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Production and characterization of protein isolates from different kinds of bran
Vybíral, Lukáš ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis deals with the use of various types of bran as a by-product in the milling of cereals. Mills create a huge amount of this material per year. The most common way of processing bran is mostly incineration and to a lesser extent it is used as feed for livestock. Depending on the type of cereal, bran contains 10-20% of protein, which disappears from the food chain due to combustion. Within the framework of sustainability and valorisation of waste, which has recently been largely discussed, great emphasis is placed on waste minimization whether in the field of its production or further processing. Due to the relatively high protein content, bran appears to be a suitable starting material to produce protein supplements. Proteins can be extracted from bran based on their different solubility at different pH. In the alkaline method, the proteins are first dissolved in an alkaline pH and then precipitated in an acidic medium. Lyophilization is followed by characterization of the extract in terms of yield, protein content, moisture, amino acid profile and digestibility. The highest yield was obtained with the oat bran isolate (13,5 ± 0,6 g of isolate per 100 g of bran). In terms of protein content, the best protein isolate was also obtained from oat bran (95,2 ± 0,4% protein in the isolate). Another determination was the analysis of the amino acid profile, in which a high content of arginine was found in all analyzed protein isolates from bran. Determination of digestibility showed very good digestibility of all produced protein extracts from bran.
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The effect of temperature and drought on the glutenin proteins content in two genotypes of wheat
Vybíral, Lukáš ; Vespalcová, Milena (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis deals with the influence of water and temperature deficiency on protein content of gliadin fraction and on glutenin/gliadin ratio in two wheat varieties. The varieties selected for the experiment are called Pannonia and RGT Reform. Samples were cultivated at three different temperatures, 26 °C, 32 °C and 38 ° C, and irrigation was checked at the time of flowering. For wet-grown samples, the soil had a moisture content greater than 70 %, and drought-grown specimens grew on soil with a moisture content not exceeding 30 %. After harvest, the grains were ground into flour and glutenins and gliadins were extracted from the individual samples. SDS-PAGE was used for separation and protein quantification was performed by computer densitometry. A significant effect of the variety on individual gluten proteins was found. In the Pannonia variety, it has been found that the interaction of higher temperature and drought has no major effect on glutenin content and glutenin/gliadin ratio. The RGT variety was significantly affected by these conditions, resulting in a decrease in glutenin content and a significant change in ratio. In both varieties, the glutenin content was higher when cultivated at higher humidity but only at two higher cultivation temperatures.
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Production and characterization of protein isolates from different kinds of bran
Vybíral, Lukáš ; Diviš, Pavel (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis deals with the use of various types of bran as a by-product in the milling of cereals. Mills create a huge amount of this material per year. The most common way of processing bran is mostly incineration and to a lesser extent it is used as feed for livestock. Depending on the type of cereal, bran contains 10-20% of protein, which disappears from the food chain due to combustion. Within the framework of sustainability and valorisation of waste, which has recently been largely discussed, great emphasis is placed on waste minimization whether in the field of its production or further processing. Due to the relatively high protein content, bran appears to be a suitable starting material to produce protein supplements. Proteins can be extracted from bran based on their different solubility at different pH. In the alkaline method, the proteins are first dissolved in an alkaline pH and then precipitated in an acidic medium. Lyophilization is followed by characterization of the extract in terms of yield, protein content, moisture, amino acid profile and digestibility. The highest yield was obtained with the oat bran isolate (13,5 ± 0,6 g of isolate per 100 g of bran). In terms of protein content, the best protein isolate was also obtained from oat bran (95,2 ± 0,4% protein in the isolate). Another determination was the analysis of the amino acid profile, in which a high content of arginine was found in all analyzed protein isolates from bran. Determination of digestibility showed very good digestibility of all produced protein extracts from bran.
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The effect of temperature and drought on the glutenin proteins content in two genotypes of wheat
Vybíral, Lukáš ; Vespalcová, Milena (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis deals with the influence of water and temperature deficiency on protein content of gliadin fraction and on glutenin/gliadin ratio in two wheat varieties. The varieties selected for the experiment are called Pannonia and RGT Reform. Samples were cultivated at three different temperatures, 26 °C, 32 °C and 38 ° C, and irrigation was checked at the time of flowering. For wet-grown samples, the soil had a moisture content greater than 70 %, and drought-grown specimens grew on soil with a moisture content not exceeding 30 %. After harvest, the grains were ground into flour and glutenins and gliadins were extracted from the individual samples. SDS-PAGE was used for separation and protein quantification was performed by computer densitometry. A significant effect of the variety on individual gluten proteins was found. In the Pannonia variety, it has been found that the interaction of higher temperature and drought has no major effect on glutenin content and glutenin/gliadin ratio. The RGT variety was significantly affected by these conditions, resulting in a decrease in glutenin content and a significant change in ratio. In both varieties, the glutenin content was higher when cultivated at higher humidity but only at two higher cultivation temperatures.
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Analýza podmínek spokojenosti zaměstnanců v podniku
Vybíral, Lukáš ; Hrčková, Eva (advisor) ; Surynek, Alois (referee)
Cílem práce bylo vymezení základních pojmů týkajících se pracovní spokojenosti zaměstnanců a následné provedení analýzy ve vybraném podniku. Analýza byla provedena na základě dat získaných především dotazníkovým šetřením, při němž bylo osloveno 170 zaměstnanců v pěti odděleních. Při analýze se sledovala nejen celková pracovní spokojenost, ale také zvlášť spokojenost v každém z vybraných oddělení a zároveň i rozdíly spokojenosti a důležitosti zkoumaných faktorů mezi muži a ženami ve firmě. Na základě výsledků jsem následně navrhl několik řešení, která by mohly napomoct ke zvýšení pracovní spokojenosti v dané společnosti.
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