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Wedholm, Anna. "Variation in milk protein composition and its importance for the quality of cheese milk /." Uppsala : Dept. of Food Science, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/200813.pdf.
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Ekeke, Nnenna Uloma. "Gastrointestinal hormonal responses to selective milk based diets." Thesis, Queen's University Belfast, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317438.
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Sipola, Marika. "Effects of milk products and milk protein-derived peptides on blood pressure and arterial function in rats." Helsinki : University of Helsinki, 2002. http://ethesis.helsinki.fi/julkaisut/laa/biola/vk/sipola/.
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Thurgood, Andrew G. P. "NMR studies of the structure and dynamics of proteins and peptides." Thesis, University of East Anglia, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253623.
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Altmann, Karina [Verfasser]. "Generation, enrichment and characterization of bioactive oligosaccharides and peptides from milk / Karina Altmann." Bonn : Universitäts- und Landesbibliothek Bonn, 2016. http://d-nb.info/1103135198/34.
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Antonsson, Cecilia. "Mjölk, gluten och ADHD : En litteraturundersökning om mjölk och glutens påverkan hos barn med ADHD." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-31551.
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Attention Deficit Hyperactivity Disorder (ADHD) is becoming a more common diagnosis of younger children. In recent years the perception that some ingredients in our food may have a negative effect regarding the symptoms in children with ADHD has grown stronger. Children with ADHD often suffer from irritated bowel syndromes which affect their ability to digest food. This may result in malnutrition as well as a release of substances that are harmful.The purpose of this report is to compile and illustrate the knowledge of how special food, particular milk protein and gluten, may affect the symptoms of children with ADHD. Also, the report aims to evaluate if there should be changes made in Kindergarten to increase the well-being of these children. The report is a summary of research results on the effects milk protein and gluten have on children with ADHD.The majority of children with ADHD demonstrate decreased symptoms if they receive a diet without milk protein and gluten.If children with ADHD would be given a special diet excluding milk protein and gluten it is realistic to assume that their ADHD-symptoms might be reduced with a greater sense of well-being and quality of life as a result.Attention Deficit Hyperactivity Disorder (ADHD) är en allt mer vanligt förekommande diagnos hos förskolebarn. Uppfattningen om att en anpassad kosthållning kan lindra symtomen hos barn med ADHD har växt sig starkare de senaste åren. Barn med ADHD lider ofta av en irriterad tarm som har en störd matspjälkningsfunktion, vilket kan leda till att näringsämnen bryts ner ofullständigt och resulterar i näringsbrister och frisättning av ämnen som kan påverka oss negativt.Syftet med rapporten är att sammanställa och belysa kunskapen om hur kosten kan påverka symtomen hos barn med ADHD, med särskild inriktning på påverkan från mjölkprotein och gluten. Samt att belysa vilken nytta skolverksamheten kan ha av dagens forskning inom ämnet.Rapporten är en sammanställning av de forskningsresultat som finns inom ämnet ADHD-anpassad kost där mjölkprotein och gluten utesluts.Majoriteten av barn med ADHD påvisar en minskade symtom om de får en anpassad kost utan mjölkprotein och gluten.Om förskolan skulle erbjuda barn med ADHD en anpassad kost är det realistiskt att anta att deras ADHD-symtom skulle kunna minska med ett ökat välbefinnande som följd.
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Stefanutti, Erin. "ANGIOSTATIN LIKE PEPTIDES IN MILK: POTENTIAL DEVELOPMENT FOR DAIRY PRODUCTS CAPABLE OF CANCER PREVENTION." DigitalCommons@CalPoly, 2011. https://digitalcommons.calpoly.edu/theses/479.
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For the past 40 years, antiangiogenic approaches have been of major interest in the development of methods to cure and prevent cancer. Angiogenesis, the development of blood vessels from pre-existing vascularization, is essential for cancer growth and spread of metastasis through the delivery of nutrients and oxygen essential to sustain the metabolic activity of these malignant cells. Blocking access to blood will cause cancerous cells to assume a dormant state creating inactive micro-tumors innocuous to the host. Angiostatin, the internal fragment of the fibrinolytic zymogen plasminogen, has shown great potential in reducing cancer size and number of metastatic colonies in animal models. Owing to the success of these preliminary results angiostatin is currently on clinical trials. Plasminogen is known to be transferred from blood to milk during lactation. The objectives of this research were to: 1) investigate the ability of various proteases in cleaving plasminogen, both from human and bovine sources, and consequently release the angiostatin like fragment; 2) determine the anticancer activity of bovine angiostatin; 3) examine ability of the antiangiogenic fragment to survive digestion; 4) purify the fragment of interest through column chromatography. Production of angiostatin was tested through hydrolysis of plasminogen via Bacillus Polymyxa protease (or dispase I), elastase, lactic acid bacteria and Bacilli originated enzymes. Once proteases capable of angiostatin like peptide production were identified, and sequence analysis of the fragments obtained conducted to confirm that bovine angiostatin was indeed produced, ability of angiostatin, both human and bovine, in inhibiting malignant melanoma as well as colon cancer cells was evaluated in vitro. From the results obtained we can confirm that bovine angiostatin inhibitory activity on cancerous cells is similar to that observed for human angiostatin. Analysis of bovine angiostatin survival through in vitro human digestion model was also examined. Results show good possibility of angiostatin surviving digestion, even if confirmation of these results is required through further in vivo studies. Additionally, digestive enzymes such as trypsin and α-chymotrypsin showed ability in cleaving plasminogen directly to release a 25kDa fragment. Knowing that each kringle has some degree of anticancer activity it would be of interest to further study the possibility of angiostatin related fragments to be produced during milk digestion. Finally, affinity chromatography through L-lysine used to purify human angiostatin resulted to be an adequate method for bovine angiostatin purification. Preliminary results obtained from this study open a new area worth investigating to uncover the potential of using bovine angiostatin in the development of novel food products capable of cancer prevention.
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Liu, Yufang [Verfasser], and Monika [Gutachter] Pischetsrieder. "Identification and Quantification of Bioactive Peptides in Milk and Kefir / Yufang Liu ; Gutachter: Monika Pischetsrieder." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2017. http://nbn-resolving.de/urn:nbn:de:bvb:29-opus4-86084.
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Liu, Yufang Verfasser], and Monika [Gutachter] [Pischetsrieder. "Identification and Quantification of Bioactive Peptides in Milk and Kefir / Yufang Liu ; Gutachter: Monika Pischetsrieder." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2017. http://d-nb.info/1136473270/34.
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Billakanti, Jaganmohan. "Extraction of High-Value Minor Proteins from Milk." Thesis, University of Canterbury. Chemical and Process Engineering, 2009. http://hdl.handle.net/10092/3843.
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Various methods for extraction and analysis of high value minor proteins (lactoferrin, lactoperoxidase and immunoglobulins) directly from raw milk were explored. Extraction, purification and analysis of high-value minor proteins directly from milk without pre-treatment are major challenges for dairy industry, largely due to the complexity of milk and the presence of colloidal solids (casein micelles and milk fat globules). To overcome some of these challenges, this work focused on three main objectives: 1) characterization of cryogel monolith chromatography for purification of lactoferrin (LF) and lactoperoxidase (LP) directly from raw milk in single step, 2) identification and characterization of Protein A Mimetic affinity ligands for purification of immunoglobulins (Igs) from milk and 3) development and validation of a surface plasmon resonance method for simultaneous quantification of five whey proteins in multiple samples.
Results portrayed the possibility of 40–50 column volumes of various milk samples (whole milk, skim milk and acid whey) to pass through a 5 mL cryogel monolith chromatography column at 525 cm hr⁻¹ without exceeding its pressure limits if the processing temperature is maintained around 35–37°C. Ideally, this should be the milk secretion temperature. The dynamic binding capacity obtained for the cryogel matrix (2.1 mg mL⁻¹) was similar to that of the binding capacity (2.01 mg mL⁻¹) at equilibrium with 0.1 mg mL⁻¹ of lactoferrin in the feed samples. Lactoferrin and lactoperoxidase was selectively bound to the cryogel column with trivial leakage in flowthrough fractions. Lactoferrin was recovered from elution fractions with a yield of 85% and a purity of 90%. These results, together with the ease of manufacture, low cost and versatile surface chemistry of cryogels suggest that they may be a good alternative to packed-bed chromatography for direct capture of proteins from milk, provided that the binding capacity can be increased.
A Protein A Mimetic (PAM) hexapeptide (HWRGWV) peptide ligand that binds to the Fc portion of antibody molecules was explored for affinity purification of immunoglobulins from milk. The peptide has the ability to purify IgG from various milk and whey samples with a purity of greater than 85% in single step. More than 90% bound IgG was recovered with 0.2 M acetate buffer at pH 4.0 and total column regeneration was successfully achieved by 2.0 M guanidine-HCl. At 9.0 mg mL⁻¹ of IgG feed concentration, an equilibrium binding capacity of 21.7 mg mL⁻¹ and dynamic binding capacity of approximately 12.0 mg mL⁻¹ of resin was obtained. Recoveries and yields of IgG were significantly influenced by the feed IgG concentration. PAM hexamer ligand also contributed a significant amount of cross-reactivity with casein, glycomacropeptides and β-lactoglobulin proteins, however majority of these proteins were recovered in the regeneration step, except β-lactoglobulin, which co-eluted with IgG. Higher IgG concentration in feed vastly reduced the amount of cross-reactivity whilst increasing the recoveries and purities in the final product. PAM affinity ligands also showed interactions towards other classes of bovine immunoglobulins. These findings established the possibility of using PAM hexamer peptide as an alternative to conventional Protein A/G affinity chromatography for the isolation of Igs from milk in single step process.
A surface plasmon resonance (SPR) method was developed for simultaneous, quantitative determination of commercially important whey proteins in raw and processed milk samples, whey fractions and various milk-derived products, with six samples per assay. Immobilized antibody stability and reproducibility of analyses were studied over time for 25 independent runs (n=300), giving a relative standard deviation (RSD) of <4%. Immobilized antibodies showed negligible non-specific interactions (<2–4 SPR response units (RU)) and no cross-reactivity towards other milk components (<1 RU). Regeneration of immobilised antibodies with glycine at pH 1.75 was determined to be optimal for maintaining the SPR response between samples. This method compared and validated well with reversed phase high performance liquid chromatography (RP-HPLC) and standard enzyme-linked immunosorbent assays (ELISA).
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Rouy, Emilien. "Activité de peptides issus d’hydrolysats de protéines de lait sur la physiologie des cellules osseuses." Thesis, Paris, AgroParisTech, 2013. http://www.theses.fr/2013AGPT0085.
