as interactions with a wide array of bacteria, and human milk may have a protective effect in infants from colonization of mutans streptococci.

Artigos de couro estão associados com tendências de moda e sofisticação em produtos de consumo. No processamento do couro, a fase de acabamento consiste de um conjunto de operações e tratamentos, essencialmente de superfície, que conferem características finais ao produto. Os objetivos do acabamento são reduzir defeitos visíveis, modificar as propriedades superficiais e melhorar os atributos de uso. Nesta fase final, são aplicadas, dentre outros produtos, resinas, geralmente, poliacrilatos e poliuretanos, e algumas vezes caseínas e outros polímeros que formam filmes de recobrimento protetores sobre o couro. Nesse contexto, este trabalho visa a uma avaliação dos filmes formados com resinas comerciais utilizadas industrialmente no acabamento de couros, relacionando a composição destes materiais com características sensoriais, com resistência mecânica, através de testes de tração, com estabilidade à água ou a solvente orgânico, com análise de dureza, e através de caracterizações por infravermelho e DSC. Ensaios de tração mostraram que as resinas poliuretânicas, no geral, apresentam uma maior resistência à tração quando comparadas com resinas acrílicas, assim como os valores de tenacidade, indicando que esses filmes suportam um maior impacto para levar o material à ruptura. A adição de pigmentos diminui essa resistência, tanto em resinas acrílicas quanto em resinas poliuretânicas, enquanto que a produção de filmes compactos apresenta características intermediárias com relação aos componentes puros. Todos os filmes acrílicos testados apresentaram uma maior capacidade de alongamento. Com relação à dureza, as resinas que se mostraram mais flexíveis e com maior alongamento, foram as que apresentaram menor dureza. A estabilidade dos filmes com relação à água e solventes mostrou que os componentes solúveis em água e em solvente aumentam com a presença de pigmento e que a absorção de água é maior e de solvente é menor em filmes com pigmento, tanto para acrilatos quanto para poliuretanos. As caracterizações a partir de análise por FTIR e DSC indicaram os grupamentos químicos e picos de temperaturas característicos dos acrilatos e poliuretanos, respectivamente. / Leather goods are associated with fashion trends and sophistication in consumer products. In the leather processing, the finishing phase consists of a series of operations and treatments, essentially in surface, conferring its final characteristics. The objectives are to reduce visible defects, modify surface properties and improve the usage attributes In this final stage are applied, among other products, resins, generally polyacrylates and polyurethanes, sometimes casein and other polymers, which form protective coating films on leather. In this context, this paper evaluates the films formed with commercial polymeric resins used industrially in finishing leather, relating the composition of these materials with their sensory characteristics, with their strength by tensile testing, with its stability to water or organic solvent, with analysis of hardness and characterizations by IR and DSC. Tensile tests showed that the polyurethane resins in general have a higher tensile strength when compared with acrylic resins, as well as the toughness values, indicating that these films support a greater impact to bring the material to rupture. The addition of pigments decreases this resistance, for acrylic resins and polyurethane resins, while the production of compact film has intermediate characteristics with respect to the pure components. All acrylic films tested had a higher elongation. With respect to hardness, the resins that were more flexible and more stretching, showed the lowest hardness. The stability of the films with respect to water and solvents has shown that water soluble solvent components increased by the presence of pigment and the water absorption is higher and the solvent is lower in pigmented films to acrylates and polyurethanes. The characterizations from IR and DSC analysis indicated the chemical groups and characteristic temperatures peaks of acrylates and polyurethanes, respectively.

