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Content of toxic and esential elements in bio foodstuffs and their comparing with ordinary foodstuffs
Kohoutková, Nina ; Diviš, Pavel (referee) ; Vitoulová, Eva (advisor)
The aim of this study is to determine the content of toxic and essentials elements in samples of nuts and seeds produced by ecologic agriculture and to compare results with nuts and seeds from conventional agriculture production. These nuts and seeds can be bought in the Czech market (except bio pine nuts, bio pecan nuts and bio pistachios). The amount of elements was analysed using inductively coupled plasma mass spectrometry after previous digestion of samples using microwaves. This study summarizes the main physiological functions of toxic and essentials elements. Results were also compared with another studies. It does not results from all measured amounts of all essential elements, that bio nuts and seeds have higher amounts of these elements; however, all amounts of toxic elements in bio nuts and seeds are lower than in the no-bio ones. For more precise results it would be necessary to measure more samples.
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Possibilities of using of Vitis vinifera as a source of raw materials for cosmetic production
Hanáková, Pavlína ; Vítová, Eva (referee) ; Zemanová, Jana (advisor)
This bachelor thesis deals with preparation of extraction from various parts of grapevine and their consequent use in the manufacture of cosmetics. The theoretical part is focused on general characteristics of grapevine, its taxonomic classification, occurrence and cultivation. Subsequently, the chemical composition of grapevine parts and their uses in cosmetic, food and pharmaceutical industries is described. The final part is devoted to particular types of extractions and methods of determinativ of total phenolic substances. The experimental part deals with the optimization of the prepared extract in order to obtain the extract with the highest amount of total phenolic substances with respect to production costs. Factors such as selection of the appropriate solvent and extraction time are examined. 50% ethanol at the room temperature was found to be an optimal solvent. Finally, the physical and chemical properties, such as density, pH and refractive index were determined for the purpose of producing a material safety data sheet. The extract was processed into cosmetic products.
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Study of Allelopathic Effects of Common Millet on Other Plants
NWAJEI, Lucky
Proso millet (Panicum miliaceum) is an important source of energy and protein for people and as well animals. At present, there are practically no data available on the allelopathic effect of proso millet. The aim of the work was to evaluate the alle-lopathic effects of common millet on selected crops and to suggest the possibility of using the acquired knowledge. Laboratory experiments included evaluation of the effect of extracts from plant parts of millet and millet seeds on seed germina-tion and growth of selected plant species, as well as evaluation of autotoxicity of millet extracts, evaluation of the effect of different densities of millet seeds on allelopathic activity and stability of millet allelochemicals. The most effective extract inhibiting the growth of selected plants was the extract from young millet plants. However, millet allelochemicals do not seem to be suitable for weed control due to their low stability.
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Microbial contamination of raw food and cereal products
VENGLOVIČOVÁ, Kristýna
Plasma has been increasingly used in recent years due to its lethal effect on microorganisms. Foods treated in this way are not a risk to humans in terms of chemical substance. The literature search is focused on raw foods. Description of pathogenic microorganisms frequently occurring on seeds and methods of disposal feasible in accordance with the rules of the raw diet. The aim of this bachelor thesis was to evaluate the effect of low-temperature plasma on seeds. Seed groups were exposed to plasma for 4, 5, 6, 7 and 8 minutes. Seeds of mung beans, broccoli, watercress, radish and barley were treated with the plasma generated in the vacuum chamber. First of all was evaluated the inhibitory effect of plasma treatment on microorganisms occurring on seeds. Furthermore was monitored the impact on the growth of sprouts and roots. Could not be demonstrated the inhibitory effect of plasma on microorganisms present on seeds. The treated seeds compared to the untreated control group were contaminated with a similar amount of microorganisms. The effect on seed development was different for each species.
