The diploma thesis deals with usage of wheat bran as a source of high-quality proteins. Every year mill industry produces large amounts of by-products. These by-products are constituted by wheat bran. There is a big effort to use these type of materials within a circular economy. Wheat bran contains about 14–18 % proteins which appears to be a good component for valorisation. It is possible to extract proteins from bran according to their behaviour in the range of pH. Proteins are soluble in alkaline pH and can be precipitated around their isoelectric point. The final treatment of precipitated proteins is lyophilisation. The next step is characterisation of the product. There are a few parameters to analyse: purity of the isolate, amino acid profile, composition of minerals, water contain etc. Interest in nutrition is on the rise not only by professional sportsman. This isolated product could serve as a potential protein supplement.

Ziel dieser Arbeit war die Untersuchung der antigenen Eigenschaften aktueller Isolate (PPV-143a und PPV-27a) des porzinen Parvovirus (PPV). Des Weiteren sollten die Virulenzeigenschaften dieser Isolate sowie zweier Virusstämme (PPV-NADL-2 und PPV-IDT [Master Seed Virus]), die zur Produktion von inaktivierten Vollvirus-Vakzinen genutzt werden, bestimmt werden. In der in vitro-Studie wurden die untersuchten PPV-Isolate sowie ein weiteres Isolat (PPV-Challenge [Engl.]) zur Herstellung von Hyperimmunseren im Kaninchen und - nach experimenteller Infektion von Sauen (s.u.) – zur Herstellung von Postinfektionsseren genutzt. Die Seren wurden im Neutralisationstest gegen die verschiedenen Isolate geprüft und eine Kreuzneutralisation bewertet. Das Serum-IDT (MSV) zeigte generell eine begrenzte Neutralisation gegen die heterologen PPV-Isolate. Des Weiteren ergab die Untersuchung, dass alle Seren gegen das Isolat PPV-27a als Testvirus einen geringeren Neutralisationstiter aufwiesen als gegen die anderen Isolate. Interessanterweise wurde PPV-27a durch homologe Antiseren deutlich schlechter neutralisiert als alle anderen getestete Viren. Dieser offensichtliche „Immune Escape“ wurde bei den Seren aller beiden Kaninchen und aller drei Sauen gesehen. Die experimentellen Infektionen erfolgten bei 12 tragenden Jungsauen am 40. Trächtigkeitstag (3 Tiere pro Isolat PPV-143a, PPV-27a, PPV-NADL-2, PPV-IDT [MSV]). Es konnten neben dem Serum der infizierten Sauen fetale Gewebeproben von Lunge und Niere sowie Nabelvenenblut von insgesamt 157 Feten aus diesen Trächtigkeiten untersucht werden. Zur Antikörperbestimmung wurde der HAH-Test angewendet. Spezifische Antikörper konnten bei den Feten jeder Infektionsgruppe (PPV-143a, PPV-27a, PPV-IDT [MSV]) und PPV-NADL-2) detektiert werden. Somit konnte eine transplazentare Übertragung für alle PPV-Isolate gezeigt werden. Der Antigennachweis erfolgte durch Untersuchung der Hämagglutination aus dem Gewebe beziehungsweise nach Anzucht des Erregers in Zellkultur durch Bewertung des cytopathischen Effekts und Bestätigung durch direkte Immunfluoreszenz. Der Virusnachweis gelang ausschließlich bei den Feten der Gruppe Sauen die mit PPV-27a infiziert wurden. Die fetale Mortalitätsrate der Feten der Infektionsgruppe PPV-27a lag bei 85 % und war signifikant höher im Vergleich zu den anderen Infektionsgruppen (5-18 %). Schlussfolgernd konnte in vivo lediglich für PPV-27a eine Virulenz nachgewiesen werden. In vitro zeigte sich nur für PPV-27a ein differenziertes Kreuzneutralisations-Verhalten. Diese Ergebnisse deuten darauf hin, dass das Isolat PPV-27a tasächlich eine neue antigene Variante des porzinen Parvovirus darstellt, gegen die derzeit verfügbare Impfstoffe möglicherweise nur unvollständig schützen.