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L’ostéoporose touche principalement les femmes après la ménopause, c’est une maladie caractérisée par une détérioration de la minéralisation et de la micro-architecture de l’os. L’objectif du travail de thèse présenté ici est d’identifier une fraction protéique laitière ayant un effet stimulant sur la formation osseuse. Une telle fraction, ajoutée dans un produit ou un complément alimentaire, pourrait contribuer à réduire la perte osseuse. La première étape du projet consiste à produire les fractions laitières. Des protéines laitières (caséine ou protéines sériques) ont été digérées par des enzymes puis filtrées pour les fractionner selon leur poids moléculaire. Les fractions obtenues ont ensuite été testées sur des cultures primaires de cellules osseuses. Certaines fractions protéiques laitières ont augmenté la prolifération et la différenciation des ostéoblastes. Parmi ces fractions actives, la fraction correspondant au rétentat d’une filtration sur un filtre à 10kDa d’un hydrolysat de caséine par de la chymotrypsine a été sélectionnée pour être testée sur animaux. Cette fraction a été nommée fraction CR10. Pour étudier l’activité du CR10 in vivo sur le métabolisme osseux, un modèle de souris sous restriction protéique est mis au point. Nos études démontrent que, lorsque le régime est basé sur des protéines de soja, le passage d’un régime contenant 20% de protéines à un régime contenant 6% de protéines induit une réduction de la formation osseuse. Le traitement des souris sous restriction protéique avec du CR10 n’a eu aucun effet, ce qui signifie que le CR10 n’arrive pas à exercer son activité anabolique in vivo. En revanche, si de la caséine est donnée à la place du soja ou si de la PTH est injectée aux souris, la formation osseuse est augmentée. Ces résultats suggèrent que la fraction CR10 n’est pas un bon candidat comme fraction anabolique. En revanche, l’effet positif de la caséine par rapport au soja pourrait être exploité lors de futures études visant à mettre au point une fraction caséique ostéoanaboliqueOsteoporosis is a disease mainly affecting women after menopause, characterized by a reduced bone mineralization and a deterioration of bone micro-architecture. The aim of this thesis is to identify a milk protein fraction able to stimulate bone formation. When added to a food product, this fraction could reduce bone loss. The first task of this project was to produce the milk protein fractions. Milk proteins (casein or whey proteins) were digested by enzymes and fractionated by filtration according to their molecular weight. The fractions obtained were then tested on primary cultures of bone cells. Some of the milk protein fractions tested were able to increase proliferation and differentiation of osteoblasts. Among these active fractions, the one obtained by digestion of casein by chymotrypsin followed by filtration through a 10 kDa filter have been selected to be tested on animals. This fraction is named CR10. To study the activity of CR10 in vivo, a protein-restricted mouse model has been developed. Our studies showed that a reduction of protein in the diet from 20% to 6% impaired bone formation when the diet was based on soy protein. When these protein-restricted mice ingested the CR10 fraction, no improvement of the BMD was reported, which means that the CR10 cannot exert its anabolic activity in vivo. However, if casein is given instead of soy or if PTH is injected to the mice, bone formation is increased. These results suggest that the CR10 is not a good candidate as an anabolic fraction. However, the positive effect of casein compared to soy could be exploited in future studies aimed at finding an osteoanabolic casein fraction
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Wang, Shiping. "Peptides as amino acid sources for the synthesis of secreted proteins by mammary tissue explants and cultured mammary epithelial cells." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/39137.
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Vilela, Regina Maria. "The influence of whey peptides and fenretinide on inflammation and apoptosis in immortalized wild type and mutant [delta]F508 CFTR human tracheal epithelial cells /." Thesis, McGill University, 2006. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102227.
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Studies were conducted using cultured immortalized wild type (non-CF) and mutant (CF) DeltaF508 cystic fibrosis transmembrane conductance regulator (CFTR) tracheal epithelial cells on the anti-inflammatory impact of agents that may alter ceramide and glutathione (GSH) metabolism. The CF cells demonstrated abnormally high levels of GSH and glutathione disulfide (GSSG), which could diminish intracellular production of ceramide, a key modulator of inflammation and apoptosis. Hence, additional cell culture studies were carried out with a known inducer of in situ ceramide synthesis, N-4(4-hydroxyphenyl) retinamide (fenretinide) on interleukin (IL)-8 release, intracellular ceramide content, and cellular proliferation in both the basal state and following the inflammatory stimuli of tumor necrosis factor (TNF) -alpha. Fenretinide treatment was associated with a dose-dependent increase in the cellular content of ceramide in both CF and non CF cells. Also, an inhibition of IL-8 release in the inflammatory condition of TNF-alpha treatment was observed following fenretinide treatment in the CF cells. As hyperbaric treatment of whey proteins was previously associated with improved survivability and higher GSH content in a Pseudomonas aeruginosa murine model of cystic fibrosis (CF), the anti-inflammatory role of low molecular weight peptides (< 1kDa) generated from enzymatic hydrolysis of native and pressurized whey protein isolates (WPI) was examined. Pressure treatment of WPI was associated with an enhanced protein digestibility and an altered peptide profile following in vitro digestion. The whey peptides were tested CF and non-CF lung epithelial cells to identify for their effects on GSH metabolism. The impact of the combined treatment of fenretinide and WPH was also tested in terms of apoptosis and cytokine release in cell culture. As opposed to non-CF cells, CF cells showed a strong downtrend in release of IL-8 following the combined fenretinide and whey peptide treatment. In addition, whey peptides protected wild type epithelial cells from the apoptotic effect of fenretinide. Our results suggest the usefulness of these agents as a pharmacological treatment in CF.
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Sales, Iana Rafaela Fernandes. "Avaliação in vitro do efeito imunomodulador do leite materno de camundongos infectados pelo Schistosoma mansoni." Universidade Federal de Pernambuco, 2015. https://repositorio.ufpe.br/handle/123456789/16506.
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CAPEs
A alta prevalência de esquistossomose crônica em gestantes, bem como em mulheres em idade fértil, tem sido amplamente relatada. Esta condição materna é capaz de alterar a resposta imune do descendente em longo prazo. O presente estudo teve o objetivo de avaliar o efeito in vitro do leite materno de mães infectadas pelo Schistosoma mansoni em esplenócitos e caracterizar os peptídeos encontrados nesse leite. Para isso, camundongos fêmeas infectadas ou não, tiveram seu leite coletado no 12º dia após o parto. Os esplenócitos jovens (15 dias) e maduros (6 semanas) foram cultivados com o Leite de Mães Infectadas (LMI) e com Leite de Mães Não Infectadas (LMNI) na presença de estimulador policlonal. Além disso, foram utilizados controles experimentais: Células pulsadas na ausência (BASAL) e apenas com estimulador policlonal (MITÓGENO) e células cultivadas com LMNI adicionado de antígenos solúveis dos ovos do S.mansoni (LMNI+SEA). Posteriormente, os ensaios de citometria de fluxo foram realizados para dupla marcação: Linfócitos T (CD3+ ou CD4+) marcados com CD28, CD154, CTLA4, IL-10 ou FoxP3. Além disso, foram analisadas a expressão de CD80, CD86 e CD40 na superfície de Macrófagos (CD14) e Linfócitos B (CD45R), e ainda a expressão de IL-10 por esse último. Para a análise dos peptídeos presentes no leite materno, um gel unidimensional foi confeccionado e as bandas obtidas no LMI, LMNI+SEA e LMNI foram processados para análise por espectometria de massa. Além disso, foram realizadas análises de antígenos parasitários: SEA e SWAP (antígeno solúvel do verme adulto). Esplenócitos jovens pulsados apenas com o mitógeno apresentaram maior frequência de células CD3+CD28+ e CD45R+IL10+. A adição de LMNI manteve aumento CD3+CD28+ e levou a menor frequência de Tregs, com aumento na expressão de células CD45R+CD40+. Ao ser introduzido o SEA (LMNI+SEA) foi identificada uma menor frequência de células CD3+CD28+ e aumento na expressão de IL-10. O LMI proporcionou menor frequência de linfócitos CTLA4+ e FoxP3+, porém com produção de IL-10 e maior frequência de CD45R+/CD80+. Para os esplenócitos maduros, o LMNI e LMI levaram à menor frequência de células CD3+/CD28+ e maior CD3+/CTLA4+, respectivamente, com aumento sustentado de Treg. Contudo, o LMI diminui a presença de células B IL-10+. A adição do SEA ao LMNI manteve a diminuição de células CD3+CD28+, mas aumentou a frequência de células CD3+/CD154+. O leite de mães esquistossomóticas apresentou peptídeos relacionados à presença do S. mansoni e com variabilidade de função. Destacamos a natureza imunomodulatória dos peptídios aqui identificados (Interleucina 17F, Glutationa s Transferase) que podem atuar na imunidade, seja para antígenos do parasita ou heterólogos, no descendente previamente amamentado. Estes achados enfatizam o caráter dicotômico do leite materno: estimulador em células jovens e tolerogênico em células maduras. Esses achados são relevantes em áreas endêmicas para esquistossomose e reiteram a importância da identificação e caracterização de antígenos parasitários, bem como, uma avaliação do seu papel na interação parasito-hospedeiro no incio da vida.
The high prevalence of chronic schistosomiasis in pregnant women and women of childbearing age has been widely reported. Breastfeeding by mothers with schistosomiasis is capable of altering the long term immune response of offspring. The aim of this study was to undertake an in vitro analysis of the effect of breast milk of mothers with schistosomiasis on young and mature splenocytes and characterize the proteomics in this milk. The milk of female mice infected with Schistosoma mansoni and non-infected female mice was collected on the 12th day postpartum. Young (15 days) and mature (6 weeks) splenocytes were cultivated (24hs) with mitogen (CONTROL), added to the Milk of Infected Mothers (MIM), Milk of Non-Infected Mothers (MNIM) or Milk of Non-Infected Mothers with the addition of soluble egg antigens of parasites (MNIM+SEA), as well as those without in vitro stimulus (BASAL). Double cell labeling was performed for flow cytometry: T Lymphocytes (CD3+ or CD4+) marked with CD28, CD154, CTLA4, IL-10 or FoxP3; Macrophages (CD14) and B Lymphocytes (CD45R) marked with CD80, CD86 or CD40 on the surface and the expression of IL-10 by CD45R+ cells. For analysis of proteomics a one-dimensional gel was made and the bands obtained from MIM, MNIM, MNIM + SEA, were processed for analysis by mass spectrometry. Additionally, the parasite antigens SEA and SWAP (soluble adult worm antigen preparation) were included in the analysis. Young splenocytes pulsed only with mitogen had the greatest CD3+CD28+ and CD45R+IL10+ cell frequency. The addition of MNIM maintained an increase of CD3+CD28+ and produced the lowest frequency of Tregs, with an increase in the expression of CD45R+CD40+ cells. The introduction of SEA (MNIM+SEA) resulted in reduced CD3+CD28+ cell frequency and increased IL-10 expression. MIM resulted in reduced CTLA4+ and FoxP3+ lymphocyte frequency, although there was some IL-10 production and greater CD45R+/CD80+ frequency. MNIM and MIM resulted in the lowest frequency of CD3+/CD28+ and CD3+/CTLA4+ cell frequency, respectively, for mature splenocytes, with a sustained increase of Treg. However, MIM reduced the presence of B IL-10+ cells. The addition of SEA to MNIM maintained a reduction in CD3+CD28+ cells, but increased the frequency of CD3+/CD154+ cells. The breast milk of mothers with schistosomiasis presented peptides related to the presence of S. mansoni and variability of function. The immunomodulatory nature of the peptides identified in the present study (Interleukin 17F, Glutathione-S-Transferase) should be noted, as these can act in the immune process of breastfed offspring, whether for parasite antigens or heterologous antigens. These findings emphasized the dichotomous character of breast milk, which functions as a stimulator in young cells and is tolerogenic in mature cells, yet is capable of improving LB activation. These findings are relevant for areas in which schistosomiasis is endemic and emphasize the importance of the identification and characterization of parasite antigens and the evaluation of their role in parasite-host interaction in the early stages of life, in order to obtain a better understanding of immunoregulatory events.
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Salles, Sara Salomão. "Prospecção in silico de novos peptídeos antimicrobianos a partir de fragmentos proteolíticos de leite bovino." Universidade Federal de Juiz de Fora, 2012. https://repositorio.ufjf.br/jspui/handle/ufjf/1723.
