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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.
11

Vliv kadmia na oxidační stres u rostlin / The effect of cadmium on oxidative stress in plants

Zemanová, Veronika January 2015 (has links)
The two ecotypes of Noccaea caerulescens originating from two differently contaminated sites (Redlschlag, Austria; Ganges, France), N. praecox (Mežica, Slovenia), Arabidopsis halleri and Spinacia oleracea were studied to compare Cd accumulation and tolerance. After 30, 60, 90 and 120 days of cultivation in Cd contaminated soil (30, 60 and 90 mg Cd/kg soil) for hyperaccumulators and 25, 40, 55 and 75 days of cultivation in Cd contaminated soil (30, 60 and 90 mg Cd/kg soil) for spinach gas-exchange parameters (net photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO2 concentration), fatty acids, macro- and microelements were determined as well as N utilization by plants. Noccaea species and A. halleri showed similar changes in yield of biomass, Cd content and total content of amino acids. These species confirmed differences in the profile and contents of individual free amino acids. The comparison between Noccaea species showed that Cd stress resulted in similar changes of gas-exchange parameters. Contrasting responses of plants to Cd contamination were confirmed in macro- and microelements contents, fatty acids and amino acids metabolism. Spinach showed contrasting response to cadmium compared to hyperaccumulators, especially in profile of free amino acids and fatty acids.
12

Obsah biogenních aminů v potravinách

Smělá, Dana January 2004 (has links)
No description available.
13

Biologicky přístupné aminokyseliny v půdách vybraných ekosystémů

Hromádko, Ladislav January 2012 (has links)
No description available.
14

Mikroorganismy s dekarboxylázovou aktivitou z mléka a mléčných výrobků

Hůlová, Michaela January 2013 (has links)
This thesis deals with bacteria that are capable decarboxylase one or more amino acids and thus contribute to the formation of biogenic amines. The aim of this work was to characterize the bacteria with decarboxylase activitthe Escherichia coli, Bacillus, Lactobacillus, Enterococcus isolated from milk and dairy products. Microorganisms were inoculated into tubes with diagnostic medium. To test was used seven amino acids. Incubation tubes conducted at 6, 25, 30 and 37 ° C for 10 days during which the color change was monitored. The tested isolates of Escherichia coli were detected decarboxylase activity, especially for tyrosine and ornithine. The bacterium Bacillus licheniformis was found decarboxylase activity, especially on tyrosine. The bacteria Lactobacillus isolates tested were shown the strongest decarboxylase activity especially for arginine. The bacteria Enterococcus was demonstrated the strongest decarboxylase activity especially for arginine. Furthermore, the observed production of carbon dioxide and formation of biogenic amines contaminating microorganisms in cow's and goat's curd.
15

Proteiny ve výživě člověka

Fialová, Lucie January 2014 (has links)
This thesis describes the issues related to proteins in human nutrition. It deals with their specific functions in the human body, their structure and the recommended daily intake, and the consequences of either a deficiency or an excess of protein in human nutrition. For this thesis, the work focused on various food sources and their nutritional value, any positive or negative effects on human health, and their availability to consumers. Two different sources were used to determine the preferences and consumption of proteins from either animal or vegetable origins. Information was gathered from public sources, as well as a questionnaire that was given to randomly selected individuals.
16

Vyhodnocení obsahu aminokyselin v hovězím mase býků českého strakatého plemene

Šmachová, Monika January 2015 (has links)
The aim of the thesis named: "Evaluation of amino acid content in beef meat of Czech Fleckvieh bulls" was to evaluate the dependence of selected factors on the quality para-meters of beef, but primarily on the content of free amino acids. Amino acids are among the most important indicators of the nutritional quality of meat. The influence of slaughter age (520 - 540 days and 640 - 760 days) and the effect of carcass weight (220 - 300 kg, 301 - 350 kg and 351 - 500 kg) was analysed, both these indicators have a demonstrable effect on meat quality. In the case of essential free amino acid, the most represented was leucine, the amount of leucine was highest in animals in older and heavier weight categories. Furthermore, an effect of net gain (g.day-1) was observed, in this case the animals were categorized as follows: 437 - 550 g.day-1, 551 - 600 g.day-1 and 601 - 880 g.day-1 . Last factor whose effect was observed in relation to the quality of the meat was genotyping bulls in order to pro-ve the presence or absence of leptin genotype allele called "T".
17

Vliv vybraných stanovištních faktorů na proteolytickou aktivitu lesních půd s důrazem na organické a anorganické látky

Holík, Ladislav January 2017 (has links)
PhD thesis focuses on soil biochemistry, namely the effects of organic and inorganic substances on proteolytic ktivity in forest soils. The thesis is composed of several impacted journal articles and two manuscripts. Selected organic compounds feature L- and D-tartaric acid, phenolics, proteinogenic and non-proteinogenic amino acids, auxins and cytokinins, whilst inorganic substances are represented by salts. Furthermore, an article dealing with the effects of different forest management practises on soil enzymatic ktivity (including proteases) is adjoined. Its aim is to monitor the effect of forest regenerative elements (forest stand gaps) on enzymatic ktivity, whereas the intervention into forest ktivity changes the moisture and thermal conditions of the site. The results show that out of the organic substances tested L- and D-tartaric acid, proteinogenic and non-proteinogenic amino acids and auxins have a positive effect on the proteolytic ktivity. Conversely, phenols and cytokinins acted as inhibitors. Soil salinization also had a negative effect on proteolytic ktivity of forest soils. The Influence of forest management through forest regenerative elements on soil protease ktivity was not detected. Potential urease ktivity was the only enzyme that reacted to the change of climatic conditions of forest habitat; however, ktiv not a principal topic of this work.
18

