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Characterization of adsorption properties of probiotic bacteria
Černá, Klára ; Sedláček, Petr (referee) ; Obruča, Stanislav (advisor)
The aim of the diploma thesis is to characterize the adsorption properties of probiotic bacteria. Characterization was performed using of designed and optimized spectrophotometric method of determination of adhesion of probiotic bacteria to mucin as the main viscoelastic component of mucus. In order to provide a more detailed description of the adhesion interactions involved in the adhesion of probiotic bacteria to mucin, the viability of selected probiotic bacterial strains Lactobacillus rhamnosus CCM 1825, Lactobacillus plantarum CCM 7039, Lactobacillus delbrueckii subsp. bulgaricus CCM 7190, Lactobacillus acidophilus CCM 4833, Lactobacillus casei CCM 4798, Bifidobacterium breve CCM 7825, Bacillus coagulans CCM 2658 and a potential probiotic strain of Lactobacillus zeae CCM 7069. Moreover, bacterial adhesion to carbohydrates was also determined for all the bacteria tested. The last proposed and optimized technique was dynamic and electrophoretic light scattering characterizing surface properties such as -potential, average size distribution and isoelectric point. From this method, information was obtained on aggregation of bacterial cells and on electrostatic interactions. The combination of these methods was used as a complex tool to characterize adhesion of the tested bacterial cultures as a very specific, sensitive and key parameter of a successful probiotic microorganism that is influence by the multiple effects.
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Determination of selected chemical parameters of fruit of new currant varieties
Pelikánová, Blanka ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Presented diploma thesis is dedicated to the determination of selected chemical parameters of fruits of new currant varieties. The theoretical part is focused on the characteristics of currant, the biologically active substances of its fruits and also the utilization of current in the food industry. Further part of the theory deals with the main chemical parameters which were examined: polyphenols, anthocyanins, ascorbic acid and antioxidant activity. In the practical part there were determined selected chemical parameters in six white, twelve red and thirteen black varieties of currant. Anthocyanins and polyphenols have been determined spectrophotometrically. The content of ascorbic acid in selected varieties of currant was determined by HPLC. As a technique for the determinationof the antioxidant activity was selected the method of free radical DPPH.
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Control and monitoring of parameters in microfluidic systems
Meloun, Jan ; Sekora, Jiří (referee) ; Čmiel, Vratislav (advisor)
This thesis discusses the construction of Microfluidic systems for a microscope. The theoretical part of this thesis deals with cell and its survival in the environment. Furthermore, light, light’s behavior and optical spectral analysis in some methods is discussed. Also, the use of the development platform Arduino with wireless data transfer for data visualization is mentioned. Methods for measuring pH are mentioned as well. The practical part is dedicated to the construction of the Microfluidic system with the use of Arduino, smart mobile devices and a developed mobile application including controlling liquid flow with the measured data visualization.
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Generation of ozone by photochemical processes in O2 and admixtures
Tomečková, Klára ; Blahová, Lucie (referee) ; Mazánková, Věra (advisor)
Ozone is a toxic gas with the fatal impact to living organisms at high concentrations. Therefore, this gas is useful in sterilization in many cases. The subject of this work is the generation of ozone using various methods and determination of its concentration. Then the generated ozone can be used in ozone therapy. The theoretical part deals with properties and use of ozone. In addition, information gathering connected to ozone was performed. It was about methods of ozone generation and subsequently about the diagnostics determine of ozone concentration. In the experimental part the ozone generation and determination of its concentration was performed using spectrophotometric method and iodometric titration. The ozone concentration in the air was also measured over the long term using the Schönbein method.
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Study of stress markers in plants influenced by heavy metals
Rucký, Jakub ; Beklová, Miroslava (referee) ; Provazník, Ivo (advisor)
In our experiment, we examined the influence of Cd2+ in plant tissue culture of sunflower cultivar Aloha. Plant tissue culture were exposed to concentrations of 0, 5, 10, 50, 100 and 500µM for 7 days and were monitored changes in its antioxidant activity. We used monitoring methods ABTS, FRAP, Free Radicals and DPPH. To compare the results obtained, measured data were used program STATISTICA. The objective of statistical evaluation is to determine the concentration at which the plants are still able to withstand the negative effects of non-fatal.
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The occurence of Cadmium in environment
Bělohlávková Staffová, Petra ; Řezáčová, Veronika (referee) ; Sommer, Lumír (advisor)
Heavy metals, including cadmium, belong to the contaminants of the environment. With permanently increasing pollution, there is an increase of these metals in the water, in the air and in the soil, which are involved in the food chain and subsequently the food of human. Cadmium has received considerable attention for its toxicological properties. Similarly, monitoring of cadmium in the Czech Republic is relatively large. There is a legislative measure regarding not only the permitted level of cadmium in the air, in the water, in the soil, but also food and is also restricted its use in the industry. Further they developed methods of its determination. In this work was devoted to attention photometric determination and some electroanalytical methods, then spectrometric methods mainly atomic absorption spectrometry and atomic emission spectrometry, which is currently the most widely used.
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Transport properties of dextran-based hydrogel systems
Vyroubal, David ; Kalina, Michal (referee) ; Klučáková, Martina (advisor)
This bachelor thesis is focused on study of transport properties of dextran-based hydrogel systems. The aim of this work is to determine their ability to absorb and release substances. Nile red was used as a probe to examine the transport properties of these systems. All hydrogels were prepared by the so-called wet way. At first stock solutions of dextran and surfactants were prepared and subsequently mixed to form a hydrogel. Nile red was dissolved in the surfactant stock solution and colored gels were formed upon mixing with dextran stock solution. Several types of gels were thus formed which differ in the concentration of the surfactant and nile red used. Supernatants were spectrophotometrically measured at various time intervals. For study of transport properties in multiple surroundings, the original supernatant was replaced after hydrogel preparation with a surfactant solution or physiological saline solution.
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