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The Use of Separation Methods for the Study of Selected Drugs and Pesticides in Water
Burešová, Jitka ; Hajšlová, Jana (referee) ; Chýlková, Jaromíra (referee) ; Kráčmar, Stanislav (referee) ; Vávrová, Milada (advisor)
This work is focused on the study of penetration of pesticides and pharmaceuticals in the aquatic environment. The aim was to develop and verify the optimal method for long-term monitoring of the occurrence of selected pesticides and pharmaceuticals in surface waters. Two frequently used analgesics ibuprofen and diclofenac, and carbamazepine that is used to treat epilepsy, were chosen from the group of drugs. A group of 41 pesticides were selected for monitoring too. The attention was focused on a group of urea pesticides and phenoxyacetic acids, as well as on selected pesticides falling to the group of priority substances or identified as environmental quality standards. Some of pesticides were selected because their consumption in the Czech Republic exceeds 30 tons a year. Liquid chromatography with tandem mass spectrometry (LC / MS / MS) was used for the determination of selected analytes in surface waters. Two optimized analytical method were developed. Ten analytes were determined in negative ion mode and 34 analytes in positive ion mode. Solid phase extraction (SPE) was used for purification and concentration of the samples. Developed methodology was validated and used for monitoring of selected compounds in samples of surface waters from the Morava River basin. Samples were collected on the rivers Morava and Svratka monthly for two years. Samples from the river Blata and stream Nivnička were collected for one year. Surface water samples were also collected from the river Litava. Four samples were taken throughout the length of the flow during one day. Smaller streams were chosen for monitoring because of the probability of occurrence of pesticides. They flow abundantly agriculturally cultivated areas. Drugs ibuprofen and diclofenac were detected in all taken samples, carbamazepine mostly. Among the most commonly occurring pesticides were bentazon, diuron, isoproturon, carbendazim, MCPA, MCPP, propiconazole, tebuconazole and 2,4-D.
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Monitoring the nutritional profile of edible fats and oils after culinary treatments
Chadimová, Markéta ; Vítová, Eva (referee) ; Němcová, Andrea (advisor)
This diploma thesis studies changes in the nutritional composition (especially fat changes) of selected fats and oils after various culinary treatments and during their storage under unsuitable conditions. Fats and oils are classified as so-called triacylglycerols, ie they are composed of glycerol and three fatty acids. It is the fatty acids bound to glycerol that determine the properties of fat and its stability. Eight types of fats and oils (sunflower oil, rapeseed oil, olive oil, coconut oil, linseed oil, butter, ghee and lard) were used for the analysis. The flaxseed oil sample was stored for 3 months in unfavorable storage conditions, ie in the light and in the heat. Other fats and oils were used for frying, baking, stewing, grilling and frying meat and onions. The aim of the work was to compare changes of fatty acids, changes of fat numbers and compare the amount of vitamin E contained in individual oils before and after culinary treatments. The results of the analysis showed that fat samples did not show significant changes in fat numbers, fatty acids or vitamin E after culinary treatments or improper storage. From this I conclude that fats and oils have been exposed to high temperatures and unsuitable conditions for a short time. The largest difference in the composition of fatty acids was measured for sunflower oil, where a higher amount of trans fatty acids was measured after treatment and overall a lower proportion of PUFA was measured than before treatment. As sunflower oil has a high content of polyunsaturated MK and a low smoke point, this result was expected. The highest concentration of vitamin E was found in rapeseed oil.
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Determination of selected phenolic and volatile substances in tea and tea infusion
Stará, Kristýna ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
This diploma thesis deals with the determination of phenolic substances and volatile substances in teas and tea infusions. The work compares teas based on their production technology and country of origin. Phenolic substances were determined by LC / MS. Phenolic substances were divided into catechins and other substances. In methanol extracts, green teas contained higher concentrations of catechins than black teas. From the group of catechins, the highest concentration was found for epigallocatechin gallate in green tea, namely 7,96 mg / g. Black teas contained the most gallic acid of the studied teas. The highest content of gallic acid in black teas was set at 1,84 mg / g. Tea infusions were prepared according to the classic procedures typical for each type of tea. In the infusions, the concentrations of all substances were higher in black teas. Some substances such as gallocatechin gallate, quercetin, coumaric acid and kaempferol were not detected in the infusions of green tea. Volatiles were analyzed by HS-SPME-GC-MS. The aroma of the tea was characterized by the identification of volatile substances in tea leafs. The black teas were characterized by a rich floral and sweet aroma. The green teas were more of a fresh and grassy aroma. The substances linalool, linalyl anthranilate and -Terpinyl acetate were found in all teas.
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Artificial sweeteners and their potential impact on the ecosystem
Vavrčíková, Veronika ; Mravcová, Ludmila (referee) ; Zlámalová Gargošová, Helena (advisor)
This diploma thesis deals with the determination and ecotoxicological assessment of artificial sweeteners. The diploma was focused on monitoring the most commonly used sweeteners, which includes acesulfam-K, cyclamate, saccharin and sucralose. These sweeteners were analyzed by liquid chromatography with mass spectrometry, using solid phase extraction for their concentration. The samples for their determination were taken from wastewater treatment plant in Modrice. Artificial sweeteners are synthetically produced substances, which is the main reason for their occurrence in waste water. Some of them are not efficiently removed from the wastewater treatment plant and penetrate into the environment. Analysis of the samples was found, that sucralose penetrates into the environment. The ecotoxicological effect of the sweeteners was evaluated via aquatic organisms, namely on the freshwater crustaceans Thamnocephalus platyurus and Daphnia magna, on the water plant Lemna minor, and the battery of tests was supplemented by a representative of the destructors Vibrio fischeri. For all sweeteners, LC20, EC20 and IC20 values were determined. For some sweeteners, LC50, EC50 and IC50 values were also determined. During testing, saccharin represented the highest toxicity.
