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Degradace syntetických barviv pomocí Phanerochaete chrysosporium
Blahutová, Andrea
Azo dyes are the most important and largest group of commercially produced synthetic dyes. Their degradation by white-rot fungi Phanerochaete chrysosporium is induced by a lignin-degrading enzyme system, which is capable of degrading xenobiotic compounds. This bachelor thesis focuses on the degradation of the five most commonly used azo dyes by Phanerochaete chrysosporium. The process has been monitored not only on individual dyes (E102 Tartrazine, E110 Yellow, E122 Azorubin, E124 Ponceau 4R and E123 Amaranth), but also on two alimentary products (Vitacit – lemon and Vitacit – strawberry) containing E102 Tartrazine or E122 Azorubin azo dye. The absorbance of the solutions was measured spectrophotometrically at four-day intervals across a twenty-day cultivation period. The color loss was calculated based on the recorded values and the results were expressed as a percentage of decolorization. At the end of the measurement, the Azorubin dye showed the highest decolorization (90 %), whether the Ponceau 4R dye was decolorized the least (20 %). The level of decolorization of the powdered beverage solutions was compared with the decolorization of the individual dyes. The degradation was mainly effected by the various azo dyes structure. The composition of powdered beverages also played a role in their degradation.
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Processing optimalization of biodegradable starch based packaging and its characterization for adaptation on production technology
Krahulová, Veronika ; Ondreáš, František (referee) ; Lepcio, Petr (advisor)
This diploma thesis focuses on the problematics of preparation of biodegradable starch based packaging. The aim of the thesis is to optimize the preparation and verify the characteristics for further adaptation and production technologies. The films consisted of starch, PVA and glycerol. Four types of starches, three types of PVA and different ratios of glycerol were tested. Films were prepared by casting with glycerol as a plasticizer, instead of distilled water, to reduce the energy cost of the preparation. The mechanical properties of the films were tested as well. The experimentally determined values of elongation at break and tensile strength of the wheat starch films were compared with a semiempirical model. Results revealed that the preparation of thermoplasticization of starch with glycerol leads to a considerable increase in elongation at break but at the same time to a marked decrease in tensile strength compared to the preparation from solution. The rheological properties of the prepared films were also investigated. Infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) were used to study the structure of the films.
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Biodegradation of bioplasts in compost environment
Vodička, Juraj ; Kovalčík, Adriána (referee) ; Obruča, Stanislav (advisor)
This master’s thesis focuses on biodegradation of polyhydroxybutyrate (PHB) and polylactic acid (PLA). The theoretical part discusses an origin, properties and applications of investigated biopolyesters, and so the enzymology of their biodegradation. The experimental part deals with biodegradation of these polymers in liquid medium using several pure thermophilic bacteial strains and controlled composting of these bioplastics. Amongst six tested thermophilic bacterial strains only one showed PHB-biodegradation activity – strain Schlegelella thermodepolymerans. No degradation degree of amorphous or semi-crystalline PLA was observed. Mainly disintegration of both forms of PLA articles was observed in compost environment, thus the abiotic mechanism of its decomposition was indicated. After 4 weeks of composting, the relative weight loss of 99 % and 63 % was detected in amorphous and semi-crystalline PLA respectively. On the contrary, the weight loss of PHB after 4 weeks of composting reached 36 %, moreover, a half decrease of molar mass was observed using SEC. The surface erosive mechanism of PHB-biodegradation was stated using SEM. By monitoring of esterase, lipase and protease activities, no influence on the compost by polymer presence was concluded at statistical significance.
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A study of biodegradable polyesters based nanoparticles properties
Blažková, Jiřina ; Holas, Ondřej (advisor) ; Dittrich, Milan (referee)
10 ABSTRACT Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: PharmDr. Ondřej Holas, PhD. Student: Jiřina Blažková Title of thesis: A study of biodegradable polyesters based nanoparticles properties Nanoparticles (NPs) are particles with a diameter size ranging between 1 - 500 nm. They are preferably used as drug delivery systems or imaging systems. NPs are able to encapsulate both hydrophilic and hydrophobic drugs and also macromolecules such as peptides or mRNAs. The aim of this study was to specify selected properties of NPs prepared from poly (lactide-co-glycolide) polymer (PLGA) using polyvinyl alcohol as a surfactant. Nanoprecipitation was chosen as a preparation method. NPs were prepared from a branched PLGA copolymer and from a conventional linear PLGA polymer/oligomer. The main task was a stability study. The effect of the pH and the type of the used polymer of the nanoparticle suspension on the morphology of the nanoparticles was evaluated over one month period. The following parameters of nanoparticles with two model drugs (curcumin and procaine) were also monitored: encapsulation efficiency, drug loading and recovery yield. Dissolution tests were performer and the suitability of individual polymers for different types of drugs...
