Keywords: ambient ionization techniques; mass spectrometry; desorption electrospray ionization; desorption atmospheric pressure photoionization; thin layer chromatography; lipids, mass spectrometry imaging Ambient ionization technique in mass spectrometry is an ionization, which carries out in open space outside the machine and which does not require any, or only a minimal sample pretreatment. DESI (desorption electrospray ionization) and DAPPI (desorption atmospheric pressure photoionization) equipped with software control of the spray emitter position for analysis of low molecular organic compounds were investigated in this thesis. These methods use a spray of solvents for desorption and ionization molecules from solid substrate. Conditions for the successful analysis of phospholipids, wax esters and some other compounds were developed. Ambient ionization techniques were quantitatively compared. The application was HPTLC/DESI-MS of lipid's mixture and HPTLC/DAPPI-MS of vernix caseosa. DAPPI-MS was applied for the analysis of termites of Prorhinotermes genus (Isoptera, Rhinotermitidae). Pilot experiments of two dimensional analysis and mass spectrometry imaging were realized.

One theory concerning the invasiveness of exotic plants suggests that they exude allelopathic compounds that are novel in areas being invaded. Here, I tested for allelopathic effects of root exudates of the invasive plant Heracleum mantegazzianum (giant hogweed) in a series of experiments both in vitro and in the garden, and compared them with effects of its native congener H. sphondylium (common hogweed) and two less related native species. Moreover, I addressed intraspecific variability of allelopathy by comparing effects of 41 different maternal lines of H. mantegazzianum sampled from several areas and populations within the Czech Republic. Not only the effects, but also the identity of allelopathic compounds was investigated. In order to test also for the interaction of allelochemicals with soil microorganisms, I analysed the composition of soil microbial communities expressed as phospholipid and neutral lipid fatty acids (PLFA and NLFA, respectively) together with nutrient conditions and light availability at invaded sites in the Czech Republic. The results show that H. mantegazzianum is able to exert phytotoxic effects in vitro as well as in the garden experiment; however, its effects did not differ from the inhibition caused by the native species tested. Variation partitioning among areas,...

A set of 15 carboxylic acids of various structural types was used to test a new procedure of esterification of these substances in the urine without previous extraction. The acids were first measured by a reference method without the matrix, and then by a procedure, where lyophilized urine was treated with derivatizing reagent alcohol·HCl, which was then evaporated, the residue dissolved in water, esters extracted into an organic solvent and subsequently determined by GC/FID and GC/MS. The work is mainly focused on 2-hydroxyethyl- and carboxymethyl-mercapturic acids, but the procedure was also tested on di-, tri- and hydroxy-carboxylic acids, known as physiological urinary components or markers of metabolic disorders. Key words: carboxylic acids mecapturic acids freeze-dried urine esterification gas chromatography

Normotensive hydrocephalus (NPH) is a neurodegenerative disease that occurs mainly in patients of high age. The disorder causes accumulation of cerebrospinal fluid (CSF), which leads to enlargement of ventricles and pressure exerted on cerebral structures. Clinical manifestations (gait disorders, development of dementia, incontinence) can be easily confused with symptoms of other neurodegenerative diseases; unlike other such disorders, however, NPH can be treated by surgery, if diagnosed in time. Patients are indicated for the procedure by a lumbar drainage test. There are currently no reliable laboratory biomarkers known that could be the basis of NPH diagnostics. In the past, steroids proved to be linked to neuronal activity in neurodegenerative diseases with the help of specific diagnostic markers. An instrumental method has been developed for the purposes of this thesis and it was used to gauge the level of certain steroids in CSF in a sample group of NPH patients and a control sample group of healthy individuals. A significant difference has been found in levels of aldosterone and cortisone. Aldosterone was higher in NPH sufferers, while cortisone levels were higher in the control group. It is crucial to differentiate patients with NPH from patients with similar clinical manifestations during...

A simple method has been developed to determine amino acid loading in solid phase peptide synthesis. The method is applicable for the most common type of synthesis, which use FMOC as protective group and piperidine as a deprotecting agent. Both products of deprotection reaction are separated by HPLC and determined using an UV detector; an internal standard is added. The method gives true values that have been verified by an independent method. The RSD is 1.52%. The method is more accurate than the published methods and allows the determination from the waste of synthesis. The employing of the internal standard eliminated the necessity of dilution accuracy or known volumes.

