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Ligninolytic systems found their application in the food industry, but they are also used for the degradation of several xenobiotic compounds and dyes. This characteristic is making them be a useful tools for bioremediation purposes, that is why the interest in ligninolytic enzymes is increasing. The main aim of practical part was preparation of immobilized enzyme lignin peroxidase by method CLEA from fungus Piptoporus betulinus, Trametes gibbosa and their cocultivation. Activities of free and immobilized enzymes from these fungus were compared and measured by UV/VIS spectrometer. Conditions of precipitation and immobilization were specified by method CLEA. pH optimum for proteins precipitation were for Piptoporus betulinus pH 7,0, for Trametes gibbosa pH 5,0 and for cocultivation pH 6,0. The best concentration of glutaraldehyd, as a crosslinking agent, was for Piptoporus betulinus and cocultivation 50mM and for Trametes gibbosa 10mM. By immobilization, the activity of all enzymes were successfully increased up by 20 %. After optimalization of CLEA enzymes preparation, other parameters such as pH optimum, stability and temperature optimum and stability were tested. All enzymes had their pH optimum in acidic to slightly acidic environment and temperature optimum was in range from 30 °C to 40 °C. Immobilized CLEA enzyme from cocultivation was the most stable for all the enzymes. Free and CLEA enzymes were tested on synthetic food dyes, while their biodegradable ability was examined. Decrease of dyes was measured on HPLC with DAD detector. The sorption of fungi play an important role in this experiment, because fungi created mycelium and partially sorbed the dye. From this point of view, higher decolorization of dye in free enzymes in comparison with CLEA was observed. The best ability of decolorization was shown by a free enzyme from a Trametes gibossa, which after 14days of cultivation decolored more than 90 % dye. In total, significant decolorization (more than 80 % during 14 days) was achieved for azorubin. Degradation of dyes by CLEA was not so effective, which could be possibly caused by cultivation of enzymes without their substrate (veratrylalcohol). Cocultivation technique is very promising method how to increase LiP activity and concurrently create enzyme with improved properties.

The diploma thesis deals with the effects of abiotic stress on seedlings of Norway spruce (Picea abies (L.) Karsten), the impact of water deficit and abundance. In the theore-tical part is described the importance of water in plant, stress and its impact on plants and the cultivation of plants in vitro. Experimental part consists of experiments in vitro. Waterlogging conditions were simulated the medium without agar, drought conditions were created by increasing concentration of sucrose and polyethylene glycol. In the course of experiment were measured plant responses to stress, concentration of ethylene, ethane and CO2 in the culture vessels. At the end of the experiment was measured concentration of O2, quantum yield of photosynthesis, plant growth parameters, content of plant pigments in needles and anatomical changes in the stem and root of Norway spruce.

This thesis concerns experiments with natural compounds and vitamins. In the first part I described these substances, which I proved by chromatography or I made other experiments with them in the second part. I created four worksheets with instruction for laboratory practise. There are thein solutions in the supplement. I verified these four experiments at Grammar School in Prague 9.

This thesis named "Analysis of natural organic dyes and pigments by mass spectrometry" investigates the identification of selected natural organic dyes and pigments by qualitative Laser Desorption/Ionisation - Time of Flight Mass Spectrometry analysis (LDI-TOF MS). The advantage of LDI-TOF MS method is its quick and reliable identification of low molecular weight material without preparatory chemical or time-consuming modification of samples. This method can be used for the analysis of works of art or for verifying their authenticity thanks to requiring only a little amount of sample. The LDI-TOF MS was tested on 19 organic dyes and pigments (e.g. alizarin, apigenin, baicalein, flavone, xanthone, tannic acid), four exemplarily prepared lakes (alizarin, purpurin, chrysin a quercetin lakes) and lakes mixed with organic binding media. The method was also successfully applied to two samples of blue color that were taken from Josef Čapek's painting called 'Procházka' (The Walk), that was dating back to 1936.

The aim of this diploma thesis was to find out the change of the hue lightness saturation after the change of composition of dyeing liquor. The reactive dye Bezaktiv rot S-B was used for dyeing cotton. Dyeing was performed in the laboratory by exhaustion method with two concentrations of dye 0,5 and 2 %. The influence of the change of alkali and electrolyte concentration additions to dyeing bath liquor at different liquors dye ratio was studied. Sodium chloride and Glauber's salt as elektrolyte were used. The dyed samples were washed and then fixed by two types of fixative agents REWIN ACP and REWIN EL. After that the measurement of hue control and the evaluation of fastness to water and rubbing fastness were done. The results were displayed in L*a*b* space and CIE differences between chosen standards and samples were performed by Datacolor International DC 3890.