Two Experiments were conducted to investigate the effect of iron status and iron source on iron bioavailability using the rat model. Beef was proportionally mixed with spinach (Experiment I) or soy protein isolate (Experiment II) to test if meat enhances the absorption of iron from spinach or SPI. Five diets with the iron from meat:spinach (or SPI) ratios of 100:0, 75:25, 50:50, 25:75 and 0:100 were prepared and fed to rats. FeS04 was used as a reference. Two trials of rats were used in Experiment I. In trial I, half of the rats were made severely iron deficient (Hb 6.3 g/dl) and the other half mildly iron deficient (Hb 8.8 g/dl). In trial II, half of the rats were depleted to severe iron deficiency and the remainder were not depleted (Hb 11.3 g/dl). Hemoglobin regeneration efficiency (HRE), apparent absorption and 59Fe absorption were compared. The HREs were 41, 53 and 36% (spinach); 42, 51,and 44% (beef) and 73, 66 and 46% (FeS04) in severely, mildly iron-depleted and healthy rats and 56 and 42% (SPI) in iron-depleted and healthy rats, respectively. Iron depletion stimulated iron absorption. This effect was very significant for rats fed a FeS04 supplemented diet and lessened for rats fed diets containing beef, spinach or SPI as the iron source. Spinach and soy protein isolate were good iron sources both having similar iron bioavailabilities as beef. Beef ~as a good iron source, as noted in other reports; however, enhancement of meat on absorption of iron from spinach and SPI did not occur. Hemoglobin regeneration efficiency is a simple, accurate and definitive method for measuring effects of iron source and iron status on iron bioavailability. Apparent absorption gives similar values to HRE. However, it requires meticulous iron analysis and has more potential for errors. Extrinsic radioisotope tagging is an easy method, but there is evidence of possible incomplete exchange of radio tracer with iron in food. The different absorption pattern between FeS04 and food iron suggests a third iron pool, highly soluble iron salt, in addition to heme and nonheme iron complex pools.

Having access to clean water is not a certainty for every human being. Today, there are major problems with polluted water that not just affect us humans, but also the ecosystem around us. In recent years, research into making aerogels from protein nanofibrils (PNF) has increased. What is interesting about these gels is their properties of adsorbing contaminants in the water, such as organic molecules and metal ions. In this report, hydrogels and non-dry aerogels (called “non-dry” due to there being one additional heat-treatment step that can be performed to “dry” the aerogel to make it sturdier and more water-proof), have been produced by whey protein isolate (WPI), which is extracted from the dairy industry. This is a sustainable, cheap, and renewable raw material. The goals are thus: (1) to examine if there is a difference in adsorption capacity between hydrogels and non-dry aerogels in a static setup and (2) to understand and examine which product parameters give the gels the best adsorption efficiency. To achieve these goals, eight different gels were synthesized with eight different contents. The parameters have varied from the following; dialyzed or non-dialyzed WPI solution, straight or curly seeds and whether or not salt had been added to the gels. The samples’ adsorption efficiency was analyzed by micro equilibrium dialysis (MED) and UV-VIS spectroscopy. For hydrogels, the dialyzed solution with salt and curly seeds was the variant with the highest binding capacity for ThT at 34% of the initial ThT concentration. For non-dry aerogels the dialyzed solution with curly seeds and no added salt was the best variant for binding ThT, at 84% of initial ThT content bound. It was also seen that the gels that have non-dialyzed WPI solution or that the solutions contained salt increased the adsorption capacity. The conclusions drawn were that salt has a positive effect on the adsorption capacity of the gels that have formed a matrix, and a negative effect on the adsorption of loose fibrils as well as that the solutions may not need to be dialyzed. The type of seeds or fibrils effect on adsorption capacity was inconclusive. The adsorption capacity for non-dry aerogels was three times higher compared to hydrogels. / Att ha tillgång till rent vatten är inte en självklarhet för varje människa. Idag är det stora problem med förorenat vatten som inte bara påverkar oss människor utan också ekosystemet. På senare år har forskning