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Possibilities of pesticide degradation by titanium dioxide
Píšťková, Veronika ; Veselý, Michal (referee) ; Vávrová, Milada (advisor)
The aim of this bachelor´s thesis is a selection of pesticides, which could be degradated using titanium dioxide. The first part of the paper deals with general pesticide characteristics, subdivision of pesticides, mode of action on target agents and transformations of pesticides within the environment – the metabolic and the non-metabolic tranformation. The second part of the paper deals with heterogeneous photocatalysis using semiconductor TiO2, which is activated by ultraviolet or solar radiation. Using this method pesticides could be transformed even into carbon dioxide, water and inorganic mineral salts. Furthermore, there are mentioned the factors, which affect degradation rate, analytical methods to determine kinetics of degradation and methods for monitoring transients and end products. By each group of pesticides there are stated the representatives from this group, which have been used for investigation of degradation methods. Furthermore are mentioned decomposition mechanisms of reaction and the intermediate products formed during the photocatalysis process.
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Multiresidual methods for the determination of pesticides in waters
Matušková, Monika ; Kubíčková, Kristýna (referee) ; Vávrová, Milada (advisor)
This bachelor´s work of theoretical character deals with multiresidual determination of pesticides in water. It is especially focused on pesticides generating residues in surface water, which - due to their toxicity and persistence in environment - require goal-directed monitoring. The division of pesticides is stated, and their properties, toxicity and elimination process are described in the work. Furthermore, possibilities of analytical determination, especially the methods of gas and liquid chromatography are introduced here. In the last chapter, the complete analytic procedure for determination of organochlorine pesticides is described.
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Pyrethroids in abiotic and biotic environmental matrices
Kociánová, Veronika ; Vondráčková, Ilona (referee) ; Vávrová, Milada (advisor)
Synthetic pyrethroids form the main class of synthetic organic insecticides, which are applied in agriculture, household, and public health. Synthetic pyrethroids account form more than 30% of insecticide use worldwide, thereby they gradual replace chemicals of insect pest control as organochlorine and organophosphate insecticides. Pyrethroids are synthetic derivates of natural pyrethrins. In comparison with natural pyrethrins have pyrethroids greater photostability, greater resistence to degradation and greater insecticidal activity. Pyrethroids are labeled as potent neurotoxicants, which interact with sodium channels. Pyrethroids occur in abiotic and biotic environmental matrices. In this study we focused on the determination of this compounds in environmental water samples by GC-ECD, because of the pyrethroids contain atoms of nitrogen and halogens in their structure.
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Degradation of pyrethroids using heterogeneous catalysts
Janík, Ondřej ; Bílková, Zuzana (referee) ; Vávrová, Milada (advisor)
This thesis was provided to study fotocatalytic degradation of polutants on the titanium dioxide, as modern eliminating method useful for removing of polutants out of the environmental matrix. There are also studied pyrethroids, as one of the most used pesticides in recent ages, and posibility of degradation of pyrethroids using degradation on titanium dioxide in aquatic system. This study contains an experiment of fotocatalytic degradation of pyrethroids on titanium dioxide in vitro with final analysis using GC-ECD.
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Výskyt patogenů a škůdců v porostu máku setého
Gabčíková, Rebeka
This work in its theoretical part deals with the basic characteristics of oilseed poppy cultivation, with a focus on the characterization of pests and diseases. The practical part of the work was conducted in the form of an experiment, which was carried out on the land of the company Agroregión a.s., based in Rajec, Slovakia. The experiment consisted of monitoring pests and diseases and evaluating the abundance of their occurrence in different variants of chemical treatment (control, insecticide, insecticide + fungicide). The occurrence of the black bean aphid (Aphid fabae) was detected among the pests, for which the direct impact of insecticidal treatment on the abundance could not be demonstrated. The occurrence of poppy downy mildew (Peronospora arborescens) was confirmed among the diseases, and the results in the form of the percentage of affected plants proved to be an insufficient measure for the evaluation of the disease progress. However, from the attached photographs, it is apparent that fungicidal protection in this case provided significantly better plant health.
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Akutní a chronické působení neonikotinoidových látek na vodní organismy
STROUHOVÁ, Alžběta
Neonicotinoids, synthetic substances derived from the natural alkaloid nicotine, are one of the newest class of pesticides. Neonicotinoids are selective for invertebrate nicotinic acetylcholine receptors (nAChRs) and are widely used to treat crops around the word. The aim of this study was to evaluate acute and chronic toxicity of neonicotinoid substance acetamiprid and neonicotinoid product Mospilan 20 SP, which contains 20 % of acetamiprid, to aquatic organisms. Chronic effects to the biochemical profile of haemolymph, oxidative stress biomarker and antioxidant biomarkers have been evaluated too. Marbled crayfish (Procambarus virginalis) was used as a model organism to provide the toxicity. The acute toxicity (96hLC50) of the pure neonicotinoid substance acetamiprid to marbled crayfish is 0.8 mg.l-1, of Mospilan it is 2.71 mg.l-1. The theoretical acute toxicity of Mospilan is 4.0 mg.l-1. It was calculated based on the acute toxicity of pure acetamiprid as the active substance of Mospilan. Additives in the preparation probably contributes its toxicity more than the active substance itself. Acetamiprid and Mospilan impact on changes in the levels of biomarkers of the biochemical profile of haemolymph, biomarker of oxidative stress and antioxidant biomarkers. Changes in the levels of biomarkers are already manifested at concentrations corresponding to 0,1 % and 1 % of 96hLC50. These changes include increases in GLU, AST, ALT and LDH levels, decreases in CAT and GST activity and changes in LPO level.