Artigos de couro estão associados com tendências de moda e sofisticação em produtos de consumo. No processamento do couro, a fase de acabamento consiste de um conjunto de operações e tratamentos, essencialmente de superfície, que conferem características finais ao produto. Os objetivos do acabamento são reduzir defeitos visíveis, modificar as propriedades superficiais e melhorar os atributos de uso. Nesta fase final, são aplicadas, dentre outros produtos, resinas, geralmente, poliacrilatos e poliuretanos, e algumas vezes caseínas e outros polímeros que formam filmes de recobrimento protetores sobre o couro. Nesse contexto, este trabalho visa a uma avaliação dos filmes formados com resinas comerciais utilizadas industrialmente no acabamento de couros, relacionando a composição destes materiais com características sensoriais, com resistência mecânica, através de testes de tração, com estabilidade à água ou a solvente orgânico, com análise de dureza, e através de caracterizações por infravermelho e DSC. Ensaios de tração mostraram que as resinas poliuretânicas, no geral, apresentam uma maior resistência à tração quando comparadas com resinas acrílicas, assim como os valores de tenacidade, indicando que esses filmes suportam um maior impacto para levar o material à ruptura. A adição de pigmentos diminui essa resistência, tanto em resinas acrílicas quanto em resinas poliuretânicas, enquanto que a produção de filmes compactos apresenta características intermediárias com relação aos componentes puros. Todos os filmes acrílicos testados apresentaram uma maior capacidade de alongamento. Com relação à dureza, as resinas que se mostraram mais flexíveis e com maior alongamento, foram as que apresentaram menor dureza. A estabilidade dos filmes com relação à água e solventes mostrou que os componentes solúveis em água e em solvente aumentam com a presença de pigmento e que a absorção de água é maior e de solvente é menor em filmes com pigmento, tanto para acrilatos quanto para poliuretanos. As caracterizações a partir de análise por FTIR e DSC indicaram os grupamentos químicos e picos de temperaturas característicos dos acrilatos e poliuretanos, respectivamente. / Leather goods are associated with fashion trends and sophistication in consumer products. In the leather processing, the finishing phase consists of a series of operations and treatments, essentially in surface, conferring its final characteristics. The objectives are to reduce visible defects, modify surface properties and improve the usage attributes In this final stage are applied, among other products, resins, generally polyacrylates and polyurethanes, sometimes casein and other polymers, which form protective coating films on leather. In this context, this paper evaluates the films formed with commercial polymeric resins used industrially in finishing leather, relating the composition of these materials with their sensory characteristics, with their strength by tensile testing, with its stability to water or organic solvent, with analysis of hardness and characterizations by IR and DSC. Tensile tests showed that the polyurethane resins in general have a higher tensile strength when compared with acrylic resins, as well as the toughness values, indicating that these films support a greater impact to bring the material to rupture. The addition of pigments decreases this resistance, for acrylic resins and polyurethane resins, while the production of compact film has intermediate characteristics with respect to the pure components. All acrylic films tested had a higher elongation. With respect to hardness, the resins that were more flexible and more stretching, showed the lowest hardness. The stability of the films with respect to water and solvents has shown that water soluble solvent components increased by the presence of pigment and the water absorption is higher and the solvent is lower in pigmented films to acrylates and polyurethanes. The characterizations from IR and DSC analysis indicated the chemical groups and characteristic temperatures peaks of acrylates and polyurethanes, respectively.

Made available in DSpace on 2014-06-11T19:32:16Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-12Bitstream added on 2014-06-13T20:03:24Z : No. of bitstreams: 1 stafuzza_nb_dr_jabo.pdf: 3950530 bytes, checksum: 7762a1b85de88115c5c16380df8c26e1 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O crescimento da população bubalina em território brasileiro está relacionado ao interesse dos produtores nesse animal, como uma alternativa para a produção de carne, leite e seus derivados. Diante deste panorama, torna-se necessário o aprimoramento de programas de melhoramento genético, visando a seleção de animais geneticamente superiores para a reprodução. Por essa razão, o conhecimento do genoma da espécie é de extrema valia para o setor, uma vez que gera informações necessárias à identificação e avaliação de genes associados com características de interesse econômico. Desse modo, o presente trabalho envolveu a construção de uma nova ferramenta genômica para búfalo, denominada biblioteca BAC, a qual permitirá um novo direcionamento nos estudos moleculares do genoma bubalino, destacando-se a definição da estrutura e organização de genes de interesse econômico, fornecendo informações em nível de seqüência de DNA para o entendimento dos mecanismos e regulação dos mesmos. Com a disponibilidade dessa ferramenta, as primeiras regiões a serem caracterizadas serão aquelas que contêm genes de interesse econômico, as quais se destacam as regiões com genes relacionados com produção e qualidade do leite, regiões com genes relacionados com resposta imune e adaptativa, e regiões com genes da família das lipocalinas, os quais estão envolvidos com características de produção e reprodução. Porém, para que esses genes possam ser caracterizados por meio da biblioteca BAC de búfalo, há a necessidade de gerar marcadores para identificar e isolar clones específicos para esses genes. Marcadores