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The Application of Separation Techniques Based on Gas and Liquid Chromatography with Different Types of Detectors for the Determination of Biologically Active Compounds and Selected Xenobiotics
Mravcová, Ludmila ; Hajšlová, Jana (referee) ; Kráčmar, Stanislav (referee) ; Chýlková,, Jaromíra (referee) ; Vávrová, Milada (advisor)
This work deals with the using and application of separation techniques for analysis of polymers degradation and polycyclic aromatic hydrocarbons. Thereby this work is separated to two special parts. In the first part, the degradation properties of synthetic biopolymers based on lactic acid, gylcolic acid and poly(ethyleneglycol) PLGA-PEG-PLGA and ITA-PLGA-PEG-PLGA-ITA (modified by itaconic acid) were studied. These copolymers (firstly their thermosensitive hydrogels) should be used for therapy of fractures in orthopedy (as adhesives). Therefore, the sol-gel and gel-sol phase diagrams were determinated for selected samples of copolymers. The samples forming gel at 37 C was used for other study. Polymer samples were depredated in phosphate buffer at 37°C. The degradation process of physical hydrogels was described by the decrease of molecular weight and the increase of concentration lactic acid and glycolic acid in phosphate buffer. The obtained results confirmed that the degradation of polymer modified by itaconic acid is faster process than no modified polymer and polymers with lower ratio PLGA/PEG degrade also faster than lower ration PLGA/PEG. The influence of pH it was also tested. The rate of degradation of polymers was follow pH 4,0
PAH bond to nanoparticles of atmospheric aerosol: substrate specifity.
Bendl, Jan ; Hovorka, Jan (advisor) ; Cajthaml, Tomáš (referee)
Polycyclic aromatic hydrocarbons (PAHs) are reviewed including their chemical and chemical- physical features, their impact on health and the environment. Different behaviour of PAHs is mentioned. The detailed instruction for the measurement using high-volume cascade impactor BGI 900 (Hi-Vol) is described. Cleaning, equilibration, weighting, protection against contamination of the substrates and technique of the measurement were introduced. The experiment was done: under the last teflon back-up filter the extra PUF substrate was placed, where after the air exposition the significant amounts of gaseous phase of phenanthrene, anthracene, fluoranthene, pyrene and benzo(a)anthracene were captured. The extent of the volatile PAHs capture correlated positively with the vapour pressure (ranging from 10-4 to 10-1 Pa.). The other measured PAHs (coronene, benzo(ghi)perylene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene and indeno(1,2,3-cd)pyrene) with vapour pressure from 10-5 to 10-10 Pa were not captured. The experiment found out that polyurethane (PUF) substrates captured in noticeable amount the volatile phase of PAHs and therefore the correction for the capture of gaseous phase in the particle size fractions of PAHs was calculated. The deduction for the...
Study of main mycoremediation aspects - effect of bioavailability, biodegradation and toxicity of organic pollutants
Čvančarová, Monika
Many organic compounds are released to the environment and can be harmful to living organisms. These compounds are often persistent and toxic. Some are mutagens, carcinogens, endocrine disruptors or they can cause an increase in bacterial resistance. They tend to accumulate in nature and their transformation is a long-term process. Therefore, various remediation techniques are needed for decontamination. Remediation and bioremediation processes depend on many factors which should be critically evaluated. This dissertation thesis studies the relationship between bioavailability, biodegradation and toxicity of polychlorinated biphenyls, polycyclic aromatic hydrocarbons and fluoroquinolone antibiotics. These compounds of different origin, character and properties were degradated by ligninolytic fungi. Desorption behaviour of pollutants from historically contaminated sites, degradation potential of ligninolytic fungi, ongoing degradation mechanisms, transformation products and their toxicity were studied as important factors for evaluation of mycoremediation and its environmental impact. The results show that determination of bioaccessible fraction by sequential supercritical fluid extraction is very useful for precise prediction of biodegradability of pollutants. The evidence that ecotoxicity and...
