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Microbial synthesis of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)]
Dugová, Hana ; Zemanová, Jana (referee) ; Kovalčík, Adriána (advisor)
This diploma thesis studied the ability of Cupriavidus malaysiensis, Delftia acidovorans and Azohydromonas lata to produce poly(3-hydroxybutyrate-co-4-hydroxybutyrate), [P(3HB-co-4HB)], by using -butyrolactone and 1,4-butanediol as carbon substrates. The objective of this work was the production and characterisation of isolated polyhydroxyalkanoates (PHA). The theoretical part deals with the basic description and classification of polyhydroxyalkanoates. Next, the biosyntheses of the most investigated PHAs were described. The practical section of the work discusses and presents the output of the cultivation of five bacterial strains selected for the production of [P(3HB-co-4HB)], namely, Cupriavidus malaysiensis (DSM 19379), Delftia acidovorans (DSM 39), Delftia acidovorans (CCM 2410), Delftia acidovorans (CCM 283) and Azohydromonas lata (CCM 4448). The effect of the modified cultivation conditions for each of the used bacteria on the PHA production yields was discussed. The produced biomass after the cultivation was characterised spectrophotometrically, gravimetrically and by gas chromatography. Polymers were isolated from the biomass by the extraction in chloroform. The isolated polymers were characterised from the viewpoint of chemical composition, molecular weight and thermal properties by using Attenuated total reflection infrared spectroscopy, Size exclusion chromatography, Differential scanning calorimetry and Thermogravimetric analysis.
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Study of biodegradation of poly(hydroxy alkanoates).
Wurstová, Agáta ; Přikryl, Radek (referee) ; Obruča, Stanislav (advisor)
The master‘s thesis is focused on the study of biodegradation of polyhydroxyalkanoates, namely polymer polyhydroxybutyrate. The first part of the thesis is focused on the study of biodegradation of polyhydroxybutyrate in the form of crystalline granules of PHB and PHB films using selected species of microorganisms from bacteria, yeasts and fungi. As a representative of bacteria was chosen microorganism Delftia acidorovans, as yeast was selected Aureobasidium pullulans and Aspergillus fumigatus as fungi. PHB depolymerase activity was measured employing turbidemtiric method with suspension of PHB granules as substrate. The results showed that D. acidorovans can partially degrade PHB. On the contrary A. pullulans cannot effectively degrade PHB. The most significant degradation ability revealed A. fumigatus, which was able to degrade PHB completely. Extracellular enzymes excreted by these microorganisms when cultivated on PHB materials as sole carbon sources were analyzed by SDS-PAGE. The second part of the thesis deals with the biodegradation of PHB in the form of PHB film, PHB hardened foil and PHB Nanoul fabric using standard composting test. Semi-solid cultivation showed positive results. In the interval from 14 days to two months were all forms of the PHB completely biodegraded. With semi-solid cultivation was also studied biodegradation rate of the polyurethane elastomeric films which were modified by partial replacement of polyester polyol by PHB. The test samples were prepared using PHB from Sigma and the PHB samples prepared at the Faculty of chemistry VUT. Samples with different concentrations of the dispersed PHB (1 %, 5 % and 10 %) in the polyurethane were also object of the study. At the end of the cultivation (after 2 months) were measured mechanical properties in tension of the material, then efficiency of biodegradation by gravimetric analysis and modification of the material surface by microscopic analysis.
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Microbial synthesis of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)]
Dugová, Hana ; Zemanová, Jana (referee) ; Kovalčík, Adriána (advisor)
This diploma thesis studied the ability of Cupriavidus malaysiensis, Delftia acidovorans and Azohydromonas lata to produce poly(3-hydroxybutyrate-co-4-hydroxybutyrate), [P(3HB-co-4HB)], by using -butyrolactone and 1,4-butanediol as carbon substrates. The objective of this work was the production and characterisation of isolated polyhydroxyalkanoates (PHA). The theoretical part deals with the basic description and classification of polyhydroxyalkanoates. Next, the biosyntheses of the most investigated PHAs were described. The practical section of the work discusses and presents the output of the cultivation of five bacterial strains selected for the production of [P(3HB-co-4HB)], namely, Cupriavidus malaysiensis (DSM 19379), Delftia acidovorans (DSM 39), Delftia acidovorans (CCM 2410), Delftia acidovorans (CCM 283) and Azohydromonas lata (CCM 4448). The effect of the modified cultivation conditions for each of the used bacteria on the PHA production yields was discussed. The produced biomass after the cultivation was characterised spectrophotometrically, gravimetrically and by gas chromatography. Polymers were isolated from the biomass by the extraction in chloroform. The isolated polymers were characterised from the viewpoint of chemical composition, molecular weight and thermal properties by using Attenuated total reflection infrared spectroscopy, Size exclusion chromatography, Differential scanning calorimetry and Thermogravimetric analysis.
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Study of biodegradation of poly(hydroxy alkanoates).
Wurstová, Agáta ; Přikryl, Radek (referee) ; Obruča, Stanislav (advisor)
The master‘s thesis is focused on the study of biodegradation of polyhydroxyalkanoates, namely polymer polyhydroxybutyrate. The first part of the thesis is focused on the study of biodegradation of polyhydroxybutyrate in the form of crystalline granules of PHB and PHB films using selected species of microorganisms from bacteria, yeasts and fungi. As a representative of bacteria was chosen microorganism Delftia acidorovans, as yeast was selected Aureobasidium pullulans and Aspergillus fumigatus as fungi. PHB depolymerase activity was measured employing turbidemtiric method with suspension of PHB granules as substrate. The results showed that D. acidorovans can partially degrade PHB. On the contrary A. pullulans cannot effectively degrade PHB. The most significant degradation ability revealed A. fumigatus, which was able to degrade PHB completely. Extracellular enzymes excreted by these microorganisms when cultivated on PHB materials as sole carbon sources were analyzed by SDS-PAGE. The second part of the thesis deals with the biodegradation of PHB in the form of PHB film, PHB hardened foil and PHB Nanoul fabric using standard composting test. Semi-solid cultivation showed positive results. In the interval from 14 days to two months were all forms of the PHB completely biodegraded. With semi-solid cultivation was also studied biodegradation rate of the polyurethane elastomeric films which were modified by partial replacement of polyester polyol by PHB. The test samples were prepared using PHB from Sigma and the PHB samples prepared at the Faculty of chemistry VUT. Samples with different concentrations of the dispersed PHB (1 %, 5 % and 10 %) in the polyurethane were also object of the study. At the end of the cultivation (after 2 months) were measured mechanical properties in tension of the material, then efficiency of biodegradation by gravimetric analysis and modification of the material surface by microscopic analysis.
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