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Biochemical aspects of study and restoration of aged paintings
Hradilová, Iveta ; Hudeček, Jiří (advisor) ; Smrček, Stanislav (referee)
Every part of a work of art is changing in the course of time. Even simultaneously in its creation, when tempera or oil paint used dry up. Already this process can be considered as a biochemical change in the material. The main goal of a submitted bachelor's thesis is to compile recent knowledge about resins and protein media used in works of art, to describe their composition and, in particular to evaluate the changes they undergo in time after their application on canvas, wooden or metal surfaces and paper to their irrecoverable destruction. In addition, biological degradation of these substances by several species of bacteria, yeasts and fungi is discussed in the last part of this work. Key words: resins, terpenoids, protein media, degradation, oxidation, hydrolysis (In Czech)
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Synthesis and photocatalytic applications of titanium dioxide
Solný, Tomáš ; Drbohlavová, Jana (referee) ; Vlček,, Jozef (referee) ; Ptáček, Petr (advisor)
V práci je zkoumán vliv podmínek na průběh hydrolýzy alkoxidů titanu a vlastností připravovaných nanočástic oxidu titaničitého s důrazem na teplotu a množství vody přítomné v systému. Připravované hydrolyzáty alkoxidů titanu a nanočástice oxidu titaničitého připravené z hydrolyzátů jsou studovány metodami XRD, DTA – TGA, SEM – EDS, BET a PCCS. Nanočástice magnetitu byly syntetizovány pomocí precipitační reakce z roztoku Mohrovy soli a jejich krystalová struktura, velikost a povrchové vlastnosti byly sledovány s vyhodnocením vlivu teploty a při modifikaci povrchu polykarboxyletherovým superplastifikátorem. Pro upevnění TiO2 na povrch magnetitu byla použita kombinovaná metoda aplikace vybraných nanočástic TiO2 s hydrolýzou TiO2 pomocí alkoxidů titanu za účelem přípravy fotokatalyticky aktivního core-shell práškového katalyzátoru s vylepšenými vlastnostmi adsorpce na povrchu. Studovány byly možnosti aplikace TiO2 na povrch Mn-Zn feritu, kdy byl studován vliv depozice tenkých vrstev C a Au na morfologii povrchu. Fotokatalytická aktivita vybraných připravených materiálů byla studována pomocí dekompozice methylenové modři v roztoku a par isopropanolu a ethanolu rozkládaných pomocí Mn-Zn feritu v experimentálním chemickém reaktoru s magnetickým polem stabilizovaným ložem nosiče katalyzátoru.
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Utilization of spent wood chips for biotechnological production of PHA
Ladický, Peter ; Sedláček, Petr (referee) ; Obruča, Stanislav (advisor)
The aim of this work was to study the suitability of wood shavings and sawdust as a substrate for microbial production of PHA by bacteria Burkholderia cepacia and Burkholderia sacchari. In the experimental part of the work the most appropriate approach of hydrolysis of wood shaving and sawdust and the effect of polyphenol and furfural concentration on ability to accumulate PHA was studied. Burkholderia sacchari had greater ability to accumulate PHA compared to Burkholderia cepacia. PHB values 87–89 % were achieved when Bulkholderia sacchari was cultivated on medium that contained detoxified hydrolysate of sawdust. Sawdust is therefore a promising substrate for microbial production of PHA in terms of reducing production costs and high content of PHB in biomass.