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CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
A melhoria da qualidade da alimentação pode desempenhar efeitos fisiológicos benéficos e reduzir o risco a certas doenças. O leite contribui para a ingestão recomendada de nutrientes e promove a saúde através de seus componentes biologicamente ativos que a ele agregam inúmeras funcionalidades além da nutrição. A busca por novos antibióticos de amplo espectro de ação tem aumentado nas últimas décadas devido ao número crescente de bactérias resistentes aos antibióticos convencionais. Neste sentido, as proteínas do leite bovino, após fragmentação, podem ser promissoras fontes de peptídeos antimicrobianos (PAMs), que ficam inativos quando internalizados em uma sequência protéica maior e podem ser liberados a partir de enzimas digestivas durante o trânsito gastrointestinal. Neste trabalho, sequências protéicas provenientes do leite foram obtidas em banco de dados e sumariamente clivadas in silico por enzimas gastrointestinais (pepsina, tripsina e quimotripsina). Esta clivagem virtual disponibilizou inúmeros peptídeos que foram analisados e selecionados com relação a inúmeras características inerentes à AMPs, tais como tamanho, carga, composição, hidrofobicidade, momento hidrofóbico e estruturação. Cinco peptídeos (lactof01, lactof02, A_lacto01, serumA01 e serumA02) foram selecionados e tiveram sua estrutura tridimensional construída teoricamente por meio de modelagem molecular por homologia sendo estas validadas através de servidores web. Estes peptídeos foram sintetizados manualmente e testados in vitro contra microrganismos Gram-positivos (Staphylococcus aureus) e Gram-negativos (Escherichia coli e Klebsiella pneumoniae). Os peptídeos exibiram baixa atividade antimicrobiana. Entretanto foi verificado que lactof02 foi o mais ativo contra Gram-negativas e A_lact01 foi o mais ativo contra Gram-positivas. Os ensaios hemolíticos indicaram que os peptídeos apresentaram atividade hemolítica variável. Através da análise dos testes in vitro foi possível verificar que a hidrofobicidade global e intrínseca dos peptídeos pode ter sido determinante na modulação da atividade antimicrobiana e hemolítica.
The nutrition quality improvement may play beneficial physiological effects and also reduce the risk of certain diseases. Milk contributes to the recommended nutrients intake and could promote health through its biologically active components, adding many features to nutrition. Otherwise, the search for a new broad-spectrum antibiotic action has increased in last decades due to to the increased number of bacteria resistant to conventional antibiotics. In this view, bovine milk proteins are promising antimicrobial peptides (AMPs) sources, which are inactive when are located inside of a large protein sequence and could be released by digestive enzymes during gastrointestinal transit. Here, those peptide sequences were obtained from free databases and summarily cleaved by gastrointestinal enzymes (pepsin, trypsin and chymotrypsin). This virtual cleavage provided a wide number of peptides that were analyzed and selected according to the inherent AMPs properties, such as size, charge, composition, hydrophobicity, hydrophobic moment and structuring. Five peptides (lactof01, lactof02, A_lacto01, serumA01 e serumA02) were selected, being their three-dimensional struture construted by homology modeling and validated through web servers. These peptides were synthesized and in vitro tested against Gram-positives (Staphylococcus aureus) and Gram-negatives (Escherichia coli e Klebsiella pneumoniae) microorganims. The peptides exhibited low antimicrobial activity. Nevertheless it was found that lactof02 was the most active against Gramnegatives and A_lact01 was the most active against Gram-positives. The hemolytic assays indicated that the peptides showed variable hemolytic activity. Through in vitro analisys of tests it was possible to verify that global and intrinsic peptides hydrophobicity seems to be crucial for modulation of antimicrobial and hemolytic activities.
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Danielsson, Niemi Liza. "Host ligands and oral bacterial adhesion studies on phosphorylated polypeptides and gp-340 in saliva and milk /." Doctoral thesis, Umeå : Umeå university, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-32894.
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Yan, Li. "Mechanism of milk peptide growth factor." Thesis, University of Liverpool, 2002. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398580.
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Morato, Priscila Neder. "The effect of consuming whey proteins, their component peptides and amino acids on glucose transporters in rat muscle = Efeito do consumo das proteínas do soro do leite, componentes peptídicos e aminoácidos nos transportadores de glicose em músculos de ratos." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/254506.
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Orientador: Jaime Amaya-FarfánTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos
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Resumo: As proteínas do soro do leite apresentam propriedades nutricionais e funcionais que influenciam a modulação de funções bioquímicas e fisiológicas.Estudos têm demonstrado que as proteínas do soro do leite (PSL), principalmente na forma hidrolisada (PSLH) possuem a capacidade de aumentar os níveis de glicogênio muscular. Considerando que a captação de glicose pela célula do músculo esquelético relaciona-se diretamente à atividade de proteínas transportadoras de glicose, este estudo se propôs realizar dois experimentos para conhecer os efeitos da PSL e da PSLH e de alguns dos seus produtos de hidrólise nos transportadores de glicose em músculos de ratos. No experimento 1, o objetivo foi verificar se o consumo de PSL e PSLH modulam a concentração de transportadores de glicose GLUT-1 e GLUT-4 na membrana plasmática (MP) de células musculares de animais sedentários e exercitados. Foram utilizados 48 ratos Wistar machos divididos em dois grupos: sedentários e exercitados, e cada um desses subdivididos em outros três, de acordo com a dieta, totalizando 6 grupos (n=8 por grupo). Os animais foram mantidos por 9 dias recebendo as dietas experimentais baseadas na AIN-93G, com as seguintes fontes protéicas: caseína (CAS), utilizada como controle, proteína do soro do leite (PSL), proteína do soro do leite hidrolisada (PSLH), e o animais exercitados foram submetidos a uma única sessão de exercício a 15m/min durante 60min um dia anterior ao sacrifício. Após o período experimental os animais foram sacrificados, os transportadores de glicose no músculo, GLUT-1 e GLUT-4, foram analisados por western blot. Adicionalmente, glicogênio, aminoácidos livres plasmáticos, insulina e indicadores bioquímicos de saúde foram determinados por métodos padrões. O consumo de PSLH elevou significativamente as concentrações de GLUT-4 na MP e de glicogênio, enquanto GLUT-1, insulina e os indicadores de saúde não apresentaram alterações. Baseado nas evidências do experimento 1, de que o consumo de PSLH eleva os estoques de glicogênio muscular e que também aumenta a concentração do transportador de glicose GLUT-4 na membrana plasmática, o experimento 2 teve como objetivo identificar quais componentes da PSLH poderiam modular a translocação do transportador de glicose GLUT-4 para a MP em músculo esquelético. Foram utilizados 49 ratos Wistar machos divididos em 7 grupos (n=7), que receberam soluções orais de glicose 30% mais 0,55 g/kg de peso corpóreo os seguintes componentes da PSLH: a) glicose (controle); b) PSLH; c) L-isoleucina; d) L-leucina; e) L-leucina mais L-isoleucina; f) peptídeo Lisoleucil- L-leucina; g) peptídeo L-leucil-L-isoleucina. Após receberem as soluções, os animais foram sacrificados, o transportador de glicose GLUT-4 no músculo foi analisado por western blot. Também foram analisados glicogênio, glicemia, insulina, aminoácidos livres plasmáticos e musculares, e indicadores bioquímicos de saúde por métodos clássicos. Entre os componentes testados da PSLH, o peptídeo leucil-isoleucina e o aminoácido isoleucina se mostraram mais eficientes em translocar GLUT-4 para a MP, favorecendo a captação de glicose pelo músculo esquelético. Os resultados obtidos nos experimentos indicam que o consumo da PSLH e de seus componentes ao aumentarem a translocação de GLUT-4 para a membrana plasmática, poderiam auxiliar no tratamento ou prevenção do diabetes do tipo II
Abstract: The milk whey proteins (WP) exhibit nutritional and functional properties which result in the modulation of the biochemical and physiological functions. Studies have shown that the WP, especially those in the hydrolyzed form (WPH),has the capacity to increase muscle glycogen levels. Considering that glucose uptake by the skeletal muscle cell is directly related to the activity of the glucose transporter proteins, the present study proposed to carry out two experiments to determine the effects of WP and WPH and of some of their hydrolysis products on the glucose transporters in rat muscles. The objective of experiment 1 was to verify if the consumption of WP and WPH are able to modulate the concentration of the glucose transporters GLUT-1 and GLUT-4 in the plasma membrane (PM) of muscle cells in sedentary and exercised animals. Forty-eight male Wistar rats were used, divided into sedentary and exercised groups, each of which was sub-divided into three sub-groups according to the diet, giving a total of 6 groups (n=8 per group). The animals were maintained for 9 days on experimental diets based on AIN-93G with the following protein sources: casein (CAS) used as the control, whey protein (WP) and whey protein hydrolysate (WPH). The exercised animals were submitted to a single exercise session for 60 min at 15m/min one day prior to euthanasia. After the experimental period, the animals were euthanized, and the muscle glucose transporters GLUT-1 and GLUT-4 analyzed by western blot. In addition, glycogen, free plasma amino acids, insulin and the biochemical health indicators were analyzed by standard techniques. The consumption of WPH significantly increased the concentrations of GLUT-4 in the PM and of glycogen, whereas GLUT-1, insulin and the health indicators remained unaltered. Based on evidence from experiment 1 that the consumption of WPH raised the muscle glycogen reserves and also the concentration of the glucose transporter GLUT-4 in the plasma membrane, the second experiment was designed to identify which WPH components could modulate translocation of the glucose transporter GLUT-4 to the PM in the skeletal muscle of the animals. Forty-nine male Wistar rats were used, divided into 7 groups (n=7), who were orally fed 30% glucose solutions plus 0.55 g/kg of body weight of the following WPH components: a) glucose (control); b) WPH; c) L-isoleucine; d) L-leucine; e) L-leucine plus L-isoleucine (50:50 mixture of both amino acids); f) L-isoleucyl-L-leucine peptide or g) L-leucyl-L-isoleucine peptide. After receiving the solutions, the animals were euthanized and the GLUT-4 determined by western blot. Glycogen, glycemia, insulin, free plasma and muscle amino acids, and the biochemical health indicators were also analyzed by classical methods. Of the WPH components tested, the peptide L-leucyl-L-isoleucine and the amino acid L-isoleucine were shown to be more efficient in translocating GLUT-4 to the PM, favoring the capture of glucose by the skeletal muscle. The results obtained from these experiments indicated that the consumption of WPH and its components increased GLUT-4 translocation to the plasma membrane, and could aid in the treatment and prevention of type ll diabetes
Doutorado
Nutrição Experimental e Aplicada à Tecnologia de Alimentos
Doutora em Alimentos e Nutrição
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Frochot, Céline. "Étude d'un décapeptide à activité de type benzodiazépine issu d'une protéine du lait bovin." Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL104N.
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Récemment, le laboratoire de biosciences de l'aliment de Nancy a découvert un décapeptide issu d'une caséine du lait bovin ayant des propriétés de type benzodiazépine : Tyr-Leu-Gly-Tyr-Leu-Glu-Gln-Leu-Leu-Arg. Cette molécule produit les mêmes effets que le diazépam, une benzodiazépine classique, et a également une bonne affinité pour le récepteur GABAA des benzodiazépines. Afin de comprendre la relation existant entre la structure et l'activité du peptide son étude conformationnelle a été menée par RMN, dichroïsme circulaire et modélisation moléculaire dans un milieu micellaire eau/SDS. Le peptide adopte une structure hélicoïdale de Gly 93 à Arg 100, principalement stabilisée par un pont salin entre le carboxylate de l'acide glutamique et le guanidinium de l'arginine. Des tests de compétition entre quelques analogues du peptide et le flunitrazépam ont été réalises et l'IC50 de ces composés a été déterminée. Nous pouvons conclure que 4 acides aminés sont essentiels à l'activité biologique, Tyr 91, Glu 96, Gln 97 et Arg 100. Des pseudoanalogues du peptide ont également été synthétisés dans l'espoir d'augmenter, et l'affinité de la molécule, et sa résistance aux dégradations enzymatiques. Nous avons mis au point une stratégie de synthèse sur support solide permettant de synthétiser des azapeptides, des iminoazapeptides et des azapeptides réduits à partir d'un même précurseur semicarbazide. Cependant, un seul de ces composés conserve son affinité pour le récepteur GABAA des benzodiazépines.
