This diploma thesis deals with the stability and basic properties of combined beverages and fruit concentrates. The theoretical part describes the production and use of fruit concentrates. Furthermore, the work deals with anthocyanic pigments and phenolic substances. The principle and instrumentation of liquid chromatography and electron paramagnetic resonance were described. In the next subchapter, the methods of determination of total anthocyanins and phenolic substances were described. The experimental part of the thesis described the determination of soluble solids, viscosity and antioxidant activity. The total content of phenolic compounds were determined by the Folin-Ciocalteua method and the total anthocyanins were determined by the pH-differential method. In the samples were determined cyanidine-3-glucoside and cyanidin-3-galactoside by liquid chromatography.

This master's thesis deals with a present problem of alternative dental fillings, which should replace amalgam fillings. Although there are health concerns about these alternative materials, especially resin composite fillings raise concerns, because they release potentionally harmful substances into the oral cavity. Accordingly even this medical device subjects various tests before releasing to the commercial market and one of these tests was carried out according to ČSN EN ISO 10993 and available scientific literature in the experimental part of this thesis. The amalgam controversy, substances used for manufacturing of resin dental fillings and analytical methods are described in the theoretical part of the thesis. In the experimental part of the thesis, 30 days long cumulative extraction experiments were carried out into various extraction mediums in order to assess suitability of new dental resin filling from ADM, a.s. by comparison with commercially available dental material from company GC EUROPE N.V. These samples were analysed by LC-MS and the amount of eluted substances from dental composites to extraction medium was quantified.

The diploma thesis is dealing with monitoring of arsenic in foodstuffs. The aim of this thesis is the determination of arsenic in samples of fish and rice and the study of forms, in which arsenic occurs, using speciation analysis. Arsenic is known as a toxic element, but its measure of toxicity depends on the chemical form it occurs in. Arsenic is present in the environment naturally or it gets in the environment by human activities. Complete characterization of arsenic compounds is necessary to understand intake, accumulation, transport, detoxification and activation of this element in the natural environment and living systems. The field of arsenic speciation analysis has grown rapidly in recent years, because determination of the total element content is not sufficient in the case of arsenic. Speciation method was done using separation by high performance liquid chromatography and detection by atomic fluorescence spectrometry with hydride generation. Extractable arsenic was present in the form of nontoxic arsenobetaine in all analysed samples of fish. In samples of rice there was confirmed the presence of toxic inorganic species of arsenic, esspecially As (III), but their concentration was at low level.

Dependence of glutathione concentration on the amount of thallium in the plant was studied. Observed plant was maize (Zea mays) which was divided to two parts – root and overground. Two culture procedures were elaborated where seeds and young seedlings were cultivated in a solution of thallium of concentration 0, 1, 3, 5, 8, a 10 µmol/l. Extraction agents used during extraction were phosphate buffer and solution of ascorbic acid. Determination of glutathione was realized by capillary electrophoresis (CE) and high performance liquid chromatography (HPLC). Diode array detector (DAD) was used in both methods. Quantification of the thallium amount in the plant was done by method of inductively coupled plasma-atomic emission spectrometry (ICP-AES).

The aim of this diploma thesis is focused on determination of B vitamin in food especially in malting barley and malt. This diploma thesis is consists of theoretical and experimental parts including the conclusion and supplements. Theoretical part describes thiamine characteristic, chemical structure, chemical and physical properties, function of thiamin in organism, impact it´s insufficiency to the human health, occurrence in common food and methods for it´s determination. Further are describing theoretical principles of high-efficiency liquid chromatography, chromatography on reverse phase, derivatization and ways of validation. In the Experimental section is detailed description of used method for determination of thiamine in barley and malt, fresh mash and beer but also in common food supplements as are B-kompex, Pangamin and Thiamin. Determination was made by high-efficiency liquid chromatography on reverse phase with isocratic elution and fluorescent detection. Next part introduce the results of theses, discussion of experimental work, volume of thiamine in analyzed food and validation parameters of used method. In the conclusion are valorized results of experimental work. In the attachment are graphs of standard curves, chromatogram and calculations of validation parameters. Diploma thesis was realized in laboratory of Chemistry and Technology of Foodstuff, Faculty of chemistry, Brno University of Technology.

