Casein proteins are important escpecially for cheese making. In addition to technology and other factors, casein concentration in milk and relative representation of individual casein fractions influence cheese yield. Majority fractions are alfa-casein, beta-casein and kappa-casein. For the determination of proteins in the milk can be used electrophoretic techniques or near infra-red spektrometry. High performance liquid chromatography (HPLC) is going to be used. HPLC is widely used analytical method, which is based on differential affinity of the substances to the mobile and the stationary phase. The thesis has introduced the method of determining the casein fractions by HPLC. The method was partially optimized using cow milk and calibrated to the standard solutions, which were purchased casein fractions derived from the bovine milk. Real samples of cow, sheep and goat milk were analyzed. The goat milk was available in several variants: Sanski goat milk and white shorthair goat from domestic or farm breeding. All milk samples were analyzed for casein and casein fractions proportions. Chromatograms show that the casein formula is different in cow, sheep and goat milk. Different concentrations of the casein fraction in the milk of various animal species have been statistically detected in almost all cases. The exception was the concentration of beta-casein in the milk of white shorthair goat from the domestic and the farm breeding and cow milk. In these types of milk there was no statistically significant difference in the concentration of beta-casein. Analysis of individual samples of white shorthair goat milk from the farm breeding shown that casein content in the milk of different animals reared under the same conditions may be different. Ratios of beta-casein to alfa-casein, beta-casein to kappa-casein and alfa-casein to kappa-casein were evaluated in all samples. Interspecific comparisons proved that ratios were statistically significantly different in all milks. In the milk of Sanski goat, there was found the stable ratio of beta-casein to alfa-casein during lactation. For all goat milk there were typical higher values of the ratio of beta-casein to kappa-casein. The ratio of alfa-casein to kappa-casein was highest in the sheep milk. Despite some shortcomings, it is possible to use the HPLC method possible for these purposes, but it is necessary to continue with its optimization.

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In this graduation thesis, I have investigated the influence of the season on market production dairies. he aim of the work is divided into the following sub-goals: the influence of season on the reception of milk to the dairy, protein content in milk, yield milk and ferment aktivity. The dairy, which I described handles mainly on cow's milk for cheese Niva, curd and cream. Milk came from 8 surrounding farms, which breeding only the Czech Pied cattle. Monitoring was carried out for a period of one year starting from November 2014 to October 2015. I found that most milk was bought from suppliers in summer and least in the winter months. The milk protein content was highest in winter and lowest in summer. While the amount of milk purchased was constant, the price per liter of milk has a tendency of decreasing (from CZK 9.05 to 7.48), and thus the costs of buying milk lower, while revenues are constant. Milk yield ranged from 7.43 liters of milk / kg of cheese (in October) to 8.42 l / kg cheese (in February).

The aim of the thesis was to prove the effect of Lignohumate B and Synergin bio-stimulators and their combined effect on the cultivation of strawberries in simulated organic production. The preparations were expected to influence growth, health, yield and quality of the fruit. 'Honeoye' and 'Symphony' varieties were selected for the proving also in order to test their suitability for this type of cultivation in the specific conditions of the Czech Republic. Experiments were set up and assessed on experimental plots at the Faculty of Horticulture in Lednice, taking place between 2007 and 2009. No statistic proving of positive effect of the tested preparations - Synergin, Lignohumate B and their combined application was found in terms of growth characteristics, yield and qualitative parameters of strawberries. The results suggest that application of Synergin (protein hydrolysate) and Lignohumate B (lignosulphonate) on strawberries is not justified. The most important variety for setting up organic strawberry plantations is the one that is resistant to more diseases and has a high yield potential at the same time. These requirements were met only by the 'Symphony' variety.

This diploma thesis deals with fractionation of protein from hemp (Cannabis sativa L.) meal according to their solubility of the hemp varieties - Fedora 17 and Uso 31. The content of nitrogenous substances and protein content in the hemp meal of these studied varieties ranged from 23,6 % (Uso 31) to 31,5 % (Fedora 17) and from 100,1 mg.g-1 (Uso 31) to 130,7 mg.g-1 respectively. The fractionation of hemp protein (Fedora 17, Uso 31) confirmed that the main hemp protein fraction is an albumin fraction, with its relative abundance - 20,5 % of protein. As a next step, the spectra of hemp proteins were determined. The use SDS-PAGE analysis revealed albumin proteins in area of 7,4 53,6 kDa. In the globulin fraction was revealed by SDS-PAGE basic subunits of the major protein edestin in the area 19-21 kDa and acidic subunits in the area 34 kDa.