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The influence of external factors on the growth of selected species of genus \kur{Digitaria}
PAUROVÁ, Natálie
Fonio is native to West Africa and is one of the world's oldest grains. It is a great source of vitamins, minerals, fiber and sulfur amino acids - methionine and cysteine. The aim of the work was to determine the optimal conditions for germination and seed growth of a selected representative of the genus Digitaria in laboratory and field conditions, and to evaluate the possibility of cultivation in the Czech Republic. Under the laboratory conditions were evaluated the effect of drought, salinity,presence of aluminium, waterlogging, light intensity, and storage temperature on seed germination of fonio. Furthermore, laboratory emergence of plants in different substrates and from different sowing depths was also evaluated and a field experiment was performed with different sowing dates. The most suitable temperature for germination of fonio seeds is 30 ° C in the dark. Fonio seeds were resistant to salinity to a concentration of 200 mM sodium chloride. The presence of aluminum had no significant effect on germination. Fonio exhibits very good resistance to waterlogging. Seed germination of fonio was not affected by drought stress up to a PEG solution concentration of 15%. Germination was not reduced by storing the seeds at 21°C for 3 months. The germination of fonio seeds was not significantly affected by the type of substrate or the sowing depth.
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Inquiry methods in educational area Man and his world: Seeds, fruit and young plants
Nikrýnová, Alena ; Stará, Jana (advisor) ; Straková, Jana (referee)
This diploma work deals with the issues of inquiry methods of teaching at primary schools. The theoretical part provides some reflections on contributions and limits of inquiry methods and defines basic inquiry skills. Activities concerning the theme "seeds, fruit, young plants" for the pupils of the 1.-4.grade are suggested in the practical part. Nine of them were tried out in classes. The results of the action research are summarized in the conclusion. They are related to these research questions: 1. How to adjust inquiry activities in a suitable way for their use in the given classes at primary schools? 2. How do children react to this work style? 3. What demands does this work style make on teachers? 4. What problems concerning partial inquiry skills could emerge? How to continue working at them?
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Decisions in seed reproduction in plants
Mašková, Tereza
Seed reproduction is a key part of the life cycle of the most plant species. It allows for the dispersal of species in space and time and, thus, significantly affects dynamics of plant populations and communities. Seed formation, germination and seedling establishment are subjected to selection pressures from the environment and lead to optimization of maternal investments (maternal care), manifested by the number of seeds and amount and composition of nutrients stored in individual seeds. The thesis aims to answer two questions: (i) whether maternal investments in terms of seed mass and seed nutrient stoichiometry is optimized according to the environmental conditions in which seedling development is expected and (ii) how nutrient availability, considering nutrients both stored in the seed by the mother plant and those available in the substrate, affects seedling growth and development. To answer the first question, we focused on interspecific comparisons of seed nutrient stoichiometry linking it with data on seed mass and species niche along gradients of nu- trient availability. We used a phylogenetically informed comparative approach to explore the ratio between phosphorus, nitrogen and nonstructural carbon in seeds from 510 wild herbaceous species. We analyzed seed nutrient stoichiometry with...
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Intraspecific variability in seeds nutrient stoichiometry
Kesl, Tomáš ; Mašková, Tereza (advisor) ; Konečná, Marie (referee)
Immediately after germination, the plants depend on the nutrients stored in the seed from which they germinated, until the nutrient intake is completely replaced by the mature leaves and roots. Nutrients in seeds are important for early development of vegetative organs. Their content and concentration in seeds can be influenced by various factors such as nutrient availability in soil, latitude, temperature, photoperiod, granivory and competition. This bachelor's thesis summarizes current knowledge about intraspecific and interspecific variability of seed nutrient stoichiometry, specifically nitrogen, phosphorus and carbon, as they most often limit plant growth. For all three elements, common and different trends can be observed, both at the intra-species and inter-species level. The only trend comparable between the intra-species and inter-species level is correlation of carbon seed concentration and latitude, while at the inter-species level there is also the opposite trend of negative correlation of latitude and carbon concentration in seeds. Other observed trends are not comparable between the intra-species and inter-species level. It is not possible to compare these trends, as there is lack of studies on the variability of seed nutrient stoichiometry. Therefore it is necessary to focus on seed...
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