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The Effect of Environmental Contamination on Quality of Leafy Vegetables
Jančíková, Silvie ; Pavlíková, Daniela (advisor) ; Veronika, Veronika (referee)
Heavy metals are widely distributed throughout the environment, but environment can be contaminated by these elements originated from anthropogenic activities. These toxic elements can be taken up by plant. Heavy metals accumulation and their uptake by plants depend on plant species, plant growing period, part of plant, soil characteristics (content of organic matters, physical chemical properties), interactions between metals etc. High concentrations of metal ions in plants can result in metabolic stress and so the plant metabolic stress mechanism can be induced : organic acids exudation, heavy metals binding in cell walls, phytochelatins synthesis etc.
In case, that various protective mechanisms against toxic elements are not successful, heavy metals cause the damage to plant metabolism. This is indicated by changes in the contents of amino acids and fatty acids, enzymatic changes, inhibition of yield of aboveground biomass, chlorosis of leaves.
There is an important difference between Zn and the other elements. Zn is an essential micronutrient and its content in contrast to the other elements without biological function is less toxic for plants.
Vegetables are rich sources of essentials nutrients and heavy metals can significantly affect their quality. The consumption of contaminated vegetables may result in negative effects on nutritional composition. Leafy vegetables have relatively higher concentrations and transfer factors of heavy metals in contrast to root and fruit vegetables. There is the high health risk to consume the vegetable which is exposure to heavy metal polluted environment.
The majority of European agricultural soils is safe for food production, but the areas with the high population density (China) have level of contamination which present ecological and health risk. For this reason many studies have focused on crop accumulation of heavy metals in such areas.
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Interactions of Hydrogen Sulfide Releasing Enzymes in Porcine Oocytes during Meiotic Maturation
Jiříček Hasalová, Simona ; Hošková, Kristýna (advisor) ; Tomáš, Tomáš (referee)
The reproductive biotechnologies currently represent a major scientific discipline based on a sufficient quantity of wholesome oocytes matured in vitro conditions to acquire permits for their effectiveness. The meiotic maturation is a complex process where a wide range of factors is involved in the regulation. One of these factors are small gaseous molecules, so-called gasotransmitters. These gases demonstrate number of physiological functions in the organism and the latest discovered gasotransmitter is hydrogen sulfide (H2S).
The aim of this thesis was to test the hypothesis according to which there are enzymes present in porcine oocytes that produce H2S (CBS, CTH, 3-MPST), their distribution is in interaction and their joint actions influence the process of the meiotic maturation. The resulting data were obtained on the basis of immunocytochemical staining and colocalization analysis.
The results proofed the presence of H2S-releasing enzymes in porcine oocytes. It was also confirmed the function of these enzymes in relation to the regulation of the meiotic maturation when oocytes cultured with triple inhibitors of H2S-releasing enzymes matured more slowly. The results also showed medium correlation dependence of enzymes CBS, CTH and 3-MPST. The combination of CBS and 3-MPST resulted in high correlation dependence which confirmed their interaction both in immature oocytes and in vitro matured oocytes.
It is evident that so far studied effects of H2S are only a fraction of skills which this signal molecule possesses. There exists a need for future experiments to help us describe and explain the acting mechanisms of H2S.
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Mutational analysis of Potato virus X (PVX) coat protein
Werschallová, Markéta ; Ryšánek, Pavel (advisor) ; Jan, Jan (referee)
The thesis deals with the mutational analysis of conserved amino acids of Potato virus X coat protein (PVX CP). The importance of selected amino acids for the spread of the virus in the plant should be determined. Nicotiana benthamiana was selected as an experimental plant. Mutations of the PVX CP were based on the comparison of PVX CP amino acid sequence with the sequence of Papaya mosaic virus coat protein (PapMV CP), the only representative of potexvirus, which includes PVX, with the described crystal structure of the CP. The importance of certain amino acids for interaction of coat protein subunits PapMV CP,CP and PapMV CP,RNA and thus for virus particles formation was experimentally determined. The available amino acid sequences of isolates and strains of PVX CP were obtained from the National Center for Biotechnology Information (NCBI) database, compared with each other and alsowith the sequence of PVX CP used in the Laboratory of Virology, Institute of Experimental Botany of the CAS. Codons encoding conserved phenylalanine and lysine at positions 33 and 118 in the PVX CP amino acid sequence were mutated using methods of molecular biology.