inom att tillverka aerogeler av protein nanofibriller (PNF) ökat. Det som är intressant med dessa geler är deras egenskaper att adsorbera föroreningar i vattnet, som till exempel organiska molekyler och metalljoner. I detta arbete har icke-torra aerogels (kallas "icke-torra" på grund av att det finns ytterligare ett värmebehandlingssteg som kan utföras för att "torka" aerogelen för att göra dem robustare och mer vattentålig) och hydrogels producerats av vassleproteinisolat WPI, som utvinns från mjölkindustrin. Detta protein är ett hållbart, billigt och förnybart råmaterial. Målet med denna rapport är att (1) undersöka om det finns skillnader i adsorptionskapaciteterna mellan hydrogels och icke-torra aerogels i ett statiskt medium (2) förstå och undersöka vilka produktionsparametrar som ger den bästa adsorptionskapaciteten. För att uppnå dessa mål har åtta olika geler syntetiserats med åtta olika innehåll. De varierande parametrarna var följande; dialyserad eller icke dialyserad WPI-lösning, raka eller krulliga frön och om salt har tillsatts eller inte. Proverna analyserades med mikro-jämvikts-dialys och UV-VIS spektroskopi. För hydrogeler var den dialyserade lösningen med salt och krulliga seeds den variant som hade högst bindningskapacitet för ThT, vilket låg på 34 % av den orginellaThT-koncentrationen. För icke-tora aerogels var lösningen som var dialyserad med krulliga frön och inget tillsatt salt den variant som var bäst på att binda ThT, med en kapacitet på 84% av den orginella koncentrationen. Vi såg även att gelerna som hade odialyserad WPI-lösning alternativt att lösningarna som innehöll salt ökade adsorptionskapaciteten. Slutsatserna som dragits är att salt har en positiv påverkan på gelernas adsorptionsförmåga när de format en fibermatris och en negativ påverkan när de bara består av fria fibriller, samt att lösningarna kanske inte behöver dialyseras. Typ av frön eller fibrillers påverkan på adsorptionsförmåga kunde inte påvisas. Icke-torra aerogels hade en adsorptionsförmåga på ThT som är tre gånger högre jämfört med hydrogels.

Crispness is one of the most desirable textural characteristics of breaded fried foods. Consumers often judge the quality of breaded fried foods based on the perceived crispness of the product. Furthermore, today's consumers are showing increasing concern over fat intake. As a result, there is great interest in being able to enhance the crispness and reduce the fat uptake in breaded fried foods without sacrificing other quality attributes. To achieve these goals, modifications to both frying equipment and product formulation have been explored in this study. In this study, two edible film coatings, methylcellulose (MC) and whey protein isolate (WPI) were incorporated into the batter and pre-dust to determine their effect on the crispness of breaded fried chicken nuggets held under a heat lamp for varying time intervals. Crispness was evaluated by both objective (ultrasonic non-destructive evaluation system) and subjective methods. An untrained sensory panel was used to obtain subjective measurements of product crispness. Panelists rated product attributes such as crispness, juiciness, oiliness and flavor on a simple intensity scale. Additionally, panelists rated the liking of the products on a nine-point hedonic scale (1=dislike extremely, 9=like extremely). Two pressure sources (nitrogen gas and steam naturally released from the food material) were used to determine their effects on product crispness, texture, pressed juice, moisture content, fat content and color. Products fried with nitrogen gas as the pressurizing medium produced samples that were comparable to or exceeding the quality of products generated by frying with steam, as it relates to product crispness, texture, pressed juice, moisture content, fat content and color. As related to objective crispness, chicken nuggets fried with nitrogen were significantly crispier (p<0.05) than those fried with steam. Coating type and application also had a significant effect on product crispness. Samples coated with MC in the pre-dust were crispier than samples coated with WPI. However, no significant differences were found in product crispness, juiciness, oiliness or flavor, and overall liking among samples tested by the sensory panel. The results of this study demonstrated that applying an edible film coating to the pre-dust and using nitrogen gas as the pressurizing medium can enhance and maintain the crispness of breaded fried foods. / Master of Science

