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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Sója a její využití / Soja and its use

TVRZICKÁ, Nela January 2016 (has links)
The diploma thesis presents the results of studies on the awareness of women aged 18 to 30 years about soya. The theoretical part deals with the characteristics of soya, describes its varieties, cultivation and its composition. There is also described the ways we can use soy and here you will find a list of food soya products and their descriptions. In the last chapter of the theoretical part is defined, what is the effect of soya on human health. The practical part evaluates poll thematized awareness of the soybean and its use. It identifies the general knowledge about the abundance of legumes and its representation in the diet of female respondents. Alternatively, in what form . The analysis is based on quantitative research, which was conducted through an anonymous questionnaire. Most often like interviews. Obtained data are processed in graphical and tabular form.
22

Studium molekulární organizace systému cytochromu P450 pomocí fotoaktivovatelných proteinů / Study of molecular organization of cytochrome P450 system using photoactivatable proteins

Dědič, Jan January 2015 (has links)
The cytochrome P450 system plays an important role in metabolism of endogenous compounds and xenobiotics. This system consists of cytochrome P450, NADPH:cytochrome P450 oxidoreductase (CPR), cytochrome b5 and NADH:cytochrome b5 reductase (CYB5R3). Explanation of protein-protein interactions among these reaction partners is essential for understanding the function of the entire system. Covalent cross-linking is a favorable method for studying these interactions. In this work a photo-activatable analogue of amino acid L-methionine (L-photo-methionine) was used as a cross-linking agent. This work is focused on the organic synthesis of L-photo-methionine, expression and isolation of CPR and CYB5R3 as photoactivable proteins containing incorporated L-photo-methionine. Auxotrophic strain of E.coli B834 (DE3) and minimal media were used for the expression. CYB5R3 with incorporated L-photo-methionine was successfully expressed and isolated. The extent of L-photo-methionine incorporation was verified by mass spectrometry. Furthermore, the photo-initiated cross-linking of CYB5R3 with cytochrome b5 was tested. Key words: photolabile amino acid, protein expression, synthesis
23

Vypracování a zavedení metodiky na stanovení osových proteinů / Elaboration and introduction of the method for determination of some proteins

Hruzík, Ondřej January 2008 (has links)
Core protein of aggrecan has a significant share on the correct function of articular cartilage. Its lack or structural failure could be the reason for the disfunction of the cartilage. The culture of chondrocytes taken from a pork articular cartilage was used for the study of aggrecan production. The monolayer culture method offers the model system which has enabled us to watch the aggrecan production into growth medium. The aggrecan synthesis was stimulated in the media with addition of L-methionin, L-serin and sodium selenite pentahydrate. Methionin and serin are antecedents of sulphur amino acid of cysteine, whose role is incredibly important for the correct function of core protein. Growth media and chondrocytes were analysed with the help of the automatic amino acids analyzer unit after acid or oxidative hydrolysis. The analyse established the amino acid representation. The main attention was paid to cysteine. The changing concentrations of this amino acid were showing if the antecedents in the addition are used for its production and, therefore, if it is possible to stimulate the production of core protein with these antecedents. The results are discussed in the conclusion of this thesis. The next step should be the detection of the concentration of synthesized aggrecan by the immunological method. Presently this method is very expensive. Therefore, the method of setting the core protein of aggrecan with the help of suitable amino acid was used for the first tests.
24

Chirální separace nově syntetizovaných aminokyselin metodou HPLC / Chiral HPLC separation of newly synthesized amino acids

