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Detailed characterization of pyrolysis oil by separation techniques and mass spectrometry
Žvaková, Veronika ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The aim of this work is detailed characterization of pyrolysis oil by advanced analytical separation methods and mass spectrometry. During the pyrolysis process decomposition of complex organic material take place in the presence of high temperatures and the absence of oxygen. Condensable part of vapours and aerosols forms viscous liquid called pyrolysis oil which is a complex mixture of large amount of compounds. In this work samples from microwave pyrolysis of woodchips and sewage sludge from wastewater treatment plant Brno-Modřice were analysed. Samples were provided by Bionic Laboratories company. Samples were separated by column chromatography on activated silica. For detailed characterization of each fraction gas chromatography with mass spectrometry detection and comprehensive two-dimensional gas chromatography with mass spectrometric detection with time of flight analyser were used. Substances that have been identified can be divided into several groups: alkanes, alkenes, aromatic hydrocarbons, polycyclic aromatic hydrocarbons, alcohols, aldehydes, esters, carboxylic acid and heterocycles.
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Stanovení vybraných obsahových látek ve vínech metodou kapalinové chromatografie
Hermanová, Veronika
This thesis deals with the analysis of wines using high-pressure liquid chromatography in order to analyze the content of alcohols, organic acids, and carbohydrates in wine. The most important groups and their representatives are presented in the literary review, as well as the theoretical basis of chromatographic methods, selected types of detectors, and used stationary and mobile phases. In the experimental part, analytical parameters of wines from the retail network, laboratory-prepared must and wines prepared by fermentation were measured using liquid chromatography methods with refractometric and UV detection. The results indicate the suitability of this combination of detectors for the selected wine analyses.
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Estery karotenoidů v potravinách a potravinových doplňcích
MICHALČÍKOVÁ, Anna
Carotenoids are lipophilic dyes; their production is very important for photosynthetic processes as well as for tissue protection in leaves and as attractants in fruits. They are also crucial in human/animal nutrition for their antioxidant effects. Carotenoids can be found in plant and animal tissues both in free and esterified forms. The main goal of this bachelor thesis was to establish the method of saponification of carotenoid extracts from fruits, food supplements and subsequent analysis of the presence of carotenoid esters by HPLC. Saponification was tested with sodium and potassium hydroxides. Content of carotenoid esters was detected in food samples and in selected food supplements with presumed high carotenoid content. Findings are discussed in terms of carotenoid uptake in human digestive tract.
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Targeted analysis of branched-chain faty acid esters by LC/MS
Březinová, Marie ; Kuda, Ondřej (advisor) ; Vrkoslav, Vladimír (referee)
Lipidomics as a part of metabolomics is a fast-growing area of research due to the improvement in analytical techniques. This master thesis is focused on lipid extraction techniques optimization, using liquid liquid extraction and solid phase extraction as pre-separation methods and ultra performance liquid chromatography coupled with mass spectrometry for extraction and subsequent identification of branched-chain fatty acid esters (FAHFA - branched-chain Fatty Acid esters of Hydroxy Fatty Acids). This newly discovered class of lipid molecules is associated with insulin secretion, which could improve whole body and local glucose metabolism, providing potential for diabetes 2 type treatment. Solid phase extraction of biological samples was optimized on columns regarding to sorbent composition using reversed phase columns with modified styrene divinylbenzene polymer or octadecyl-bonded polymer and normal phase columns packed with silica gel. Column Strata SI-1 Silica was the most effective for FAHFA separation from biological samples. Chromatographic separation of FAHFA was performed on UPLC Ultimate 3000 RSLC equipped with Kinetex C18 1,7 µm, 2,1 x 150 mm column using gradient program. UPLC was coupled to QTRAP 5500/SelexION, a hybrid, triple quadrupole, linear ion trap mass spectrometer equipped...
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Detailed characterization of pyrolysis oil by separation techniques and mass spectrometry
Žvaková, Veronika ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The aim of this work is detailed characterization of pyrolysis oil by advanced analytical separation methods and mass spectrometry. During the pyrolysis process decomposition of complex organic material take place in the presence of high temperatures and the absence of oxygen. Condensable part of vapours and aerosols forms viscous liquid called pyrolysis oil which is a complex mixture of large amount of compounds. In this work samples from microwave pyrolysis of woodchips and sewage sludge from wastewater treatment plant Brno-Modřice were analysed. Samples were provided by Bionic Laboratories company. Samples were separated by column chromatography on activated silica. For detailed characterization of each fraction gas chromatography with mass spectrometry detection and comprehensive two-dimensional gas chromatography with mass spectrometric detection with time of flight analyser were used. Substances that have been identified can be divided into several groups: alkanes, alkenes, aromatic hydrocarbons, polycyclic aromatic hydrocarbons, alcohols, aldehydes, esters, carboxylic acid and heterocycles.
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Sekundarní aromatické látky ve Svatomartinských vínech
Mamráková, Lucie
This thesis deals with selected ingredients of the chemical structure of wine. Greater attention is given to a smaller group of substances which have a positive influence on the aroma of wine. It describes the creation and concentration in wine. The most important of these compounds are esters. The first section describes " Svatomartinské víno", the varieties and technology suitable for the production of these wines. Trade brand name "Svatomartinské víno" may be used by any wine producer registered in the Czech Republic who is capable of meeting the criteria Wine fund Czech Republic. In this work we can find mention of yeasts, which have a bearing on the final aroma of wine. Finally, in this work we find methods for determining aromatics, of which the best known methods include chromatography coupled with mass spectrometry.
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Aromatický profil mladých vín
Tomanová, Barbara
Aromatic compounds belong to the most valuable substances that give the wine a distinctive expression and are important for sensory evaluation of wine. We chose two samples of white wine - Grüner Veltliner and Sauvignon, where we have set aromatic compounds. Wines were concluded with two different closures (screw cap and classic cork) and then these wines were stored for one year in two conditions different especially by temperature - cool in the cellar and at room temperature. After a year of storage, we have set the aromatic compounds again. The most significant decrease was in the esters of higher alcohols with acetic acid (especially isoamyl acetate and hexyl acetate). These esters are typical for young wines and give them fruitiness particularly. The decrease of these substances was detected in both conditions of storage, but during storage at room temperature was more pronounced. Impact of the closure wasn`t proved. Temperature is a very important factor which influences the aromatic compounds during storage.
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