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Analysis of pesticides in the environment using the QuEChERS method
Vašinková, Alena ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis focuses on pesticides in the environment, more specifically in cereals. Pesticides were monitored in various samples of cereals (barley, rye, oats, and wheat) within the thesis. The monitored substances were isolated in selected samples and concentrated using the QUECHERS method. Gas and liquid chromatography were used to determine pesticides. The theoretical part consists of the common types of pesticides, divided by the ease with which these substances into food and their impact on humans and environment. It also mentions current health protection legislation and environmental legislation.
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Benzene in petroleum-derived products and health protection
Bílková, Karolina ; Kořínek, Pavel (referee) ; Stránský,, Vladimír (advisor)
Benzene is very toxic compound, which has carcinogenic and mutagenic effects. Result of these effects is significant reduction of its use and also low hygienic limits in occupational environment and environment. The aim of this diploma thesis was to map out possible exposure to benzene and checking of clasification correctness of motor gasoline and benzine (cleaners, thinners etc.). Determination of benzene was carried out by gas chromatography with flame ionisation detector (GC/FID) and high performance liquid chromatography with diod array detector (HPLC/DAD). Marginally, the diploma thesis was focused on determination of toluene (in june 2007 became effective ordinance no.284/2006 Sb., which forbid to sell products that contain more than 0,1 % of toluene to small consumers). Toluene was determined by same methods as benzene.
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Monitoring process contaminants in coffee roasting using LC-MS
Ilyushchenkova, Alexandra ; Juglová, Zuzana (referee) ; Diviš, Pavel (advisor)
The bachelor thesis focuses on monitoring changes in the concentration of process contaminants during coffee roasting using liquid chromatography with mass detection. Green coffee was roasted at 220 °C for 14 minutes with two-minute intervals. Samples for analysis were taken from 10. by 24. minutes of roasting. Practical monitoring of the acrylamide’s formation during coffee roasting was not carried out, since it was not possible to detect acrylamide in coffee using a mass detector, even after its derivatization with thiosalicylic acid. The relevant data were taken from other scientific articles, which reported a linear increase in concentration with the roasting time up to the maximum value and a subsequent exponential decrease at the end of roasting. By monitoring 5-hydroxymethylfurfural, it was found that during roasting, this substance is gradually formed in coffee due to the decomposition of carbohydrates, however, with increasing roasting time, the degradation of this substance occurs quite quickly. The concentration of 5-hydroxymethylfurfural was also determined in coffee samples purchased in the trade network. Concentrations of 5-hydroxymethylfurfural in these samples ranged from 0,3 to 0,38 mg/kg, which are corresponded to those reported in other expert studies.
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Optimization of concentration determination of degrdation products of uracil via LC-MS
Kavale, Gustav ; Ševčík, Jan (advisor) ; Míšek, Jiří (referee)
In the Czech Republic, tens of thousands of oncology patients undergo treatment based on fluoropyrimidines every year. Many of these patients suffer from negative side effects that can even have a fatal impact. Currently, the best described factor in the cause of the toxicity of fluoropyrimidines is the activity of the pyrimidine catabolism enzyme - dihydropyrimidine dehydrogenase. Due to the high frequency of pathogenic mutations in the dihydropyrimidine dehydrogenase gene, the extreme risk of toxicity affects hundreds of patients in the Czech Republic every year. For this reason, the "European Medical Agency" has issued a recommendation to carry out investigations for the possible occurrence of toxic effects before starting treatment. One of the diagnostic options for determining sensitivity to fluorouracil is metabolomic analysis, based on the quantification of degradation products of uracil metabolism in plasma using liquid chromatography with mass spectrometry. The goal of this work is to perform basic optimization of mass spectrometer parameters for quantification of selected degradation products of uracil metabolism. Keywords: Uracil, Fluoruracil, Liquid Chromatography, Mass Spectrometry
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Phytochemical studies of potential phytopharmaceuticals using separation methods
Dulendarova, Elizabeta Hristiyanova ; Jenčo, Jaroslav (advisor) ; Křoustková, Jana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department: Department of Pharmacognosy and Pharmaceutical Botany Candidate: Elizabeta Hristiyanova Dulendarova Supervisor: RNDr. Jaroslav Jenčo, Ph.D. Title of dissertation thesis: Phytochemical Studies of Potential Phytopharmaceuticals using Separation Methods The main aim of this diploma thesis was the identification of main alkaloidal components from the fraction of Papaver rhoeas L. (family Papaveraceae) alkaloidal extract - fraction PR-12-23. The introduction to the theoretical part summarizes alkaloids found in Papaver rhoeas L. and describes the separation methods used in the isolation process at the department of Phamacognosy and Pharmaceutical botany. Two main compounds within the extract were identified and separated based on HPTLC, HPLC-MS, and GC-MS chromatographic separation methods. For the subsequent fractions, the HPLC method development, optimization, and scaling up from analytical to preparative scale was done. After identification with the help of analytical HPLC and GC, the compounds were separated into fractions, isolated using preparative HPLC, and identified using NMR. The purified isolates were tested for anti-butyrylcholinesterase and cytotoxic biological activity, linked to AD and cancer, respectively. The first...
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