Kučerová, Gabriela January 2013 (has links)
The aim of this work was to develop and to optimize HPLC method for enantioseparation of newly synthesized derivatives of amino acids. The set of these analytes contained four N- blocked derivatives of D,L-Phenylalanine, three N-unblocked derivatives of D,L- Phenylalanine, , one methylated derivative of D,L-Tyrosine and D,L-Tyrosine. Two separation modes i.e. reversed phase and polar-organic modes and two columns i.e. Chirobiotic® T and Chirobiotic® T2 were used. Chiral stationary phases of these columns were composed of macrocyclic antibiotic teicoplanin coated on silica gel support. As mobile phases in revesed phase mode, methanol and acetate buffer were used with Chirobiotic® T column. The most suitable concentration were 20 mM and the most suitable pH value were 4.00. Under the above mentioned conditions eight analytes of ten were separated and the optimal conditions were found. Polar-organic mode and Chirobiotic® T column were suitable only for enantioseparation of three N-blocked derivatives of D,L- Phenylalanine. Mobile phases were composed of methanol with small additions of triethylamine and acetic acid. Chirobiotic® T2 column in reversed phase mode was not suitable for tested set of analytes. Only partial separation of D,L-Tyrosine derivative and one N-unblocked D,L-Phenylalanine...
25

Agregace aminokyselin a podobných molekul v přítomnosti fosfolipidové monovrstvy / Clustering of aqueous aminoacids and similar molecules in the presence of phospholipid monolayers

Kukharchuk, Alexandra January 2016 (has links)
Amino acid phenylalanine plays a key role in numerous biological processes and is also involved in amyloid fibril diseases. The aim of the thesis is to deepen our understanding of its behavior and partitioning at interfaces, and to investigate its clustering. Classical atomistic molecular dynamics simulations were performed for phenylalanine and three other aromatic molecules which chemical structure is derived from it - phenylglycine, phenylacetic acid and tyrosine. Molecules are simulated at both water-air and at water-DPPC-air interfaces. Phenylalanine, phenylglycine and phenylacetic acid demonstrate surface activity at the water-air interface, whereas tyrosine is not surface active. All molecules interact with the lipid monolayer at the water-DPPC-air interface but only phenylalanine penetrates deep into the monolayer. Formation of transient clusters is observed in the interfacial regions, mostly for phenylalanine. Powered by TCPDF (www.tcpdf.org)
26

Sulfobutylether-β-cyklodextrin jako chirální selektor pro separace aminokyselin a dipeptidů v HPLC / Sulfobutylether-β-cyclodextrin as a chiral selector for separation of amino acids and dipeptides in HPLC

Procházková, Hana January 2017 (has links)
The main aim of this work was to prepare and characterize a new chiral stationary phase (CSP). The CSP was prepared by dynamic coating of sulfobutylether- β-cyclodextrin (SBE-β-CD) on a strong anion-exchange stationary phase (SP). The selectivity and stability of the newly prepared CSP were tested on the sets of chiral and achiral analytes. The next separation system used was composed of C18 SP with the addition of SBE-β-CD as a chiral selector into the mobile phase. The set of chiral analytes contained amino acids phenylalanin, tyrosine, tryptophan, their derivatives and dipeptides glycine-DL-tryptophan and glycine-DL- phenylalanin. Four groups of mixtures of blocked and unblocked dipeptide isomers were tested for achiral separations. Dipeptides used for the mixtures had the same molecular formula but the sequence of amino acids was reversed. Measurements were carried out in reversed phase separation mode and hydrophilic interaction liquid chromatography. Mobile phases composed of methanol as an organic modifier and four different aqueous parts: (i) deionized water, (ii) aqueous solution of formic acid (pH 2.10), (iii) 20mM ammonium acetate buffer (pH 4.70) and (iv) 10mM ammonium acetate buffer (pH 8.80) in various volume ratios. Newly prepared SBE-β-CD CSP was more suitable for separations of...
27

Experimentální studium chemické evoluce biomolekul v podmínkách rané Země / Experimental study of chemical evolution of biomolecules under early Earth conditions