Yes / We compared cetylpyridinium chloride (CPC), ethanol (ETOH), and OMNIgene.SPUTUM (OMNI) for 28-day storage of sputum at ambient temperature before molecular tuberculosis diagnostics. Three sputum samples were collected from each of 133 smear-positive tuberculosis (TB) patients (399 sputum samples). Each patient's sputum was stored with either CPC, ETOH, or OMNI for 28 days at ambient temperature, with subsequent rpoB amplification targeting a short fragment (81 bp, GeneXpert MTB/RIF [Xpert]) or a long fragment (1,764 bp, in-house nested PCR). For 36 patients, Xpert was also performed at baseline on all 108 fresh sputum samples. After the 28-day storage (D28), Xpert positivity did not significantly differ between storage methods. In contrast, higher positivity for rpoB nested PCR was obtained with OMNI (n = 125, 94%) than with ETOH (n = 114, 85.7%; P = 0.001). Smears with scanty acid-fast bacilli (AFB) had lower rpoB PCR positivity with ETOH storage (n = 10, 41.7%) than with CPC (n = 16, 66.7%; difference, 25%; 95% confidence interval [CI], 3.5 to 46.5; P = 0.031) or OMNI (n = 16, 69.6%; difference, 26.1%; 95% CI, 3.8 to 48.4; P = 0.031), with no difference between CPC and OMNI. Poststorage, the threshold cycle (CT ) values significantly decreased compared to those prestorage with ETOH (difference, -1.1; 95% CI, -1.6 to -0.6; P = 0.0001) but not with CPC (P = 0.915) or OMNI (P = 0.33). For one patient's ETOH- and CPC-stored specimens with a CT of <10, Xpert gave results of rifampin false resistant at D28, which was resolved by repeating Xpert on a 1/100 diluted specimen. In conclusion, 28-day storage of sputum in OMNI, CPC, or ETOH at ambient temperature does not impact short-fragment PCR (Xpert), including for low smear grades. However, for long-fragment PCR, ETOH yielded a lower PCR positivity for low smear grades, while the performance of OMNI and CPC was excellent for all smear grades. (The study has been registered at ClinicalTrials.gov under registration number NCT02744469.). / Directorate General for Development (DGD), Belgium (FA4 to C.N.S., B.C.D.J., D.A., and L.R.), and the European Research Council-INTERRUPTB starting grant (number 311725 to B.C.D.J., C.J.M., and L.R.)

Des solutions d'isolat de protéine de lactosérum (WPI) et d'isolat de protéine de soja (SPI) ont été chauffées à différentes concentrations en protéines conduisant à la formation d'agrégats fractals polydisperses de taille moyenne variable. Lastructure des solutions a été analysée par diffusion de la lumière en fonction de la concentration en protéine. La compressibilité osmotique et la longueur de corrélation dynamique diminuent quand la concentration augmente deviennent indépendantes de la taille initiale des agrégats pour les suspensions denses. Pour une taille d'agrégat donnée, la viscosité augmente initialement exponentiellement avec la concentration croissante puis diverge. Plus lesagrégats sont grands, plus l’augmentation de la viscosité apparaît à des concentrations faibles. La dépendance avec la concentration de la viscosité des solutions d'agrégats fractals est beaucoup plus forte que celle de microgels. Le comportement de mélanges de différents types d’agrégats (fractals/fractals ; fractals/microgels et WPI/SPI) a étéétudié principalement par rhéologie.Le recouvrement de fluorescence après photoblanchiment (FRAP) a été utilisé pour étudier la diffusion de chaînes de dextran marquées par des fluorophores dans des solutions d’agrégats et des gels de WPI. Une diffusion brownienne estobservée dans des suspensions d’agrégats et des gels faibles formés juste au-delà de Cg avec un coefficient de diffusion (D) qui diminue avec l'augmentation de la concentration mais, avec une dépendance plus faible que celle de la viscosité (). A des concentrations plus élevées, des gels densément réticulés sont formés, ce qui induit une forte diminution de la mobilité des chaînes de dextran. Pour ces systèmes, la recouvrance de la fluorescence est logarithmique avec le temps,suggérant une distribution exponentielle des coefficients de diffusion. La diffusion des chaînes de dextran a également été étudiée en fonction de la concentration en protéines pour les suspensions de trois types d'agrégats de WPI (petits et grands fractals et microgels). / Polydisperse fractal aggregates of varying average sizes were formed when solutions of whey protein isolate and soy protein isolate were heated at different protein concentrations and at neutral pH. The structure of these fractals aggregates solutions was analyzed by light scattering as a function of protein concentration. In