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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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Biotechnological production of selected metabolites on whey substrate
Gadová, Martina ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
The submitted master thesis deals with assessment of the possibility of using of cheese whey for biotechnological production. Study content composition of lyophilized whey, optimization of acid hydrolysis and preparation of cultivating mediums with different content and treatment of cheese whey. Between the aims of this thesis belong also screening of microbial producers, interesting for biotechnology and looks at their growth and production of selected metabolites of cultivation mediums containing cheese whey. All substrates and produced metabolites where examined with UHPLC-PDA-RI and GC-FID: Amount of produced microbial lipids was determined by gravimetric analysis. Examined microorganisms belonged to yeast genus Saccharomyces, Metschnikowia and bacterial genus Lactobacillus and its focused on production of ethanol, microbial lipids and lactic acid. The highest yields with using yeasts were obtained using production medium containing hydrolysed lactose in cheese whey. The highest production, in case of bacteria, was obtained using non-hydrolysed, untreated cheese whey production medium.
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Biotechnological production of polyhydroxyalkanoates using wastes of coffee production
Vašíčková, Monika ; Benešová, Pavla (referee) ; Obruča, Stanislav (advisor)
This bachelor thesis is focused on study of production of polyhydroxyalkanoates (PHA) by bacteria Burkholderia cepacia and Burkholderia sacchari. Production of PHA has been studied using spent coffee grounds hydrolysates which have been prepared by different aproaches. In the thesis is compared standard method of coffee ground hydrolysis by mineral acid followed by enzymatic hydrolysis. Hydrolysates which have been produced were analyzed in terms of concentration of saccharides and efficiency of hydrolysis. The best producer of PHA (based on results) was bacterium Burkholderia cepacia, in the medium which has been prepared by hydrolysis of spent coffee grounds extracted by 60% solution of ethanol. Biomass yield of this cultivation was 3,553 g/l with 32,472% PHA content. This PHA contained 6,09% 3-hydroxyvalerate. In the other experiment, we verified alternative hydrolysis of spent coffee grounds – by commercially available enzymes. We used cellulase, hemicellulase and the enzymatic cocktail which has been produced by mould. Hemicellulase was the most effective hydrolytic enzyme and its application resulted in production of the highest amount of biomass – 5,708 g/l. In this cultivation, only homopolymer PHB has been which is probably caused by the fact, that during the enzymatic hydrolysis levulinic acid or any other potential precursor of 3HV is formed.
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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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Biotechnological production of selected metabolites on whey substrate
Gadová, Martina ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
The submitted master thesis deals with assessment of the possibility of using of cheese whey for biotechnological production. Study content composition of lyophilized whey, optimization of acid hydrolysis and preparation of cultivating mediums with different content and treatment of cheese whey. Between the aims of this thesis belong also screening of microbial producers, interesting for biotechnology and looks at their growth and production of selected metabolites of cultivation mediums containing cheese whey. All substrates and produced metabolites where examined with UHPLC-PDA-RI and GC-FID: Amount of produced microbial lipids was determined by gravimetric analysis. Examined microorganisms belonged to yeast genus Saccharomyces, Metschnikowia and bacterial genus Lactobacillus and its focused on production of ethanol, microbial lipids and lactic acid. The highest yields with using yeasts were obtained using production medium containing hydrolysed lactose in cheese whey. The highest production, in case of bacteria, was obtained using non-hydrolysed, untreated cheese whey production medium.
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Biotechnological production of polyhydroxyalkanoates using wastes of coffee production
Vašíčková, Monika ; Benešová, Pavla (referee) ; Obruča, Stanislav (advisor)
This bachelor thesis is focused on study of production of polyhydroxyalkanoates (PHA) by bacteria Burkholderia cepacia and Burkholderia sacchari. Production of PHA has been studied using spent coffee grounds hydrolysates which have been prepared by different aproaches. In the thesis is compared standard method of coffee ground hydrolysis by mineral acid followed by enzymatic hydrolysis. Hydrolysates which have been produced were analyzed in terms of concentration of saccharides and efficiency of hydrolysis. The best producer of PHA (based on results) was bacterium Burkholderia cepacia, in the medium which has been prepared by hydrolysis of spent coffee grounds extracted by 60% solution of ethanol. Biomass yield of this cultivation was 3,553 g/l with 32,472% PHA content. This PHA contained 6,09% 3-hydroxyvalerate. In the other experiment, we verified alternative hydrolysis of spent coffee grounds – by commercially available enzymes. We used cellulase, hemicellulase and the enzymatic cocktail which has been produced by mould. Hemicellulase was the most effective hydrolytic enzyme and its application resulted in production of the highest amount of biomass – 5,708 g/l. In this cultivation, only homopolymer PHB has been which is probably caused by the fact, that during the enzymatic hydrolysis levulinic acid or any other potential precursor of 3HV is formed.
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The application of the process of high-pressure hydrolysis with nitric acid at the production of biogas from hay
VANĚK, Zbyněk
This thesis deals with the technology of the high pressure hydrolysis with nitric acid (HNO3) in biogass production from the hay. The theoretical part is focused on the basic information about the acid hydrolisis. Much attention is ingaged in the lignocellulosic materials and methods of their treatment.The hay was crushed, pelleted and subsequently subjected the acid hydrolysis in the high-pressure hydrolyzer (UV CZ 21314) at pressures (0,475 MPa, 0,934 MPa, 1,611 MPa). As the hydrolysis reagent was used highly concentrated (65%) nitric acid (HNO3). The pressure was achieved in the hydrolyzer by the steam in temparature of 190°C, the residence time of the phytomass in the machine was 500s. Based on the mapping process with wide CO2 production were selected the interesting areas, which were subsequently carried out detailed mapping process using batch simulations at CH4 production. After the mathematical interpolation of the maxima the values were used in the economic analysis, that fully respects the technological possibilities and legislative constraints.
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Using high-pressure hydrolysis process with sulfuric acid to produce biogas from wheat straw
HŮRKOVÁ, Drahomíra
The presented dissertation assesses the technological and economical use of high-pressure hydrolysis of wheat straw with sulfuric acid (H2SO4) for biogas producing. The theoretical part is focusing to the structure of lignocellulosis phytomass, on technology of mechanical treatment and acid hydrolysis. The experimental part is based on the production of neutralized hydrolyzate obtained by using technology of high-pressure hydrolyse by pressure 1,5 MPa, in retention time of 500 seconds and 190 °C. Data, generated by operation server Linode Platform Manager, emerges, that the area with the best polynormal cubic function, which is aproximated by the smallest mistake. The local extremes, where are the verification of the cumulative CH4 by anaerobic fermentation (in thermophilic area by temperature 51 °C) in relation on dry matter, are calculated of tha data obtained of Maple 14. The highest yeld of CH4 production was found by pressure of high-pressure hydrolyser 2,37 MPa. The maximum value of production of biogas (CH4) was 190 m3. t-1 of dry phytomass. Based on the optimalization, was maximum yeld of CH4 (of biochemical aspects) found about dry matter 8,57 % and pH 4,84. From the managerial point of view, which takes into account technological limitations and financial indicator, are the optimal conditions by dry matter from 3,92 to 5,12 % and a pH of 3,2 to 5,1.
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