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Activities of enzymes involved in transformation of polycyclic aromatic hydrocarbons during composting
Šírová, Kateřina ; Cajthaml, Tomáš (advisor) ; Dračínská, Helena (referee)
Polycyclic aromatic hydrocarbons (PAHs) are recalcitrant organic pollutants, which occur widely in the environment. Some of these compounds are carcinogenic and toxic, many studies therefore focus on suitable remediation technologies. It has been shown that composting is an efficient treatment for contaminated solid matrices. Changes in several enzyme activities during co-composting of PAH-contaminated soil were studied in this thesis. The total initial concentration of analyzed PAHs in the soil was 1065 ± 86 µg·g-1 . The chosen activities represented well-known key enzymes involved in the transformation of PAHs or catechol as the central metabolite of PAH microbial degradation. At first, a method for extraction of the selected enzymes from the compost matrix was optimized. This approach was then used for the extraction of the enzymes from compost samples collected at each phase of composting. The activity of manganese peroxidase, laccase, tyrosinase and catechol-2,3-dioxygenase was detected during the cooling and the maturation phase. The only detected activity during the initial mesophilic phase was that of manganese peroxidase. The activities of catechol-1,2- dioxygenase and lignin peroxidase were not detected at all. Despite the fact that PAHs were substantially degraded, no influence of PAHs...
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Determination of content of organic compounds in biochar
Novotná, Martina ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Biochar is created during the pyrolysis of organic biomass. Once added into the soil, it can improve its features. Biochars made from sewage sludge have various compositions. It is because of the vast difference between entrance materials. Organic pollutants can be absorbed into its surface during the cooling proces sof pyrolysis. If released into the enviroment, these compounds can cause inhibition of plant growth, get into food chains and adversely affect living organisms. Organic pollutans are determined most often by GC/MS after organic solvent extraction.
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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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Vliv polycyklických aromatických uhlovodíků na růst a bioenergetiku rostlin
Francová, Jana
This work summarizes current knowledge of polycyclic aromatic hydrocarbons (PAHs) and their plant uptake. PAHs as subcategory of persistent organic pollutants (POPs) represent an important group of environmental pollutants. Many of them are toxic, carcinogenic or mutagenic. The plants comprising the essential part of terrestrial and aquatic ecosystems, are able to absorb these compounds from environment thus become the significant source of PAHs for all animals including human.In the screening experiment I found stressful appropriate concentrations of PAHs - fluoranthene (FLT). In pea plants I watched the growth of the aerial parts and roots and appropriately I measured data compiled.
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Variabilita procesu uzení ve vztahu k druhu mas a masných výrobků
Holčíková, Radmila
The topic of my bachelor thesis is Variability of smoking process in relation to the type of meat and meat products. The first part of work describes history of smoking, then the work is dedicated to the composition of smoke and his negative and positive properties. In the next section there are described types of smoking and machines needed to this process. Then the work focuses on use of salt, colorations and changes during smoking. The last part deals with the distribution of meat products and factors affecting smoking time and temperature. There are mentioned polycyclic aromatic hydrocarbons which cause negatively on human health.
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Růstová a metabolická odezva okřehku menšího (Lemna minor L.) na polycyklický aromatický uhlovodík
Hrušková, Zuzana
Polycyclic aromatic hydrocarbons (PAHs) are ranked among the organic compounds with long-term permanence pollute the environment. The presence of PAHs react particularly aquatic plants. Duckweed (Lemna minor L.), water plant characterized in that it is exposed to foreign substances significant portion of his body, is a suitable model for the study of plant developmental and metabolic responses to the presence of polycyclic aromatic hydrocarbons. The aim of the thesis was to observe developmental and metabolic responses duckweed on the effect of polycyclic aromatic hydrocarbon fluoranthene. For 21 days were observed in four concentrations of fluoranthene, which accounted for commonly occurring (0.1 and 0.5 mg FLT / l) and slightly increased (1 and 5 mg FLT / L) concentrations of fluoranthene, metabolic and bioenergetic response. We were also observed growth and developmental changes and changes in the content of phytohormones. The study was focused on plant morphology. The results of this work, was evident that the presence of FLT has a significant impact on the appearance and production plants. It was also demonstrated a significant negative impact on the growth parameters. Fluoranthene demonstrated significant effects on the production of plant hormones.
