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Extraction of bioactive substances from black currant pomace
Sedláčková, Lucie ; Štursa, Václav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with extraction of bioactive substances from black currant pomace (Ribes nigrum). The theoretical part contains the botanical characteristics of the plant species Ribes nigrum. It is also devoted to the biologically active substances contained in black currant and possibilities of using black currant in the food industry. The fourth chapter deals with description of phenolic compounds, their distribution and methods of determination of phenolic substances. The fifth chapter describes selected extraction procedures. In the experimental part, there were extracted dry black currant pomace in order to optimize the extraction process and obtain the highest yields of dyes. In addition, were determined the selected chemical and physical characteristics of blackcurrant juice and extracts from blackcurrant pomace. A better solvent was a mixture of water and ethanol in a volume ratio of 1:1. After 14 hours maceration of dry pomace, were obtained 769,9 mg anthocyanins per 100 g of dry material.
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Characterization of organic substances in biochar and their release in the soil ecosystem
Bočán, David ; Doležalová Weissmannová, Helena (referee) ; Mravcová, Ludmila (advisor)
The aim of this master’s thesis was to optimize the extraction of 38 PAH and 7 PCB compounds from samples of commercially available biochar and then apply the most suitable extraction method to real samples of biochar and soil. The concentrations of mentioned compounds were determined by using gas chromatography with mass spectrometry detection. Finally, from these concentrations in individual samples, a rate of release of these compounds from biochar to soil was determined. The theoretical part was focused on summarizing the process of biochar production and its properties. The next part deals with compounds that can be present in biochar, their physicochemical properties and effects on organisms and the environment. Also, a most common ways of extracting and determinating these compounds are mentioned. The final part focuses on soil and its characteristics and the changes it undergoes when biochar is applied to it. In the practical part an extensive optimization of extractions using a PSE extractor and thermal desorption extraction was conducted. After determining optimal conditions for both types of extraction methods, these methods were applied to real samples of biochar and soil. Qualitative analysis was carried out using GCxGC-TOF mass spectrometer and quantitative analysis by MRM method on GC-MS2 mass spectrometer.
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Characterization of organic substances in biochar and their release in the soil ecosystem
Bočán, David ; Doležalová Weissmannová, Helena (referee) ; Mravcová, Ludmila (advisor)
The aim of this master’s thesis was to optimize the extraction of 38 PAH and 7 PCB compounds from samples of commercially available biochar and then apply the most suitable extraction method to real samples of biochar and soil. The concentrations of mentioned compounds were determined by using gas chromatography with mass spectrometry detection. Finally, from these concentrations in individual samples, a rate of release of these compounds from biochar to soil was determined. The theoretical part was focused on summarizing the process of biochar production and its properties. The next part deals with compounds that can be present in biochar, their physicochemical properties and effects on organisms and the environment. Also, a most common ways of extracting and determinating these compounds are mentioned. The final part focuses on soil and its characteristics and the changes it undergoes when biochar is applied to it. In the practical part an extensive optimization of extractions using a PSE extractor and thermal desorption extraction was conducted. After determining optimal conditions for both types of extraction methods, these methods were applied to real samples of biochar and soil. Qualitative analysis was carried out using GCxGC-TOF mass spectrometer and quantitative analysis by MRM method on GC-MS2 mass spectrometer.
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Extraction of bioactive substances from black currant pomace
Sedláčková, Lucie ; Štursa, Václav (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with extraction of bioactive substances from black currant pomace (Ribes nigrum). The theoretical part contains the botanical characteristics of the plant species Ribes nigrum. It is also devoted to the biologically active substances contained in black currant and possibilities of using black currant in the food industry. The fourth chapter deals with description of phenolic compounds, their distribution and methods of determination of phenolic substances. The fifth chapter describes selected extraction procedures. In the experimental part, there were extracted dry black currant pomace in order to optimize the extraction process and obtain the highest yields of dyes. In addition, were determined the selected chemical and physical characteristics of blackcurrant juice and extracts from blackcurrant pomace. A better solvent was a mixture of water and ethanol in a volume ratio of 1:1. After 14 hours maceration of dry pomace, were obtained 769,9 mg anthocyanins per 100 g of dry material.
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Vývoj metody na stanovení steroidních látek ve vodách
PLAČKOVÁ, Lydie
The theoretical part of the Master´s thesis describes steroids, their features, and the methods for their determination in waters. In experimental part three steroid hormones, namely 1,4-androstadiene-3,17-dione (ADD), 1,4-androstadiene-3-one-17(beta)-ol (boldenone) and 17(beta)-estradiol were selected. The compounds were concentrated from water by LLE and SPE extraction and determined by gas chromatography coupled to mass spectrometry. Several experiments were conducted to assess the recovery of specific extraction for studied compound.
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Study of Hydrophobic Domains in Humic Acids
Čechlovská, Hana ; Šimon, Peter (referee) ; Franců, Juraj (referee) ; Pekař, Miloslav (advisor)
Fyzikálně-chemická povaha hydrofobních domén huminových kyselin byla studována z několika hledisek. K objasnění významu fluorescenčních spekter byly vzorky podrobeny sekvenční frakcionaci, která pomohla k částečnému objasnění vlivu vodorozpustných složek, volných a vázaných lipidů na optické vlastnosti huminových kyselin. Výsledky naznačily, že fluorescenční píky tradičně přiřazované superpozici jednotlivých struktur jsou spíše důsledkem agregačních vlastností huminových molekul tvořících vlivem hydrofobního efektu zdánlivě vysoce aromatické struktury. Dále pak bylo zjištěno, že na optických vlastnostech huminových kyselin mají podíl i molekuly, které nemají primárně fluoroforní nebo chromoforní vlastnosti. Tento pohled je v souladu s teorií supramolekulárního uspořádání huminových kyselin. Dále byly studovány agregace, konformační chování a termodynamická stabilita huminových kyselin pomocí metody vysoce rozlišovací ultrazvukové spektroskopie. Bylo prokázáno, že huminové kyseliny mají schopnost agregovat už od velmi nízkých koncentrací (
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