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Suda, Susanne. "Atrial natriuretic peptide in mild to moderate chronic renal failure /." [S.l : s.n.], 1987. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.
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Mercer, Eric Alexander John. "Expression, characterisation and structural analysis of the putative slow voltage-dependent potassium channel minK." Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243623.
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Abd, el-Baky Hassan Mohamed Abd el-Aziz [Verfasser]. "Milk clotting using peptidases of basidiomycetes / Hassan Mohamed Abd El-Aziz Abd El-Baky." Hannover : Technische Informationsbibliothek und Universitätsbibliothek Hannover (TIB), 2011. http://d-nb.info/1017333874/34.
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Stoeckel, Marina [Verfasser]. "Shelf-stable milk products: Impact of bacterial spores, peptidases from Pseudomonas, and plasmin / Marina Stoeckel." München : Verlag Dr. Hut, 2017. http://d-nb.info/1137023791/34.
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BEZERRA, Vilma Sobral. "Caracterização e atividade biológica de peptídeos obtidos pela hidrólise enzimática de caseína do leite de cabra Moxotó (Capra hircus Linnaeus, 1758)." Universidade Federal Rural de Pernambuco, 2011. http://www.tede2.ufrpe.br:8080/tede2/handle/tede2/4608.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Dairy proteins have bioactive peptides production great potential, however, their bioactivity is achieved only after enzymatic hydrolysis, which produces substances beneficial to health when incorporated into food or pharmaceuticals. Among them, casein has been used for this purpose. This study aims to determine peptide profile and amino acid sequence of bioactive peptides derived from Moxotó goat milk casein hydrolysis, using proteolytic enzymes such as trypsin, pepsin, papain and a protease extracted from Penicillium aurantiogriseum URM 4622. Enzymatic hydrolysis was performed using a statistical experimental design, which independent variables were pH, enzyme substrate (E: S), temperature and reaction time in Moxotó goat milk casein hydrolysis. Hydrolysis products were visualized in SDS-PAGE electrophoresis. Hydrolysates subjected to ultrafiltration (cut off 3000Da) were used to determine biological properties. Antioxidant activity was evaluated by ABTS + [2,2 '-Azin-bis (3-ethylbenzothiazoline) 6-sulfonic acid] method, using the pool of peptides (permeate <3000Da; retentate >3000Da). Antimicrobial activity was determined by the Clinical and Laboratory Standards Institute. Binding through the zinc solubility of zinc in the sample by Mass Spectrometry Inductively Coupled Plasma. Peptide profile and amino acid sequences were determined by mass spectrometry MALDI-TOF-MS/MS. The best hydrolysis degree (38.27%) was obtained with pepsin enzyme pH 3.0, 1:100 E: S, temperature of 40°C and 5 hours time reaction. However, a high hydrolysis degree precluded the use of these hydrolysates for bioactive peptides obtention. Casein tryptic hydrolysates demonstrated antioxidant activity up to 3242.3 μmol.L-1TROLOX/mg peptide in retentate (> 3000Da). By papain use, we obtained an activity up to 2329.6 μmol.L-1TROLOX /mg of peptide in permeate (<3000Da). The peptides produced by P. auratiogriseum protease action showed activity from 843.17 to 2587.30 μmol.L-1of Trolox / mg of 10 and 29% peptides hydrolysates, respectively, which were compatible with natural antioxidants, such as C vitamin and α-tocopherol. Goat casein tryptic hydrolysates demonstrated antimicrobial activity against Enterococcus faecalis ATCC 6057, Escherichia coli ATCC 2508, Klebisiela pneumoniae ATCC 29665, Bacillus subtilis ATCC 6633. Casein hydrolysates showed IC50 of 4.46 mg/g for zinc binding. Mass spectrometry MALDI TOF MS\MS allowed the visualization of caprine casein peptides in permeate (<3000Da), ranging from 568 to 2923 Da. It also showed LLYQEPVLGPV and HPINHQGLSPEVPNENLLR amino acids sequences for αs1 and β-casein, respectively, from casein tryptic hydrolysates; LLYQEPVLGPV sequences of β-casein, the NPWDQVK αs2 NENLL-casein and-casein in the αS1 casein hydrolysates by papain use; LLYQEPVLGPVRGPFPI β-casein sequence from casein hydrolysates obtained by the use of P. aurantiogriseum URM 4622 protease. The casein hydrolysates bioactive properties are referent to the prevalence of hydrophobic amino acids, which possibility of their use as bioactive peptides.
Proteínas lácteas apresentam grande potencial na produção de peptídeos bioativos. A caseína se destaca na produção de bioativos. Entretanto, a sua bioatividade só é conseguida após hidrólise enzimática, ao qual se produz substâncias benéficas à saúde quando incorporados em alimentos ou produtos farmacêuticos. O objetivo deste trabalho foi o de caracterizar e a avaliar atividades biológicas e determinando o perfil peptídico e a sequência de aminoácidos dos peptídeos bioativos obtidos a partir de hidrólise da caseína do leite de cabra Moxotó, usando enzimas proteolíticas tripsina, pepsina, papaína e protease extraída de Penicillium aurantiogriseum URM 4622. A hidrólise enzimática foi realizada através de planejamento experimental estatístico, os quais as variáveis independentes foram pH, relação enzima substrato (E:S), temperatura e tempo de reação na hidrólise da caseína do leite de cabra Moxotó. Os produtos de hidrólise foram visualizados em eletroforese SDS‑PAGE. Os hidrolisados submetidos à ultrafiltração (Cut off 3000Da) foram utilizados para determição das propriedades biológicas. A atividade antioxidante foi avaliada no pool de peptídeos, permeado (<3000Da) e retentado (>3000Da) usando-se o método ABTS+ [2,2’-azino-bis (3-etilbenzotiazolin) 6-ácido sulfônico]. A atividade antimicrobiana foi determinada pelo método do Clinical and Laboratory Standards Institute. O carreamento de zinco através da solubilidade do zinco na amostra através da Espectrometria de Massa em Plasma Indutivamente Acoplado. O perfil peptídico e as sequências de aminoácidos foram determinados por espectrometria de massa MALDI-TOF-MS/MS. O melhor grau de hidrólise (38,27%) foi obtido com a enzima pepsina usando pH 3,0, E:S de 1:100, 40ºC e 5 horas de reação. Entretanto, um alto grau de hidrólise impossibilitou o uso desses hidrolisados para obtenção de peptídeos bioativos. Os hidrolisados trípicos da caseína mostraram atividade antioxidante de até 3.242,3μmol.L-1TROLOX/mg de peptídeo no retentado (>3000Da). Com o uso da papaína, obteve-se uma atividade de até 2.329,6μmol.L-1TROLOX/mg de peptídeo no permeado (<3000Da). Os peptídeos produzidos pela ação da protease produzida por P. auratiogriseum apresentaram atividade de 843,17 a 2.587,30μmol.L-1de TROLOX/mg de peptídeos para os hidrolisados com 10 e 29% respectivamente, os quais foram compatíveis a antioxidantes naturais, como a vitamina C e α-tocoferol. Os hidrolisados trípticos da caseína caprina apresentaram atividade antimicrobiana frente a Enterococcus faecalis ATCC 6057, Escherichia coli ATCC 2508, Klebisiela pneumoniae ATCC 29665, Bacillus subtilis ATCC 6633. Os hidrolisados de caseína mostraram IC50 de 4,46mg/g para carreamento de zinco. A espectrometria de massa MALDI TOF MS permitiu visualizar os peptídeos no permeado (<3000Da) da caseína caprina, na faixa de 568 a 2.923 Da. Mostraram as sequências LLYQEPVLGPV e HPINHQGLSPEVPNENLLR e da β- e αs1-caseina para hidrolisados trípticos da caseína; as sequências LLYQEPVLGPV da β-caseína, NPWDQVK da αs2-caseina e NENLL da αS1-caseína nos hidrolisados da caseína com o uso da papaína e a sequência LLYQEPVLGPVRGPFPI da β-caseina no hidrolisado da caseína com o uso da protease produzida por P. aurantiogriseum URM 4622. As propriedades bioativas dos hidrolisados da caseína referem-se à prevalência de aminoácidos hidrofóbicos, o que possibilita o uso destes como peptídeos bioativos.
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BELIN, VINCENT. "Etude des mecanismes de synchronisation et de recrutement des cellules ocytocinergiques chez la ratte allaitante." Université Louis Pasteur (Strasbourg) (1971-2008), 1986. http://www.theses.fr/1986STR13097.
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L'oxytocine responsable de l'expulsion du lait hors des alveoles de la glande mammaire (ejection de lait) est liberee de la neurohypophyse de facon pulsatile et periodique, les pericaryons sont situes dans les noyaux paraventriculaires et supraoptiques
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Bader, Lange Miranda Lu. "IN VIVO OXIDATIVE STRESS IN ALZHEIMER DISEASE BRAIN AND A MOUSE MODEL THEREOF: EFFECTS OF LIPID ASYMMETRY AND THE SINGLE METHIONINE RESIDUE OF AMYLOID-β PEPTIDE." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/117.
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Studies presented in this dissertation were conducted to gain more insight into the role of phospholipid asymmetry and amyloid-β (Aβ)-induced oxidative stress in brain of subjects with amnestic mild cognitive impairment (aMCI) and Alzheimer disease (AD). AD is a largely sporadic, age-associated neurodegenerative disorder clinically characterized by the vast, progressive loss of memory and cognition commonly in populations over the age of ~65 years, with the exception of those with familial AD, which develop AD symptoms as early as ~30 years-old. Neuropathologically, both AD and FAD can be characterized by synapse and neuronal cell loss in conjunction with accumulation of neurofibrillary tangles and senile plaques. Elevated levels of oxidative stress and damage to brain proteins, lipids, and nucleic acids are observed, as well. Likewise, aMCI, arguably the earliest form of AD, displays many of these same clinical and pathological characteristics, with a few exceptions (e.g., no dementia) and to a lesser extent.
Studies in this dissertation focused on the contributions of oxidative stress to the exposure of phosphatidylserine (PtdSer) to the outer-leaflet of the lipid membrane, how and when PtdSer asymmetric collapse contributes to the progression of aMCI, AD, and FAD, and the role played by methionine-35 (Met-35) of Aβ in oxidative stress and damage, as measured in a transgenic mouse model of Aβ pathology. Normally, the PtdSer is sequestered to the cytosolic, inner-leaflet of the bilayer by the adenosine triphosphate (ATP)-dependent, membrane-bound translocase, flippase, which unidirectionally transports PtdSer inward against its concentration gradient. Oxidative stress-induced modification of flippase and/or PtdSer, however, leads to prolonged extracellular exposure of PtdSer on the outer membrane leaflet, a known signal for both early apoptosis and selective recognition and mononuclear phagocytosis of dying cells. Within the inferior parietal lobule (IPL) of subjects with aMCI and AD, a significant collapse in PtdSer asymmetry was found in association with increased levels of both pro- and anti-apoptotic proteins, Bax, caspase-3, and Bcl-2. Moreover, a significant collapse in PtdSer asymmetry was also found in whole brain of human double-mutant knock-in mouse models of Aβ pathology, together with significantly reduced Mg2+ATPase activity, representing flippase activity, and increased levels of pro-apoptotic caspase-3. Significant PtdSer externalization corresponded to the age at which significant soluble Aβ(1-42) deposition occurs in this particular mouse model (9 months), and not of plaque deposition (12 months), suggesting that elevated levels of Aβ(1-42), together with increasing oxidative stress and apoptosis, may contribute to altered PtdSer membrane localization.