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Application of Separation Techniques Connected with Mass Spectrometry for the Analysis of Environmentally Important Compounds
Mácová, Daniela ; Čelechovská, Olga (referee) ; Márová, Ivana (referee) ; Demnerová, Kateřina (referee) ; Čáslavský, Josef (advisor)
The identification of the hydrolysis and photodegradation products of flexible polyurethane foams (PUFs) with addition of biooriginated and biodegradable additive was the first topic of this dissertation work. Separation of polyurethane foam hydrolysis degradation products, designed for ecotoxicological tests, was managed by high-performance liquid chromatography coupled with mass spectrometry (HPLC/MS). The degradations product structure was elucidated by tandem mass spectrometry (MSn). PUF photodegradation products were obtained by exposure of materials by irradiation at 254 nm. Semi-volatile degradation products were isolated from the exposed polyurethane by n-hexane extraction; volatile compounds were collected by solid phase microextraction (SPME). Gas chromatography with mass spectrometry (GC/MS) and complete orthogonal tandem gas chromatography with mass spectrometry (GCxGC/TOF MS) was used for separation and identification of photodegradation products. The influence of the bio-filler on the character of degradation products and the possible effect of PUF degradation products on the environment was discussed at the end of this section. The determination of isoprostanes – markers of oxidative stress in tissues of beadlet anemone (Actinia equina) was the subject of the second topic. F2-isoprostanes were synthesized from the arachidonic acid. With thereby prepared isoprostanes the method of determination by liquid chromatography with tandem mass spectrometry (HPLC/MS/MS) was developed and optimized. The isoprostane isolation process from the Actinia equina tissues was optimized with solid phase extraction (SPE). The resulting methodology was used to quantify isoprostanes in tissues of anemones, which were exposed to both moderate and high temperature changes. The temperature changes were used to initiate the oxidative stress in organisms. In addition, concentration levels of unknown compounds were also monitored. These unknown compounds were extracted from tissues together with F2-isoprostanes and their identity is discussed in this dissertation work too. The possibility of using isoprostane levels in the Anthozoa tissues for the oxidative stress monitoring is discussed in the conclusion of this work.
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Utilization of lignocellulose materials for biotechnological production of polyhydroxyalkanoates
Kučera, Dan ; Márová, Ivana (referee) ; Obruča, Stanislav (advisor)
Tato diplomová práce se zabývala možnostmi utilizace lignocelulosového materiálu jako obnovitelného zdroje k produkci polyhydroxyalkanoátů (PHA) biotechnologickými metodami. Teoretická část práce se zaměřuje na charakterizaci rostlinné odpadní biomasy, její enzymatickou sacharifikaci a možnosti produkce a izolace hydrolytických enzymů. Dále se pak literární rešerše zabývá bakteriální produkcí PHA a možností využití lignocelulosové biomasy pro jejich produkci. V rámci experimentální části byly vybrané odpadní substráty hydrolyzovány chemickou a enzymatickou cestou. Jako odpadní substráty byly použity výlisky z jablek, hroznového vína a řepky olejné a kávová sedlina. Získané hydrolyzáty byly použity k produkci PHA bakteriálním kmenem Burkholderia cepacia. Nejslibnějším substrátem se jevily výlisky z jablek. Ukázalo se, že vybraný bakteriální kmen je schopen utilizovat odpadní substráty i bez předchozí úpravy. Supernatant po skončení kultivace jevil následující aktivity: proteasovou, lipasovou (0.47 nmol/(mL•min)), celulasovou pro CMC (6.05 nmol/(mL•min)) a filtrační papír (4.63 nmol/(mL•min)) a xylanasovou (1.71 nmol/(mL•min)). Tyto enzymy mohou představovat zajímavý vedlejší produkt výroby PHA z odpadních zemědělských materiálů. V rámci této práce byl také posouzen vliv délky kultivace a způsob hydrolýzy na výslednou produkci PHA a enzymatickou aktivitu průmyslově zajímavých enzymů.
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Immobilization of selected glycanohydrolases
Reichstädter, Marek ; Trachtová, Štěpánka (referee) ; Omelková, Jiřina (advisor)
The theoretical part of this thesis deals with cellulolytic enzymes, their microbial producers, the possibilities of using such enzymes in the industry and how can be enzymes - not only cellulolytic - immobilized. Experimental part examines the preparations created by immobilizing various amounts of the commercially used cellulolytic complex Cellulast 1.5L onto various synthetic carriers made of polyethylene terephthalate - commercially used Sorsilen, PET carrier and glutaraldehyde-treated PET carrier. Enzyme activity of these preparations was determined by Somogyi - Nelson method by spectrophotometry. For the highest activity immobilized preparation was determined the temperature- and the pH-optimum. The difference in effects change between the free and immobilized enzyme by measuring viscosity decrease of the substrate depending on the degradation of glycosidic bonds was also studied.
