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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.
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Content of rutin in selected elderberry cultivars
Píšťková, Magdalena ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
The aim of this diploma thesis was to determine the rutin content in springs and leaves of 19 elderberry species (Sambucus nigra L.) with use of liquid chromatography. Furthermore the rutin content was determined in its significant sources – rue and buckwheat. The observed values were compared in order to answer the question whether it is useful to use the elderberry spring and leaves as a new source of rutin. Theoretical part of the thesis describes elderberry in general, its chemical composition and its usage in medicine. Following part concentrates on important substances contained in elderberry – flavonoids. Also principles of extraction techniques and HPLC are discussed. In practice the rutin was gained from plant matrix with use of pressurized hot water extraction (PHWE) which was performed in three five minutes long cycles. Conditions during the PHWE were set up to 80 °C and 150 bars. Obtained extract was purified with use of SPE columns and analyzed by HPLC with DAD detector (wave length – 360 nm). HPLC was performed with SUPELCOSILTMLC-8DB column. The mobile phase was composed of MeOH, H2O, and HCOOH in ration of 36:61,5:2,5. The set up flow of mobile phase was 1 ml/min. In the leaves the highest rutin content was determined in Pregarten – 26,34 ± 0,50 mg/g. On the other hand the lowest rutin content in leaves was determined in Körsör – 3,74 ± 0,13 mg/g. In springs the obtained results were as follow. The highest content was determined in Samyl – 4,87 ± 0,01 mg/g and the lowest content was determined in Heidegg 13 springs – 0,56 ± 0,01 mg/g. Also the HPLC detection limit – 6,3 . 10-5 mg/ml and quantitation limit – 2,1 . 10-4 mg/ml were determined for rutin.
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The use of GC/MS for the analysis of drugs
Sýkora, Richard ; Opatřilová, Radka (referee) ; Vávrová, Milada (advisor)
This diploma thesis is based on the current issue of the presence of pharmaceuticals in various components of the environment. Concerning the contamination by residues of pharmaceuticals the most affected environment is the aquatic environment where these substances leaks especially from wastewater treatment plants, which eliminate them during the cleaning process only partially. This work is focused on the selected group of pharmaceuticals, non-steroidal anti-inflammatory drugs (salicylic acid, ibuprofen, caffeine, naproxen, ketoprofen, diclofenac) in waste water. For analysis purposes two types of sampling were used and compared: the conventional spot sampling of wastewater and the sampling using passive samplers POCIS. The sampling took place at the inflow and outflow of the wastewater treatment plant in Brno Modřice. The solid phase extraction (SPE) using Oasis HLB columns was used as the extraction method. Extracted sample was derivatized then. Derivatization agents were: MSTFA (N-methyl-N-(trimethylsilyl)trifluoroacetamid) and BSTFA (N, O-bis(trimethylsilyl) trifluoroacetamid). The final analysis was performed using gas chromatography with mass spectrometric detection Time-of-Flight (GC/TOF-MS).
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Extraction of selected elderberry flavonoids for food industry purposes
Grulichová, Hana ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
Amount of rutin and quercetin in bark and leaves from different type of Sambucus nigra was determined in this diploma thesis. Records of amounts were compared with amounts in significant sources of these flavonoids. Matters from raw matrix were obtained with pressurized solvent extraction (PSE) and pressurized hot water extraction (PHWE). There was use temperature 120°C, pressure 150 bar, three times 5-min cycles for PSE. There were used 80°C, 150 bar, three 5-min cycles for rutin extracted with PHWE and the same condition were used for extraction of quercetin only the temperature was changed to 100 °C. Analysis of rutin and quercetin were carry out high performance liquid chromatography (HPLC) with diode array detection (DAD), where was used SUPELCOSILTM LC 8DB column (5µm; 250 x 4.6 mm). Methanol: water: formic acid (36: 61.5: 2.5, pH 2.17 2.28) was used like a mobile phase. The flow of the mobile phase was set up 0.7 ml/min. Size of sample was 10 µl. The most amount of rutin was determined in the leaves of wild kind of Sambucus nigra with methanol extraction and hot water too. Extraction with PHWE was more effectively. There were determined 5.58 mg of rutin in one gram of sample from wild Sambucus nigra. There were determined the smallest amount of rutin in Sambucus nigra Körsör. There was found only 0.13 mg/g with extraction PHWE. The quercetin wasn’t determined in any Sambucus nigra leaves. There were found both of the flavonoids (rutin and quercetin) in the branch of Sambucus nigra. The rutin was determined in the small amount in wild kind but it was found in the important amount in Sambucus nigra cultivar. Whereas the quercetin was found in higher concentration than rutin when was finding the ideal conditions for extraction of branch. The quercetin was chosen like more important in light of amount. In the end the quercetin wasn’t detected in any Sambucus nigra cultivars. The most amount of quercetin was determined in wild sambucus nigra, 0.24 mg/g. The most amount of rutin was found in Sambucus nigra Albida, 2.33 mg/g.