The use of BEAS-2B cell line for micronucleus assay in genetic toxicology
Červená, Tereza ; Rössner, Pavel (advisor) ; Rubeš, Jiří (referee)
This thesis deals with the application of BEAS-2B cell line for micronucleus assay in genetic toxicology. It is divided into two main parts: a) theoretical introduction to the analysis and search for suitable models for testing the impact of air pollution and manufactured nanoparticles, b) practical part that describes the results of micronuclei induction by polycyclic aromatic hydrocarbons (PAHs), extractable organic matter (EOM) from diesel exhaust particles obtained from emissions of three types of fuel and engineered nanoparticles. BEAS-2B cell line is a nonmalignant human model of lung epithelium which seems to be suitable for micronucleus assay. This assay is commonly used for determining the genotoxicity of various substances to wide variety of cell cultures and also in human studies. In this thesis, the following substances were tested: benzo[a]pyrene, 3-nitrobenzanthrone and 1-nitropyrene as carcinogenic PAHs commonly found in polluted air; EOMs from exhaust particles of 100 % diesel fuel, a blend of diesel fuel and 30 % of biodiesel, 100 % biodiesel and two types of engineered nanoparticles (TiO2 and Ag). The cells were treated with the compounds for 28, 48 and 72 hours. The results confirm the suitability of BEAS-2B cell line as a model for testing the genotoxicity of substances under...
Study of main mycoremediation aspects - effect of bioavailability, biodegradation and toxicity of organic pollutants
Čvančarová, Monika ; Cajthaml, Tomáš (advisor) ; Kočí, Vladimír (referee) ; Bosáková, Zuzana (referee)
Many organic compounds are released to the environment and can be harmful to living organisms. These compounds are often persistent and toxic. Some are mutagens, carcinogens, endocrine disruptors or they can cause an increase in bacterial resistance. They tend to accumulate in nature and their transformation is a long-term process. Therefore, various remediation techniques are needed for decontamination. Remediation and bioremediation processes depend on many factors which should be critically evaluated. This dissertation thesis studies the relationship between bioavailability, biodegradation and toxicity of polychlorinated biphenyls, polycyclic aromatic hydrocarbons and fluoroquinolone antibiotics. These compounds of different origin, character and properties were degradated by ligninolytic fungi. Desorption behaviour of pollutants from historically contaminated sites, degradation potential of ligninolytic fungi, ongoing degradation mechanisms, transformation products and their toxicity were studied as important factors for evaluation of mycoremediation and its environmental impact. The results show that determination of bioaccessible fraction by sequential supercritical fluid extraction is very useful for precise prediction of biodegradability of pollutants. The evidence that ecotoxicity and...
Study of main mycoremediation aspects - effect of bioavailability, biodegradation and toxicity of organic pollutants
Čvančarová, Monika
Many organic compounds are released to the environment and can be harmful to living organisms. These compounds are often persistent and toxic. Some are mutagens, carcinogens, endocrine disruptors or they can cause an increase in bacterial resistance. They tend to accumulate in nature and their transformation is a long-term process. Therefore, various remediation techniques are needed for decontamination. Remediation and bioremediation processes depend on many factors which should be critically evaluated. This dissertation thesis studies the relationship between bioavailability, biodegradation and toxicity of polychlorinated biphenyls, polycyclic aromatic hydrocarbons and fluoroquinolone antibiotics. These compounds of different origin, character and properties were degradated by ligninolytic fungi. Desorption behaviour of pollutants from historically contaminated sites, degradation potential of ligninolytic fungi, ongoing degradation mechanisms, transformation products and their toxicity were studied as important factors for evaluation of mycoremediation and its environmental impact. The results show that determination of bioaccessible fraction by sequential supercritical fluid extraction is very useful for precise prediction of biodegradability of pollutants. The evidence that ecotoxicity and...
An acellular genotoxicity assay of complex mixtures of organic compounds bound on size segregated aerosols.
Fikejzlová, Monika ; Rössner, Pavel (advisor) ; Machala, Miroslav (referee)
The main aim of this work was to compare the genotoxicity of organic extracts from different size fractions of aerosol particles (1-10 µm, 0,5-1 µm, 0,17-0,5 µm) collected by high volume cascade impactors in various localities of the Czech Republic differing in the extent of the environmental pollution (Březno - strip mine, Dobré Štěstí - highway, Praha - city center, Láz - background station). Genotoxicity was determined in acellular assay of calf thymus DNA (CT-DNA) with and without S9 metabolic activation by analysis of DNA adducts induced by extractable organic matter (EOM) from the particulate matter (PM) by 32 P-postlabeling and the ability of extracts to induce oxidative DNA damage was evaluated using the competitive ELISA test. The main finding of this work is that most of the observed genotoxicity is connected with fine particles (<1 µm). The concentration of carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) in EOMs indicate that fine fractions bound the highest amount of c-PAHs in all sampling sites. This fact might be related to a higher specific surface of this fraction as compared with a course fraction and a higher mass as compared with a condensational fraction. As for aerosol mass, both fine and condensational fractions are effective carriers of c-PAHs. Similarly, the DNA...
