|
|
Determination of pesticides in solid environmental matrices
Řepková, Michaela ; Komendová, Renata (referee) ; Mravcová, Ludmila (advisor)
The bachelor thesis deals with the still pressing issue of pesticides in the soil environment. The theoretical part deals with the entry of these pesticide substances into the environment, i.e. their application in various forms to agricultural soil, where they are retained in the soil based on certain factors and subsequently transported from the soil to other components of the environment. As pesticide residues are also present in other parts of the environment, they represent a global problem because of the potential environmental and health risks not only for the human population. Furthermore, the theoretical part deals with the appropriate method for the determination of these pesticide substances in the soil matrix, both a suitable extraction method and a suitable analytical technique. The experimental part primarily focused on the actual determination of these persistent organic pollutants. Pesticides from soil were extracted by one of the most popular extraction methods at present, namely the QuEChERS method. This method has been thoroughly optimised to achieve the lowest possible detection/quantification limits, the highest possible recoveries and good repeatability. The LC-MS/MS method was chosen as the appropriate analytical method for the determination of pesticides in soil extracts.
|
|
|
Optimization of methods for the analysis of pharmaceuticals residues in different crops
Súkeníková, Kamila ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
Aim of this thesis is to optimize the extraction method for extracting pharmaceuticals from various types of matrices. Presence of pharmaceuticals in the environment represent an increasing problem, even though they are only found in low concentrations. Therefore, great emphasis is placed on their analysis. Since the concentration of pharmaceuticals is often low and their chemical diversity is large, their analysis presents a significant challenge. For this reason, this thesis is focused on optimizing the extraction method from plant matrices. This optimization is carried out in order to obtain the best possible extraction method, and thus ensuring the highest possible yield of pharmaceuticals from radish, carrot, and mustard matrices. The optimization of the extraction method involved finding the parameters for individual steps of the QuEChERS extraction method that showed the best average yield for all pharmaceuticals.
|
|
|
Study of the use of crops for phytoremediation of contaminated soil by pharmaceuticals
Hamplová, Marie ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
Pharmaceuticals leaking into the environment from wastewater and livestock farms raise concerns about the impact on the ecosystem and human health. Residues of pharmaceuticals present in soil are subject to a number of biotic and abiotic processes, including uptake, translocation and accumulation by plants. The ability of plants to accumulate or degrade pharmaceuticals could have potential applications in the process of 'phytoremediation', where plants and their associated micro-organisms are used to stabilise, degrade or remove contaminants from the environment. In the framework of this thesis, experiments on phytoremediation of drug-contaminated soil by the cover crop oilseed radish (Raphanus sativus L. var. Oleiformis) under controlled conditions were conducted. Soil samples were extracted by ultrasonic extraction, plant samples by QuEChERS method and the final analysis of drugs was performed by UPLC-MS/MS. Oilseed radish produced a large amount of aboveground biomass compared to the other two crops and the presence of drugs had no negative effect on its growth. However, the determined levels of each drug in the soil and in the crop showed insufficient effectiveness of phytoremediation. The accumulation of drugs by the crop was low except for residues of the antidepressant venlafaxine. Therefore, according to these results, oilseed radish is not a suitable crop for phytoremediation of drug-contaminated soil. Experiments were also carried out with the root vegetable radish (Raphanus sativus L. var. Sativus) and carrot (Daucus carota L.) to assess the risk to human health associated with the accumulation of drugs in vegetable roots. The risk has not been demonstrated in terms of the amount of established drugs in the roots. Only the metabolite clofibric acid accumulated to a higher extent and the antibiotic trimethoprim was the most translocated to the aerial parts of the crop. The rate of uptake and translocation of drugs by the plant depended on many factors, as their content varied considerably between drug groups and between parts and types of crops.
|
|
|
Use of the QuEChERS method for the analysis of fluoroquinolone antibiotics in soil
Brabcová, Kristýna ; Zlámalová Gargošová, Helena (referee) ; Mravcová, Ludmila (advisor)
The content of this master's thesis is an application of frequently used extraction method QuEChERS on soil or other samples like litter or manure containing fluoroquinolone antibiotics. In the theoretical part of this thesis are chapters describing drugs, antibiotics and antibiotic resistance. Fluoroquinolones are described in more details with their properties, appearance and behaviour in the environment. The last chapter is focused on analytical methods. In the experimental part of this thesis is chosen in accordance with available publications the most suitable extraction method. This method is tested and optimized on soil samples. The optimized method is applied on the real soil and poultry litter samples to determine the amount of ciprofloxacine and enrofloxacine. This extraction method is used on other fluoroquinolone antibiotics (norfloxacine, ofloxacine, pefloxacine, moxifloxacine) in soil. All of the samples were analyzed by LC-MS.