The diploma thesis consists of theoretical and practical part. In the theoretical part it deals with lipids and their role in human nutrition. I also characterized fatty acids and evaluated their health effects. Subsequently, I studied the theoretical basis of chromatographic methods focusing on gas chromatography, its instrumentation and evaluation. In the practical part I analysed the selected assortment of müsli bars by several producers. I focused on the quality of some müsli bars available on the Czech market, focusing mainly on fat content and fatty acid composition. As far as preparation of samples are concerned, it was necessary to lyophilize them first and then Soxhlet extraction followed. The actual determination of fatty acids was carried out using the method of gas chromatography and the results were statistically evaluated.

The aim of the diploma thesis was to monitor the influence of grass in feed on fatty acid content in eggs. The experiment was carried out on Lohmann Brown Classic hybrids at the age of 12 weeks. Layers were divided into five groups. The feed was enriched by a 5% drop of Trifolium pretense, Trifolium repens, Medicago sativa and Lolium perenne. The control group were fed in a diet containing color-promoting additives. The fattening took three months. Egg samples were collected at the end of the month. Feedin and the power was run ad libitum. The effect of the addition of dried plants was significantly (P < 0,05) to the color of the yolk. A statistically significant (P < 0,05) incerease in palmitic acid in eggs was recorded during the experiment in eggs produced by laying hens which were in diet containing addition of Trifolium pretense and Medicago sativa. A demonstrable increase (P < 0,05) was also observed in laying hens which were fed with a mixture enriched with Trifolium pretense in percent α-linolenic acid content.

The aim of the diploma thesis „Possibilities of using non-traditional fats in food technology“ was to suggest a recipe with the addition of fats and oils, which are not often used in food production technology and then evaluate the influence of the added fats and oils to quality of muffins. The main evaluation method was a bakery experiment, during which a total of 10 muffins samples with different fats and oils were baked. The bakery experiment found that fats and oils affect sensory properties like a taste, smell and flexibility. A sensory least acceptable sample was a muffin sample with the addition of linseed oil. This sample had, in a negative sense, an overly pronounced smell and taste. The best sensory samples were muffins with safflower oil, almond oil and cocoa butter. In the second part of the practical part, fats and oils were subjected to gas chromatography (GC), where the proportion and representation of MK were detected and subsequently the results were compared with the values reported by the importer.

The diploma thesis is devided into two parts – theoretical and practical. The theoretical part deals with fatty acids, their nomenclature and chemical composition. Further the diploma thesis focuses on polyunsaturated fatty acids (PUFAs) – their analytical determination, metabolism, important representatives and influence on human nutrition. The practical part deals with the experiment, in which the fatty acids content was determined in mg/100 g using gas chromatography. Testing was carried out using model animals – rats Wistar Albino and pigs Landrace and Large White. By using statistical processing, the differences in the deposition of PUFAs in the livers of these animals, were compared.

Development and validation of methods for analysis of several drugs or their metabolites are decribed in this thesis. The document is presented as a commentary to the original papers, which were published in peer reviewed journals. Discussion on the optimization of each method is presented and covers also method development and influence of preanalytical aspects. Additionally, examples of the application of the developed methods in clinical pharmacology and toxicology are shown. This dissertation consists of three parts: enantiomeric determination of tramadol and its metabolite, determination of some antihypertensive drugs, and qualitative analysis of benzodiazepines. Development of a method for chiral analysis of tramadol and its desmethylated metabolite O- desmethyltramadol (ODT) in human urine and plasma is described in the first part of the thesis. Tramadol is a centrally acting analgetic drug, which is used as racemate in clinical practise. Each enantiomer displays different binding properties for various receptors: (+)-tramadol preferentially inhibits serotonin reuptake while (-)-tramadol mainly inhibits noradrenalin reuptake. (+)-tramadol is considered 10-times more potent than (-)-tramadol. Major active metabolite (ODT), which is considered to be the main agent responsible for the...