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Determination of sweeteners and preservatives in energy drinks by HPLC
Zídková, Anežka ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This master´s thesis is focused on simultaneous determination of sweeteners and preservatives in energy drinks by liquid chromatography coupled with DAD and ELSD detection. The method was optimized for determination of aspartame, acesulfame K, saccharin, sucralose, steviol glycosides, benzoic acid and sorbic acid. Analyses were carried out on the Poroshell 120 EC-C18 column (4.6 x 150 mm, 2.7 m, Agilent) using mixture of methanol, acetone and water with formic acid and trimethylamine as a gradient mobile phase at a flow rate 0,5 mL•min-1. Validation parameters were determined (limit of detection, limit of quantification, repeatability and recovery). The validated method was applied on real samples.
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Removal of selected organic pollutants from water using advanced oxidation processes
Dalajková, Nikola ; Vávrová, Milada (referee) ; Repková, Martina (advisor)
The aim of this diploma thesis is the determination of selected organic pollutants with a focus on artificial sweeteners in waste water from wastewater treatment plant (WWTP) Modřice and the subsequent degradation of the thus obtained concentrations in model water using advanced oxidation processes (AOP). Two sweeteners were determined, namely sucralose and saccharin found in waste water. Synthetic sweeteners are not sufficiently cleaned in the WWTP and penetrate the environment. Effective processes for removing organic substances, including alternative sweeteners, are AOP processes. These processes are based on reactions of highly reactive hydroxyl radical (OH·), which is produced by many chemical reactions. Generally, they use ozone (O3) and hydrogen peroxide (H2O2). On sampling, wastewater samples were treated with Solid Phase Extraction (SPE) and then evaluated by HPLC/MS (High Performance Liquid Chromatography). In observing the degradation of selected sweeteners, three AOP methods were used: O3/UV, H2O2/UV and O3/H2O2. For each of these methods, the efficiency of degradation of sucralose and saccharin was investigated. From the evaluated data it was found that the most efficient AOP process for removing artificial sweeteners from water is the O3/H2O2 method.
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Determination of sweeteners and preservatives in energy drinks by HPLC
Zídková, Anežka ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This master´s thesis is focused on simultaneous determination of sweeteners and preservatives in energy drinks by liquid chromatography coupled with DAD and ELSD detection. The method was optimized for determination of aspartame, acesulfame K, saccharin, sucralose, steviol glycosides, benzoic acid and sorbic acid. Analyses were carried out on the Poroshell 120 EC-C18 column (4.6 x 150 mm, 2.7 m, Agilent) using mixture of methanol, acetone and water with formic acid and trimethylamine as a gradient mobile phase at a flow rate 0,5 mL•min-1. Validation parameters were determined (limit of detection, limit of quantification, repeatability and recovery). The validated method was applied on real samples.
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Sugar substitutes
Žuffová, Frederika ; Drastík, Martin (advisor) ; Kuchařová, Monika (referee)
The aim of diploma thesis "Sugar substitutes" was to create a list of sugar substitutes and review their impact on human health. It analyzes the realtionship of sugar substitutes to obesity, diabetes and caries. Diploma thesis discusses the possibilities of using sugar substitutes and their characteristics. Thesis includes information about acceptable daily intake of each sweetener and comparison its sweetness to sucrose. The brief description of every group of food additives and chapter about valid legislation are also parts of this thesis. Key words: sugar substitutes, artificial sweeteners, additives, acceptable daily intake, diabetes mellitus, obesity, caries
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Removal of selected organic pollutants from water using advanced oxidation processes
Dalajková, Nikola ; Vávrová, Milada (referee) ; Repková, Martina (advisor)
The aim of this diploma thesis is the determination of selected organic pollutants with a focus on artificial sweeteners in waste water from wastewater treatment plant (WWTP) Modřice and the subsequent degradation of the thus obtained concentrations in model water using advanced oxidation processes (AOP). Two sweeteners were determined, namely sucralose and saccharin found in waste water. Synthetic sweeteners are not sufficiently cleaned in the WWTP and penetrate the environment. Effective processes for removing organic substances, including alternative sweeteners, are AOP processes. These processes are based on reactions of highly reactive hydroxyl radical (OH·), which is produced by many chemical reactions. Generally, they use ozone (O3) and hydrogen peroxide (H2O2). On sampling, wastewater samples were treated with Solid Phase Extraction (SPE) and then evaluated by HPLC/MS (High Performance Liquid Chromatography). In observing the degradation of selected sweeteners, three AOP methods were used: O3/UV, H2O2/UV and O3/H2O2. For each of these methods, the efficiency of degradation of sucralose and saccharin was investigated. From the evaluated data it was found that the most efficient AOP process for removing artificial sweeteners from water is the O3/H2O2 method.
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Phytoextraction of Artificial Sweeteners from Aqueous Solutions
Luptáková, Dominika ; Smrček, Stanislav (advisor) ; Břichnáčová Habartová, Věra (referee)
The artificial sweeteners are currently worldwide used as food additives. In human organism they are only partially metabolized and then renally excreted. The big amounts of these abiogenic compounds contaminate municipal wastewaters. The efficiency of cleaning process in the sewage treatment plants (STP) is usually for cyclamate about 99 % and saccharine cca. 90 %. Acesulfame K is in STP practically not eliminated. Although most of artificial sweeteners are considered as good degradable, the residues were found in both surface waters and groundwaters. At long-term treatment can these compounds exhibited biological effect such as cancer genesis, gastrointestinal effects and/or surprisingly body mass increasing. The phytoextraction of saccharine and acesulfame K was experimentally studied by using of "in vitro" cultivated plants Helianthus annuus, Zea mays, and Brassica napus. The phytoextraction was monitored as decrease in medium concentration of tested substance in Murashige-Skoog cultivation medium. It was shown, that used species are able to extract tested substances and during 5 to 7 days 30 - 60 % of acesulfam K and 50 - 60 % of saccharine amounts disappear from cultivation medium depending of used plant species. The best extraction ability was observed at Helianthus annuus cultivars - 0.1...
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