Five constructs of PVX CP mutants were prepared, Two deletion mutants of the PVX CP N-terminus which were created in the vector derived from PVX (pGR106) in which the cDNA sequence of PVX is integrated, the remaining 3 point mutants were prepared only as a product of SOE PCR. The reporter gene GFP for monitoring of infection and spread of mutants in plant tissue was cloned into pGR106 carrying the deletion mutants of the N-terminus of PVX CP (deletion of 2.-32. or 2.-33. amino acid). Both mutants are able to move only in a short distance from infected cells to adjacent cells within the inoculated N. benthamiana leaf. These two deletion mutants showed difference in the speed and in the extent of the GFP signal spread. Deletion mutant still possessing the codon for F33 showed faster onset of the GFP signal and was able to spread more rapidly to surrounding cells in comparison with deletion mutant, where the codon for F33 was removed. Other mutants carrying the point mutations were also prepared: the deletion mutant of the codon for F33 (deletion F33), the substitution mutant, in which the codon for phenylalanine at position 33 was replaced by the codon for alanine (F33A) and substitution mutant, where the codon for lysine at position 118 was replaced by the codon for alanine (K118A). Unfortunately, all three point mutants could not be cloned into the vector pGR106, therefore, the evaluation of their spread in N. benthamiana plants was not possible.
Based on obtained results it is possible to conclude that the amino acid F33 is important for the intercellular movement within the neighboring cells. To assess the importance of the amino acids F33 and K118 in the systemic infection, it would be necessary to evaluate also the point mutants deletion F33, F33A, and K118.
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Interspecific interactions in wetland communities in dependence on water regime: long-term test of stress-gradient hypothesis
Růžičková, Kateřina ; Douda, Jan (advisor) ; Alena, Alena (referee)
The Stress-gradient hypothesis predicates a change of interspecies relations from negative to positive according to the stress gradient. The basic assumption is that the presence of one species (the facilitator) makes the growth of other species easier. In this study was determined based on the 5years experiment, whether the interspecies interactions (i.e. the importance of facilitation and competition) changes according to the hydrological conditions. Three wetland species (Calamagrostis canescens, Carex elongata and Deschampsia cespitosa) were planted in experimental pots with the presence and absence of the dominant species (Carex elata). The hydrological gradient (= the stress gradient) was simulated by three types of hydrological conditions: dry, fluctuating and wet. The success of the species within the specific conditions was correlated with the fitness-related characteristics of the plants including the biomass, the number of ramets and the height of the plants. Following hypotheses were tested: i) at a low intensity of stress (with the wet treatment), the C. elata represents a competitor for other species. On the other hand, at a high intensity of stress (with the dry treatment), the C. elata represents a facilitator, making it easier to the other coexisting species to grow. This presumption was confirmed only with the D. cespitosa, which was more successful under dry treatment with the presence of a dominant species, which facilitated it. With the other two species the change of interspecific relations was not observed and the relationships remained negative. Furthermore the results showed, that in the dry treatment with the presence of a dominant species, there was a lower intensity of competition among the coexisting species. The experiment showed, that the interactions of particular species with dominant species can vary according to the stress gradient. The hydrological gradient also influences the character and intensity of interactions among the species.
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The effect of age and gender on performance and carcass parameters of nutrias
Bubeník, Tomáš ; Tůmová, Eva (advisor) ; Zdeněk, Zdeněk (referee)
In the thesis we aimed on data connected with slaughter analysis of the body, carcass yield,
feed conversion and content of chemicals, including pH of thighs and loin. In the experiment,
we used standard nutrias which have been weaned at the second month of age. There were 90
nutrias in the experiment. Nutrias were fed with complete feed mix - made by Kooperace
Hrotovice created by CLUS in Prague utility model UV 24096, ad libitum. Nutrias were
weighted every 28 days. At the age of 6, 7, and 8 months, 6 females and 6 males were chosen
and slaughtered. Results were analysed by variation of analysis, ANOVA method and with age
and sex interactions. We have used value P <= 0,05 as statistical significant difference. As a result, we have found out that males grew significantly (P <= 0,05) faster than females. The
highest feed conversion was recorded at 4th month of the experiment. Influence of age on the
weight of carcass without a head and organs was observed (P <= 0,029), carcass weight of
males increased significantly (P <= 0,001). Fat percentage was influenced by both sex
(P <= 0,001) and age (P <= 0,001). It loin part weight decreased with growing age (P <= 0,001),
and was significant (P <= 0,029).according to sex with lower decreasing in males. For the loin
percentage, there was recorded interaction of sex and age (P <= 0,038) and was affected by age
(P <= 0,007) and sex (P <= 0,007) as well. Decrease was significantly faster in females. The pH
values of loin and thighs were growing with age (P <= 0,001) and were influenced by sex as
well, for loin (P <= 0,013) and thighs (P <= 0,016). For proteins we have recorded significant
interaction of sex and age (P <= 0,009). Fat content was higher in females (P <= 0,009).
Conclusion of the thesis showed, that nutrias can be slaughtered in the age of six months,
without a negative on effect meat quality. Males are better in carcass yield, higher protein
content and lower fat percentage, in comparison of same age of females.