Porovnání analytických a senzorických vlastností vín před a po sekundární fermentaci

Prokeš, Kamil January 2016 (has links)
This thesis is focused on sensory and analytical evaluation of wines before secondary fermentation (base wine) and after secondary fermentation using immobilized and classic yeast. The theoretical part is described in detail in the process of autolysis of yeast followed by general issues of amino acids, phenolic and volatile conpounds. Attention is also paid to the issue of the influence of amino acids, phenolic and volatile compounds on the composition and analysis of individual components with the influence of sensory perception for sparkling wines. Sensory perception will be evaluated by the hundred-point scale, and using a profile of strength and flavor profile. These evaluations will be compared on the basis of weighted average evaluation by categorization criteria - before and after the secondary fermentation, depending on the type of wine (base wine, wines produced by immobilized yeast and wines produced by classic yeast), according to the sugar content of musts (17, 19 and 21 ° NM) according to the year (2010 and 2011) and according to the variety (Riesling, Pinot Blanc, Pinot Noir, Sauvignon and Gewurztraminer). For this work, the aim was to determine the amino acids and volatile phenolic substances at the base wine, sparkling wine produced by immobilized yeast and sparkling wine produced by classic yeast. All these analytical values will be compared and evaluated according to the above categorization criteria. Subsequently, the data was statistically processed and evaluated in terms of the various influencing factors and their interactions using the graphical representation and interdependence also used Spearmenových correlations. The work found a statistically significant effect of amino acids threonine, serine, aspartic acid, glutamic acid, glycine, alanine, valine, tyrosine, phenylalanine, beta-alanine, beta-aminobutyric acid, arginine and aminoadipic acid to aromatic profile autolyzátové, which is characterized as flavoring butter, brioche and yeast. For phenolics there was no evidence of a difference in their content before and after secondary fermentation. The biggest factors that impact the content of phenolic compounds is the vintage, the grape variety and the sugar content of the must. It was also found to be a negative effect of phenolic compounds (DPPH Trolox, hydroxycinnamic acids, flavan-3-ols with stilbenes) to sparkle sparkling wines. For volatile substances, the hypothesis was confirmed that certain volatile substances are present only in the base wine, or that their concentration after secondary fermentation decreases and the others in turn are represented only by the wine after secondary fermentation or that their representation increases after secondary fermentation. The content of individual volatile compounds depends on the secondary fermentation, variety, vintage and sugar content of the must. The main objective is to compare among themselves and statistically evaluate the effect of amino acids, volatile and phenolic compounds on the evaluation of the hundred-point scale, the profile of strength and aroma profile. According to this inter-comparison of analytical and sensory evaluation we analyzed the effect of amino acids and volatile phenolic substances on sensory manifestation and the resulting quality of sparkling wines. In the sensory evaluation we found a positive statistically significant correlation between effervescence and autolysis aroma in sparkling wine.
19

Nové materiály na podporu výuky Biochemie na SŠ, Proteiny / Proteins - New educational materials for education in biochemistry at secondary level

Fendrychová, Anna January 2010 (has links)
Diploma thesis is focused on creation of educational materials supporting the education of biochemistry, specifically amino acids and proteins, at secondary level. At first the analysis of Czech chemistry textbooks concerning the two topics - amino acids and proteins was performed. The major problems found were related to the insufficient graphical representation of biomolecules, unsatisfactory motivational components and insufficient integration of the topic with biology or everyday life experience. The supporting educational materials, presented in this work, supplement the widely used chemistry textbooks. The materials includes a graphic oriented presentation, interactive animations demonstrating the process of denaturation and precipitating of proteins at macroscopic and molecular level, poster presenting the structural formulas of standard amino acids, 3D models of selected proteins, additional texts supporting the current topics concerning amino acids and proteins and the laboratory protocols for students. The presented support materials were evaluated at the secondary school conditions. They were tested in one class and the improvement of student's understanding of the topic was compared to the second class employing only the classical educational methods. The comparison of the results of...
20

Význam produkce a kvality pylu letní a podzimní pylové snůšky pro včelstvo (případová studie z okolí obce Volary - CHKO Šumava) / The importance of production and quality of pollen in the summer and late summer for the bee colonies (case studies from around of the village Volary - CHKO Šumava)

PETROVÁ, Jana January 2015 (has links)
Objective of the work was to identify with using pollen analysis botanical origin of bee-colected pollens collected from beehive station Lískovec near the town Volary in the Protected Landscape Area of Šumava. Bee-collected pollens were collected once a week from one honey bee colony with using of a pollen trap. The time of collection was summer and late summer period from 22 June to 11 September 2010. Bee-collected pollens were dried, categorized by color, weighed and observed using the microscope. Pollen grains were determined by the number and type of apertures, shape, sculpture and size. Size of pollen grains was measured on at least 50 pollen grains of one type. In each microscopic slide were counted at least 500 pollen grains. The proportion of plant species in the sample was expressed as a percentage and the importace of plant species was evaluated in the diet of honey bees in the area of interest. Selected samples of bee-collected pollens from beehive station Lískovec and also from beehive station Dobčice were investigated for protein content and amino acid composition. Pollen belonging to Polemonium coeruleum, Trifolium pratense and Trifolium repens was evaluated as an important source of protein and amino acids for honey bees. The concentration of essential amino acids expressed as percentages of total amount of amino acids did not differ significantly between samples of bee-collected pollen. Another objective of the work was to compare the results from the area of interest with the results processed in the similar study from beehive station Dobčice in the northern area of the landscape Blanský les. The work also includes statistical evaluation of dominance, frequency, Shannon-Wiener index of diversity and variability between samples and species. The work is complemented by photographs of selected pollen grains.

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