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HPLC Determination of Lutein, Zeaxanthine and Betacarotene in Dietary Products
Dvořáková, Petra ; Šatínský, Dalibor (advisor) ; Chocholoušová Havlíková, Lucie (referee)
This rigorous thesis deals with modification of method for separation carotenoids lutein, betacarotene and zeaxanthin borrowed from diploma thesis (Optimization of chromatographic conditions for HPLC determination of chosen carotenoids, Petra Dvořáková, 2009). HPLC with VIS detection is the basic method. This method was modified by gradient elution for compressed time of analysis. Four ways of gradient elution were tested during optimization of new procedure. The second aim of this rigorous thesis is summary of extraction ways for carotenoids published in special literature and proposition of extraction procedures for carotenoids from dietary products. Extraction with organic solvents was used during searching for optimal way for extraction. Simple extraction with organic solvent was tested as basic method, but extraction with previous modification of sample (saponification or acidification of extraction medium) was tested too. In spite of testing of many various ways for extraction and many various organic solvents, there wasn't find optimal and universal extraction way.
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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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Chromatography method optimization for HPLC determination of carotenoids.
Dvořáková, Petra ; Šatínský, Dalibor (advisor) ; Solich, Petr (referee)
This thesis deals with searching for optimal conditions for determination of carotenoids lutein, betacarotene and zeaxanthin. High performance liquid chromatography - HPLC was used for determination. During searching for optimal conditions many various columns and mobile phases were tested. Primary information about carotenoids separation was obtained from scientific literature. There were tested both types of chromatography - normal phases chromatography and reversed phases chromatography. The most frequently tested columns were C18 columns from different producers. The biggest problem for HPLC determination and separation of these three substance were position isomers of lutein and zeaxanthin. Separation of these substances is relatively difficult and it wasn't completely solved in this thesis. In spite of it new metod for determination and separation of three carotenoids was developed. This method used isocratic elution at column Zorbax SB C18 (50 x 4,6 mm, 2 μm), UV detection at 450 nm, mobile phase of methylene chloride:hexan:acetonitrile (2,5:2,5:95), injected volume 1 μl and flow rate at 1 ml/min.
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The effectt of shrubs on establishment of woody plant species in grazed landscape
Wiesner, Pavel ; Vojta, Jaroslav (advisor) ; Brůna, Josef (referee)
My bachelor thesis is concerned about mechanisms that influence establishment and growth of woody plant species under grazing pressure in the temperate climate region. Based on literature sources it determines and explains individual mechanisms and attempts to merge them into a holistic view of the issues of reproduction, propagation and survival of trees and shrubs in the grazed landscape. In general, grazing affects the course of natural succession and under certain conditions helps to maintain shifting landscape mosaics. In addition, the effects of grazing are retroactively modified by the already existing vegetation mosaics. In this regard, existence of shrubs providing protection to seedlings and saplings against bad environmental conditions and against grazing pressure is important, as they help to change spatial heterogenity of vegetation and to establish the shifting mosaics mentioned above. As the spatial heterogenity and total diversity of vegetation can increase or decrease under influences of many factors, the bachelor thesis also pursues the importance of spatial distribution and intensity of grazing, different commonly grazed species and usual systems of grazing management. Keywords: grazing, associational resistance, cyclic succession, wood-pastures, spatial heterogenity of...
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Novel Approaches to the Application of Electrochemical Volatile Compounds Generation in Spectrometric Methods
Červený, Václav ; Rychlovský, Petr (advisor) ; Spěváčková, Věra (referee) ; Komárek, Josef (referee)
Various possibilities for the use of electrochemical generation of volatile compounds for the determination of trace and ultratrace quantities of elements using atomic absorption spectrometry and optical emission spectrometry, respectively, were studied in this work. The Thesis is divided into four thematic sections. Electrochemical cold mercury vapor generation is common to the first two parts. The third part is devoted to electrochemical generation of the volatile form of cadmium and the last part deals with the use of the electrochemical hydride generator as a derivatization unit for speciation analysis of arsenic compounds. The optimization of each individual determination was carried out including, for example, various designs of the generator of volatile compounds (forms) of the analyte, the changes in the design of the gas-liquid separator, optimization of the concentration and the flow rate of all the solutions and the carrier gas. However, the value of the electric current employed was the most important parameter. In the first section, the in-situ trapping system of the cold mercury vapor generated in the graphite furnace (with the inner surface covered with a gold foil) of the atomic absorption spectrometer was also designed and optimized. The absolute limit of detection, 80 pg, was...
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The Northern Lapwing ( Vanellus vanellus) -- a model species for research of precocial problems in Shorebirds ( Charadrii)
Kubelka, Vojtěch ; Šálek, Miroslav (advisor) ; Cepák, Jaroslav (referee)
Precociality has large energy demands on a freshly hatched chick which must start to feed itself and face environmental factors more than altricial nestlings. The Northern Lapwing (Vanellus vanellus) is a suitable model species for presenting the precocial problems of shorebirds (Charadrii), a typical precocial group of birds. A better understanding of the lapwing chick's problems in different habitats will deepen our knowledge about ecological constraints and adaptations of precocial shorebirds and, at the same time can be very helpful for determining the rules of effective conservation of endangered species. The chick size, growth, condition and survival are influenced by egg volume but also by the quality of the parents during the 35 day period that the chick needs to achieve fledging. A Lapwing chick's mortality is highest during the first 10 days of its life due to all of the further mentioned factors, which are even stronger in the critical and delicate period of the chick's life after hatching. Lapwing chicks forage non-selectively on the most abundant and available types of prey found on the soil surface, in soft mud or shallow water. Their diet consists of various types of invertebrates, particularly earthworms, beetles and other groups of insects. The proportion of particular food...
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Podmínky optimálního řazení dávek u dvou procesorů
Černý, Jan ; Pelikán, Jan (advisor) ; Černý, Michal (referee)
Práce se zabývá charakterizací flowshop problému ? problému optimálního řazení dávek u dvou procesorů a měla by posloužit jako zdroj informací o této problematice. Jsou zde zavedeny jednotlivé teorémy, obnoveny některé základní pojmy, používané při definování částečného uspořádání a vztahující se k analýze intervalové struktury. Dále jsou zde náhledy na dvě konkrétní intervalové struktury pro F2|prmu|Cmax problém a vyloženo několik postačujících podmínek optimality, začínající u částečné intervalové struktury a končící u obecných, celých případů.
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Crisis of the Swedish welfare state and its reforms in the 90s of the 20th century
Hes, Lukáš ; Vostrovská, Zdenka (advisor) ; Czesaný, Slavoj (referee)
This master thesis explores what were the causes of falling behind of the Swedish economy during the 70s and 80s of the 20th century. In addition, it deals with the reforms that Sweden has implemented during 90's. Theoretical input is engaged in development of economy and society and focuses on the period of the 30s, which was crucial for further development and in which laid the foundation for later growth. In the analytical part are explored the causes of the economic slowdown. This led to the gradual decline of economic level and a slump in international rankings. Analysis of the reforms carried out during the 90s of the 20th century provides guidance for all countries which want to optimize the allocation of resources in the economy and are trying to accelerate economic growth.
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