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Bioassay Guided Separation of Metabolites of the Selected Plant Species - Evolvulus Alsinoides
Červenka, František ; Jahodář, Luděk (advisor) ; Grančai, Daniel (referee) ; Patočka, Jiří (referee)
9. SUMMARY 134 This experimental work deals with pharmaco-botanical evaluation of the aerial part of taxon Evolvulus alsinoides L. The plant is a component of formulations with nootropic and adaptogenic activity. A subject of the investigation was a dried herb of the plant, which is of Indian origin. The aim of this work was to extend the knowledge about compounds of the taxon, to evaluate biological activity of the fractions, isolated substances and to determine characteristic metabolites of the plant. In the first part of the project the crude extract of the plant E. alsinoides was prepared by percolation of 8.8 kg of herb with 95% ethanol. The extract was partitioned into three extracts by extracting by two solvents of different polarity (petroleum ether, ether). The first fraction of weight 92.1 g was obtained by extracting of methanolic solution of crude extract with petroleum ether. The second fraction of weight 69.7 g was obtained by extracting of water solution of the crude extract with ether. The remaining solvent was evaporated from the crude extract and this one represented the third part - polar residue, yield 231 g. The fractions were processed by the methods of column chromatography (CC). The bioassay-guided separation of selected parts of extract (test of acute toxicity, fototoxicity,...
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Preconcentration of Trace Analytes on Modified Sorbents and their Determination on Waters
Holubová, Zuzana ; Čelechovská, Olga (referee) ; Holoubek,, Ivan (referee) ; Otruba,, Vítězslav (referee) ; Sommer, Lumír (advisor)
The work has been focused on the preconcentration techniques for determination of 9Be, 51V, 59Co, 60Ni, 89Y, 111Cd, 208Pb, 232Th and 238U on the modified sorbents, all measurements were performed on ICP-MS. The instrument setup was optimized. The solution of internal standard (200 µg•l-1) was used during all measurements. The internal standard were chosen as follows: 6Li for 9Be, 45Sc (51V), 72Ge (59Co, 60Ni, 89Y), 103Rh (111Cd), 209Bi (206Pb, 207Pb, 208Pb, 232Th and 238U). Another parameters such as influence of mineral acids (HCl, HNO3), surfactant (Septonex®, Zephyramin, Ajatin, Brij 35 and Sodium dodecyl sulphate) and organic reagents (Ammonium pyrrolidinedithiocarbamate, 8-Hydroxyquinoline-5-sulphonic acid, 1,2-Dihydroxyanthraquinone-3-sulphonic acid and 4-(2-Pyridylazo)resorcinol) and the effect of some matrix components on intensity of instrument signal determination was investigated. For preconcentration polar Silicagel and modified nonpolar Silicagels (Silicagel-C18, C8 nad Phenyl) were used. Another experimantal part was dedicated to preconcentration on nonpolar Amberlite XAD-16 and Strata SDB-L and intermediately polar sorbent Amberlite XAD-7. Recoveries of sorption process were observed in the presence of all testing types of surfactants in certified concentration 5•10-4 mol•l-1. Surfactants were always applied in the conditioning step. The suitable combinations of surfactant and organic reagent were tested for increasing of recoveries of analytes. Testing organic reagents were added in five times mass excess againts concentration of analytes, the concentration of the organic reagents was 900 µg•l-1. The organic reagent was always added to the solution for preconcentration before this solution was led on the sorbent. The composition and a necessary volume of elution mixture for quantitative elution were tested, too. Only one sorbent was chosen from each group of sorbents with similar properties. The chosen sorbent showed the best recoveries in majority of target analytes. The highest recoveries from silica-group was reached for Silicagel-C18, from nonpolar Amberlite was chosen Strata SDB-L and intermediately polar Amberlite XAD-7. The influence of some matrix components (anionts and cations) on recoveries of analytes was investigated for chosen sorbent. The optimized process was applied on real samples of nature water and industry water. In experimental part all analytes are marked as specific izotopes, which were measured by ICP-MS. Of course, all izotopes of analytes undergo preconcentration techniques.
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Evoluce mechanismů transportu auxinu.
Skokan, Roman ; Petrášek, Jan (advisor) ; Cvrčková, Fatima (referee)
Auxin, the longest studied phytohormone, is distinguished from other phytohormones by its unique directional, so-called polar transport. This feature helps to facilitate the broad range of auxin action at all stages of plant development. The polar auxin transport has been evolving together with plant lineages. By studying the mechanisms of auxin transport, biosynthesis, metabolism and particularly signaling we can perhaps better elucidate many milestones of plant evolution, such as complex multicellularity or transition to land. This bachelor thesis summarizes the available data and gives a basic overview of auxin-related characteristics. As far as we know, the advanced mechanisms of auxin transport and signaling known from land plants are probably not very ancient and are absent in various algae. Auxin biosynthesis, however, is rather common and a lot of green algae contain orthologs of important biosynthetic enzymes from land plants. Based on the available data it seems that a complete auxin signalling pathway coupled with proteasomal degradation and affecting gene expression is not present in algae. The polar auxin transport, so far with the earliest evidence from moss sporophytes, was recently found in the gametophytic thallus of stonewort (Chara) from a green algal clade Streptophyta, which is...