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Characterization of microorganisms with biodegradation potential for sulfonamides
Sedláček, Jan ; Palyzová, Andrea (advisor) ; Mikušová, Gabriela (referee)
Sulfonamides are antibiotics that are frequently used both in human and veterinary medicine. The combinations of abundant use of these antibiotics and their natural resistance to decay leads often to long term persistence in the environment. This accumulation, especially in living organisms, may lead to subsequent toxicosis. Also, presence of these antibiotic in nature poses problems with regard to the spread of genes for antibiotic resistance between potential pathogens. These facts led to an increase interest in studying the sulfonamide biodegradation and subsequent sulfonamide removal from the environment. In this work it was possible to isolate and characterize the microorganism Acinetobacter sp. strain 49. This microorganism was able to biodegrade under right conditions sulfamethoxazole with 80 % efficiency. Sulfamethoxazole is one of the most commonly found sulfonamide in the nature.
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Analysis of biodegradable polymers in soils
Paluchová, Natálie ; Řezáčová, Veronika (referee) ; Kučerík, Jiří (advisor)
Currently, there is a growing interest in usage of biodegradable polymers, regardless of their possible risk of generation of residues. The methods that are used for determination of residues usually include pre-treatment and are expensive and time consuming. Therefore, this bachelor thesis focuses on the development and verification of analytical method that would identify and quantify of biodegradable polymer residues in soils to eliminate the problems arising from sample pre-treatment. Therefore, thermogravimetry, which appears to satisfy the above conditions, was used for the analysis. The area of polymer degradation in three types of soils during thermal oxidation and the effect of polymer on soil during the analysis was investigated. Poly(3 hydroxybutyrate) was chosen to be the representative biodegradable polymer and there were two approaches used to its detection and quatification. The methods were tested for 6 concentrations of poly(3–hydroxybutyrate) (0,1; 0,5; 1; 2; 3; 5 %). The first approach concentrated on the usage of polymer analysis in the presence of a blank (without contaminat), which was subtracted from the blank. Using this method, the temperature interval of polymer degradation and weigh loss changes in this interval were observed. The second method focused on a soil universal model, that allows the identification and quatification of samples when the blank is not present. The blank is simulated by 19 equations, that allow the identification of intervals, in which degradation of samples occurs and also it provides the possibility to determinate the type of the polymer. However, the principle component analysis indicated that the method is sensitive to the type of soil and therefore it needs adjustments. Samples were incubated for 4 months, to verify the sensitivity of the method, in case of partial or complete decomposition of samples by soil microorganisms,. Thereafter, the concentrations of poly(3-hydroxybutryrate) in soil determined by respirometry and thermogravimetry were compared. The results indicated that accelerated degradation caused by poly(3-hydroxybutrylate) or contamination of the sample with the surrounding atmosphere during respiration may have occurred. Residual poly(3–hydroxybutyrate) was thermogravimetrically verified and results were compared to respirometry. According to the results it can be observed that there was an interaction between the soil organic matter and biota or contamination of the sample with the surrounding atmosphere. The results revealed, that there is a possibility of determination of biodegradable polymers in soils by thermogravimetric analysis. There are good results using the blank method, but it is limited by the existence of a blank. The method that is using the soil universal model (without blank) has a great potential in the future, but adjustments still need to be done.
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Kinetics of selected herbicides and their biodegradation in soil and water environments
Šabršulová, Anna ; Matoušková, Milada (advisor) ; Stibal, Marek (referee)
The three most commonly used herbicides in the Czech Republic (chloracetanilides, triazines and glyphosate) are also the herbicidal compounds found in the highest concentration in surface water. After agricultural application, they interact with soil and water due to their chemical properties and environmental factors affecting them. Adsorption coefficient, solubility in water environment, precipitation and drift have high impacts on the kinetics of these herbicides and degradates emerging from them. While moving through soil, parent compounds of mentioned herbicides are actively biodegraded by microorganisms, the most effective decomposers in nature. Biodegradation in soil and water environments is accelerated or slowed by temperature, moisture, quantity of microbial communities and many other environmental factors. Even if the microbial degradation is effective in a water or soil environment, there are many other new, arising compounds whose persistence in the environment is significantly higher than that of the parent compound. Degradates can end up in surface water by run off or wash out from agricultural fields and can remain there for decades depending on their chemical properties and natural conditions. Key words: surface water, herbicides, herbicides degradation products, rainfall-runoff...
