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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.
101

Analýza mastných kyselin ve vybraných tkáních prasat po aplikaci rybího tuku do krmné dávky

Hrazdilová, Zlata January 2017 (has links)
Literar review of thesis is focused on clasification of lipids, fatty acids characteristics, particularly polyunsaturated acids n3 alpha linolenic, eicosapentaenoic and docosahexaenoic acid; and polyunsaturated acids n6. There is description of metabolic reactions. Degradation by beta oxidation, biosynthesis and conversion to eicosanoids. Function and effect of eicosanoids to organism and health, nutritional representation of this fatty acids, fortification of food sources, feed in interest of improvement health condition and functional foods producing. The practical part is focused on fatty acids analysis in muscular, liver and adipose tissue of pigs after feed fortification by 2,5 % fish oil and 2,5 % palm oil in the diet. Lyofilizated samples were derivatized and determinated by gas chromatography method. Results were evaluated by statistics program.
102

Zatížení půd České republiky estery kyseliny ftalové

Picková, Tereza January 2017 (has links)
The thesis on the topic Soil pollution by phthalic acid esters in Czech Republic solves the problem of soil pollution by dibutyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP). This thesis joined the annual monitoring conducted by Central Control and Testing Institute of Agriculture. The monitoring of contaminants was carried in twelve regions of the Czech Republic. The samples do represent different types of culture farmland. They were formed by arable land, permanent grassland and hop-garden. Before the analysis, the samples were extracted with acetone-hexane mixture with 1:1 ratio, and ultrasound. Samples were analyzed by liquid chromatography with UV detection. The measured concentrations for the year 2016 ranged in DBP from 0.07 to 0.21 mg.kg-1 dry weight, at DEHP from 0.19 to 1.08 mg.kg-1 dry weight, esters together from 0.13 to 0.65 mg.kg-1.
103

Biologicky aktivní látky v sóji

Sedláčková, Eliška January 2017 (has links)
Submitted master thesis summarizes current knowledge about biologically active sub-stances contained in soybeans (Glycine max L. Merrill). Mainly deals with problematics of isoflavones, mechanism of origin and effects on human healht. Then the theoretical part summarizes mainly modern instrumental technics using for determination of isofla-vones. The experimantal part is concentrated on identification of soy isoflavones gathered from eight varieties (Brunensis, Bohemians, Naya, Moravians, Silesia, Toutatis, Korus, Kofu) of soybeans cultivated in Czech Republic. For detection of free, conjugated and total isoflavones was used high performance liquid chromatography with mass spectro-meter (LC-MS/MS)
104

Plynová chromatografie mastných kyselin ve vybraných živočišných tkáních

Drábková, Michaela January 2017 (has links)
The aim of this diploma thesis was to determine, using gas chromatography, fatty acids in selected animal tissues. Specifically, the muscle, liver, pulmonary and adipose tissues were observed. A total of 32 piglets were divided into two groups with 16 pigs in each group. During 75 days of fattening, each group was given a feed mixture differing in the type of oil added. The experimental group was fed a basic feed mixture with the addition of 2,5 % fish oil, whilst the control group with the addition of 2,5 % palm oil. The animals were fed ad libitum. After slaughter, samples of selected tissues were taken and the process of lyophilisation was carried out. Using extraction method according to Hara, Radin (1978), lipids from lyophilized tissue samples were extracted. Fatty acids present within these lipids were then transformed into more volatile fatty acid methyl esters by the process of derivatization. These were then determined by gas chromatography and the results were statistically evaluated. The effect of fish oil in the feed mixture resulted in the increase of PUFA n-3 (P < 0.01) in all of the tested tissues. The addition of palm oil, on the other hand, had an effect on the content (P < 0.05) of SFA, MUFA in the tested tissues.
105

Kvantitativní analýza inhibitorů tyrozinkinázy metodou kapalinové chromatografie s hmotnostní detekcí / Quantitative analysis of tyrosine kinase inhibitors employing liquid chromatography with mass spectrometry detection

Maier, Jan January 2021 (has links)
The submitted thesis is devoted to the quantitative analysis of tyrosine kinase inhibitors, specifically imatinib and nilotinib, by liquid chromatography-mass spectrometry method. The main purpose of developing this new method of analysis at the Department of Clinical Biochemistry and Diagnostics at the University Hospital in Hradec Králové was measuring and monitoring serum or plasma concentration levels of these drugs in patients with chronic myeloid leukemia, less often in patients with gastrointestinal stromal tumour. The main task during the elaboration of the thesis was to fully optimize and validate the method. Previously, this method for the analysis of tyrosine kinase inhibitors was routinely performed here by high-performance liquid chromatography with spectrophotometric (UV) detection. As part of the modernization of laboratory technology, they started to use high-performance liquid chromatography with mass spectrometry at the workplace. The analytes with their internal standards were obtained by a liquid-liquid extraction process. Then, samples were separated on a C18 reverse phase column using isocratic elution. Subsequently, both analytes were detected by a triple quadrupole tandem mass spectrometer with ESI ion source in a positive mode. As a part of the method validation was to...
106

Analýza vybraných léčiv pomocí TLC chromatografiejako námět pro laboratorní cvičení / Analysis of sellected drugs with the use of TLC as a topic of laboratory courses

Menzel, Petr January 2018 (has links)
The paper aims to mediate thin film chromatography analysis by means of drugs commonly found in households (analgesic-antipyretics) to secondary school and grammar students, or to college students. For this purpose, laboratory tasks have been designed to cover all levels of the Bloom pyramid so that the educational potential is as high as possible. This is closely related to the topic of drug expiration and treatment. Pupils and students should take on both the competences of knowledge, skills, and attitudes. Keywords: thin layer chromatography; TLC; chromatography in education; educational experiment; expiratory medication; drug handling; analgesic- antipyretics, acetylsalicylic acid, paracetamol
107

Optimalizace podmínek a postupů při získávání bylinných extraktů. / Optimization of conditions and procedures for plant extraction.

