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Development of capillary electrophoretic method for determination of phosphorylated components of bacterial cell membranes
Červinková, Jana ; Čabala, Radomír (advisor) ; Coufal, Pavel (referee)
Title: Development of capillary electrophoretic method for determination of phosphorylated components of bacterial cell membranes Author: Jana Červinková Department: Department of analytical chemistry Supervisor: RNDr. Radomír Čabala, Dr. Abstract: The bachelor work reviews the present state of knowledge of the analyses and determination of phosphorylated compounds present in the bacterial cell membranes. This group of compounds is represented mainly by phosphatidylglycerol, cardiolipine, and phosphatidylethanolamine and minority phosphatidylserine, phosphatidic acid and lysylphospatidylglycerol. Together with fatty acids these substances are the main components of cell membranes and they could be, to a certain degree, applied to either identification of bacteria or the study of bacterial behaviour at different conditions. Partially or fully non-aqueous capillary electrophoresis analytical method with spectrophotometric detection would be developed for their determination. Optimum experimental conditions for the separation of standards of selected compounds should be found within the framework of the bachelor thesis. Keywords: phosphorylated compounds, bacterial cytoplasmic membrane, capillary electrophoresis, thin layer chromatography, Bacillus subtilis.
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Influence of Cholestatic Liver Injury on the Elimination and Transport of Drugs
Brčáková, Eva ; Štaud, František (advisor) ; Tilšer, Ivan (referee) ; Lotková, Halka (referee)
The liver is a unique organ with a number of vital functions. Pivotal one is its participation on bile formation and secretion, import, detoxification and excretion of endogenous substances and xenobiotics. Bile formation is essential for both absorption of lipids in intestine and excretion of various endogenous compounds and xenobiotics (e.g. bile acids, bilirubin, cholesterol, phospholipids and drugs). This function is markedly impaired during extrahepatic and intrahepatic cholestasis with partial or complete stoppage of bile flow. Consequently, hepatic and further systemic accumulation of toxic biliary constituents, such as bile acids and bilirubin, occurs. In an effort to compensate this situation, spontaneous anti-cholestatic mechanisms are activated, which provide alternative excretory routes for toxic accumulating compounds (e.g. renal elimination of bile acids and xenobiotics into urine). These mechanisms include changes in the expression, localization and function of respective transporters in liver and kidneys. Another mechanism with a significant impact on bile formation and transport of compounds between bile and blood is blood-biliary barrier formed by connection of hepatocytes by "tight-junctions" and "gap-junctions". While "gap-junctions" exchange substances among cells,...
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Application of Pd-Catalyzed Reactions to the Synthesis of Lactones
Šnajdr, Ivan ; Pour, Milan (advisor) ; Kotora, Martin (referee) ; Opletalová, Veronika (referee)
Within the framework of this Thesis, a method fot the preparation of 3,6- disubstituted pyranones was developed and 15 final lactones were synthesized, and their cytostatic and antifungal activity was investigated. Principal steps in the preparation of the compounds were Yamaguchi-Hirao alkylation, hydroalumination followed by iodation and Pd- catalyzed carbonylative lactonization. None of the target compounds displayed interesting cytostatic or antifungal activity (IC50 < 10 μmol/L), which was suprising given the significant antifungal activity of analogous butenolides. The development of the synthesis of 3- monosubstituted pyranones is described next. Our strategy is based on the use of 5,6-dihydro-2H- pyran-2-one as the starting material, which was converted into the 3-iodo-5,6-dihydro-2H- pyran-2-one in one step. The key step of the synthesis was Pd-catalyzed Suzuki coupling. Finally, the preparation of α- and β-substituted-γ-alkylidenepentenolides is described. The target compounds exhibited significant cytostatic activity (IC50 < 5 μmol/L) against all tested tumor cells (CCRF-CEM, HeLa S3, HT 29, HL 60, L 1210).
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Factors Affecting Metabolism of Anthelmintics
Forstová, Veronika ; Skálová, Lenka (advisor) ; Machala, Miroslav (referee) ; Chládek, Jaroslav (referee)
Nowadays, anthelmintic therapy is the main method in the fight with parasitic worms. Anthelmintics, as well as other xenobiotics, undergo structural changes by effect of biotransformation enzymes, when lipophilic substances are transformed to polar substances more easily eliminable from the organism. Generally, biological effects of metabolites and parent compound are different. Activity of biotransformation enzymes is thus the fundamental factor influencing velocity of detoxification and elimination of the compound from the body and duration of drug effect as well. Modulation of biotransformation enzymes' activities can lead to changes in pharmacokinetic parameters of drug itself as well as other xenobiotics and thus to the risk of decrease in desired effect and/or increase in adverse effects with corresponding impact on the quality of drug therapy. In addition, possible risk of drug residues' presence in animal products has to be considered in farm animals. Biotransformation of xenobiotics is affected by many physiological as well as pathological factors. These factors can be divided into inter-individual (species, gender, genetic polymorphism) and intra-individual (age, diet, medication, disease, etc.). All these factors cause wide variability in occurrence and activity of biotransformation...