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Effect of Camellia sp. on dairy matrix digestion
Scholzová, Tereza ; Potůčková, Miroslava (advisor) ; Vladimír, Vladimír (referee)
The aim of this bachelor thesis is to summarise of current knowledge about the effects and biological properties of the substances contained in leaves of Camellia sinensis, their digestion and their effect on the digestion of dairy matrices. Camellia sinensis is a plant, which is used to tea production. Tea is manufactured by fermentation of tea leaves and according to its degree it is possible to prepare different kinds of this product. The best known are green, black and oolong tea. Beverages prepared from tea leaves contain many bioactive compounds, including alkaloids, free amino acids, proteins and vitamins. However, the most important are polyphenolic substances flavonoids, which are also the major bioactive constituents of tea. These compounds have many pharmacological properties such as antiatherosclerotic, antibacterial, anticancer, antiviral, hypolipidemic and hypocholesterolemic.
The effect of milk on the biological activity of tea polyphenols has been a subject of many studies but the mechanism by which the antioxidant activity of this compounds affect milk and dairy products and especially their digestion process has not been fully understood yet. It was found that flavonoids can interact with proteins rich in prolin, including also casein, via covalent and noncovalent interactions, especially by hydrophobic interactions and hydrogen bonds. The resulting complexes may destabilize protein molecules and cause their precipitation, thereby their digestibility is improved. On the contrary, stable complexes protect polyphenols from autooxidation. Interesting is also crosslinking effect of green tea flavonoids on milk proteins. These substances also have the ability to form complexes with lipids and lipolytic enzymes and so decrease lipids digestion and absorption, including the milk fat and its accompanying components such as cholesterol. It was also observed reduced absorption of other fat-soluble substances like persistent organic compounds.
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Phenomenon Body modification: The sociological interpretation.
Kolářová, Sára ; Paulíček, Miroslav (advisor) ; Kotík, Michal (referee)
The thesis is focused on the research of subjects who are specifically standing out due to their different visual appearance thanks to extreme Body modifications that they have done on their bodies. It explores whether they are just independent individuals with no subcultural relations or whether they belong to a certain closed social group that stands on common values which are manifested through modifications. The theoretical part deals with frameworks that could more precisely define their interaction. The author seeksout for subcultural signs because recent Body modification literature suggest that these individuals might be members of a group called Modern primitives, which meets all the characteristics necessary for the existence of a subculture. However on the basis of primarily semi-structured interviews author dicovers that these people do not fit their beliefs into such a framework and their interactions and shared values are not extensive. The results of the work thus points to the fact that individuals with Body modification can be consistently assigned to one of shared social identities that helps them find themselves. If there is a binding element between them at a higher level, it's the so-called suspension, in other words: being hanged on hooks, where their interaction is necessary.
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Dog and Woody Plant
Macková, Eva ; Kunt, Miroslav (advisor) ; Buttry, Ivana (referee)
The thesis deals with the topic Dog and tree species as part of the history and present life in our society. The aim of this thesis is to determine how strong and equal place a dog and wood in the Czech Republic have and which interactions between them can occur. According to the fact that the care, attitude and responsibility are given by laws governed by the Czech Republic and individual towns and villages,the thesis is mapping the current situation
in selected districts of the city of Prague 6 and Prague Suchdol, as part of the capital Prague. The thesis is divided into 3 parts. The first part is focused on describing the relationship of a dog and tree species in our
country and nation which demonstrates their stable position without the need to compare. The second part is based on literature and available resources. It works with partial
factors that may be relevant in possible interaction. It draws on the knowledge of modern cynology, especially the knowledge of the current activities of the dog and its ethology and on current knowledge in the field of dendrology, with emphasis on the selection of trees that
are suitable for human settlements while they are in our territory as a native species. Within ethology the thesis describes the behavior of dogs along with the potential interaction with wood arising therefrom, including poisonous trees which the dog may come in contact with.
The third part deals with specific situations associated with the free movement of dogs in Prague as a whole and focuses on some of its parts. Currently, this issue is very topical in Prague and no decision of the final form of the governing ordinance has not been made yet
by the Prague City Council.
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Mass Size Distribution of Water Soluble Ions in Prague and Wiena in Summer
Schwarz, Jaroslav ; Vodička, Petr ; Zíková, Naděžda ; Hitzenberger, R.
Aerosol mass size distribution is a key factor that influences aerosol behavior both on local (health effects, visibility) and global (global warming) level. The content of water soluble ions is the most important factor controlling hygroscopic behavior of aerosol particles. Hygroscopicity is a substantial parameter for particle deposition in lungs, particle – cloud interactions, aerosol optical effects etc. Therefore we studied size distribution of water soluble ions in two Central European capitals – Prague and Vienna. In this work, the results from summer campaigns are presented.
Fulltext: content.csg -  PDF
Plný tet: SKMBT_C22012102615330 - PDF
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