PAH bond to nanoparticles of atmospheric aerosol: substrate specifity.
Bendl, Jan ; Hovorka, Jan (advisor) ; Cajthaml, Tomáš (referee)
Polycyclic aromatic hydrocarbons (PAHs) are reviewed including their chemical and chemical- physical features, their impact on health and the environment. Different behaviour of PAHs is mentioned. The detailed instruction for the measurement using high-volume cascade impactor BGI 900 (Hi-Vol) is described. Cleaning, equilibration, weighting, protection against contamination of the substrates and technique of the measurement were introduced. The experiment was done: under the last teflon back-up filter the extra PUF substrate was placed, where after the air exposition the significant amounts of gaseous phase of phenanthrene, anthracene, fluoranthene, pyrene and benzo(a)anthracene were captured. The extent of the volatile PAHs capture correlated positively with the vapour pressure (ranging from 10-4 to 10-1 Pa.). The other measured PAHs (coronene, benzo(ghi)perylene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(a)pyrene, dibenzo(a,h)anthracene and indeno(1,2,3-cd)pyrene) with vapour pressure from 10-5 to 10-10 Pa were not captured. The experiment found out that polyurethane (PUF) substrates captured in noticeable amount the volatile phase of PAHs and therefore the correction for the capture of gaseous phase in the particle size fractions of PAHs was calculated. The deduction for the...
The Application of Separation Techniques Based on Gas and Liquid Chromatography with Different Types of Detectors for the Determination of Biologically Active Compounds and Selected Xenobiotics
Mravcová, Ludmila ; Hajšlová, Jana (referee) ; Kráčmar, Stanislav (referee) ; Chýlková,, Jaromíra (referee) ; Vávrová, Milada (advisor)
This work deals with the using and application of separation techniques for analysis of polymers degradation and polycyclic aromatic hydrocarbons. Thereby this work is separated to two special parts. In the first part, the degradation properties of synthetic biopolymers based on lactic acid, gylcolic acid and poly(ethyleneglycol) PLGA-PEG-PLGA and ITA-PLGA-PEG-PLGA-ITA (modified by itaconic acid) were studied. These copolymers (firstly their thermosensitive hydrogels) should be used for therapy of fractures in orthopedy (as adhesives). Therefore, the sol-gel and gel-sol phase diagrams were determinated for selected samples of copolymers. The samples forming gel at 37 C was used for other study. Polymer samples were depredated in phosphate buffer at 37°C. The degradation process of physical hydrogels was described by the decrease of molecular weight and the increase of concentration lactic acid and glycolic acid in phosphate buffer. The obtained results confirmed that the degradation of polymer modified by itaconic acid is faster process than no modified polymer and polymers with lower ratio PLGA/PEG degrade also faster than lower ration PLGA/PEG. The influence of pH it was also tested. The rate of degradation of polymers was follow pH 4,0
Vliv fluoranthenu na růstové a vývojové procesy okřehku menšího (Lemna minor L.)
Hrušková, Zuzana
Polycyclic aromatic hydrocarbons (PAHs) are considered persistent organic pollutants because of the long persistence in the environment. The presence of PAHs significantly responds aquatic plant Lemna minor L. reduction of its growth, and thus represents a bioindicator of organic load of the aquatic environment. The aim of this thesis was to evaluate the influence of fluoranthene on growth and developmental processes Lemna minor L. During the 21 days were observed at several concentrations of fluoranthene (0.1, 0.5, 1 and 5 mg / l) growth and viability of plants, morphological and anatomical changes and growth parameters. We also investigated the ability of plant production and changes in the content of phytohormones (cytokinins, ethylene, ABA). The results showed that fluoranthene had a significant effect on the appearance of plants and production of biomass, specific leaf area and leaf dry matter content. The production capabilities were no significant adverse effects. Due fluoranthene increased production of ethylene, and abscisic acid formation in plants duckweed. After 21 days of culture was observed in the plants treated with low concentrations of fluoranthene to synthesize iP, iPR and Z.

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