Also in this dissertation, transgenic mice carrying Swedish and Indiana mutations on the human amyloid precursor protein (APPSw,In) and APPSw,In mice carrying a Met35Leu mutation on Aβ were derived to investigate the role of Met-35 in Aβ(1-42)-induced oxidative stress in vivo. Oxidative stress analyses revealed that Aβ-induced oxidative stress requires the presence of Met-35, as all indices of oxidative damage (i.e., protein carbonylation, nitration, and protein-bound 4-hydroxy-2-trans-nonenal [HNE]) in brain of Met35Leu mice were completely prevented. Moreover, immunohistochemical analyses indicated that the Met35Leu mutation influences plaque formation, as a clear reduction in Aβ-immunoreactive plaques in Met35Leu mice was found in conjunction with a significant increase in microglial activation. In contrast, behavioral analyses suggested that spatial learning and memory was independent of Met-35 of Aβ, as Met35Leu mice demonstrated inferior water-maze performance compared to non-transgenic mice.
Differential expression and redox proteomic analyses to pinpoint proteins significantly altered by the APPSw,In and Met35Leu mutations was performed, as well. Expression proteomics showed significant increases and decreases in APPSw,In and Met35Leu mouse brain, respectively, in proteins involved in cell signaling, detoxification, structure, metabolism, molecular chaperoning, protein degradation, mitochondrial function, etc. Redox proteomics found many of these same proteins to be oxidatively modified (i.e., protein carbonylation and nitration) in both APPSw,In and Met35Leu mouse brain, providing additional insights into the critical nature of Met-35 of Aβ for in vivo oxidative stress in a mammalian species brain, and strongly suggesting similar importance of Met-35 of Aβ(1-42) in brain of subjects with aMCI and AD. Taken together, studies presented in this dissertation demonstrate the role of oxidative stress-induced alteration of PtdSer asymmetry and Met-35 in Aβ-induced oxidative stress in aMCI, AD, and FAD brain.
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Humbert, Gérard. "La protéase alcaline (plasmine) du lait : Dosage, purification et implications en technologie laitière." Nancy 1, 1986. http://www.theses.fr/1986NAN10382.
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Une première partie de ce travail consiste à mettre au point une méthode simple et rapide pour la détermination de l'activité protéasique dans les produits laitiers. Ce protocole satisfait aux conditions requises pour un laboratoire de contrôle ; il connait déjà des utilisations dans le milieu professionnel pour plusieurs activités enzymatiques. Le protocole est utilisé pour la mise en évidence de la variabilité de l'activité protéasique entre les laits individuels, pour l'estimation d'un degré de contamination bactérienne d'un lait, pour la mise en évidence d'une importante complexité du système enzymatique protéolytique présent. . . La variabilité de l'activité protéolytique endogène totale entre 26 laits individuels est due pour plus de la moitié à la variabilité du système proprement dit. La deuxième partie de ce travail concerne l'étude de l'enzyme majeure de ce système protéolytique endogène total du lait, il s'agit de la protéase alcaline analogue à la plasmine sanguine. Une étude approfondie sur le plasminogène et la plasmine d'origine sanguine montre la complexité du système enzymatique, sa fragilité, son comportement particulier en chromatographie. . . La protéase alcaline du lait est purifiée par 2 voies : l'une classique par chromatographie d'affinité sur lysine-agarose et l'autre, nouvelle, par chromatographie sur immunoadsorbant réalisée avec des antisérums obtenus sur lapins. Les 2 enzymes, du lait et du sang, sont analogues ; les différences observées sont dues à des modifications (activations) provoquées par les protocoles habituels de préparation des fractions enrichies en activité enzymatique à partir de la caséine entière. Le dernier volet de ce travail concerne l'étude de l'influence des conditions physiques et physicochimiques (PH, milieu salin, température) rencontrées en technologie laitière sur l'activité de la préparation enzymatique. Un rôle protecteur de certains constituants de la caséine entière vis-à-vis de l'action de la température est observé et conduit à entreprendre une étude de l'affinité du plasminogène pour la caséine
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Bram, Jéssyka Maria de França Monezi. "Biomarcadores em líquor e em leucócitos no transtorno depressivo maior, comprometimento cognitivo leve e doença de Alzheimer." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/5/5142/tde-28072017-134924/.
Full textAbstract:
O acelerado processo de envelhecimento tem trazido não só mudanças no perfil demográfico, mas também no perfil epidemiológico da população. Entre os problemas de saúde encontrados em idosos, merecem destaque os transtornos mentais, visto que acometem cerca de um terço dessa população, sendo os transtornos depressivos e a demência os problemas de saúde mental mais prevalentes. O transtorno depressivo maior (TDM), bem como o comprometimento cognitivo leve (CCL), tem sido associado prejuízo das funções cognitivas, além de aumentar o risco de desenvolvimento de demência, principalmente doença de Alzheimer (DA). Sendo assim, é importante que haja identificação preventiva de pessoas com maior risco para o desenvolvimento de DA a fim de proporcionar um tratamento precoce. Dessa maneira este estudo objetivou comparar os marcadores biológicos envolvidos na cascata amiloide, expressos em leucócitos e líquor, nas condições clínicas TDM, CCL, DA e controles saudáveis. Para tanto, foi determinada a expressão proteica das secretases ADAM10, BACE1 e PSEN1 e do peptídeo A? em leucócitos e líquor pelos métodos de Western Blotting, ELISA e Luminex. Ao analisarmos a expressão das secretases e do peptídeo Abeta em leucócitos não observamos diferenças estatisticamente significantes entre os grupos, exceto pela expressão da proteína PSEN1, que apresentou menores níveis em DA em relação à TDM. Em relação ao líquor, observamos uma significativa diminuição do peptídeo A? no grupo DA quando comparado aos grupos CCL, TDM e também a controles saudáveis; porém não foram observadas diferenças de expressão desse peptídeo entre CCL, TDM e controles saudáveis. Esses resultados sugerem que a matriz leucocitária, apesar de expressar os componentes desta via, sugerindo dispor da maquinaria enzimática necessária para o processamento da proteína precursora do amiloide (APP), não é a ideal para estudos sobre a cascata amiloide. Além disso, os resultados obtidos em amostras de líquor, de acordo com a casuística analisada, reforçam os dados da literatura que estabelecem a redução da concentração do peptídio Abeta no líquor como um biomarcador da DA, sem termos detectado alterações nos demais grupos estudados. Nossos resultados (negativos) em relação à expressão das APP-secretases no líquor acrescentam dados a este domínio ainda controverso da literatura. Assim sendo, mais estudos devem ser realizados para que possamos compreender melhor as vias relacionadas ao desenvolvimento da DAThe accelerated aging process has brought not only changes in the demographic profile, but also in the epidemiological profile of the population. Among the health problems found in the elderly, mental disorders are worth mentioning, since they affect about a third of this population, being the depressive disorders and dementia the most prevalent mental health problems. Major depressive disorder (MDD), as well as mild cognitive impairment (MCI), have been associated with higher levels of cognitive symptoms and increased risk of developing dementia, especially Alzheimer\'s disease (AD). Therefore, it is important to identify individuals at greater risk for the development of AD in order to provide treatment at early stages of the disease process. In this way, this study aimed to compare the biological markers involved in the amyloid cascade under the clinical conditions TDM, CCL, DA and healthy controls expressed in leukocytes and CSF. We determined the protein expression of ADAM10, BACE1 and PSEN1 and A? peptides in leucocytes and CSF using the Western Blotting, ELISA and Luminex methods. When analyzing the expression of the secretases and the A? peptide in leukocytes, we did not observe statistically significant differences between the groups, except for the expression of the PSEN1 protein, which presented lower levels in AD in relation to MDD. In relation to CSF, we observed a significant reduction of the Abeta peptide in AD when compared to MCI, TDM and also to healthy controls, but no differences in expression of this peptide were observed between MCI, MDD and healthy controls. These results suggest that the leukocytes, although expressing the key components and the enzymatic machinery necessary for the proteolytic processing of the amyloid precursor protein (APP), may not represent an adequate biological matrix for studies addessing the amyloid cascade. In addition, results obtained in CSF samples, according to the analyzed series, reinforce the literature data that establish the reduction of A? peptide concentration in CSF as a biomarker of AD, without detecting alterations in the other groups studied. Our (negative) results in relation to the expression of APP-secretases in CDescriptors: MSF add data to this still controversial domain of the literature. Therefore, more studies should be done so that we can better understand the pathways related to the development of AD
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El, Bari Nezha. "Étude de l'antigénicité de la caséine B et de ses produits de dégradation : Mise au point du dosage de la caséine B dans le lait par immunonéphélémétrie à supports microparticulaires." Nancy 1, 1989. http://www.theses.fr/1989NAN10055.
Full textAbstract:
Ce travail s'appuie sur la connaissance de l'antigénicité de la caséine béta pour réaliser deux objectifs, d'une part l'évaluation de la faisabilité d'un dosage différentiel de produits de dégradation, caséine Gamma 2 ou PP5, par rapport à la protéine native, et d'autre part la mise au point du dosage de celle-ci dans le lait par une technique d'immunodosage originale : l'immunonéphélémétrie à supports microparticulaires. L'étude de l'antigénicité de ces protéines bénéficie de l'application au lait de la technique de "Western blotting", dont on confirme le pouvoir analytique puissant, le fin pouvoir discriminant, la spécificité élevée et la grande adaptabilité
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Wang, Li-Jie, and 王儷潔. "Production of Hydrophobic Peptides from Goat Milk." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/py7fvx.
Full textAbstract:
碩士國立宜蘭大學
生物技術與動物科學系動物科學碩士班
102
Proline-rich peptides (PRP), with specific proline sequence and high amount of hydrophobic amino acids, hase been shown to interfere with β-amyloid (Aβ) hydrophobic aggregation, lower blood pressure and cholesterol, etc. To produce hydrophobic peptides, the amino acid sequences of common food proteins such as casein, whey protein, soy protein and ovalbumin, were searched and compared. β casein was found to have the highest amount of PRP, and goat milk contains more β casein than cow milk does. Therefore, goat milk casein was selected for PRP production. Casein from rennet coagulation was hydrolyzed with trypsin with the result that the hydrophobic peptide aggregated affecting the efficiency of hydrolysis. Further treatment with prior stretching of casein at high temperature did not improve the hydrolysis efficiency. Since casein exists as micelle which composed of more than ten thousands casein molecules, it is resonable that dissociation of the casein micelles might enhance the enzymatic hydrolysis. Addition of 30 mM EDTA or 200 mM citric acid, as well as application of ultrasound (20 kHz 50 W) could dissociate the casein micelle, while increasing pH was not effective. The micelle dissociated casein was subjected to trypsin hydrolysis, and the results confirmed the improved efficiency, with the ultrasound treatment the best. Previously, monoclonal antibody (mAb) against spicific PRP sequence was generated in our laboratory. The mAb was used to detect the casein hydrolysate, and the molecular weight was below 6.5 kDa. The PRP was further extracted with different concentration of methanol or ethanol to increase the hydrophobicity. Amino acid analysis of the ethanol extracted PRP showed 59.46% of hydrophobic amino acids, with 17.91% Proline. This research demonstrated that trypsin digestion of goat milk casein could produce high amount of hydrophobic proline-rich peptides.
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Elfahri, Khaled. "Anticarcinogenic Peptides Released from Milk Proteins by Lactobacillus Strains." Thesis, 2018. https://vuir.vu.edu.au/36844/.
