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Interaction of Proteins with Low-molecular Substances in vitro. Effect of Glycation, Substances of Plant Origin, and Combination of these Factors on Function and Spectral Properties of Selected Proteins.
Trnková, Lucie ; Dršata, Jaroslav (advisor) ; Patočka, Jiří (referee) ; Mikšík, Ivan (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate Ing. Lucie Trnková Supervisor Prof. MUDr. Jaroslav Dršata, CSc. Title of Doctoral Thesis Interaction of proteins with low-molecular substances in vitro. Effect of glycation, substances of plant origin, and combination of these factors on function and spectral properties of selected proteins. Plant polyphenolic compounds naturally occurring in human diet possess a wide range of biological and pharmacological properties. They can interact with various proteins including enzymes. Their interaction with serum albumin has a great significance because of its ability to bind, transport and store many endogenous and exogenous low-molecular compounds present in blood circulation. One of the objectives of this thesis was to study chemical structure-binding affinity relationships of two important groups of polyphenolic substances, namely hydroxycinnamic acids and catechins (flavanols), with the molecule of serum albumin in the in vitro models using spectroscopic (UV-Vis absorption spectroscopy, fluorescence quenching method) and electrophoretic (native and SDS PAGE) methods. Some polyphenols caused the changes in protein conformation and the relationships between their structures and obtained...
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Modification of glutathione S-transferase by selected glycating agents
Průchová, Zuzana ; Dršata, Jaroslav (advisor) ; Trnková, Lucie (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Zuzana Průchová Supervisor: Prof. MUDr. Jaroslav Dršata, CSc. Title of diploma thesis: Modification of Glutathione S-transferase by selected glycating agents Glycation is a non-enzymatic reaction, which leads to the binding of carbonyl compounds to free amino groups of amino acids, peptides, proteins or other biomolecules. This process is closely related to impaired protein function in diabetes mellitus, during aging, and in neurodegenerative diseases. The main purpose of this thesis was to monitor the impact of several glycating agents on the properties of the enzyme glutathione S-transeferase (GST, EC 2.5.1.18) which plays a key role in the detoxification of many exogenous as well as endogenous compounds. Methylglyoxal (0.5-2 mM), glyceraldehyde (0.5-10 mM), glucose (50 mM), and fructose (50 mM) were selected as glycating agents. The course of protein glycation was evaluated by following methods: GST catalytic activity assessment, determination of primary amino groups, assessment of AGEs formation using fluorescence and Western blotting, generation of high molecular cross-links and aggregates by denaturationg polyacrylamide gel electrophoresis (SDS-PAGE), changes in GST molecular...
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Influence of hydroxycinnamic acids on methylglyoxal-induced protein glycation
Vejvalková, Hana ; Boušová, Iva (advisor) ; Trnková, Lucie (referee)
Author: Hana Vejvalková Publishing place: Charles University in Prague, Faculty of Pharmacy in Hradec Králové Title: Influence of hydroxycinnamic acids on methylglyoxal-induced protein glycation Supervisor: PharmDr. Iva Boušová, Ph.D. The diploma thesis was aimed at potencial antiglycation effect of antioxidants of natural origin (hydroxycinnamic acids) on the modification of bovine serum albumine and asparate aminotransferase by methylglyoxal as a glycating agent. I monitored the effect of hydroxycinnamic acids on generation of glycation products using fluorescent, absorption, and electrophoretic methods. The influence of hydroxycinnamic acids on the glycation of model proteins was ambiguous. The only derivative with proven antiglycation effect on production of non-specific glycation products and pentosidin measured by fluorescence and spectrophotometry was p-coumaric acid in 100 μM concentration. On the other hand, chlorogenic acid 100 μM displayed strong proglycation effects in all methods used for detection of glycation products. The effect of all tested substances was concentration dependent. Results show that the more substituents given acid contained in its molecule, the stronger proglycation effect this compound exerted.
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Low- and nonenergy sweeteners
Trnková, Lenka ; Orsák, Matyáš (advisor) ; Hniličková, Helena (referee)
Low- and no-calorie sugar subtistutes are compounds that provide food with its sweet taste. As the term suggests, they have lower or no food energy and usually are characterized by higher sweetness than sucrose. For that reason, these substances are especially used during the treatment of diabetes mellitus, to reduce the energy content of food or in prevention of dental caries.
Natural sweeteners were discovered a long time ago, during the search for sustenance. For example Stevia was used by South American Natives even before the European conquest of the territory. However, the history of artificial sweeteners is not too significant, because it relates to breaking the laboratory rules. That is how saccharin was invented in 1878.