This diploma thesis deals with comparison of the properties of chokeberry spreads of different origins, composition and different production technologies. The theoretical part contains a brief description of the chokeberry – Aronia melanocarpa, an overview of the most important substances contained in the chokeberry and examples of the use of aronia, not only in the food industry. Furthermore, the legislative requirements for the production of spreads and the production technology itself are described. In this thesis is also described a new patented technology of spread production using HTD technology. Another part of the theoretical part is a literature review of the determination of anthocyanins in chokeberry by HPLC method. The experimental part describes the laboratory procedures used for determination of dry matter, carbohydrates by HPLC with ELSD detector, anthocyanin dyes, total phenolic compounds and antioxidant activity. Another part of the work was a questionnaire survey and sensory analysis of selected chokeberry spreads. The panel members prefered the Lowicz chokeberry spread, for which was determined 29,39% dry matter, 15,15 mg.g-1 anthocyanins, 9,20 mg.g-1 total phenolic compounds, 158,42 mg.g-1 fructose and 151,26 mg.g-1 glucose and the antioxidant activity was determined to be 5,94 mg.g-1.

The main aim of doctoral thesis was the study on reactivity, transport and barrier properties of biocolloidal and synthetic polymeric substances by simple diffusion techniques. It was studied mainly the influence of basic physic-chemical parameters (temperature, concentration, pH and modification of material) on the reactivity and barrier ability of chosen compounds. Further substances were chosen as a model compounds: biocolloids (humic acids, alginate, chitosan, hyaluronate) and synthetic polymer (polystyrenesulfonate). Reactivity, barrier and transport properties of chosen substances were studied by interactions with oppositely charged basic organic dyes (methylene blue, rhodamine 6G, amido black 10B respectively) in hydrogels medium based on linear polysaccharide (agarose). The attention was also paid to basic physic-chemical characterisation (infrared spectroscopy, rheology, elemental analysis, thermogravimetry and scanning electron microscopy) of chosen materials and also hydrogels. Key part of the whole doctoral thesis was the optimization of selected diffusion techniques (diffusion cell technique and non-stationary diffusion in cuvettes) designated for the study on reactivity and barrier properties of wide range compounds (optimized method should be used as an universal method for simple and fast determination of reactivity of different compounds at given or changing conditions). The rate of reactivity, transport and barrier properties was determined based on fundamental diffusion parameters such as diffusion coefficients, break-through time so called lag time, interfacial concentration of chosen organic dye, apparent equilibrium constant, tortuosity factor, partition coefficient.

This diploma thesis deals with testing, optimazing and comparing methods for the identification of bacteria producing polyhydroxyalkanoates. Work included cultivation and microscopy methods, wherein the bacterial cells were stained with lipophilic dyes Nile red and Sudan black. Further, we also used flow cytometry and spectroscopic methods - Raman spectroscopy and infrared spectroscopy with Fourier transformation, and molecular biological methods, which analyzed the presence of a gene encoding PHA synthase (phaC) by polymerase chain reaction (PCR). PCR assay consist of two reactions, the firt on eis based on amplification of phaC gene along with 16S rRNDA gene, which is common for all the bacteria (multiplex PCR). The second reaction is focused on specific amplification of PHA synthase catalyzing biosynthesis of mcl-PHA. In order to overcome false positive results typical for methods analyzing genotype and also to avoid false negative results occuring in fenotype analyzing methods, the best strategy is to combine both aproaches. According to our results, analysis of presence of phaC gene by PCR can be combined with methods capable of determining presence of PHA in bacterial cells. For this purpose, Raman microspectroscopy seems to be very promising tool, since it is able to detect low content of PHA in cells and PHA can not be confused with other lipid metabolites. The results provide an overview of test methods, their advantages and disadvantages and also to compare different criteria according to which it is possible to choose the method of identification in depending on the adjustable requirements.

This thesis was focused on a determination of nadroparin using sequential injection analysis and flow injection analysis with fluorimetric and spectrophotometric detection. The principle of determination was based on the interaction of nadroparin with phenothiazine dye. Methylene blue was used as phenothiazine dye. The determination was performed on a laboratory made FIA instrument and on the commercial SIA instrument. Optimal conditions for SIA were concentration of dye 6 ∙ 10-5 mol dm-3 , injected volume 100 µl, flowrate 1,5 ml min-1 , for FIA: concentration of dye 3 ∙10-5 mol dm-3 flowrate 2 ml ∙ min-1 , injected volume= 100 µl, for fluorimetric detection was sensivity of the detector 1000 V, Emission was measured by 2 nm and excitation wavelenght 621 nm. For spectrophotometric detection, absorbance was detected at the absorption maximum wavelength. Repeatability ranged from 2.01 to 2.85%. The limit of detection for FIA was 0.05-0.09 IU ml-1 , for SIA were limits of detection in range 0,25 - 1,63 IU ml-1 , limits of quantification in range 0,83 - 5,44 and linear range was from 0,5 - 20 IU ml-1 . The limits of detection, limits of determination and the linear range could be corrected for the SIA by the injected volume of phenothiazine dye.