Full textAbstract:
Bioactive compounds released by proteolytic cleavage of milk proteins during milk fermentation have a role beyond their nutritional importance. The first research chapter in this thesis assessed the proteolytic activity of Lactobacillus helveticus strains ASCC 953, ASCC 474, ASCC 1188 and ASCC 1315, and their ability to release bioactive compounds with antioxidative and in vitro anticarcinogenic properties during incubation at 37°C in reconstituted skim milk. The performance of these strains was not affected by the pH decline during fermentation. Soluble extracts of milk fermented by L. helveticus strain ASCC 474 showed the highest free radical (1,1-diphenyl-2-picrylhydrazyl) (DPPH) scavenging activity after 12 h of fermentation; this was followed by a significant reduction of activity at 24 h compared with the other strains and control (untreated milk). Skim milk fermented by L. helveticus contained compounds with anti-colon cancer activity at levels that differed throughout fermentation. Growth inhibition activity (19.03–50.98%) was greatest in the extract obtained after 12 h of fermentation but had markedly declined (5.40–9.94%) by the end of fermentation. L. helveticus ASCC 1315 released compounds into the skim milk supernatant that exerted greater growth inhibition (50.98%) on the HT-29 colon cancer cell line than did the other strains. More importantly, these compounds had no significant inhibitory effect on normal, primary colon cells T4056. Although these results suggest that milk fermented by L. helveticus may release bioactive compounds with important multifunctional properties, the characteristics and activities of these compounds appear highly strain and fermentation time dependent.
The second research chapter aimed to evaluate the effects of 28 days of cold storage on the release of antioxidative peptides in milk fermented by L. helveticus strain 1315 (L. 1315). Additional types of bioactivity including angiotensin-converting enzyme (ACE)
inhibition and antimicrobial activities were also assessed. Further, samples were subjected to in vitro digestion to assess the fate of peptides during gastrointestinal (GI) passage. The antioxidative properties of fermented milk exerted significantly higher radical scavenging activity using DPPH, ABTS●+ 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) reducing power and hydroxyl radical (●OH) assays after 14 days than at other time points, and were time dependent. However, these bioactivities diminished after exposure to in vitro digestive enzymes. Samples with the highest antioxidative activity were fractionated and purified, revealing the presence of nine peptides derived from beta casein (β-CN), as identified using liquid chromatography–tandem mass spectrometry (LC–MS/MS). The peptides KVLPVPQKAVPYPQ and SQSKVLPVPQKAVPYPQ exhibited the highest scavenging activity, in a dose-dependent manner.
The last research chapter in this thesis describes the isolation and identification of potential antiproliferative peptides from milk fermented by L. helveticus 1315 on HT-29, and evaluation of the antioxidant and anti-colon cancer activities of these peptides after in vitro GI digestion. The mechanism of anti-colon cancer activity (apoptotic activity, caspace-3 and cell cycle arrest) was also assessed. A peptide fraction derived from fermented milk after 14 days of cold storage at 4oC had high anti-colon cancer activity on HT-29 cells using the MTS (3-(4,5-dimethylthiazol-2-yl)-5-(3- carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) assay. Among the nine peptides identified in the fraction, KVLPVPQKAVPYPQ and SQSKVLPVPQKAVPYPQ derived from β-CN exhibited the highest antiproliferative activity. These two peptides were further subjected to in vitro GI digestion to determine their stability. The antioxidant activity of digested peptides was also assessed using DPPH and ABTS●+ assays, which revealed increased antioxidant activity and antiproliferative activity in HT-29 cancer cells through induction of apoptosis resulting in G2/M cell cycle
arrest. These results indicate that these peptides and their derivatives after digestion have potential physiological effects that may be harnessed to manage oxidation-related diseases and disorders including cancers.
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Elfahri, Khaled. "Release of bioactive peptides from milk proteins by lactobacillus species." Thesis, 2012. https://vuir.vu.edu.au/21473/.
Full textAbstract:
Proteolytic activity is very important characteristic of Lactic Acid Bacteria (LAB) They
produce therapeutic benefits and also increase physiological activity of cultured dairy
products by liberating a number of biologically active peptides. The main aim of this project
was to determine the release of bioactive peptides from milk proteins by selected
Lactobacillus species.
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Chen, Tai-Jung, and 陳臺榕. "Isolation and Identification of Bioactive Peptides of Whey from Fermented Milk." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/73348338110129158220.
Full textAbstract:
碩士國立臺灣海洋大學
食品科學系
92
二、英文摘要 The commercial whole and skim milk powder was fermented with mixed two lactic acid bacteria (AB) and addition of Protease F at 430C for 5 hrs. The effect of whey from lactic acid bacteria fermented milk on Inhibitory activity against angiotensin I-converting enzyme and antihypertensive effect were investigated. When lactic acid bacteria and Protease F was added then fermented 5 hrs, the peptide content of whey increased from 2.1 to 32.8 mg/g and the IC50 value decreased from 0.708 to 0.266 mg/ml. After 15 days to stroage at 80C, the IC50 value decreased from 0.266 to 0.147 mg/ml. The whey was fractionated by gel filtration using Sephadex G-15 column. The fractionated product of peptide with molecular weight 534 - 364 Da and below than 100 Da showed the highest inhibitory efficiency ratio (IER) being 1329 and 1384 %/ mg/ml, respectively. The whey (contained 0.5% (w/v) NaCl) as drinks was administrated to spontaneously hypertensive rat (SHR) for 8 weeks. After 4 weeks oral administration of whey , the systolic blood pressure (SBP) was significantly lower than water group (contained 0.5% (w/v) NaCl) .The average SBP decreased 15.9 mmHg after 8 weeks oral administration.
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Fatah, Bashir Ahtesh. "Anti-hypertensive (Angiotensin converting enzyme-inhibitory) peptides released from milk proteins by proteolytic microorganisms and enzymes." Thesis, 2016. https://vuir.vu.edu.au/32314/.
Full textAbstract:
This study was carried out to examine proteolytic activities of probiotic lactic acid
bacteria (LAB) in different media and antihypertensive properties as influenced by,
fermentation time, strain type and supplementation with or without an enzyme
(Flavourzyme®). Lactobacillus casei (Lc210), Bifidobacterium animalis ssp12 (Bb12),
Lactobacillus delbrueckii subsp. bulgaricus (Lb11842) and Lactobacillus acidophilus
(La2410) were propagated in 12 % reconstituted skim milk (RSM) or 4 % whey protein
concentrate (WPC) with or without supplementation (0.14 %) of Flavourzyme® for 12 h
at 37°C.
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Ho, Chin-Han, and 何金翰. "Identification, isolation and bioactivity of short peptides in mammary gland secretion of dairy cows after milk stasis." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/98994955293997066333.
Full textAbstract:
碩士國立中興大學
動物科學系所
95
Peptides released from casein by trypsin, pepsin, or Lactobacillus hydrolysis exhibit immunostimulatory, antihypertension, antimicrobial and opioid-like functions. Milking cessation induces within-gland protease activities and casein hydrolysis. As a consequence, the present study was proposed to isolate and characterize immunomodulatory peptides from dry secretion of dairy cows. Mammary dry secretions were collected from Holstein cows at weeks 0, 1, 2, and 3 after drying off, using regular milk (2-3 month postcalving) as a control. Whey protein and proteose peptones were prepared by defatting and ultracentrifugation. Bradford-protein quantitation, electrophoretic separation, and casein immunoblotting were applied to analyze compositional changes of mammary secretions after drying off. Mammary dry secretions (week 1 after drying off) and regular milk were ultrafiltrated through 10 kDa size exclusion membranes and the 10 kDa permeates were assayed for their immunomodulatory effects using phorbol 12-myristate 13-acetate (PMA)-stimulated chemiluminescence of bovine blood polymorphonuclear leukocyte (PMN). Reversed-phase highperformance liquid chromatography (RP-HPLC), matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF) and liquid chromatography-electrospray ionization/tandem mass spectrometry (LC-ESI/MS/MS) were used in further separation and characterization of mass and sequence. Results showed that total protein concentration of mammary secretions were positively correlated (r2 = 0.99) to weeks after milk stasis, and it was significantly greater (P < 0.001) than that of regular milk except for week 0. Conversely, concentration and proportion of casein in mammary secretions were negatively correlated (r2 = 1 and 0.88, respectively) with weeks after drying off, they were significantly lower (P < 0.05 and P < 0.001, respectively ) than those of regular milk except for week 0. Electrophoretic results indicate that contents of α-lactalbumin, β-lactoglobulin and soluble casein of mammary secretions decreased, while contents of lactoferrin, BSA and IgG increased after drying off. Densitometeric scanning results suggest that the proportion of proteose peptones of mammary secretions after drying off was greater than that of regular milk (2.60%) and peaked at week 1 (15.78%). Western blot using anti-casein antibody showed that casein-derived peptides increase prominently and peaked at week 1 after drying off. Bioactivity studies showed that 10 kDa permeates of mammary dry secretions significant by (P < 0.05) inhibited the response of PMN to PMA. RP-HPLC separation resolved the 10 kDa permeates of both mammary dry secretions and regular milk into three fractions, according to MALDI-TOF, fraction 1 of mammary dry secretions and regular milk contains 1764.17 Da and 1337.76 Da as the major component of respectively, and fraction 3 contains 1046.60 Da as the major component of both mammary dry secretions and regular milk. Peptide sequencing by LC-ESI/MS/MS revealed 236 types of β-casein-derived sequences and 4 types of β-LG-derived sequences in 10 kDa permeates of mammary dry secretions. Meanwhile for regular milk, 64 types of sequences are derived from β-casein, 5 types of sequences are derived from β-LG and 2 types of peptides derived from BSA. There are 4 identified sequences in mammary dry secretions match with known bioactive peptides, including β-casein f60-68 and f191-209 with antihypertensive bioactivity, β-casein f193-202 with antihypertensive and immunomodulatry bioactivity, and β-casein f193-209 with antihypertensive, immunomodulatry and antimicrobial bioactivity. However, none of the sequences identified in the 10 kDa permeates of regular milk matches with any known bioactive peptides. Extensive database searching suggested still some sequences are different from know bioactive peptides by merely 1 to 2 amino residues, such as β-casein f60-68 of mammary dry secrtions and β-casein f60-67 of regular milk, similar to opioid-like peptides β-CN f60-70 (mainly f60-66 and f60-70), and β-casein f1-24 of mammary dry secretions, similar to caseinophosphopeptide β-casein (f1-25) with 4 phosphoserin. This study clearly shows that milk protein hydrolysis in mammary gland of cows after drying off released many potential bioactive peptides, which may directly involve in mammary tissue involution and remodeling or, alternatively, through resorption, exert systemic effects to facilitate drying up procedure. Further studies are warranted to explore the fate and function of respective peptides.
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Elawadli, Inas. "Investigations into the Effects of Lactobacilli on Murine Dendritic Cells." Thesis, 2012. http://hdl.handle.net/10214/3908.
Full textAbstract:
Lactic acid bacteria (LAB) are of interest because of their potential to modulate immune responses. The effects of LAB range from regulation to stimulation of the immune system. It has been reported that LAB affect health via two main mechanisms: directly through physical interactions between LAB and cells of the immune system, and indirectly through the products of these bacteria. The studies presented in this thesis examine the direct and indirect effects of LAB on the immune system specifically on murine dendritic cells (DCs).
Mouse DCs (in form of the DC2.4 cell line) were treated in vitro with a fraction of bovine milk fermented with Lactobacillus helveticus-2 (LH-2) or three synthetic peptides identified within the fermented milk fraction. Cell culture supernatants were analyzed for presence of tumor necrosis factor (TNF)-α and interleukin (IL)-6 to determine the effects of LAB on DC activation. The results of this study showed that the ability of the milk derived fraction and the synthetic peptides to induce DC activation and production of pro-inflammatory cytokines was limited, suggesting that these peptides may induce regulatory immune responses.
