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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Separace vybraných frakcí kyselých proteinů z hlíz brambor (Solanum tuberosum L.) pomocí chromatografických technik / Separation of selected acidic proteins fractions from potato (Solanum tuberosum L.) tubers by chromatographic techniques

LORENC, František January 2013 (has links)
This diploma thesis deals with acidic proteins contained in the potato (Solanum tuberosum) tubers, or rather about their separation with chromatography techniques. For the analysis were chosen tubers of two czech potato varieties, Adéla and Westamyl. From the concentrated potato juice were eliminated basic and most of the patatin proteins with the gravity column chromatography. In the next step were applied the chromatography techniques on the anion and hydroxyapatite columns by the fast protein liquid chromatography (FPLC) system. On the anion column were separated protein fractions which contained proteins of molecular weight in the range of 15 kDa to 60 kDa (Adéla) and 15 kDa to 100 kDa (Westamyl). The most abundant were the proteins with molecular weight 15 kDa a 20 kDa. In the last step was used the mass spectrometry for the identification of chosen protein fractions.
42

Zavedení metody stanovení konjugované linolové kyseliny (CLA) / Introduction of the method for assessment of conjugated linoleic acid (CLA)

Ruprichová, Lenka January 2009 (has links)
This work deals with the optimization of the method for determination of conjugated linoleic acid (CLA) using gas chromatography. The summary about formation and occurrence of CLA in animal materials, its biological effects in human organism and methods suitable for its determination is introduced in the theoretical part of this study. The experimental part verify, if the gas chromatography is applicable method for assesment of CLA in selected biological matrices. The chosen method was introduced and verified at FCH of Brno university of technology. At the end the applicability of this method to CLA determination is discussed here.
43

Stanovení pepsinogenů za použití IgY a IgG / Determination of pepsinogens using IgY and IgG

Kulhavá, Lucie January 2014 (has links)
A decreased concentration of pepsinogen A in serum was found to be a marker of gastric cancer, similarly as a low ratio of pepsinogen A to pepsinogen C. In the present study we have compared properties of immunoglobulin fraction isolated from the egg yolks after immunization of laying hens with pepsinogen isolated from porcine gastric mucosa with those of present in rabbit antiserum obtained after the animal immunization with the same antigen. The characteristics of chicken antibodies against porcine pepsinogen and the comparison with rabbit antibodies raised against the same antigen was carried out using the following methods: ELISA, affinity chromatography on immobilzed antigen and bovine serum albumin, SDS and native electrophoresis and MALDI-TOF MS/MS. While the rabbit specific antibodies interacted with the used antigen and only slightly with bovine serum albumin and there was a diference between pre-immune IgG and specific IgG, in the case of chicken antibodies IgY it did not work. No diference was observed between ELISA tests performed with pre-immune serum and the serum after immunization with porcine pepsinogen and a high interaction of IgY with bovine serum albumin in pre-immune serum and specific IgY after the immunization were detected. Similar results were obtained in experiments with...
44

Stanovení neesterifikovaných mastných kyselin v krevní plasmě / Determination of non-esterified fatty acids in plasma

Lacinová, Petra January 2014 (has links)
The determination of non-esterified fatty acids (NEFA) in plasma is possible by many routine biochemical methods. For more detailed metabolic studies it is required to analyse the fatty acid (FA) profile. The NEFA profile determination is usually performed by the capillary gas chromatography (GC), but the sample preparation is not uniform. NEFA may be isolated by the extraction process or by the preparative thin-layer chromatography (TLC). The aim of this study was to compare these two separation procedures. The samples of pooled plasma from volunteer donors were analyzed by capillary GC after previous separation procedure by the TLC and the liquid-liquid extraction. The results were compared by the t-test for both the absolute concentration of individual FA provided by the internal standard (margaric acid) method and the relative abundance (Rel%). The reproducibility of the results was significantly better for the liquid-liquid extraction method than the TLC. The relative standard deviations (RSD) of the FA groups (unsaturated, monosaturated and polysaturated) were from 4.3 to 11.3 % vs. 8.6 to 33.8 % for the relative abundance and from 16.5 to 25.5% vs. 15.4 to 47.4% for the absolute concentration. For each FA, which were represented by more than 0.1 Rel %, RSD ranged from 4.5 to 47.8% vs. 9.5 to...
45

Studium složení palmového oleje z hlediska autenticity

Heinz, Petr January 2018 (has links)
The palm oil is the most desirable raw material in a wide range of industry in the 21st century. It is a basic material for food, cosmetics, biodiesel and many other products. However, it’s production has a negative impact on the environment. In this thesis the palm oil authenticity is judged according to the differences in composition depending on the conditions of cultivation, which is related to the certification of this raw material. The fatty acid spectrum in the samples of palm oil was determined by method of gas chromatography coupled with flame ionization detection. In terms of total fatty acids content, the non-certified palm oil (fat sample 1) containing 0.969 g.g-1 fat (after three months storage 0.880 g.g-1 fat) is better than certified palm oil (fat sample 2) containing 0.648 g.g-1 fat (after three months storage 0.533 g.g-1 fat).
46