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Determination of residues of the selected pesticide effective substances in wine using the GC/MS method
Ehrenbergerová, Martina ; Benešová, Karolína (referee) ; Mikulíková, Renata (advisor)
The grape is one of the oldest cultivated plants. It can be consumed as a fruit or it can be used as a raw material for making stews, juices or the cultivated drink – wine. Generations of wine-makers have been striving to improve both the cultivating conditions of vineyards and the quality of wine. Many harmful elements, such as herbivorous pests, diseases and storms are important factors that can have a negative impact on crop quality. To regulate the effects of these factors, an integrated protection system is used, incorporating agronomical measures, resistant varieties and a wide spectrum of pesticides. However, increasing the usage of pesticides brings certain dangers to both the production quality and the environment. This necessitates the monitoring of the negative effects, including the content of pesticide residues in the grapes. My thesis studies and experimentally assesses selected pesticide residues in certain wine samples.
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The assesment of chloramphenicol residues in biological material, water and feed by GC/MS
Lukačková, Dagmar ; Šalplachta, Jan (referee) ; Rejtharová, Martina (advisor)
This diploma thesis addresses the presence and determination of chloramphenicol residues in biological materials. The theoretical part presents the literature retrieval containing information about veterinary medicaments with the banned use in food producing animals and also the sum of the legislative requirements concerning the presence of these substances in foodproducts and raw food materials of animal origin. The comparison was carried out between the existing analytical methods used for the determination of chloramphenicol residues in different biological materials, which are altogether based on the solid phase extraction for the extract cleaning and the new procedures for sample preparations using columns where the sorbent performs on the molecularly imprinted polymers principle.
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Application of gas chromatography for determination of drug residuals
Sýkora, Richard ; Lisá, Hana (referee) ; Vávrová, Milada (advisor)
Analgesics are nowadays widely used group of drugs in human and also in veterinary medicine. Residuals of these drugs enter surface waters via discharges from the waste water treatment plants as the result of insufficient efficiency of their removal during cleaning process. In this bachelor thesis the possibilities of the analgesics residuals determination in waters using derivatization followed by gas chromatography with mass spectrometric detection were experimentally evaluated. Individual derivatization procedures were compared too. Several derivatization agents were tested and experimental parameters for selected analgesics were optimized (reaction time and temperature, amount of derivatizing agent). Further, several procedures of isolation of target compounds from water based on Solid Phase Extraction were verified. In all cases, gas chromatography with TOF-based mass spectrometric detection acts as final analytical method.
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Multirezidual analysis of selected pesticides in barley
Ehrenbergerová, Martina ; Duroňová, Kateřina (referee) ; Mikulíková, Renata (advisor)
Barley is one of the economically important crops. Its production is primarilly used as fodder barley and also in brewery and food industry. Particularly the part of its production intended for malt production must be of high quality. There are some important factors which can influence the quality of the crops, such as harmful organisms – diseases, pests and weed. In order to regulate the occurence of harmful organisms, agricultural measures are taken in the integrated protection system and resistant variants and pesticides are used. The higher the demand on the production quality, the bigger is the volume and the spectrum of pesticides used. The increasing extent of pesticide use also poses a risk for internal production quality and the environment. This fact makes it necessary to monitor unfavourable influences, including the contents of the pesticide residues in barley. This work studies the possibility of multiresidual determination of some selected pesticides in malting barley.
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The concept of control in consolidated financial statements
Kořínek, Miroslav ; Vašek, Libor (advisor) ; Zelenka, Vladimír (referee)
The concept of control is an important determinant of consolidated financial statements. Group of economically related entities and its consolidated financial statements are identified by control concept. Conception of control lies in the model of determination of entities controlled. The evolution of control concept points out, that some entities have not always been integrated in the group or have not been considered controlled. Information value of consolidated financial statements resulting from the control concept is directly influenced by this non-integration represented e.g. by off-balance sheet accounting and Special Purpose Entities. Thesis examines and analyzes present and previous models of control concept of U.S. GAAP, IAS/IFRS and its converged principles.
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European private company
Bártová, Julie ; Grmelová, Nicole (advisor) ; Menzel, Antonín (referee)
The diploma thesis evaluates the possible status of the European private company (SPE),once becomes valid. It describes the legislative procedure and evaluates the impact of the SPE once it exists. At the end, differences between Czech legal form of "Spolecnost s rucenim omezenym" and SPE are discribed.
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