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Effects of elevated atmospheric carbon dioxide and nitrogen supply on grain quality of wheat
Chadimová, Klára ; Babák, Libor (referee) ; Hrstka, Miroslav (advisor)
The aim of this study was to examine the effect of elevated atmospheric carbon dioxide concentration and different nitrogen fertilization levels on wheat grain quality. Winter wheat cultivar Bohemia was grown under ambient carbon dioxide concentration (AC) and elevated carbon dioxide concentration (EC; 700 mol carbon dioxide per mol) half of the samples was fertilized with 200 kg N per ha (N+) and the other part stayed unfertilized (N-). Zeleny value and Hagberg-Perten value was determined. Bulk density was determined by routine method. Grain hardness, dry matter content, starch concentration and crude protein concentration was determined by NIR spektroscopy. No effect on grain quality was detected due to carbon dioxide enrichment. However nitrogen fertilizer influenced grain quality significantly. Zeleny value and crude protein concentration were decreased and starch concentration was increased in samples that stayed unfertilized. Other grain quality parameters stayed unaffected.
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Impact of elevated carbon dioxide concentration and nitrogen fertilization on protein content of glutenin fraction in winter wheat
Veselá, Markéta ; Vespalcová, Milena (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis studies the impact of elevated carbon dioxide concentration in the atmosphere and nitrogen nutrition on protein kontent in winter wheat (Triticum aestivum) var. Bohemia. Glutenin proteins were separated by SDS-PAGE method and protein quantification was performed by computer densitometry. It was proved that the nitrogen fertilization has a great influence on the amount of glutenin proteins, which increased in all samples. Effect of elevated CO2 concentrationis not nearly as significant, however certain differences can be seen. Samples of wheat grown under conditions of reduced UV radiation, and samples of wheat grown under natural conditions did not show great differences in the content of glutenins.
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Impact of elevated carbon dioxide concentration and nitrogen nutrition on protein content of glutenin and gliadin fraction in winter wheat
Chadimová, Klára ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
The present study investigates effects of elevated atmospheric carbon dioxide concentration, different nitrogen fertilization levels, drought and UV radiation on protein content of wheat gluten fractions glutenins and gliadins. Winter wheat cultivar Bohemia was grown under ambient CO2 concentration (AC; 400 mol CO2.mol-1) and elevated CO2 concentration (EC; 700 mol CO2.mol-1). Half of the samples was fertilized with 200 kg N.ha-1 (N+) and the other part stayed unfertilized (N–). Other environmental factors were UV radiation exclusion (UV–, UV+) and drought (DRY, WET). Gliadins were separated by A-PAGE, glutenins by SDS-PAGE. Proteins were quantified by computer densitometry. Nitrogen fertilization caused an significat increase of gliadins and glutenins. While some gliadins subfractions were significantly lowered by drought, HMW glutenin subunits showed significant increase. UV radiation exclusion resulted in significant decrease of some gliadin subfractions and glutenin subunits. CO2 enrichment caused significant increase of glutenin subfractions HMW 1 and 2, while gliadin subfractions -5 1 and 1 were significantly decreased by elevated CO2 concentration.
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Impact of nitrogen fertilization and drought on gliadins content in winter wheat
Odstrčilová, Eva ; Obruča, Stanislav (referee) ; Hrstka, Miroslav (advisor)
In this diploma thesis the impacts of both nitrogen fertilization and drought on the content of proteins of the gliadin fraction in case of a winter wheat variety Tiguan were observed. Selected samples were cultivated at two locations in a total duration of two years. Two different conditions were selected: one without the nitrogen fertilization (0 kg N/ ha) and the other with the nitrogen fertilization in 140 kg N/ ha concentration. Second observed factor was the drought which was ensured by roofs above the crops and their cultivation in common climatic environment. Gliadin fraction was separated by the A-PAGE method and the protein quantification carried out by a computer densitometry. Such nitrogen fertilization caused a significant increase of gliadins, especially -1,2 and -5 fractions. Stress induced by the drought caused an increase of gliadin content compared to the control sample, particularly in case of - and - fractions. The most important factor influencing the gliadin content in grains was therefore the nitrogen fertilization in a dry environment. The observed increase of gliadin content was lower in case of the sample which was fertilized in a humid environment than in case of the sample which was fertilized in the dry one.
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Influence of carbon dioxide elevated concentration on wheat flour quality
Drahovzalová, Kateřina ; Márová, Ivana (referee) ; Hrstka, Miroslav (advisor)
This thesis studied the influence of elevated carbon dioxide concentration on the properties of ears, grain and flour in two varieties of wheat (Triticum aestivum). The Vánek and Septima varieties were grown in special greenhouses, both in normal atmosphere with carbon dioxide concentration (AC = 385 ?mol?mol-1), and at elevated carbon dioxide concentration (EC = 700 ?mol?mol-1). Quantitative analysis of grain (the content of crude protein, starch, moisture and hardness of grain) was carried out using NIR, gluten content (gluten index) was determined after washing with water and gluten quality was expressed as falling number. Total crude protein content was determined according to Kjeldahl, total amino acids and amino acids content by ion exchange chromatography. Variety Vánek showed significantly larger size of the spikes, more grains and higher grain weight, when it was cultivated in the atmosphere of elevated CO2 concentration. For variety Septima, the size of AC and EC ear variants was comparable, but the ears of corn grown in the EC had a significantly greater number of grains and greater weight. Vánek variety grown in elevated CO2 concentration had lower weight of 100 grains, Septima variety grown in elevated CO2 concentration had greater weight of 100 grains. The varieties Vánek and Septima grown at elevated CO2 concentration showed significantly lower content of crude protein (28.4%) and gluten index (by 34.6%). In comparison with the AC variant, EC also showed lower overall content of crude protein and amino acids.