Knížek, Antonín January 2018 (has links)
Origin of life is a still-enduring gap in human knowledge. This work is focused on revealing of several pieces of this puzzle. State of the art scenarios of biomolecules synthesis under prebiotic conditions are presented and discussed. This thesis presents our recent experiments suggesting a novel idea that neutral planetary atmosphere containing a mixture of neutral volcanic-type gasses (CO2, N2, H2O) can be converted over acidic mineral catalysts upon irradiation by a soft UV-radiation into a relatively reactive mixture of reducing gases (CH4, CO), which can be further reprocessed by high-energy chemistry. The resulting mixture (CH4, CO + N2) represents a common reducing atmosphere related e.g. to the chemistry of Titan, the largest moon of Saturn, as well as a possible representation of the secondary atmosphere of our planet. Also, photocatalytic reduction of CO2-rich atmosphere can explain the abiotic origin of methane on current Mars or other terrestrial planets. In our subsequent experiments, corresponding equimolar model mixture of CH4 : CO : N2 in presence of water vapour was subjected to reprocessing by high-power laser plasma simulating an asteroid impact - one of a series of impact events which the young Earth experienced during the first 600 million years of her history. Upon delivery...
28

Elektroforéza v krátkých kapilárách / Electrophoresis in short capillaries

Podhorná, Petra January 2011 (has links)
The laboratory-made apparatus for electrophoretic separations in short capillaries has been tested. The basic functions of the apparatus (separation efficiency, resolution, migration time) have been tested using mixture of K+ and Na+ ions. The model mixture of basic amino-acids (arginine, lysine, histidine and its derivatives, 3-methylhistidine and 1-methylhistidine) has also been separated and detected using contactless conductometric detector. Histidine in real sample of urine has also been determined. Keywords: capillary electrophoresis, short capillary, alkaline aminoacids
29

Nové metody přípravy protonizovaných aminokyselin a jejich interakce s polyelektrolyty / New methods of protonated aminoacids preparation and their interactions with polyelectrolytes

Trojan, Martin January 2012 (has links)
This Master thesis investigates the interaction between the polysaccharide sodium hyaluronate (HA) and some amphiphilic molecules. It is known that the presence of the carboxylic group on HA and the aminogroup on the amphiphiles leads to electrostatic interaction between these two compounds. This supposal offers the possibility to physically modify HA and use it as a new type of a carrier of bioactive compounds, for example medicals. However, successful carrier of bioactive compound has to resist a certain value of ionic strength. The high-molecular weights HA (1.75MDa) and amphiphile lysine were chosen for the study of the influence of ionic strength on the system HA – amphiphile. Our results show that system HA – amphiphile system is suppressed even by low concentrate solution of electrolyte. Therefore the system was reinforced by protonation of the aminoacid. The results show, that the interactions were reinforced, nevertheless negative influence of chlorine anions had to be eliminated by lyophilization. The solutions with strengthened system HA – amphiphile were used for the research of ionic strength influence. The amphiphiles lysine, 6 - aminocaproic acid and arginine were selected for this study. The interactions were investigated by means of reometry and conductometry.
30

Mohou být esenciální aminokyseliny považovány za chelátory mědi? / Can essential amino acids be considered as copper chelators?

Holotíková, Nikola January 2021 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany Candidate: Nikola Holotíková Supervisor: PharmDr. Jana Karlíčková, Ph.D. Title of Thesis: Can essential amino acids be considered as copper chelators? Copper is a trace element playing an important role in the human organism. Copper levels in the body have to be carefully controlled because disruption of copper homeostasis can cause oxidative damage which may lead to various pathologies. Chelation of copper can potentially be used as a therapeutic tool. Medical chelators should ideally mimic chelators, especially peptides and proteins which are important for regulation of copper homeostasis. Their structure is formed by amino acids linked by peptide bonds. For this reason, the study is focused on selected amino acids. Proteinogenic amino acids are classified into essential and nonessential. Essential amino acids must be obtained from the diet. The aim of this study was to compare the copper chelation and reduction activity of essential amino acids L-histidine and L-methionine, and nonessential amino acids L-cysteine, its dimer L-cystine, L-aspartic acid and L-glutamic acid. Also a L-cysteine-derived compound, N-acetylcysteine, was tested. All of them were tested using spectrophotometric methods at pHs which...

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