SMUTNÍKOVÁ, Kateřina January 2012 (has links)
The thesis deals with the content of selected phenolic compounds in some species of the genus Amaranthus, in black elderberry (Sambucus nigra L.) and buckwheat (Fagopyrum esculentum M.). Phenolic compounds are a group of natural compounds exclusively vegetable character. Flavonoids represent only one group of phenolic compounds. Flavonoids show many positive biological effects, in particular act as antioxidants. Natural flavonoids may cause to prevent from coronary- heard diseases and other diseases associated with older age. In recent years the increased attention is paid to flavonoid investigation due to its biological effects. For the determination of phenolic substances there were used two independent analytical methods. There are the high-performance liquid chromatography (HPLC) and micellar electrokinetic capillary chromatography (MECC). The MECC method was used for determination rutin and free quercetin. The highest content of rutin was found in leaves of buckwheat (76,400 mg/kg of dry weight) and the lowest content of rutin was determined in buckwheat hulls. The highest content of rutin was observed in teas from buckwheat leaves and inflorescence. This amount of rutin corresponds with rutin content in more than two pills of Ascorutin (the most favourite flavonoid medicament in the Czech Republic) The HPLC method was used for quantitative determination of phenolic acids. The content of free quercetin was monitored in all samples. No free quercetin was found both in plant material and in samples of teas. The ethanolic extract from the elderberry inflorescence didn´t contain any free quercetin. Free quercetin wasn?t found in any further samples of teas, which were prepared by described methods.
108

Izolace čistých aminokyselin z pšeničných otrub / Isolation of pure aminoacids from wheat bran

Sloupová, Klára January 2021 (has links)
Wheat bran is a promising material containing a wide range of useful components, including proteins. In addition, it is produced in significant volumes. Currently, wheat bran is used for the production of energy by combustion and for feed purposes. Gradually, new methods of valorization of this material are being sought. One of the possibilities of using wheat bran is the isolation of proteins, hydrolysis, and separation of selected amino acids. This diploma thesis deals with this issue, it is focused on the recovery of arginine and leucine from a protein isolate. Proteins were extracted from wheat bran by changing the pH. Thanks to the subsequent lyophilization a protein isolate was gained. Prior to hydrolysis of the resulting isolate, a stability test of arginine and leucine amino acid standards was first performed, to which various hydrolysis methods were applied. Acid hydrolysis using a mineralizer, which was applied to the protein isolate, was proved to be the most effective. This was followed by the derivatization of the hydrolysates with OPA and analysis of the resulting hydrolysates by high-performance liquid chromatography with UV-VIS detection. Then, suitable adsorption and desorption conditions were optimized. It was found that the time dependence does not affect the amount of adsorbed material on the sorbent. Therefore, an application time of 15 minutes was chosen. While optimizing the amount of used standard, it was found that the optimal weight was 0.25 g of sorbent. The selected conditions were applied to the protein hydrolyzate. Two fractions were obtained by the separation of selected amino acids due to the change in the pH of the citrate buffer. After the application of this procedure, 0.26 g of arginine and 0.82 g of leucine were obtained from one kilogram after evaporation. From evaporation two, 1.01 g of arginine and 0.25 g of leucine were obtained after evaporation.
109

Analýza hlavních sacharidů vína / Analysis of main wine saccharides

Horáková, Hana January 2009 (has links)
This diploma thesis deals with determination of carbohydrates in wine. Theoretical part attends to production of wine from grape to treatment and training of wine. It refers saccharides in wine, especially glucose and fructose. The study provides an overview of the available sources concerning the possibilities of determination of carbohydrates in wine by chromatographic methods and Skalar automated chemistry analyser. The study shortly refers simple analytical methods for determination of wine saccharides. The experimental part based on this search deals with analysis of saccharides by high performance liquid chromatography with refractive index detector and UV detector on aminoalkyl column and determination of reducting sugars by Skalar automated chemistry analyser. Finally, the results of these methods were compared.
110

Stanovení musk sloučenin v biotických matricích / Determination of musk compounds in biotic matrices

Soukupová, Alena January 2011 (has links)
This diploma thesis deals with actual issues of the contamination in the environment with synthetic fragrances. Musk compounds are infiltrated to many environmental components (especially an aquatic ecosystem) because of their biological persistence and the ability of accumulation. This diploma thesis is focused on the selection and the optimization of method for the determination of musk compounds in real biotic matrices (fish). The isolation of analytes was realized by PSE method and the purification of extract was realized by the method of the adsorption column chromatography. Identification and quantification of individual musk compounds was carried out by GC-MS. In conclusion were results and the contamination of fish from the river Svratka disscissed and evaluated. These fish were caught at the inflow and at the outflow of the wastewater treatment plant.

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