dense suspension, the osmotic compressibility and the correlation length decreases with increasing concentration and become independent of the initial aggregate size. In this concentration regime, the aggregates are strongly interpenetrated and can be visualized as a set of "blobs". For a fixed aggregate size, the viscosity initially increases exponentially with increasing concentration and then diverges at the gel point. Larger fractal aggregates show a more important increase of the viscosity with increasing concentration than smaller aggregates, because they are less dense. The increase of the viscosity was much stronger for large fractal aggregates than for homogeneous microgels (microgels were formed by heating the WPI solution in present of CaCl2) of the same size.Dynamic light scattering, rheology and FRAP measurements were performed to investigate mixtures of different type of aggregates of WPI (fractals/fractals, fractals/microgels) and fractals of mixtures of WPI and SPI. Flow measurements were used to characterise the rheological properties of the aggregate suspension whereas Fluorescence recovery after Photobleaching (FRAP) was used to determine the self diffusion of fluorophore-labelled dextrans chains in mixtures over a wide range of concentrations. The results were compared to the concentration dependence of zero shear viscosity, gel stiffness, osmotic compressibility and correlation length. Brownian diffusion of the dextran chains was observed in aggregate suspensions and weak gels formed just above the gel point with a diffusion coefficient that decreased with increasing concentration, but the dependence was weaker than that of the viscosity. At higher concentrations, densely crosslinked gels were formed, which induced a sharp decrease in the mobility of the dextran chains. For these systems, the recovery of fluorescence was logarithmic over time, suggesting an exponential distribution of diffusion coefficients.

Under flera månaders tid har ett kandidatexamensarbete utförts med syftet att optimera produktionen av protein-nanofibrer av vassleproteinisolat. Vassleproteinisolat består till stor del av proteinet β-laktoglobulin. Detta protein kan under upphettning bilda nanofibrer i sur miljö. Det var därför med avseende på parametrarna värme, koncentration och inkubationstid som processen optimerades eftersom det redan existerar ett pH-optimum vid pH-värdet 2. Lösningar av vassleproteinisolat med olika koncentrationer inkuberades under 24 timmar vid fyra olika temperaturer. Samtliga lösningar hade pH-värdet 2. För varje temperatur och inkubering togs proverna ut en åt gången för att sedan analyseras. De olika proverna analyserades sedan med Thioflavin T fluorescens för att se indikationer på fibrillering. De erhållna ThT spektrumen visade på fibrillbildning och resultaten för detta experiment visar på att utbytet av fibrilleringsreaktionen blir högre i takt med att hydrolysens hastighetskonstant blir lägre samt att lägre temperaturer kan gynna fibrillbildning . Ytterligare försök, tid och resurser bör läggas ner på detta område för att med säkerhet kunna optimera produktionen av nanofibrer av vassleproteinisolat. / This bachelor’s degree project’s aim was to optimize the production of protein nanofibrils originating from whey protein isolate. Whey protein isolate largely consists of the protein β-lactoglobulin, which can form nanofibrils while immersed in an acidic environment when heated. Therefore, the process was attempted to be optimized with regards to the yield of the final product of protein nanofibrils by varying parameters such as incubation time, initial concentration and temperature, with a constant pH-value of 2. Solutions of the whey protein isolate at different concentrations were incubated during a time interval of 24 hours and at different temperatures. For every temperature and time period of incubation, one sample at a time was taken out to be measured and analyzed, a total of four samples per initial concentration. The samples were analyzed with Thioflavin T fluorescence to see indications of the existence of fibrillation. The obtained ThT spectra showed intensity diagrams that can be related to the amount of formed nanofibrils, and this experiment shows that the yield of fibrils increases while the rate constant of the hydrolysis decreases, and that the fibrillation is favoured by lower temperatures. To optimize the production of nanofibrils of whey protein with certainty, further experiments, time and resources should be invested in this area.

