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.

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).

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.

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.

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.

Comprehensive gas chromatography (GC×GC) is a modern and advanced analytical method designed to separate very complex samples, when the separation efficiency of classical gas chromatography is not sufficient. GC×GC allows complete simultaneous analysis of a sample on two different columns, interconnected by special interface called the modulator. Three types of control units were set up and a robust pulse flow modulator (PFM) was developed in this work. PFM working parameters have been always optimized to allow combinations of columns with different sizes. Optimized PFM allows application of columns with 10-60 m length and 0.15-0.25 mm internal diameters for the first dimensions and with 1-10 m length and 0.25-0.32 mm internal diameters for the second dimension. For demonstration reasons, analyses of complex real samples, such as essential oils, oil derivatives and biological samples, were performed. PFM was compared with the commercial cryofocusation modulator Zoex for the selected column set and one sample (a mixture of volatile solvents) on a gas chromatograph equipped with both modulators. The average repeatability of retention times, expressed as a relative standard deviation, was approximately 2.0 % for PFM (cryofocusation about 0.5 %) and of the peak areas was approximately 3.5 %...

The thesis is devoted to the utilisation of expansion turbines in the thermal power stations and in the industry companies using gas pressure reduction for technology purposes. The theoretic part of this thesis deals with the technology equipment such as steam and gas turbines, generators and reduction stations. The special attention is given to the expansion turbines with regard to its dividing in two groups: for steam reduction and for gas reduction. The parctical part includes the preliminary and detailed calculation of the expansion turbin for parameters of reduction line for combustion turbines, the generator proposal and the possibility of power extraction. The economic part completes the thesis with the economic evaluation of investment efficiency.

A method employing solid-liquid extraction with methanol and solid-phase extraction (SPE) clean-up step using Supelco SupelcleanTM ENVITM -Carb 3 mL cartridges (0.25 g graphitized carbon adsorbent) followed by gas chromatography - mass spectrometry with negative chemical ionization (GC-NCI-MS) has been optimized and applied for determination of ultratrace concentrations of C6 - C12 perfluorinated carboxylic acids (PFCAs) in soil samples. A sophisticated multifactorial statistic method, response surface methodology, employing 1/16 fractional factorial design and the face centered central composite design as well has been applied to find the significant parameters which influence the extraction procedure of PFCAs and SPE clean-up step and to set the optimum extraction and clean-up levels of eight parameters evaluated yielding the maximum extraction recovery of all PFCAs. The analyte extraction recoveries and the limits of detection and quantification have been obtained. The recoveries of individual PFCAs were within a range from 85 to 100 % for analyte spiked concentration level of 1.1 ng g−1 and within a range from 91 to 107 % for analyte spiked level of 2.1 ng g−1 . The values of limits of detection were 1.9 - 3.0 pg g−1 and limits of quantification 6.4 - 10.1 pg g−1 . This analytical method has...

The simplification of the historical pieces of work samples' treatment is described in the dissertation. The recent methods have been inappropriate therefore, modification of the treatment was necessary. The dammar and copal resin, important restoration materials, were used in the experiment. HPLC-MS, HPLC-ELSD, GC-FID, GC-MS and pyrolysis GC- MS were applied. The concentration of fatty acids in the historical sculpture was determined by GC-MS, and it was compared to the content of fatty acids inside an egg. For identification of monosaccharide in the gum, GC-MS (hexamethyldisilazan, trimethylchlorsilan, and pyridine) is the suitable method. GC-MS determines the same composition of dammar resin as stated in the cited sources. The simple process for the samples' treatment was designed.

Endocrine disruptors represent a group of chemical compounds that are able to negatively influence the hormonal system of vertebrates. Environmental Protection Agency (U.S.EPA) defines these compounds as exogenous substance or mixture that interferes with the synthesis, secretion, transport, binding, activity, or degradation of natural hormones. This can be observed at the level of the individual organism, its progeny, populations and subpopulations. All these changes have negative effects on homeostasis, reproduction, development or change the behavior of the affected animals. This work focuses on 7 endocrine disruptors - natural estron, 17β estradiol, estriol, and synthetic 17α-ethynylestradiol, irgasan (triclosan), 4-nonylfenol, bisphenol A in the influent and effluent of wastewater plants in the Czech Republic. The thesis contains an optimization of endocrine disruptors determination in wastewater, a preliminary screening to determinate concentration levels, 24 hours composite samples and monitoring of one selected wastewater plant during a day. The analytical procedure is based on filtration, solid-phase extraction (SPE), gel permeation chromatography (GPC), derivatization and gas chromatography coupled with mass spectrometry (GC/MS). Keywords: endocrine disruptors, wastewaters, Czech...