An experimental study on randomly generated protein sequences can provide important insights into the origin and mechanism of secondary structure formation and protein folding. In this study we bring biophysical characterization of five protein sequences selected from the in silico generated library of random chains. The sequences were selected on the basis of bioinformatic analysis in order to find the candidates with the maximum potential to possess secondary structure. This study shows that the random polypeptide sequences form stable secondary structures and in some show the signs of tertiary structure, such as hydrophobic core formation and distinctive oligomerization pattern. While the work presented in this thesis is work in progress on a larger study, the data already demonstrate that unevolved protein sequence space provides a lot of potential for secondary and tertiary structure formation that awaits its characterization. Powered by TCPDF (www.tcpdf.org)

The goal of theoretical part of this my diploma thesis was to study and find out needs of human organism in all phases of life to amount of nutritions and energy income. Next goal was to describe contents of meat products and determinate benefits and negatives of their consummation. Next, the demands for content of meat products and their labeling was described. In practical part of my diploma thesis was determined contents of proteins, fats, salt and dry matter was determined. From the contents of proteins and fats was than calculated energy values of selected meat products. Proteins was determined by Kjeldahl´s method. Fats were determined with extraction method by Soxhlet and also by machine MeatScanTM. Contents of salt was determined with argentometric method by Mohr and dry matter was determined gravimetricly and on machine MeatScanTM. Final results were compared with tables of contents on packages of analyzed meat products. Differences between determined values and values which were on labels was found in approximately 75% cases (P < 0.05). Test results were then used for comparison of nutrient and energetic values between analyzed meat products. Best results from the nutrition point of view had “selection ham” and “the ham of highest quality”. Contents of nutritions was then compared with the valid legislative. All samples of meat products were in compliant with set demands. Lastly, there was sensor analysis. The products were divided in two groups. In one group, there were only franfurters. In the second group were remaining samples of meat products. With frankfurters the only proven difference was in the descript of salinity in spite of the fact, that the samples didn´t have different content of salt (P < 0.05). The best rated product in the second category was “the ham of the highest quality”, the worst rated product was “selected beef ham”. From the nutrient and a sensor point of view is best “the ham of highest quality”.

This Master thesis called Comparison of methods for measuring milk coagulation deals with a major technological step in the production of cheese, which is the process of curdling of milk. Two methods for measuring this process were compared, particularly the visual and instrumental method utilizing nephelo-turbidimeter. Based on statistical data processing in three cases, a difference was observered between the average visual measurement and instrumental measurement of significant 99%. Furthermore, the impacts on curdling of milk were assessed what showed that the best default property for the process of curdling had a pasteurized milk sample with the addition of CaCl2. On the basis of calculations in this thesis it has been concluded that to curdle a 100 l of milk with rennet CHY-MAX a 0,2 liters of the rennet is required. The same amount of milk is curdled with 1 litre of rennet Lactochym. In assessing the economics of using rennet Lactochym and CHY-MAX it has been found that for cost optimization it is more appropriate to use rennet CHY-MAX with a strentgh of at least 190 IMCU/ml diluted in distilled water at a ratio of 1:5.

Some proteins require presence of their specific ligand, cofactor or prosthetic group for their activity. Binding of this specific molecule can cause conformational changes which permit to perform their function. In some occasions the identification of conformational changes could be really challenging task. In this thesis we describe the novel approach for monitoring structural changes in proteins using chemical cross-linking and high resolution mass spectrometry and its application on model calmodulin system. It is demonstrated that analysis using isotope-labelled cross-linking agents enabled us to get insight into the structural rearrangement caused by presence or absence of the protein ligand. However, it is shown that the method has potential drawback due to limited enzymatic proteolysis. The novel approach that also makes it possible to quantify the changes in protein structure was used together with other methods for characterization of the neutral trehalase Nth1 in complex with Bmh1 protein (yeast isoform of protein 14-3-3). The results revealed that Bmh1 induce structural rearrangement of Nth1 molecule with changes within the EF- hand like motif which is essential for the activation process.

Title: Effect of protein (amino acid) ingestion on muscle protein synthesis following resistance exercise. Purpose: The main objective of this thesis is to verify the three basic factors of the amount, type and timing of protein intake based on scientific studies and literature, to provide the most objective and accurate information and procedure on the methodology of nutrition and supplementation associated with the intake of protein / amino acids after strength training and how it all affects muscle synthesis. Summery: The theoretical part of the thesis, discusses the factors affecting muscle protein synthesis, which stimulate growth and tissue regeneration, based on optimal stress response. Logically, it starts from general, i.e. the explanation of terms such as muscle tissue, the stimulation of muscle tissue and its manifestations and changes, nutrition factors and muscle stimulation, the mechanism of dietary factors (proteins/amino acids), specificity of protein/ amino acids in their application to answer the three key issues, which are summarized in the section named scientific studies, which focuses on the effect of intake of protein/ amino acids, in relationship to the efficiency of protein synthesis after strength training. The section summarizes, in detail, the questions of timing,...