Introdução - A soja e outras leguminosas são consideradas como alimentos funcionais por apresentarem propriedades hipocolesterlemizantes. Esta propriedade, porém, ainda não foi relatada para o feijão caupi. Um possível componente deste grão responsável pelo feito redutor de colesterol é sua proteína. Objetivo - Produzir isolado protéico de feijão caupi e verificar a influência do grão integral e de sua proteína isolada no metabolismo lipídico de hamsters hipercolesterolemizados pela dieta. Métodos - O isolado protéico de feijão caupi foi produzido por precipitação isoelétrica, utilizando-se pH 8,5 para solubilização da proteína e 4,5 para a sua precipitação, obtendo-se um isolado com 92 % de proteína. O isolado protéico (IP) e o feijão caupi integral (FCI) foram utilizados como fonte protéica em dietas experimentais para hamsters que tiveram hipercolesterolemia induzida por dieta contendo 20 % de caseína, 13,5 % de gordura saturada e 0,1 % de colesterol, por 3 semanas. Os animais foram distribuídos em três grupos, recebendo cada grupo dieta com 20 % de caseína (controle), dieta com 20 % de proteína de isolado de feijão caupi e dieta com 20% de proteína de feijão caupi integral, por 4 semanas. Resultados - Comparando-se à dieta controle, a dieta com FCI e IP provocaram reduções significativas no colesterol total (49 % e 20 %, respectivamente) e colesterol não-HDL (54 % e 22 %, respectivamente). Análises histológicas do fígado foram realizadas e observou-se que IP e o FCI proporcionaram efeito hepatoprotetor comparado à caseína, pois o grupo que recebeu caseína apresentou em média esteatose difusa e intensa, enquanto grupo com feijão e isolado apresentaram esteatose focal e, em alguns casos, ausentes. Alguns possíveis mecanismos envolvidos para o efeito benéfico no metabolismo lipídico foram investigados. A digestibilidade verdadeira do IP foi igual à da caseína, enquanto a do feijão integral foi menor. A excreção de ácidos biliares e colesterol foi inversamente proporcional aos níveis plasmáticos do colesterol dos animais submetidos às diferentes dietas. Os animais com a dieta de feijão integral apresentaram a maior excreção de ácidos biliares e colesterol nas fezes; valores estatisticamente diferentes aos dos animais da dieta com caseína. Conclusões - O feijão caupi e sua proteína isolada reduzem o colesterol plasmático e proporcionam efeito hepatoprotetor. A digestibilidade, excreção de ácidos biliares e colesterol não estão relacionados com a redução do colesterol provocada pelo IP. O mecanismo envolvido na redução do colesterol nestes experimentos ainda não está totalmente elucidado, sugerindo que a proteína isolada do feijão caupi atue na síntese de colesterol, pois não foi observado aumento na sua excreção. / Introduction - Soya and other legume seeds are considered functional food because of their hypocholesterolemic properties. This property, however, is not reported yet for cowpea. A possible component present in this grain that could respond for the hypocholesterolemic effect is the protein fraction. Objective - To produce protein isolate of cowpea and to verify the influence of the whole seed and its isolated protein on the lipid metabolism of diet hypercholesterolemized hamsters. Methods - The cowpea protein isolate was prepared by isoelectric precipitation, using pH 8.5 for solubilization and pH 4.5 for protein precipitation. The isolate obtained presented protein content of about 92%. The protein isolate (PI) and cowpea whole seed (CWS) were used as protein source in experimental diets fed to hamsters that previously had their blood cholesterol increased by a diet containing 20 % of casein, 13,5 % of saturated fat and 0,1 % of cholesterol during 3 weeks. Animals were divided into 3 groups and fed on diets containing: 20 % casein (control), 20 % isolate protein of cowpea and 20 % of cowpea whole seed for 4 wks. Results - The results showed that for hamster that fed on diets containing PI and CWS occurred a significant decrease in total cholesterol (49 % and 20 %, respectively) and non-HDL cholesterol (54 % and 22 %, respectively), as compared to casein group. Histological analysis of hepatic tissue was performed and showed that PI and CWS presented reduction in hepatic lipotoxicity as compared to the casein group. Therefore, the group that received casein presented steatosis widely distributed throughout the hepatic lobule, while whole seed cowpea and protein isolate meal groups produced only focal steatosis and, in some cases, it was absent. Some mechanisms involved in lowering plasma cholesterol were investigated. Digestibility for PI was equal for casein group, while it was significantly lower for CWS group. The bile acids and cholesterol excretion in the feces were inversely proportional to plasma cholesterol levels. Animals on CWS presented higher levels of feces bile acids and cholesterol; these values were statistically different from animals on casein diet. Conclusions - Whole seed cowpea and its protein isolate reduce plasma cholesterol and hepatic lipotoxicity. Digestibility, the bile acids and cholesterol excretion are not related to hypocholesterolemic effect of protein isolate of cowpea. The mechanisms involved cholesterol reduction in these experiments is not yet fully elucidated. It is suggested that protein isolate of cowpea is related to the cholesterol syntheses, as it was not verified any increase in cholesterol excretion in the animals on protein isolate diet.