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Biodegradation of lightweight polyurethanes in soil and subsequent analysis of their degradation products
Pražanová, Kateřina ; Innemanová, Petra (advisor) ; Cajthaml, Tomáš (referee)
According to the Waste Framework Directie 2008/98/ES and the Czech law on waste 185/2001 Sb., waste preienton is the main priority in waste management. Using biodegradable plastcs seems to represent a suitable approach in fulflling the strategy. The subject of this diploma thesis is biodegradable lightweight polyurethanes (PURs), which might represent suitable materials for repellent fences in agricultural landscapes. Biodegradaton processes are assumed to begin in the agricultural soil afer their lifetme. The biodegradability of new lightweight PURs (BIO 8-10), presented as material mineralizaton, was tested in agricultural soil under laboratory conditons according to the ASTM Internatonal standard method D5988-03. Afer the nine-month experiment the material with the highest biodegradability (BIO 10) containing starch (28 wt. %) was mineralized to 42.0 ± 4.2 %. Cellulose (the positie control) was completely mineralized; thus, the ialidity criterion (positie control mineralizaton > 70 %) was accomplished. Afer the biodegradability test, degradaton products (residual PURs) were separated from the soil by a two-step method using fuidisaton and fotaton, according to a modifed procedure described in Nuelle et al. (2014). The procedure enabled a subsequent analysis of PUR residues with Fourier transform...
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Optimization of polymeric nanoparticles separation and purification
Vencl, Jáchym ; Holas, Ondřej (advisor) ; Ondrejček, Pavel (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of: Pharmaceutical technology Consultants: Jana Kubačková, Ondřej Holas Student: Jáchym Vencl Title of Thesis: Optimization of polymeric nanoparticles separation and purification protocol Poly(lactic-co-glycolic) acid (PLGA) is one of the most successful polymeric molecule invented for biomedical use. PLGA's biggest advantage lies in its biodegradability and nontoxicityChyba! Záložka není definována.. It has been approved by EMA for human use. Because of increasing number of protein or nucleic acid based drugs the need for sophisticated drug delivery systems grows. PLGA nanoparticles (NPs) present exactly such drug delivery system capable of encapsulating large variety of compoundsChyba! Záložka není definována.. Within this study we have researched optimization of separation and purification of drug loaded NPs. They were prepared by nanoprecipitation of PLGAChyba! Záložka není definována.. Separation and purification of NPs was done using multiple cycles of centrifugation. We evaluated purification of particles prepared from five different PLGA polymers. Different centrifugation times were applied to find the most effective way. Water and two types of stabilizers each one in two concentrations have been used as purification...
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Microbial degradation of high-molecular polycyclic aromatic hydrocarbons
Bachmannová, Christina ; Cajthaml, Tomáš (advisor) ; Mikušová, Gabriela (referee)
Polycyclic aromatic hydrocarbons are anthropogenic pollutants of the environment that reprsent danger to human health. Thus, there is a great need for knowledge of their degradation mechnaims that could be utilized for bioremediation of the contaminated environment. Polycyclic aromatic hydrocarbons with higher molecular weight are rather insoluble substances with very low bioavailability and one of them i.e. benzo[a]pyrene was found to cause carcinogenic effects and other polycyclic aromatic hydrocarbons are potential carcinogens. In this thesis, I describe information of microbial degradation pathways of suspected carcinogens such as benzo[a]pyrene, benz[a]nthracene, dibenz[a]anthracene, benzo[k] fluoroanthene, benzo[b]fluoroanthene, chrysene and indeno[1,2,3-c,d]pyrene. I also discuss enzymes of degradation pathways, namely ring-hydroxylating dioxygenases, dihydrodiol dehydrogenases, ring-cleaving dioxygenases and their adaptations to catabolism of heavy polycyclic aromatic hydrocarbons. Key words: polycyclic aromatic hydrocarbons, Pseudomonas, biodegradation, benzo[a]pyrene
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