A series of studies was performed in vitro to investigate the effects of six LAB species and strains, (LH-2), Lactobacillus acidophilus-5 (La-5), Lactobacillus acidophilus-115 (La-115), Lactobacillus acidophilus-116 (La-116), Lactobacillus acidophilus-14 (La-14), and Lactobacillus salivarius, on maturation and activation of DC2.4. Production of TNF-α, IL-6 and IL-10 by DCs was determined after treating cells with live LAB. The expression of DC maturation markers, CD80 and CD40, was also measured using flow cytometry after stimulation with LAB. In addition, the expression of toll-like receptors (TLRs) 2, 4 and 9 by DCs stimulated with LAB was measured. Our results revealed that LAB act differentially on pro-inflammatory and anti-inflammatory cytokine production and induction of co-stimulatory molecules by DCs. Specifically, L. salivarius was found to be the most effective LAB to induce pro-inflammatory cytokine production and expression of co-stimulatory molecules. Moreover, La-14, La-116 and La-5 induced moderate maturation and activation of DCs. On the other hand, LH-2 and La-115 are the least likely lactobacilli to induce DC response. In conclusion, various strains and species of LAB can differentially regulate DC activation and maturation, raising the possibility that these microbes can influence and steer immune responses of the host.
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Голдаєвич, Тетяна Василівна, and Tetiana Vasylivna Holdaievych. "Виділення біоактивних фосфосеринових пептидів з білків молока." Master's thesis, 2020. http://elartu.tntu.edu.ua/handle/lib/33667.
Full textAbstract:
Кваліфікаційна робота складається із вступної частини, основної, висновків та пропозицій виробнитцву, переліку літературних джерел та додатків. Загальний обсяг роботи містить 72 сторінки, 10 таблиць і 12 рисунків. Список використаної літератури складється з 70 найменувань, в тому числі 25 іноземних.
Дослідження на здобуття освітньо-кваліфікаційного рівня магістра за спеціальністю 181 «Харчові технології» – Тернопільський національний технічний університет імені Івана Пулюя, Тернопіль,2020.
В роботі встановлювали оптимальні умови pH, співвідношення ензимного препарату і субстрату, концентрацію панкреатину для отримання біоактивних фосфосеринових пептидів з протеїнів молока. У роботі використовували методи визначення концентрації білків, титрованої кислотності, pH, електрофорез та гель-фільтраціюQualification work consists of an introductory part, main, conclusions and proposals for production, a list of references and appendices. The total volume of work contains 72 pages, 10 tables and 12 figures. The list of used literature consists of 70 items, including 25 foreign ones.Research on education and qualification level of Master in the specialty 181 «Food technology» Ternopil National Technical University named Ivan Pulyuy, Ternopil, 2020. The work established optimal pH conditions, the ratio of enzyme preparation and substrate, the concentration of pancreatin to obtain bioactive phosphoserine peptides from milk proteins. Methods for determining protein concentration, titratable acidity, pH, electrophoresis and gel filtration were used.
Анотація Вступ Мета і завдання роботи 1. Огляд літератури 1.1. Пептиди та їх значення 1.1.1. Поняття про пептиди 1.1.2. Хімічний синтез пептидів 1.1.3. Природні пептиди та їх значення 1.2. Отримання білкових гідролізатів 1.2.1. Загальні відомості про білкові гідролізати 1.2.2. Методи гідролізу білків 1.2.3. Додавання білкових гідролізатів у продукти харчування 1.2.4. Використання продуктів на основі гідролізату молочного білка при харчовій алергії дітей раннього віку 1.3. Отримання природніх біоактивних пептидів шляхом протеолізу білків молока 1.3.1. Білковий склад молока. Біологічні функції білків молока 1.3.2. Отримання біоактивних пептидів казеїну та сироваткових білків молока 1.3.3. Казоморфіни і казок сини – агоністик й антагоністи оплатних рецепторів 1.3.4. Казокініни – пептиди з антигіпертензивною активністю 1.3.5. Антитромботичні пептиди казеїнового походження 1.3.6. Імуномодуляторні пептиди 1.3.7. Лакторфіни – пептиди з опіоїдною дією 1.3.8. Вплив казеїнових фосфосеринових пептидів на засвоєння міренальних речовин 2. Матеріали і методи досліджень 2.1. Матеріали та реактиви 2.2. Визначення кислотності титрованої 2.3. Визначення pH 2.4. Визначення концентрації білків 2.5. Електрофорез у ПАГ 2.6. Гель-фільтрація 3. Результати власних досліджень та їх обговорення 3.2. Встановлення значення pH для протеолізу фосфосеринових пептидів 3.3. Визначення оптимальних концентрацій ферментного препарату для отримання фосфосеринових пептидів 4. Охорона праці та безпека в надзвичайних ситуаціях 4.1. Охорона праці 4.2. Безпека в надзвичайних ситуаціях Висновки Список використаної літератури Додатки Апробація результатів магістерської роботи
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Кутянська, Наталія Степанівна, and Nataliia Kutianska. "Отримання природних біоактивних пептидів з β-казеїну молока з проектуванням цеху з виробництва масла вершкового з переробкою маслянки та знежиреного молока." Master's thesis, 2021. http://elartu.tntu.edu.ua/handle/lib/36886.
Full textAbstract:
у цій кваліфікаційній роботі спроєктовано план цеху по виробництву
200-300 слів
масла вершкового (способом збивання) потужністю 35 т/зм, незбираного молока м.ч.ж. 3, 6 %.
В ній міститься: вступ, розрахунково-пояснювальна записка, графічна, науково-дослідна частини
та розділ з охорони праці та безпеки в надзвичайних ситуаціях.
У вступі описано характеристику вершкового масла, його користь і властивості.
У розрахунково-пояснювальній записці зілюстровано технологічні схеми та проведено опис
технологій, розрахунки сировини, готової
продукції, підбір та розрахунок технологічного обладнання, розрахунок виробничих площ необхідних
для виробництва вершкового масла. Передбачено схему технологічного виробництва знежиреного
пастеризованого молока, масла “Селянське” (72,5%), ”Бутербродне” (70%), маслянки свіжої та напою з
маслянки (дієтичної). Підібрано технологічне обладнання відповідно до кількості перероблювальної
сировини з урахуванням вимог інструкції по
визначенню виробничих потужностей підприємств молочної промисловості.
На графічних листах показано схему напрямків переробки сировини, план цеху по виробництву
масла, апаратурно-технологічну схему, графік організації виробничих процесів та переріз виробничого
цеху.
У науково-дослідній частині описано будову та властивості казеїнів, а саме β-казеїну, та методи
та способи дослідження казеїнів.
У частині про охорону праці та безпеку в надзвичайних ситуаціях описано шляхи
взаємодії роботодавця з працівником та представлення безпечних умов праці для усіх
підлеглих з дотриманням усіх вимог та пожежної безпеки.in this qualification work the plan of shop on production is projected: 200-300 слів butter (whipping method) with a capacity of 35 t per shift of whole milk with fat content of 3,6%. It contains: introduction, an explanatory note, а graphic, research part and а section on labor protection and safety in emergencies. The introduction describes the characteristics of butter, its benefits and properties. The calculation-explanatory note illustrates technological schemes and describes technologies, calculations of raw materials, finished products, selection and calculation of technological equipment, calculation of production areas required for the production of butter. The scheme of technological production of skimmed pasteurized milk, butter with fat content of 72.5% and 70%, fresh buttermilk and buttermilk drink (dietary) is provided. The technological equipment is selected in accordance with the amount of processing raw materials, taking into account the requirements of the instructions for determining the production capacity of the dairy industry. The graphic sheets show the scheme of directions of raw material processing, the plan of the shop for butter production, the hardware-technological scheme, production processes organization graph and the transversal cross section of the production shop. The research part describes the structure and properties of caseins, namely β-casein, and methods and research methods of caseins. The section on labor protection and safety in emergencies describes the ways in which the employer interacts with the employee and provides safe working conditions for all subordinates in compliance with all requirements and fire safety
АНОТАЦІЯ ВСТУП 1 ТЕХНІКО-ЕКОНОМІЧНЕ ОБҐРУНТУВАННЯ 2 ТЕХНОЛОГІЧНА ЧАСТИНА 2.1 Технологічні розрахунки виробництва запроєктованого асортименту 2.1.1 Вихідні дані та схема переробки сировини 2.1.2 Сировинно-продуктовий розрахунок 2.2 Вибір та обґрунтування технологічних процесів і режимів виробництва 2.2.1 Вимоги до сировини та характеристика загальних операцій виробництва молочних продуктів 2.3 Забезпечення технологічного процесу виробництва запроєктованого асортименту 2.3.1 Підбір технологічного обладнання 2.3.2 Розрахунок площ виробничих і допоміжних приміщень 3 НАУКОВО-ДОСЛІДНА ЧАСТИНА 3.1 Аналітичний огляд літературних джерел 3.1.1 Загальне уявлення про казеїн 3.2.2 Будова і властивості β-казеїну 3.2 Мета, об’єкт, предмет та методи дослідження 3.3 Результати досліджень 3.3.1 Гомогенний β-казеїновий субстрат з казеїнових міцел 3.3.2 Отримання активної низькомолекулярної фракції пептидів з продуктів гідролізу β-казеїну 4 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ 4.1 Охорона праці 4.2 Безпека в надзвичайних ситуаціях ВИСНОВКИ СПИСОК ВИКОРИСТАНИХ ЛІТЕРАТУРНИХ ДЖЕРЕЛ
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Берекета, Віта Петрівна, and Bereketa V. P. "Гідроліз протеїнів сироватки молока протеазами тваринного походження." Master's thesis, 2019. http://elartu.tntu.edu.ua/handle/lib/30086.
Full textAbstract:
Захист відбудеться 27 грудня 2019 р. о 900 годині на засіданні екзаменаційної
комісії №18 у Тернопільському національному технічному університеті імені Івана
Пулюя за адресою: м. Тернопіль, вул. Танцорова, 2, навчальний корпус №5,
аудиторія №14.Берекета В.П. Гідроліз протеїнів сироватки молока протеазами тваринного походження. 181 «Харчові технології» – Тернопільський національний технічний університет імені Івана Пулюя. – Тернопіль, 2019. В ході виконання дипломної роботи було проведено гідроліз протеїнів сироватки молока протеазами тваринного походження, а саме трипсином, хімотрипсином, панкреатином. Було порівняно динаміку гідролізу концентрату сироваткових білків за дії різних протеолітичних препаратів. Виявлено, що найбільшою протеолітичною активністю, серед використаних в досліді препаратів, володіє хімотрипсин. Проведено електрофоретичний аналіз фракційного складу протеїнів, завдяки якому представлений типовий поділ білкових фракцій сироватки молока. Визначено молекулярно-масовий розподіл отриманих поліпептидів і пептидів під час гідролізу в кожному секторі хроматограми завдяки проведенню гель-фільтрації реакційної суміші на сефадексі G-50. Проведено електрофорез в ПААГ протеїнових фракцій концентрату сироваткових білків для визначення фракційного складу проб, які брали на встановлених етапах гідролізу (0 хв, 60 хв, 120 хв і 180 хв). Також розраховано залишкову кількість нерозщепленого β-лактоглобуліну і α-лактальбуміну після 120 хвилин гідролізу. Ключові слова: ГІДРОЛІЗ БІЛКІВ, ЕЛЕКТРОФОРЕЗ, ГЕЛЬ-ФІЛЬТРАЦІЯ, ГІДРОЛІЗАТИ ПРОТЕЇНІВ СИРОВАТКИ МОЛОКА, БІОЛОГІЧНО АКТИВНІ ПЕПТИДИ.