Endogamy levels are usually estimated using genealogical or molecular markers data. By means of both type of data from a traditional Brazilian tri-hybrid quilombo population aggregate (located at the Ribeira River Valley in the State of São Paulo), the aim of this work, using different methods, was to obtain reliable estimates of its average inbreeding coefficient, as well as to establish pertinent demographic inferences. The results we obtained are presented in three chapters. The first one, represented by the offprint of a published paper, deals with the estimation of the inbreeding coefficient using both a complete genealogical and comprehensive molecular information. F values were estimated for each community using all available pedigree information and averaging the inbreeding coefficients from all individuals represented in the genealogies. Molecular f values were estimated from the analysis of 30 highly heterogenous sets of molecular markers (14 biallelic SNPs and 16 multiallelic microsatellites), genotyped in different groups of individuals from the population. The second chapter (a research paper already published), presents a simplified method to estimate the variance of the inbreeding coefficient. The simple approximations we provided can be applied to a locus with any number of alleles, producing estimates fully validated by computer simulations. The last chapter is a manuscript yet to be published that deals with inbreeding and demographic inferences, obtained from the information of hundreds of thousands of biallelic SNP markers. A new manner to obtain estimates of Wright\'s fixation index f is presented, consisting in the use of the joint information of two sets of markers (one complete and another excluding markers in patent linkage disequilibrium). Quilombo demographic inferences were obtained by means of ROHs analyses, which were adapted to cope with a highly admixed population with a complex foundation history / Os níveis de endogamia de uma população são comumente estimados por meio do coeficiente de endocruzamento, que pode ser obtido de dados genealógicos (F) ou dados provenientes da análise de marcadores moleculares (f). O objetivo do trabalho foi obter estimativas confiáveis do coeficiente de endocruzamento populacional, bem como realizar inferências demográficas, usando dados de um agregado populacional quilombola miscigenado com ancestralidade complexa tri-híbrida, localizado no Vale do Rio Ribeira, na região sul do estado de São Paulo. No trabalho é apresentado em três capítulos. No primeiro (um trabalho já publicado), estimamos o coeficiente de endocruzamento usando dados genealógicos e moleculares. As estimativas genealógicas de F foram obtidas para cada comunidade por meio da média dos coeficientes individuais de todos os indivíduos representados nas genealogias da população. Os valores de f foram estimados por meio dos dados de 30 marcadores moleculares altamente heterogêneos (14 SNPs e 16 microssatélites), genotipados em diferentes grupos de indivíduos com diferentes finalidades. O segundo capítulo, representado por um trabalho também já publicado, apresenta um método simples para estimar a variância do coeficiente de endocruzamento f. As aproximações obtidas, validadas devidamente por simulações em computador, podem ser aplicadas a lóci multialélicos, produzindo estimativas que não diferem significativamente de outras aproximações complicadas descritas na literatura. O último capítulo (um manuscrito a ser submetido para publicação) apresenta inferências a respeito dos processos de endogamia e demografia no isolado quilombola, utilizando a informação de centenas de milhares de marcadores moleculares bialélicos. É apresentada uma nova maneira de se estimar o índice de fixação f de Wright, usando a informação combinada de dois conjuntos de marcadores (o conjunto completo de marcadores e um outro contendo apenas marcadores não ligados significativamente entre si). Também foram feitas inferências sobre a história demográfica do isolado por meio do estudo das regiões genômicas em homozigose (ROHs), uma contribuição inédita e importante do trabalho, adaptada à análise de um isolado populacional altamente miscigenado com contribuição tri-híbrida e uma história de fundação complexa