|
|
|
Application of Mass Spectrometry for the Determination of Oxidative Stress Markers and Mycotoxins
Čumová, Martina ; Večeřa, Zbyněk (referee) ; Hajšlová, Jana (referee) ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
The first topic presented in the dissertation thesis is determination of isoprostanes as markers of oxidative stress and other compounds affected by presence of oxidative stress. Isoprostanes iPF2-III, iPF2-VI, iPF2-VI, astaxanthin and polyunsaturated fatty acids (PUFA), especially arachidonic acid (AA) were monitored in Atlantic salmon eggs (Salmo salar). Methods for the determination of these compounds have been developed and optimized using chromatographic separation coupled to conventional or mass spectrometric detection. Freshly laid eggs, eyed embryos and non-viable eggs were used to test a general hypothesis that egg viability can be affected by susceptibility to oxidative stress, either through the specific fatty acid concentration and/or the antioxidant capacity of the eggs. Levels of isoprostanes and arachidonic acid (AA) were significantly higher in non-viable eggs than in control (eyed embryos) as well as relative abundance of PUFA. While no difference of isoprostanes was found between freshly laid and control those from the Atlantic stock except iPF2-VI which was observed under the LOQ in the control. Higher levels of PUFA and AA in comparison with the control were observed in the freshly laid eggs. However, the only statistically significant difference was observed in the amount of astaxanthin. Different levels of PUFA and astaxanthin may be related to their biochemical consumption during the development of eggs. This work evaluated potential effect on the viability of eggs Salmo salar due to the presence of oxidative stress. The monitoring of mycotoxins in food and feed was the subject of the second topic. Mycotoxins are secondary metabolites produced by fungi. They are ubiquitous undesirable natural contaminants that are toxic for humans and animals. Today are known more than 500 mycotoxins. However, only few of them are regulated by the European Union. The European Food Safety Authority (EFSA) was asked by the European Commission to provide a scientific opinion on other mycotoxins for which statutory limits could be developed. In this study is proposed simultaneous screening allowing fast, reliable and sensitive approach, identification and quantification of 17 mycotoxins in food and feed sample. The method includes both mycotoxins regulated by the EU and selected mycotoxins required by the EFSA (aflatoxins, deoxynivalenol, nivalenol, zearalenone, fumonisin, ochratoxin A, T-2 toxin, HT-2 toxin, enniatins and beauvericin). Analytes are isolated by the modified QuEChERS method. For separation and target mycotoxins detection, ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC –MS/MS) was employed. The method also allows determination of ergot alkaloids (ergocornine, ergosine, ergocryptine, ergocristine and their respective epimers). The developed method was used either for monitoring mycotoxins and ergot alkaloids in feed and raw materials and barley and malt prepared from it.
|
|
|
The application of pollen as bioindicator of the environmental state
Marečková, Kateřina ; Vávrová, Milada (referee) ; Čáslavský, Josef (advisor)
Pesticides and their excessive use lead to environmental pollution. Violation of the guidelines for their use disposal of empty containers could lead to contamination of water, soil and poisoning of animals and beneficial insects. Honey bee is useful creature on our planet. Good farming depends entirely on the pollination, but whole vegetal kingdom couldn’t exist it form known and used by mankind. Therefore, rules that protect these useful creatures against inadequate use of pesticides have been developed. This study focuses on the evaluation of the possibility to use bee products as bioindicators of the state of environment. Five active substances which are components of pesticides used in the treatment of agricultural field around Tasovice village were analysed in the pollen and honey. For sample preparation QuEChERS and SPE methods were used, gas chromatography with to mass spectrometric detection was employed as final analytical technique.
|
|
|
Analysis of pesticides in the environment using the QuEChERS method
Vašinková, Alena ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis focuses on pesticides in the environment, more specifically in cereals. Pesticides were monitored in various samples of cereals (barley, rye, oats, and wheat) within the thesis. The monitored substances were isolated in selected samples and concentrated using the QUECHERS method. Gas and liquid chromatography were used to determine pesticides. The theoretical part consists of the common types of pesticides, divided by the ease with which these substances into food and their impact on humans and environment. It also mentions current health protection legislation and environmental legislation.
|
|
|
Analysis of drugs in the earthworms using the QuEChERS method
Navrkalová, Jitka ; Kučerík, Jiří (referee) ; Mravcová, Ludmila (advisor)
The content of this Bachelor‘s thesis is an analysis of pharmaceuticals in earthworms using the QuECHERS method followed by the LC-MS/MS analysis. The theoretical part focuses on the specific groups of used drugs, their properties and applications. Furthermore, it focuses on the occurrence of drugs in the environment from their input to the negative consequences including the impact on earthworms. The theoretical part also discusses the QuEChERS method and liquid chromatography with mass spectrometry. At first in the experimental part, the QuEChERS method (concretely parameters like organic solvent, aqueous phase composition, amount of EDTA, purification method) was optimized for the extraction of 31 drugs from earthworms analytically completed by LC MS/MS. This optimized and validated method is subsequently applied to the extraction of drugs from earthworms from the performed experiments. The experiments focus on the effect of drug concentration in soil and the presence of biochar on the uptake of different drugs by earthworms.
|
|
|
Study of drugs intake by lettuce
Amrichová, Anna ; Zlámalová Gargošová, Helena (referee) ; Řezáčová, Veronika (advisor)
The aim of this thesis is to analyze the content of selected groups of drugs in cultivated lettuce. The theoretical part includes a chapter dedicated to the drugs used, their use, physicochemical properties, and their impact on the environment. Other chapters focused on analytical methods for determining drugs, hydroponic cultivation of lettuce, and some parameters of ecotoxicological tests. The experimental part began with the optimization of the QuEChERS extraction procedure. The optimized procedure was then applied to hydroponically grown samples of roots and leaves of lettuce containing selected groups of drugs, which were subsequently analyzed using liquid chromatography – mass spectrometry. The experimental part also addressed the ecotoxicological impact of different drug concentrations on hydroponically grown lettuce.
|
|
|
Analysis of pesticides in the environment using the QuEChERS method
Vašinková, Alena ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
This thesis focuses on pesticides in the environment, more specifically in cereals. Pesticides were monitored in various samples of cereals (barley, rye, oats, and wheat) within the thesis. The monitored substances were isolated in selected samples and concentrated using the QUECHERS method. Gas and liquid chromatography were used to determine pesticides. The theoretical part consists of the common types of pesticides, divided by the ease with which these substances into food and their impact on humans and environment. It also mentions current health protection legislation and environmental legislation.
|
guest ::