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Zirconia-based and Chiral Stationary Phases in Pharmaceutical Analysis
Kučera, Radim ; Sochor, Jaroslav (advisor) ; Blešová, Marie (referee) ; Pospíšilová, Marie (referee)
Disertační práce Summary High performance liquid chromatography achieved during its existence enormous boom. Modern, PC controlled and user-friendly chromatographic devices allow performing a number of tens analyses on one apparatus daily. There is possible to analyse wide spectrum of compounds from non-polar to polar and from low molecular to high molecular analytes. Appropriate choice of chromatographic column, mobile phase and detection technique makes the analysis of complicated mixtures possible and allow obtaining both qualitative and quantitative information. HPLC is due to these characteristics utilized not only in the field of pharmacy but also in other areas e.g. biology, medicine, industry, environment monitoring and quality control of various products. Separation column is the most important part of the chromatographic system. The availability of stable, high performance chromatographic phases is the essential requirement for the development of a rugged and reproducible method. Nowadays, most HPLC separations have been done in the reversed-phase mode on the silica-based columns. This phenomenon is due to many positive properties of silica - mechanical strength, well mastered manufacture of silica particles, easy modification of silica surface, compatibility with water rich mobile phases etc. The...
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The climate of Norway as a factor influencing tourism
Lhotka, Ondřej ; Míková, Taťána (referee) ; Sládek, Ivan (advisor)
This bachelor's work describes the elements of Norwegian climate, which have immediate influence on human activities in the nature. This work insist on the regime of sunshine in reference to the astronomical and meteorological factors. The duration of daylight and the presence of the polar day and the polar night is described for several places in Norway. The sunny and dark periods are defined for Oslo and Tromsø, the amount of cloud cover throught the year is illustrated, too. The temperature conditions are characterised throught the use of the map with mean annual temperature and the tables with mean month temperatures, mean month minimum temperatures and extreme temperatures. The wind regime is described in the table and illustrated throught the use of five wind roses. After it there is a map with mean annual precipitation and the tables with mean month precipitatation and the amount of precipitatation-days for several places. The height of the snow cover throught the year is described, too. At the end there is a suggestion about the content of "climatic guidebook" and a recommendation of proper time for visiting Norway.
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HPLC separation of p-aminophenol, paracetamol, caffeine and propyphenazone on polar stacionary phase.
Maroušková, Alena ; Sklenářová, Hana (referee) ; Šatínský, Dalibor (advisor)
This thesis deals with finding optimal chromatographic conditions for a separation of p- aminophenol, paracetamol, caffeine and propyphenazon by HPLC. These analytes have different polarity and acidobazic properties. The application of traditional octadecylsilane stationary phases for their simultaneous determination is problematical. The PEG column have proved to be suitable for an efficient separation of the analytes with different polarities, i.e. with different chromatographic behavior. The resulting method brings shortening of analysis time, which is important for analysis of big series . Within the optimization of chromatographic conditions: a wide range of mobile phases has been tested (various organic solvents, various ratio of organic components to water phase components) a various level of acidity of the mobile phase has been tested ranging from 4 to 7 pH units various buffers have been tested behavior of the analytes has been tested under an enhanced temperature two PEG columns with different lengths have been tested Optimal chromatographic conditions for a separation of the analytes mentioned above, as well as the fulfillment of requirements for simplicity, analysis time and high degree of reliability have been found. The final chromatographic conditions: Stationary phase:...
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Implementation of geodetic works within stakeout of landscaping
KLEMPA, Petr
Bachelor thesis "Implementation of geodetic works within stakeout of landscaping" is focused on the description of the process of geodetic methods and their subsequent implementation in the terrain, specifically in the area of Vitín. Stakeout took place on the basis of a valid digital cadastral maps. There was staked out eight points by polar method on the border of the parcel 1130/8 in cadastral area Vitín. There was staked out eighteen points by GNSS method on the border of the parcels 810/5 and 760/11. The aim of the study is to compare and evaluate of used geodetic methods in terms of accuracy, time constraints, etc.
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Evaluation of properties of new HILIC stationary phases for pteridins using UHPLC-FD method
Kaufmannová, Iva ; Nováková, Lucie (advisor) ; Šatínský, Dalibor (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of analytical chemistry Candidate: Iva Kaufmannová Supervisor: PharmDr. Lucie Nováková, Ph.D. Title of Doctoral Thesis: Evaluation of properties of new HILIC stationary phases for pteridins using UHPLC-FD method The subject of this thesis was to evaluate the characteristics of three new types of HILIC stationary phases for the identification and quantification of biologically active substances biopterin, neopterin, dihydrobiopterin and dihydroneopterin by UHPLC with fluorescence detection. Neopterin is used as a marker of immune system activation and inflammatory diseases. Its early detection in urine or plasma may indicate a pathological immune activity. Elevated concentration of neopterin is described in viral or bacterial diseases, in autoimmune diseases in HIV infection or in malignant tumors. 7,8 - dihydroneopterin is able to prevent proteins and lipoproteins from oxidative damage. Hydrophilic Interaction Liquid Chromatography (HILIC) is a chromatographic method that can be used to improve retention of very polar compounds. It uses a polar stationary phase and mobile phase containing a certain amount of water and polar solvents. UHPLC is the most advanced separation technology to develop a pressure of about 100 MPa....
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