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A bioconversion study of cellulosic waste to ethanol using yeasts systems
Čalová, Iveta ; Vítová, Eva (referee) ; Babák, Libor (advisor)
This diploma thesis deals with the optimization of the production of ethanol from waste paper using yeast. There were used 4 kinds of paper as a substrate - office paper, non-recycled workbook, recycled workbook and newspaper. All papers were pretreated with the following procedures: grinding, microwaves + NaOH, microwave + H2SO4 and microwave + H2SO4 + NaOH. The glucose concentration was determined in enzymatic hydrolysis by HPLC. Saccharomyces cerevisiae were chosen for ethanol production. The production of ethanol was carried out with all the pretreated papers in simultaneous saccharification and fermentation. During hydrolysis, the pretreated papers have reached the highest results in the combination with microwave + H2SO4 + NaOH. Non-recycled workbook was the only exception, where the highest concentration of glucose has been obtained by the pretreatment of microwaves + H2SO4. Following results have been acquired: office paper 24,69 gdm-3, non-recycled workbook 22,47 gdm-3, recycled workbook 16,94 gdm-3 and newspapers 15,36 gdm-3. SSF was carried out again with all the papers and their pretreatments. The highest concentration of ethanol has been achieved in microwave pretreatment + H2SO4 + NaOH. The highest overall concentration has been gained from the office paper, amounted to 16,98 gdm-3. The maximum concentration of ethanol for non-recycled workbook has been 15,25 gdm-3, for recycled workbook 12,2 gdm-3 and for newspapers 12,59 gdm-3.
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Use of Kluyveromyces marxianus to bioethanol produce from waste paper
Tomečková, Andrea ; Hrstka, Miroslav (referee) ; Babák, Libor (advisor)
The diploma thesis is focused on production possibilities of bioethanol from waste paper by yeast Kluyveromyces marxianus. Waste cardboard was used as a potential substrate for bioethanol production. Several methods for cardboard preparation were introduced and compared as well as methods of fermentation. Simultaneous sacharification and fermentation and separate hydrolysis and fermentation of preprepared cardboard paper were performed in different pH buffer (4,8-7). Simultaneous sacharification and fermentation was held at a temperature of 45°C. Hydrolysis in separate hydrolysis and fermentation was performed at 50°C and fermentation at 25°C. Procedures outputs were obtained by sampling in specific time intervals and samples were analyzed by HPLC for presence and concentration glucose and ethanol. The results of the analysis have shown that the highest concentration of glucose produced by enzymatic hydrolysis was achieved by using microwaves, 2% H2SO4 and 2% NaOH pretreated paperboard at pH 4,8. The highest yield of ethanol was obtained by separate hydrolysis and fermentation of pulp pretreated by microwaves, 2% H2SO4 and 2% NaOH in pH 5,4 buffer. The method SHF proved to be more effective for the production of ethanol than SSF.
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Optimization of bioethanol production by Zymomonas mobilis
Andrlová, Kateřina ; Vítová, Eva (referee) ; Babák, Libor (advisor)
Diploma thesis deals with use of Zymomonas mobilis for the production of bioethanol from waste paper. There were used three kinds of substrate (cardboard, drawing and office paper) to optimize of bioethanol production. Individual papers were subjected to the same pre treatment, namely a milling, a combination of microwave irradiation and NaOH, a combination of microwave irradiation and H2SO4 and combination microwave irradiation, H2SO4 and NaOH. The substrates were decomposed by enzymatic hydrolysis after pre treatment to evaluate the best pre-treatment. Simultaneous saccharification and fermentation was carried out for each substrate (with two of the best pre-treatment). The samples were taken during the hydrolysis and the simultaneous saccharification and fermentation, and were determined by HPLC. Growth curves of Zymomonas mobilis were constructed, as the most appropriate for SSF was chosen temperature of 40 ° C in which the exponential phase took place at the time of 6 15 hours. During hydrolysis was monitored glucose concentration in the solution. The maximum concentration of glucose was in the cardboard (microwaves + H2SO4 + NaOH) 16.46 gdm-3, a drawing (microwaves + H2SO4 + NaOH) 31.78 gdm-3, and office paper (microwaves + H2SO4) 25.04 gdm-3. The concentration of ethanol for SSF was highest in the same cases as in the hydrolysis. The cardboard was the maximum concentration of bio ethanol 9.5 gdm-3, for the drawing 16.1 gdm-3 and for the office paper 12.13 gdm-3.
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