Sugar substitutes are added to food on purpose, adjusting the taste or extending the shelf life of foods. In the EU, every approved sweetener has got an E-code, which is displayed on the label.
Sugar substitutes can be grouped according to their origin, their nutrition value or their chemical structure. This thesis discusses low- and no-calorie sugar substitutes that can be synthetic or natural. Mentioned synthetic sweeteners typically contain less then 21 kJ per portion. These intensive food additives possess many times the sweetness of sucrose. The main representatives of this group are saccharin, cyclamate, acesulfame K, sucralose and aspartame with its derivatives. The group of natural sugar substitutes constits of substances like erythritol, D-tagatose, trehalose, neohesperidin dihydrochalcone, stevioside and thaumatin.
There are some limitations confirmed by expert studies. For example, patients suffering from diabetes mellitus should mainly use synthetic sweeteners, because of their low nutritional value.
Even though in some states certain sweeteners are forbidden, safety studies say that there are no adverse effects, if the recommended daily intake is respected. Sugar substitutes, therefore, can be considered safe.
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Dotační možnosti realizace rozvoje cestovního ruchu v mikroregionu Horňácko
Trnková, Lucie
This thesis evaluates the use of grant funds from various grant schemes for transnational, national, regional and local level in relation to support the development of tourism. The chosen problem area for the evaluation is the micro-region Horňácko. Review of the literature explains the concepts related to the evaluation of strategic documents, programs, projects, contemporary approaches and documentation as well as methods for the evaluation. The thesis also analyzes the main strategic documents related to the development of the monitored area through which the importace of development is confirmed. Especially in the area of tourism there is a potential area specific for such development. There are also included characteristics of the area, history and explanation of the specific municipalities. The usage of financial aids for the development of tourism is evaluated in the analysis of realized projects. Various projects in the field of tourism development in Horňácko are specialy evaluated with objectives of strategic documents and the usage of potential in the area. In the evaluation we find essential persistent problems which are confirmed by the content of the new LAG strategy for the next programming period from 2014 to 2020. There are researched further possibilities of financial aid for new programming period from several sources availible on different levels in the framework of ascertined facts.
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Materials for Supercapacitors
Dvořák, Petr ; Paidar,, Martin (referee) ; Trnková, Libuše (referee) ; Sedlaříková, Marie (advisor)
This dissertation deals with the electrode materials, liquid and gel electrolytes suitable for supercapacitors. In the field of electrode materials were investigated carbon materials based on carbon blacks, expanded and micronized graphite suitable for supercapacitors working on the principle electrochemical double layer. Another area which this thesis deals with are aprotic liquid electrolytes prepared from suitable types of salts and aprotic solvents. The last part is focused on the preparation and subsequent electrochemical characterization of gel polymer electrolytes in order to increase the ionic conductivity of these electrolytes.
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Preparation Techniques and Characterization of Electrodes with Nanostructured Surface
Hrdý, Radim ; Trnková, Libuše (referee) ; Janderka,, Pavel (referee) ; Hubálek, Jaromír (advisor)
Nowadays, nanostructures fixed on solid substrates and colloidal nanoparticles permeate through all areas of human life, in area of sensors and detection as well. This dissertation thesis deals with the fabrication of nanostructures on the surface of planar electrodes via self-ordered nanoporous template of aluminum trioxide. The nanofabrication, as one of many possible techniques, is used to increase the active surface area of electrodes by creating unique surface types with specific properties. These electrodes are very perspective in the applications, such as biomolecules electrochemical detection and measurement. The transformation of aluminum layer into non-conductive nanoporous template in the process of anodic oxidation is a fundamental technique employed to obtain the array of nanostructures in this thesis. The fabrication of high quality nanoporous membranes with narrow pore size distribution on various types of metallic multilayers is one of the key experimental parts in this work. Several problems associated with the production of the thin-film systems, including the dissolving the barrier oxide layer, are discussed and solved. Another part of this work deals with the use of nanoporous membrane as a template for the production of metallic nanostructures via electrochemical metal ions deposition directly into the pores. The obtained nanostructures as nanowires, nanorods or nanodots are characterized by the scanning electron microscopy and energy-dispersive or wavelength X-ray spectroscopy. The electrode surface, modified by gold nanostructures suitable for the detection of biomolecules, has been chosen for the electrochemical measurements, due to the gold biocompatibility. The nanostructured electrodes were characterized by electrochemical impedance spectroscopy and cyclic voltammetry. The effect of nanostructured surface geometrical parameters, including the size of the electrochemically active area, on the results of electrochemical measurements has been observed and compared to flat gold electrodes. Two model biomolecules, namely guanine and glutathione, have been chosen for the study of potential application of these nanostructures in biosensors.
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