Screening biologicky aktivních látek v pivu

Hložek, Marek January 2018 (has links)
The thesis focuses on beer components with health benefits and methods of determination of these substances. The theoretical part is divided into 5 chapters in which the brewing process is described including the necessary raw materials, the issue of biologically active substances and the methods of their determination are here also outlined. In the last part there are also briefly mentioned volatile substances found in beer. The aim of the experimental part was to determine organic acids, phenolic compounds and 5-MTA in the chosen samples of Czech and German lagers. For the analysis, 5 samples from each country were used. To the analysis was also used beer brewed in the premises of Mendel University in Brno. In this beer were determined the changes in the content of selected substances in 6 stages of the brewing process and in the final product. Beer is a complex matrix, requiring a solid phase extraction (SPE) treatment prior to HPLC analysis.
47

Vliv přídavku vybraných olejů na depozici mastných kyselin ve tkáních pokusných živočichů

Vymazalová, Pavla January 2018 (has links)
The thesis contains a theoretical overview, which has focused on classification of lipids, fatty acids and their metabolisms, with emphasis on polyunsaturated fatty acids inclusive of their conversion to eicosanoids, functions and effects of eicosanoids on human health. Furthermore, the theoretical part of the thesis has focused on a food’s enrichment of polysaturated fatty acids n-3 and several possibilities of analytical determination of fatty acids. The practical part of the thesis has aimed attention at the determination of fatty acids in the liver, fat and muscles’ tissue of the experimental rats. The animals were fed with a standard feed mixture, which contains 5 % of fish oil, 5 % of palm oil, 5 % of safflower oil and 5 % of Schizochytrium algae extract. The obtained fat was extracted from the lyophilized samples followed by derivatization and analytical determination of the fatty acid derivatives by gas chromatography. From the results of the experimental part could be determined, that the addition of 5 % of fish oil to the feed mixture of the experimental animals increased the deposition of EPA and DHA in all examined tissues (p < 0.05). The addition of 5 % of the Schizochytrium extract to the animal’s feed mixture had an impact on the effective deposition of DHA and DTA in the examined tissues of all used oils (p < 0.05). Both of the previously mentioned oils can be considered as the most effective nutraceuticals for reducing the ratio of PUFA n-6/n-3 in the food. Unlike the addition of 5 % of safflower or 5 % of palm oil (as a control), ratios of PUFA n-6/n-3 were many times higher. Therefore, from the healthy point of view, this can be concluded as inappropriate.
48

Depozice dietárních mastných kyselin ve vybraných vnitřních orgánech a tkáních pokusných živočichů

Štumarová, Klára January 2019 (has links)
This diploma thesis deals with the issue of fatty acids containing distribution, metabolism, physiological properties and effects on health. In the experimental part there is detail descripiton of the experiment, where the amount of dietary fatty acids in the liver and visceral fat in rats was determined. Rats were divided into five groups, each of that was fed with mixture with 8% oil addition (palm oil, fish oil, safflower oil and Schizochytrium extract). The last group was fed with the mixture without any oil addition. The results of the experiment point to a high SFA content in feed with 8% fish oil addition. Although fish oil contains a significant amount of n-3 PUFA, high deposition of SFA could have negative effects on plasma lipid and lipoprotein levels. The most suitable oil is Schizochytrium microalga extract, which has a positive effect on EPA and DHA deposition, but does not contain significant amount of SFA, MUFA and PUFA n 6. Regarding the ratio of PUFA n-6/n-3, fish oil appears to be the second most suitable. The least suitable PUFA n-6/n-3 ratio is observed in safflower and palm oil.
49

Variabilita obsahu a složení silic u vybraných druhů koření (Ocimum basillicum L., Satureja hortensis L. a Majorana hortensis Moench.)

Benešová, Jana January 2017 (has links)
The thesis Variability and composition of essential oil content of selected spices (Oci-mum basillicum L., Satureja hortensis L. and Majorana hortensis Moench.) Deals with plant species of whose main ingredient is oil. There is described a process for the isola-tion of essential oils from plants, individual components of essential oils, their variability and ways of using. Selected representatives of the so called green spices belong to the mint family (Lamiaceae), whose typical feature is very high content of essential oils. In the practical part were evaluated following species: basil (Ocimum basilicum), sum-mer savory (Satureja hortensis L.) and marjoram (Origanum majorana syn. Majorana hortensis). Essential oil content was determined in each type, by steam distillation and then the composition of essential oils was found by gas chromatography.
50

Sorpce PCP na lignitu / PCP sorption of lignite

Šnédarová, Gabriela January 2008 (has links)
Within the framework of this diploma thesis, the sorptive capability of a lignite as a natural adsorbent was applied on an aqueous solution of pentachlorophenol. The aqueous solution of this substance, which is very dangerous for the environment, was prepared in various concentration ranges according to reached solubility. The solubility is noticed in different literatures variously and then is not applicable. That is why it was necessary to find out the ”real“ solubility. The aqueous solution of pentachlorophenol of given concentration was subsequently put to adsorption with exactly defined quantity of the lignite and as a result the adsorptive isotherms were obtained. These isotherms represent the adsorption capability in dependence on the adsorption duration, quantity of used lignite and concentration of pentachlorophenol solution. By the adsorption with duration longer than one hour, the quantity of adsorbed PCP does not increase markedly.

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