derivados do genoma bovino têm sido utilizados com sucesso em estudos de mapeamento do genoma bubalino, os quais podem ser uma fonte importante de marcadores. Porém, para famílias gênicas, há a necessidade da geração de marcadores específicos para búfalo... / The increase of the buffalo population in Brazil is the result of the great interest of the producers as an alternative source for the production of meat, milk and dairy products. Thus, it becomes necessary genetic improvement programs more effective, in order to select genetically superior animals for breeding. The knowledge of the buffalo genome is valuable in this regard, since it generates information to identify and evaluate genes associated with economically traits. In this project we constructed a new genomic tool for buffalo - a genomic BAC library - which can be used in molecular studies of buffalo genome especially those related with the definition of the molecular structure and organization of economically important genes. Once this genomic tool is available, the first target regions of the buffalo genome to be characterized are those containing genes related to milk production, adaptive and innate immune response, and regions lipocalin genes involved in reproduction and production traits. However, to characterize these regions using the BAC library is necessary to have molecular markers to be able to identify and isolate the specific clones. Markers derived from the bovine genome have been successfully used in buffalo genome mapping studies, showing to be an important source of markers. On the another hand, for those genes found in the genome as gene families, there is a need for buffalo specific markers. The evaluation of new markers will contribute to the characterization of those target regions of the buffalo genome, providing information about the genomic architecture of this specie when compared with other bovid

Artigos de couro estão associados com tendências de moda e sofisticação em produtos de consumo. No processamento do couro, a fase de acabamento consiste de um conjunto de operações e tratamentos, essencialmente de superfície, que conferem características finais ao produto. Os objetivos do acabamento são reduzir defeitos visíveis, modificar as propriedades superficiais e melhorar os atributos de uso. Nesta fase final, são aplicadas, dentre outros produtos, resinas, geralmente, poliacrilatos e poliuretanos, e algumas vezes caseínas e outros polímeros que formam filmes de recobrimento protetores sobre o couro. Nesse contexto, este trabalho visa a uma avaliação dos filmes formados com resinas comerciais utilizadas industrialmente no acabamento de couros, relacionando a composição destes materiais com características sensoriais, com resistência mecânica, através de testes de tração, com estabilidade à água ou a solvente orgânico, com análise de dureza, e através de caracterizações por infravermelho e DSC. Ensaios de tração mostraram que as resinas poliuretânicas, no geral, apresentam uma maior resistência à tração quando comparadas com resinas acrílicas, assim como os valores de tenacidade, indicando que esses filmes suportam um maior impacto para levar o material à ruptura. A adição de pigmentos diminui essa resistência, tanto em resinas acrílicas quanto em resinas poliuretânicas, enquanto que a produção de filmes compactos apresenta características intermediárias com relação aos componentes puros. Todos os filmes acrílicos testados apresentaram uma maior capacidade de alongamento. Com relação à dureza, as resinas que se mostraram mais flexíveis e com maior alongamento, foram as que apresentaram menor dureza. A estabilidade dos filmes com relação à água e solventes mostrou que os componentes solúveis em água e em solvente aumentam com a presença de pigmento e que a absorção de água é maior e de solvente é menor em filmes com pigmento, tanto para acrilatos quanto para poliuretanos. As caracterizações a partir de análise por FTIR e DSC indicaram os grupamentos químicos e picos de temperaturas característicos dos acrilatos e poliuretanos, respectivamente. / Leather goods are associated with fashion trends and sophistication in consumer products. In the leather processing, the finishing phase consists of a series of operations and treatments, essentially in surface, conferring its final characteristics. The objectives are to reduce visible defects, modify surface properties and improve the usage attributes In this final stage are applied, among other products, resins, generally polyacrylates and polyurethanes, sometimes casein and other polymers, which form protective coating films on leather. In this context, this paper evaluates the films formed with commercial polymeric resins used industrially in finishing leather, relating the composition of these materials with their sensory characteristics, with their strength by tensile testing, with its stability to water or organic solvent, with analysis of hardness and characterizations by IR and DSC. Tensile tests showed that the polyurethane resins in general have a higher tensile strength when compared with acrylic resins, as well as the toughness values, indicating that these films support a greater impact to bring the material to rupture. The addition of pigments decreases this resistance, for acrylic resins and polyurethane resins, while the production of compact film has intermediate characteristics with respect to the pure components. All acrylic films tested had a higher elongation. With respect to hardness, the resins that were more flexible and more stretching, showed the lowest hardness. The stability of the films with respect to water and solvents has shown that water soluble solvent components increased by the presence of pigment and the water absorption is higher and the solvent is lower in pigmented films to acrylates and polyurethanes. The characterizations from IR and DSC analysis indicated the chemical groups and characteristic temperatures peaks of acrylates and polyurethanes, respectively.