This diploma thesis deals with determination of carbohydrates in wine. Theoretical part attends to production of wine from grape to treatment and training of wine. It refers saccharides in wine, especially glucose and fructose. The study provides an overview of the available sources concerning the possibilities of determination of carbohydrates in wine by chromatographic methods and Skalar automated chemistry analyser. The study shortly refers simple analytical methods for determination of wine saccharides. The experimental part based on this search deals with analysis of saccharides by high performance liquid chromatography with refractive index detector and UV detector on aminoalkyl column and determination of reducting sugars by Skalar automated chemistry analyser. Finally, the results of these methods were compared.

The aim of the theses was determination of selenium species in yeast Saccharomyces cerevisiae cultivated in medium with added inorganic form of selenium (Sodium Selenite). Concentrations of Sodium Selenite in cultivation medium were 0,1; 1; 10 and 100 mg.l-1. Cultivation was undertaken in fermenting tub for period of 72 hours. Cultivated yeasts were extracted by use of enzymes and subsequently the species of selenium in particular parts of yeasts were determined. In order to determine selenium species, the method of high-performance liquid chromatography in combination with atomic fluorescent spectrometer and technique of hydride generation was used. Having analysed different fractions of the yeasts Saccharomyces cerevisiae it was ascertained that during cultivation the sorption of selenium occurred in form of Se4+ in cell membranes while in cytoplasm no inorganic forms of selenium were found. Furthermore, it was stated that yeasts Saccharomyces cerevisiae are able to metabolically change inorganic forms of selenium to organic forms (selenomethionine), while these forms are present in cytoplasm and they are likely to be bound to proteinic structures of cell membranes. An increase of concentration of Se4+ in cell membranes could be observed as a result of increasing concentration of Sodium Selenite in cultivation medium. In proteinic structures the concentration of organic selenium forms increased only to concentration 10 mg.l-1 of Sodium Selenite in cultivation medium.

The purpose of this thesis is to compare the contents anthocyans in different varieties of European elderberry (Sambucus nigra L.). It was also studied the relationship between the content anthocyans in selected samples of blue grape varieties (Vitis vinifera L.) and position of the track, where the grapes were grown. The theoretical part describes elderberries and grapes in terms of botanical, chemical, and in terms of their using in the food industry. The dominant part of this chapter is to describe anthocyans and possibilities for their determination in the elderberry and grapes. Emphasis has been placed on the pH-differential method and determination by high performance liquid chromatography. The experiments are divided into two parts. The aim of the first experimental part is comparison of the total anthocyanins content in fifteen varieties of elderberry. The performed analysis shows that in terms of anthocyanins content for cultivation of elderberry in the Czech Republic the most suitable varieties are Mammut, Samyl, Reis aus Vossloch and Haschberg. In the second part of the experiments were determined total anthocyanins content in nine varieties of blue grape grown in the Mikulov region. For determination were used HPLC and pH-differential methods, as well as in the first part. The highest content of pigments was found in varieties Alibernet and Neronet. The present study focused on the suitability of the location pointed to vineyard south to southeast orientation plantings. At the end of the experimental part is a comparison of both methods of determination. Method using high performance liquid chromatography to provide very accurate results compared to less demanding pH-differential method of determination. This is recommended only for tentative determination of anthocyanins content in real samples.

This master’s thesis is focused on optimizing of the analytical method for the determination of selected drugs - estrone, estradiole, ethynylestradiol, estriole, diethylstilestrole, norethindrone, mestranole and progestrone in wastewater using liquid chromatography with mass spectrometry (LC/MS). Solid phase extraction (SPE) using Oasis HLB cartridges was chosen extraction method Different mobile phase, temperature, flow rates and mobil phase gradient were during the process of optimization. Samples of the wastewater were collectedat the inflow and outlow of the wastewater treatment plant in Břeclav and in University of Veterinary and Pharmaceutical Sciences Brno. Drugs were isolated from wastewater and preconcentrated using solid phase extraction (SPE) and determined by high performance liquid chromatography with mass spectrometric detection (HPLC/MS).

The thesis focuses on the use of passive sampling during an analysis of hormones in drinkable water. In the theoretical part there are described selected passive samplers and the sample of the type of POCIS is described at fuller length. The next chapter engages with steroid hormones and an input of estrogenic hormone into the environment. The thesis contains chapters dealing with possibilities of the determination of hormones in water. It is specialized on the analysis of drinkable and surface water. In the last chapter of the theoretical part there are introduced water works where samples for an experimental assessment were collected from. The experimental part of the thesis presents the specification of the extraction of analytes and an adjustment of used device. In the thesis there are specific calibrations for individual assessment of hormones. The results of the assessment for each collection point are ordered to a well-arranged table. Increased levels of targeted estrogens were not approved in most of sampling points.