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Vliv koncentrace, teploty a doby působení na biochemické parametry raka mramorovaného (Procambarus fallax f. virginalis) exponovaného neonikotinoidovému pesticidu, thiaklopridu
HUMMELOVÁ, Světlana
The aim of this work was to evaluate the effect of concentration, water temperature conditions and duration of action of thiacloprid on biochemical parameters of marbled crayfish (Procambarus virginalis). The time of this experiment was taken for 56 days (28 days of exposure and 28 days of depuration). Crayfish were divided into groups according to selected concentrations: control group without thiacloprid (K), highest detected environmental concentration 4.5 ?g?l-1 (TEN) and concentration 64.6 ?g?l-1 (TLC) (10 % of the 96-hour lethal concentration for marbled crayfish) and different water temperatures (17 and 23 °C). Crayfish, which was exposed to a lower water temperature conditions (17 °C) during the experiment, have been generally shown lower activity in behaviour against crayfish exposed to a higher temperature (23 °C). The effect of concentrations of thiacloprid (4.5 and 64.6 ?g?l-1) caused in the muscle and hepatopancreas LPO and changed GST activity. Statistically significantly (P<0.01) changes were observed in all tissues (muscle, hepatopancreas and gills), caused by effect of concentrations of thiacloprid (4.5 and 64.6 ?g ? l-1) and temperature condition (17 and 23 °C) during the experiment in SOD, CAT and GSH. The effect of thiacloprid concentration, water temperature condition and duration of action caused in haemolymph significantly (P<0.01) increase in GLU, NH3, AST, ALT and CK. Other parameters in haemolymph (LDH, TP, Ca2+, Mg2+) were affected only by the water temperature condition. Crayfish in higher water temperature condition (23 °C) showed higher values of these indicators in opposite to crayfish in colder temperature condition (17 °C). No different changes in haemolymph were observed only in two parameters (ALB and GLOB). The highest statistically significantly (P <0.05) changes of individual parameters inside each one group were observed especially after 14 and 28 days of exposure. Especially in higher concentration of thiacloprid and temperature was found that 28 days of depuration time was not sufficient to balance biochemical parameters to normal control values. At the end, it is apt to mention that water temperature condition had influence on individual parameters themselves, when in several cases different values of monitored biomarkers were measured between temperatures in groups exposed to the same concentrations of thiacloprid, even though their control groups showed no differences between temperatures. The results of this work confirm the synergistic effect of thiacloprid, temperature and duration of action on non-target aquatic organisms and could be used for other studies to evaluate the effect of thiacloprid and other pesticides on organisms.
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Chemical and biological control of phlebotominae sand flies
Pružinová, Kateřina ; Volf, Petr (advisor) ; Král, David (referee)
Phlebotominae sand flies (Diptera: Phlebotominae) are important vectors of leishmaniasis. Control measures are complicated by the fact that sand fly breeding sites and resting places are generally hard to find. Measures used to control adult sand flies include the use of chemical insecticides for insecticide-treated bednets or curtains, residual spraying of dwellings, eventually the space-spraying. Domestic dogs as reservoir host of visceral leishmaniosis can be protected by dog-collars impregnated with insecticides or by spot on application of insecticides. Chemical insecticides may be toxic for non-target organisms and the increase of insecticide-resistance of some sand flies populations is possible. Therefore, new methods of biological control should be tested; entomopathogenic organisms (Bacillus sphaericus, B. thuringiensis, Beauveria bassiana), pheromone-baited traps and noxious plants could be used. Hormone TMOF, inhibitor of trypsin biosynthesis, was successfully tested in mosquitos. Based on similarity of mosquitos and sand flies, the effect of this peptide on blood digestion and egg development is tested in Phlebotomus and Lutzomyia species.
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Development of insecticides inhibiting acetylcholineseterase
Mányová, Brigita ; Vopršalová, Marie (advisor) ; Maixnerová, Jana (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmacology & Toxicology Student: Brigita Mányová Supervisor: PharmDr. Marie Vopršalová, CSc. Supervisor-specialist: PharmDr. Vendula Hepnarová, Ph.D. Title of diploma thesis: Development of insecticides inhibiting acetylcholineseterase Pest insects cause problems and damage all over the world. They are vectors of serious diseases such as malaria, dengue fever, yellow fever, Zika virus disease and chikungunya disease. They cause huge damage to agricultural crops and are annoying to everyday life in living spaces. The aim of this diploma thesis was in vitro testing of selected compounds from the group of bis-isoquinoline and bispyridinium acetylcholinesterase inhibitors as potential insecticides. Another goal was also to create relationships between structure and effect. The ability of these compounds to inhibit both human (hAChE) and fly acetylcholinesterase (MdAChE) was evaluated. The modified Ellman spectrophotometric method was used. The half inhibitory concentration (IC50) values were obtained for both enzymes and the selectivity indexes (SI) were then calculated. Compounds having IC50s in micromolar or nanomolar range and exhibiting selectivity for MdAChE were most desirable. During the testing of these inhibitors, three...
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