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Flame retardants and their penetration into the terrestrial ecosystem
Chytil, Václav ; Čáslavský, Josef (referee) ; Vávrová, Milada (advisor)
This diploma thesis was focused on the analysis of four compounds from brominated flame retardants group, namely pentabromoethylbenzene, hexabromocyclododecane, hexabromobenzene and tetrabromobisphenol A. Matrices were represented by four soil samples and four seat of fire samples. In addition, bisphenol A was also determined. First of all, process of extraction of analytes from matrices was optimized. Three different extraction techniques were tested (pressurized solvent extraction, microwave-assisted extraction and ultrasound-assisted extraction). Next step was to verify stability of target compounds in strongly acidic conditions and to optimize clean-up of extract by column chromatography. Gas chromatography with electron capture detection (GC-ECD) was chosen as an appropriate analytical method for the determination of brominated flame retardants. Bisphenol A was determined by gas chromatography with mass spectrometric detection (GC-MS). The derivatization of phenolic analytes before their final analytical determination was also essential.
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The chosen validation parameters of method for assessment of aroma compounds in processed cheese analogues
Burdějová, Lenka ; Horváthová, Viera (referee) ; Vítová, Eva (advisor)
This Bachelor‘s thesis deals with the issues of method validation for assessment of aroma compounds in processed cheese analogues. The method is based on the isolation of volatiles from the sample using Solid Phase Microextraction (SPME) and their subsequent determination by gas chromatography. The theoretical part focuses on general characteristics, classification and producing technology of processed cheese analogues. Further, aroma active substances contained in cheese analogues, differences from the classic processed cheese and processed cheese analogues occurring on the Czech market are mentioned. The methods for determination of aroma active compounds with a focus on Solid Phase Microextraction and gas chromatography are briefly mentioned. Within experimental part of the work the linearity and repeatability of the SPME-GC method were verified and detection limits and limits of quantification of selected standards were determined. Then the method was applied to chosen samples of processed cheese analogues with addition of different types of vegetable fats.
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The chosen validation parameters of method for assessment of aroma compounds in elderberries
Christovová, Silvia ; Ürgeová, Eva (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the assessment of aroma active compounds in elderberries (Sambucus nigra L.). In the theoretical part the chemical composition and attributes of elderberries are described. Brief information on their healing properties is also given. The possible processing methods in food industry, as well as the traditional means of use at home, are discussed furthermore. Following chapters describe the gas chromatography method combined with the technique of solid-phase microextraction, utilized for the specification of aroma active compounds. The validation of this method is also included. The aim of the experimental part of the work was to verify a set of the selected validation parameters of the SPME-GC method, specifically linearity, the limits of detection (LOD), the limits of quantification (LOQ) and repeatability. Subsequently, the SPME-GC method was applied on the chosen elderberry juice samples. In total, 37 different volatile aroma active compounds were identified and quantified, 15 of which belonged to alcohols, 9 to aldehydes, 5 to ketones, 5 to esters and 2 other compounds. The chemical composition of individual samples was not uniform; no single sample contained all of the identified compounds.
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Analysis of male sex pheromone of different population of tropic fruit fly Ceratitis capitata (Diptera, Tephritidae)
Ježková, Zuzana ; Bosáková, Zuzana (advisor) ; Jirošová, Anna (referee)
The Ceratitis capitata is a very important agricultural pest, whose reproduction behaviour is controled by chemical signals. Males initiate mating by creating leks, where they release sexual pheromones to attract females. The main goal of this diploma thesis was to determine the influence of host plants on the composition of male sex-pheromones C. capitata and to compare emanations of wild males with those originating from laboratory population. We studied the chemical composition of volatiles, released by calling males C. capitata from laboratory and two wild populations, using two-dimensional gas chromatography with time-of-flight mass spectrometric detection (GC×GC-TOFMS), gas chromatography with electroantennographic and flame ionization detection (GC-EAD-FID). All data were statistically analyzed by multivariate data analyses. Significant differences were observed in the quantitative and qualitative composition of the chemical emanations among males from the three populations. The GC-EAD-FID analyses revealed fourteen antenally active compounds with a possible behavioral function. Isomenthone, geraniol, bornyl acetate, geranyl acetone and ethyl octanoate were newly identified antenally active compounds of C. capitata male sex pheromone. Statistical analyses indicated that males and females of...
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