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Analysis of active substances and biological effects of some non-tradizional cereals
Pecháček, Michal ; Vysoká, Marie (referee) ; Márová, Ivana (advisor)
This thesis deals with the characterization of active substances and biological effects of non-traditional cereals. Basic substances of these non-traditional cereals such as carbohydrates or proteins are characterized in this work. Active compounds such as antioxidants, polyphenols or -glucans are also characterized. These substances were mainly analysed by spectrophotometric methods. The theoretical part describes cereals in general. It focuses on grain morphology, cereal products and mostly on chemical composition. The summary of substances appearing in the cereal grain such as carbohydrates, proteins, vitamins, minerals etc. was processed in this part. In the practical part, the samples of the non-traditional cereals such as amaranth, sorghum, millet, kamut, buckwheat, quinoa, Job’s tears and teff were analysed. Amaranth, millet and buckwheat were also analysed in the form of flakes. Teff was analysed only in the form of flakes. Sorghum and quinoa were analysed also in their coloured variations. Firstly, the water extracts were prepared, then they were used for determination of antioxidant activity, the content of polyphenols compounds and flavonoids. The hydrolysed samples were used for determination of the carbohydrates. For other basic analysis, samples were used in the form of powder. Best results were measured for quinoa, amaranth and buckwheat. Besides basic analysis, the content of -glucans was measured. However, the content of -glucans in these non-traditional cereals was very low. Selected cereals were tested for cytotoxicity on human cells. Cytotoxicity was evaluated by using the MTT cytotoxicity test on human keratinocytes HaCaT and human caucasian colon adenocarcinoma CaCO-2. The sensory analysis was carried out in the last part of the thesis. There were tested 6 samples. From these samples were made muffins that were analysed and sensorically evaluated.
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Monitoring of the wheat quality for food production
Slavíčková, Radka ; Hýsková, Eva (referee) ; Omelková, Jiřina (advisor)
The aim of this study was to monitor the quality of wheat Triticum aestivum, imported into the laboratory MORAGRO after harvest by eight different suppliers, and to evaluate the main quality parameters decisive for the final use of cereal crops. The introduction of the theoretical part was devoted to understanding commercial and agricultural importance of wheat and description of morphological and physiological characteristics of wheat grain. The core of the theoretical part has been focused on the description and explanation of physical and chemical properties of the wheat grain, which largely affect the final product quality of wheat. External factors affecting final quality and yields of wheat were also commented. The experimental part was based on measurements of main quality parameters of wheat (moisture content, bulk density, falling number, amount of gluten and the wheat proteins, sedimentation value and content of additives and impurities). In most cases, measurements were carried out using automated instruments. The quality of wheat was determined based on the obtained results, which allows deciding, whether it is appropriating for food production.
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Impact of elevated carbon dioxide concentration on protein content of gliadin fraction in winter wheat
Šimíčková, Adéla ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
The aim of this bachelor thesis was to study the impact of elevated CO2 concentration, nitrogen fertilization and UV radiation on the content of gliadin fractions in winter wheat. Winter wheat (Triticum aestivum) var. Bohemia was cultivated in conditions with ambient and elevated (700 mol mol-1) CO2 concentrations. Nitrogen nutrition (200 kg N ha-1) was added to half of the samples, while the another half of samples remained unfertilized. Plants were grown in greenhouses both with shielded UV-B radiation and with normal UV radiation. Environment with natural rainfall was the same for all of these variants. Gliadins were extracted by 2-chlorethanol, separated by A-PAGE method and subsequently quantified by computer densitometry. Significant increase of gliadin proteins was noticed in conditions of nitrogen fertilization in natural UV radiation, both in elevated and ambient CO2 concentrations, whereas in an eliminated UV-B radiation significant effect of nitrogen was not observed. Therefore UV radiation influenced in combination with nitrogenous nutrition as stimulative factor. However, statistically significant impact of evelated CO2 concentration on gliadin content was not proved.
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Influence of elevated carbon dioxide concentration on the quality of wheat flour
Zítková, Jana ; Vránová, Dana (referee) ; Hrstka, Miroslav (advisor)
This work treats of influence of carbon dioxide increased concentration on wheat yield and quality of wheat grains and flour. It focuses above all on total content nitrogenous substances in flour, content of proteins, gluten and bake charackteristics. Generally, increased carbon dioxide concentrations cause an increase of wheat yield and decrease of total content of nitrogenous substances. Gluten content is lower and that is why the bake properties are worse too.
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Impact of temperature and drought on gliadins content in two varieties of wheat
Seidlová, Kateřina ; Brázda, Václav (referee) ; Hrstka, Miroslav (advisor)
This bachelor’s thesis focuses on the effect of high temperature and drought on protein content of gliadin fraction on two varieties of wheat. Chosen varieties were Hyfi and Julie, cultivated at 26, 29, 32, 35 and 38 °C during flowering in watering controlled conditions. The condition for ‘wet’ samples was at least 70 % soil moisture and for ‘dry’ samples less than 30 % soil moisture. After harvesting, the seeds were milled into flour from which the gliadins were extracted with 2-chlorethanol. A-PAGE method was used for gliadin separation, quantification was carried out through computer densitometry. A significant genotype effect was discovered. Whilst temperature ranging from 26-38 °C with simultaneous drought stress had no significant effect on gliadin content of Hyfi variation, gliadin content of Julie variation shown obvious maximum at 32 °C. Therefore, Hyfi variation shown better resistance to heat stress than Julie variation. Both variations had higher gliadin content under drought stress than under good watering conditions.
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