Bereketa V.P. Lactoserum proteins hydrolysis by proteases of animal origin. 181«Food technology»– Ternopil Ivan Puluj National Technical University. – Ternopil, 2019. During the course of diploma milk whey protein`s hydrolys was conducted with proteases of animal origin, namely trypsin, chymotrypsin, pancreatin. The dynamics of hydrolysis of whey protein concentrate by the action of various proteolytic drugs was compared. Chymotrypsin was found to have the highest proteolytic activity among the drugs used in the experiment. The electrophoretic analysis of the fractional composition of proteins was carried out, by which a typical separation of the protein fractions of milk whey was presented. The molecular weight distribution of the resulting polypeptides and peptides during hydrolysis in each sector of the chromatogram was determined by gel filtration of the reaction mixture on Sephadex G-50. Conducted electrophoresis in PAАG protein fractions of whey protein concentrate to determine the fractional composition of samples taken at the established stages of hydrolysis (0 min, 60 min, 120 min and 180 min). Also, the residual amount of unbranched βlactoglobulin and α-lactalbumin after 120 minutes of hydrolysis was calculated. Keywords: PROTEIN HYDROLYSIS, ELECTROPHORESIS, GEL FILTRATION, MILK PROTEIN WHEY PROTEIN HYDROLYSATES, BIOLOGICALLY ACTIVE PEPTIDES.
Реферат……… Вступ…… Мета і завдання роботи…….. Розділ 1. Огляд літератури……… 1.1. Загальна характеристика білків сироватки молока….. 1.2. Використання протеїнів сироватки в харчових технологіях… 1.3. Гідролізати білків сироватки……… 1.4. Біологічно активні пептиди білків сироватки………. Розділ 2. Матеріал і методи досліджень……........ 2.1. Характеристика концентрату сироваткових білків ….. 2.2. Визначення концентрації білків спектрофотометричним методом.. 2.3. Визначення протеолітичної активності спектрофотометричним методом…………… 2.4. Гель-фільтрація……..... 2.5. Електрофорез………..... Розділ 3. Власні дослідження…… 3.1. Результати досліджень продуктів протеолізу концентрату сироваткових білків…….. 3.1.1. Порівняння динаміки протеолізу концентрату сироваткових білків за дії різних протеолітичних препаратів…… 3.1.2. Гель-фільтрація продуктів протеолізу концентрату сироваткових білків на сефадексі G-50…….. 3.1.3. Електрофорез в поліакриламідному гелі протеїнових фракцій концентрату сироваткових білків…….... 3.2. Обговорення результатів протеолізу концентрату сироваткових білків…… Розділ 4. Обґрунтування економічної ефективності виробництва гідролізатів сироваткових білків………… Розділ 5. Охорона праці…………. 5.1. Відповідальність посадових осіб і працівників за порушення законодавства про охорону праці……………. 5.2. Основні положення державного соціального страхування від нещасного випадку на виробництві та професійного захворювання…… Розділ 6. Безпека в надзвичайних ситуаціях………… Розділ 7. Екологія………… Висновки і пропозиції виробництву……. Список використаної літератури ………. Апробація результатів магістерської роботи…
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Wu, Ling-Tsai, and 吳鈴彩. "Establishment of an optimal pasteurization condition of fresh milk by the peptide content from protein hydrolysis in vitro." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/41773484110993331486.
Full textAbstract:
碩士東海大學
畜產與生物科技學系
93
Milk is a highly nutritious food, and must be pasteurized to destroy all the pathogenic and microorganisms in order to extend shelf life. However, the different pasteurization conditions could induce physicochemical changes in milk. This study was intended to establish an optimal pasteurization condition of milk using response surface methodology by the peptide content from protein hydrolysis in vitro. The first factor temperature (X1) and the second factor holding time (X2) of response surface were located through preliminary study. Then X1 and X2 were used as the center point of central composite rotatable design in order to establish an optimal pasteurization condition of fresh milk. The physicochemical properties of fresh milk processed from the optimal pasteurization condition were then compared with market milk. Results suggested that temperature (X1) of 81℃ and holding time (X2) of 20 seconds, were used as center point for central composite rotatable design. Fresh milk pasteurized by 81℃ for 20 seconds had the highest peptide content. The alkaline phosphatase and lactoperoxidase activity tests were negative of fresh milk pasteurized by 81℃ for 20 seconds. The L*, b* value and titratable acidity of fresh milk pasteurized by 81℃ for 20 seconds were significantly lower (P<0.05) than market milk. In addition, pH value, available lysine content, undenatured whey protein content and peptide content were significantly (P<0.05) higher than market milk. The electrophoresis showed that fresh milk pasteurized by 81℃ for 20 seconds had more undenatured whey protein than market milk. The overall acceptability of fresh milk pasteurized by 81℃ for 20 seconds in sensory evaluation was among different market milk. Therefore, temperature of 81℃ and holding time of 20 seconds was the optimal pasteurization condition of fresh milk.
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CHEN, CHIA-LING, and 陳佳伶. "The Study of Goat Milk-Derived Proline-Rich Peptide in Promoting Neural Plasticity and Its RAGE-binding Ability." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/7mcyz3.
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Torres, D. "Gelificação térmica de hidrolisados enzimáticos de proteínas do soro de leite bovino : comportamento de sistemas aquosos mistos péptidos-polissacarídeos." Master's thesis, 2005. http://hdl.handle.net/1822/4234.
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Dissertação de mestrado em Biotecnologia, Engenharia de Bioprocessos.De acordo com as estimativas mais recentes produzem-se mundialmente cerca de 286 milhares de toneladas de soro de leite por dia. O soro produzido diariamente pode providenciar, em média, 2,4 milhares de toneladas de proteínas que, potencialmente, podem satisfazer as necessidades proteicas diárias a cerca de 35 milhões de pessoas. Durante muito tempo o soro foi encarado como um resíduo industrial ou produto com valor comercial residual. Só nas três últimas décadas foram desenvolvidos processos de separação que permitem obter ingredientes alimentares com alto teor proteico a partir do soro de leite. As proteínas do soro de leite bovino estão entre as mais equilibradas fontes de aminoácidos da dieta humana; para além disso, foram já descritas muitas actividades biológicas, essenciais para o desenvolvimento harmonioso da cria, com repercussões benéficas também no ser humano. Muitas dessas propriedades estão encriptadas nas moléculas proteicas manifestando-se após proteólise que pode ocorrer durante o processo de digestão ou durante o processamento enzimático e/ou fermentativo. A tripsina, enzima seleccionada para o trabalho desenvolvido, revela-se uma enzima interessante para a libertação de péptidos bioactivos, dada a sua especificidade, mas também para o aumento da digestibilidade e diminuição da alergenicidade das proteínas do soro de leite bovino (capítulo 1). As proteínas do soro podem ser usadas numa grande variedade de aplicações na indústria alimentar. Uma das funcionalidades das proteínas resulta da capacidade que possuem de responder a alterações ambientais alterando a sua conformação nativa e, por agregação, formar redes elásticas tridimensionais – gelificação. Os géis conferem estrutura, textura e estabilidade aos alimentos; possibilitam, ainda, a retenção de grandes quantidades de água e outras pequenas moléculas dentro da matriz alimentar (capítulo 2). No capítulo 3 do trabalho que se apresenta, estudaram-se as alterações do comportamento reológico (a baixa deformação) que ocorrem durante o processo de gelificação por aquecimento de suspensões de proteínas de soro, a pH neutro e força iónica de 220 mM. As propriedades reológicas dos géis finais foram estudadas em função da concentração de proteínas e do grau de hidrólise enzimática a que, previamente, as proteínas do soro de leite foram sujeitas. O aumento do grau de hidrólise reduz drasticamente a capacidade de gelificação das proteínas do soro e, ao contrário da variação da concentração, altera o balanço de forças que suportam a estrutura tridimensional do gel, provavelmente, diminuindo a contribuição das ligações covalentes e hidrofóbicas e aumentando a contribuição das pontes de hidrogénio. No capítulo 4, estudaram-se as alterações do comportamento reológico que ocorrem durante o processo de gelificação por aquecimento de sistemas mistos de proteínas de soro (nativas ou hidrolisadas) e polissacarídeos neutros (galactomananos), a pH neutro e força iónica de 220 mM. Para os vários sistemas estudados, as propriedades reológicas dos géis finais foram estudadas em função da concentração de polissacarídeos. Recorrendo a técnicas microscópicas (microscopia óptica e microscopia confocal de varrimento laser), verificou-se que, da incompatibilidade termodinâmica entre os dois tipos de biopolímeros, resultou uma separação de fases do tipo segregativo. Este fenómeno, por ser simultâneo ao processo de gelificação, condiciona fortemente as propriedades reológicas dos géis, pois, se por um lado favorece a concentração da fase proteica gelificante, por outro, diminui a conectividade dessa mesma fase. A quantificação da massa de água (e solutos), excluída durante o processo de gelificação (sinérese), permitiu verificar que a presença de polissacarídeos diminui a severidade do fenómeno.
Accordingly to the last estimates, the daily production of milk whey is about 286 thousand tons. The produced whey can provide 2.4 thousand tons of proteins that, potentially, can assure the daily protein requirements of about 35 million people. In the past, whey was looked upon as an industrial residue or a low value product. Only in the last three decades separation processes were developed that allow the production of food ingredients with high protein content from milk whey. Proteins from bovine milk whey are between the more equilibrated human dietary sources of amino acids; they have been described as possessing many essential biological activities which are important for the harmonious development of the calf and have also beneficial repercussions for humans. Many of these bioactivities are encrypted in the native protein molecules and are only revealed after proteolysis during the natural digestion process or during enzymatic and/or fermentative treatments. For this work, trypsin was selected to hydrolyse whey proteins since, due to its specificity, trypsin is an interesting enzyme for the liberation of bioactive peptides and, also, for the improvement of protein digestibility and for decreasing protein allergenicity (chapter 1). Whey proteins can be used for a wide range of industrial food applications. One of proteins functionalities results from their capacity to respond to changes in their physicochemical environment by modifying their native conformation and forming, after aggregation, tridimensional elastic networks – gelling. Gels confer structure, texture and stability to food products; they also allow the retention of large quantities of water and other small molecules inside the food matrix (chapter 2). In the 3rd chapter of the present work, the changes in the rheological behaviour during the heat-induced gelling process of whey protein dispersions were studied by small deformation rheology (neutral pH and ionic force 220 mM). The rheological properties of the final gels were studied as a function of protein concentration and as a function of the degree of enzymatic hydrolysis. Hydrolysis reduces dramatically the gelling ability of whey proteins and alters the balance of the different forces that sustain the elastic network, probably, increasing the proportion of hydrogen bonds and decreasing the proportion of covalent and hydrophobic interactions. In the 4th chapter, the changes in the rheological behaviour during the heat-induced gelling process of mixed systems of whey proteins (native or hydrolysed) and neutral polysaccharides (galactomannans) were studied at neutral pH and ionic force 220 mM. The rheological properties of final gels were studied as a function of polysaccharide concentration. Using microscopic techniques (optical microscopy and confocal laser scanning microscopy), thermodynamic incompatibility between the two polymers, inducing segregative phase separation, was observed. When phase separation and gelling processes occur simultaneously the rheological properties of mixed gels are greatly influenced because phase separation favour the protein gelling phase concentration but, at the same time, decreases its connectivity. The quantification of the water (and solutes) excluded during the gelling process (syneresis) permits to verify that, when polysaccharide is present during the gelling process, syneresis is less severe.
Fundação para a Ciência e a Tecnologia (FCT) - Projecto (POCTI/QUI/36452/2000) - Instituto de Ciências e Tecnologia Agrárias e Agro-Alimentares.