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Production of PHB-HV from grape pomace by employing a pure culture of Cupriavidus necator
Jakešová, Michaela ; Kučera, Dan (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis deal with the production of PHB-HV copolymer employing a pure culture of Cupriavidus necator H16. First, Erlenmeyer flask´s cultivations using pure fructose as a source of carbon were performed. The mode of addition of valeric acid for the synthesis of PHB-HV was studied. Furthermore, the effect of stress factor (ethanol) on PHB-HV synthesis by this microorganism was investigated. The method obtained by optimization in Erlenmeyer flasks was applied to the synthesis of the PHB-HV copolymer in the bioreactor using fructose as a source of carbon, too. Furthermore, after enzymatic hydrolysis, a sugar extract from grape pomace was obtained as a source of carbon for the synthesis of PHB-HV. The fermentation in Erlenmeyer flasks and the bioreactor using an extract of grape pomace was carried out. Using this alternative carbon source 3.51 g/l PHB-HV copolymer was produced in Erlenmeyer flask, 5.06 g/l in bioreactor respectively. In the first case, the proportion of 3-hydroxyvalerate in the copolymer was 23.78 mol. % and in the second one, 9.39 mol. %.
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Preparation and characterization of microcrystalline cellulose from food waste
Horáková, Natálie ; Němcová, Andrea (referee) ; Kovalčík, Adriána (advisor)
The aim of the diploma thesis was to isolate microcrystalline cellulose from grape pomace. The analysis of grape pomace showed the following main components: lignin (32.9%), cellulose (34.2%), hemicellulose (31.5%) and lipids (7.0%). Various methods have been tested for the isolation and purification of microcrystalline cellulose. As the most suitable method was selected acid hydrolysis with 50 % and 64 % sulfuric acid followed by treatment with ethylenediamine. The morphology of the isolated cellulose was studied by transmission electron microscopy. The diameter of the hydrolyzed cellulose fibers was determined in the range of 15–130 nm. The isolated cellulose was used as reinforcing filler for agar. The agar/cellulose films were prepared by solution casting. The agar/cellulose films exhibited higher values of Young´s moduli and tensile strength but lower elongation at break compared to neat agar films. The results proved that grape pomace can be used as source for the isolation of microcrystalline cellulose with reinforcing ability for agar.
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Detoxification of coffee sediments by oxidation processes
Maňáková, Helena ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with the detoxification of used coffee grounds by the oxidation processes. The theoretical section describes the characterization of coffee beans and used coffee grounds. Furthermore, this section describes the valorisation of coffee grounds, especially its application as a fertilizer. The final part of the theoretical section focuses on the characterization of phenolic compounds, which are responsible for toxic properties of used coffee grounds, and analytical methods are described, which include UV–VIS spectrophotometry and high–performance liquid chromatography. The aim of the experimental part is the sample preparation, the application of the effective detoxification process and the analysis of the detoxificated used coffee grounds, focusing on the content of phenolic compounds. At the end of the experimental part, data processing is described. Three types of coffee grounds were used for determination of phenolic compounds: raw, defatted and the third type was defatted and simultaneously hydrolysed. High amounts of phenolic acids were identified in every sample, especially the gallic, ferulic, chlorogenic and caffeic acid. After an oxidizing agent was applied, positive detoxification of every sample of used coffee grounds was confirmed. For the most effective and most economical oxidation, a 1% oxidizing agent was chosen, which after a 10–minute oxidization efficiently reduced the content of the phenolic compound.
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Preparation and characterization of microcrystalline cellulose from food waste
Horáková, Natálie ; Němcová, Andrea (referee) ; Kovalčík, Adriána (advisor)
The aim of the diploma thesis was to isolate microcrystalline cellulose from grape pomace. The analysis of grape pomace showed the following main components: lignin (32.9%), cellulose (34.2%), hemicellulose (31.5%) and lipids (7.0%). Various methods have been tested for the isolation and purification of microcrystalline cellulose. As the most suitable method was selected acid hydrolysis with 50 % and 64 % sulfuric acid followed by treatment with ethylenediamine. The morphology of the isolated cellulose was studied by transmission electron microscopy. The diameter of the hydrolyzed cellulose fibers was determined in the range of 15–130 nm. The isolated cellulose was used as reinforcing filler for agar. The agar/cellulose films were prepared by solution casting. The agar/cellulose films exhibited higher values of Young´s moduli and tensile strength but lower elongation at break compared to neat agar films. The results proved that grape pomace can be used as source for the isolation of microcrystalline cellulose with reinforcing ability for agar.
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Detoxification of coffee sediments by oxidation processes
Maňáková, Helena ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with the detoxification of used coffee grounds by the oxidation processes. The theoretical section describes the characterization of coffee beans and used coffee grounds. Furthermore, this section describes the valorisation of coffee grounds, especially its application as a fertilizer. The final part of the theoretical section focuses on the characterization of phenolic compounds, which are responsible for toxic properties of used coffee grounds, and analytical methods are described, which include UV–VIS spectrophotometry and high–performance liquid chromatography. The aim of the experimental part is the sample preparation, the application of the effective detoxification process and the analysis of the detoxificated used coffee grounds, focusing on the content of phenolic compounds. At the end of the experimental part, data processing is described. Three types of coffee grounds were used for determination of phenolic compounds: raw, defatted and the third type was defatted and simultaneously hydrolysed. High amounts of phenolic acids were identified in every sample, especially the gallic, ferulic, chlorogenic and caffeic acid. After an oxidizing agent was applied, positive detoxification of every sample of used coffee grounds was confirmed. For the most effective and most economical oxidation, a 1% oxidizing agent was chosen, which after a 10–minute oxidization efficiently reduced the content of the phenolic compound.
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Production of PHB-HV from grape pomace by employing a pure culture of Cupriavidus necator
Jakešová, Michaela ; Kučera, Dan (referee) ; Kovalčík, Adriána (advisor)
This bachelor thesis deal with the production of PHB-HV copolymer employing a pure culture of Cupriavidus necator H16. First, Erlenmeyer flask´s cultivations using pure fructose as a source of carbon were performed. The mode of addition of valeric acid for the synthesis of PHB-HV was studied. Furthermore, the effect of stress factor (ethanol) on PHB-HV synthesis by this microorganism was investigated. The method obtained by optimization in Erlenmeyer flasks was applied to the synthesis of the PHB-HV copolymer in the bioreactor using fructose as a source of carbon, too. Furthermore, after enzymatic hydrolysis, a sugar extract from grape pomace was obtained as a source of carbon for the synthesis of PHB-HV. The fermentation in Erlenmeyer flasks and the bioreactor using an extract of grape pomace was carried out. Using this alternative carbon source 3.51 g/l PHB-HV copolymer was produced in Erlenmeyer flask, 5.06 g/l in bioreactor respectively. In the first case, the proportion of 3-hydroxyvalerate in the copolymer was 23.78 mol. % and in the second one, 9.39 mol. %.
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