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The Use of a Simple Electrochemical DNA Biosensor for the Determination of Environmental Pollutants and Investigation of Their Interaction with DNA
Blašková, Marta ; Vyskočil, Vlastimil (advisor) ; Zima, Jiří (referee)
The interaction between three selected representatives of environmental pollutants - naphthalene, anthracene, and 2-aminoanthracene - and DNA was investigated using an electrochemical DNA biosensor based on a glassy carbon electrode (GCE) and low molecular weight DNA from salmon sperm (DNA/GCE). The interactions with DNA were monitored using square wave voltammetry (SWV) and electrochemical impedance spectroscopy (EIS). For naphthalene, there was no DNA damaging interaction observed. In the case of anthracene, the formation of an intercalation complex [DNA-anthracene] was observed. However, its formation does not cause DNA strand breaks. The formation of similar intercalation complex was observed for 2-aminoanthracene [DNA-2-aminoanthracene], where we suppose on the basis of the results obtained that the intercalation of 2-aminoanthracene into the DNA double helix induces a tension and subsequent formation of single-strand breaks, which cause that the fragments of DNA fall away from the electrode surface. The intercalative interaction of DNA with anthracene a 2-aminoanthracene was used in the development of electrochemical methods for determination of these compounds at the GCE and DNA/GCE. At the development of the methods, DC voltammetry (DCV) and differential pulse voltammetry (DPV) were used....
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Role of benzo[a]pyrene in cancer development
Vaňátková, Petra ; Moserová, Michaela (advisor) ; Kubíčková, Božena (referee)
4 ABSTRACT Cancer is nowadays one of the most serious diseases. Tumor development is a multistage process in which the effect of internal and external factors lead to failure of regulatory and defense mechanisms of the organism and to the accumulation of mutations which are generated by these organisms. Chemical carcinogens and also biological and physical factors can be regarded as the main external factors. Polycyclic aromatic hydrocarbons are large group of chemical carcinogens. One of them, benzo[a]pyren is the most studied polycyclic aromatic hydrocarbon. Carcinogenic, mutagenic and teratogenic effects of benzo[a]pyrene had been shown on laboratory animals. Benzo[a]pyrene is considered as the main carcinogen in tobacco smoke and is connected with lung cancer development among smokers. Benzo[a]pyrene is metabolized in activation or detoxication pathways by enzymes of mixed function monooxygenase systeme of cytochromes P450. The most important enzymes involved in the activation of these compounds are CYP1A1 and CYP1B1 with cooperation of epoxide hydrolase. The reactive species generated in its activation pathway are able to form covalent adducts with DNA. The most important carcinogenic product of benzo[a]pyrene is benzo[a]pyrene-7,8-dihydrodiol-9,10-epoxide, which can caused irreversible ganges in...
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Detailed characterization of pyrolysis oil by separation techniques and mass spectrometry
Žvaková, Veronika ; Mravcová, Ludmila (referee) ; Čáslavský, Josef (advisor)
The aim of this work is detailed characterization of pyrolysis oil by advanced analytical separation methods and mass spectrometry. During the pyrolysis process decomposition of complex organic material take place in the presence of high temperatures and the absence of oxygen. Condensable part of vapours and aerosols forms viscous liquid called pyrolysis oil which is a complex mixture of large amount of compounds. In this work samples from microwave pyrolysis of woodchips and sewage sludge from wastewater treatment plant Brno-Modřice were analysed. Samples were provided by Bionic Laboratories company. Samples were separated by column chromatography on activated silica. For detailed characterization of each fraction gas chromatography with mass spectrometry detection and comprehensive two-dimensional gas chromatography with mass spectrometric detection with time of flight analyser were used. Substances that have been identified can be divided into several groups: alkanes, alkenes, aromatic hydrocarbons, polycyclic aromatic hydrocarbons, alcohols, aldehydes, esters, carboxylic acid and heterocycles.
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