|
|
Metals Transport in the System Soil/Plant. Comparison of the Active and Passive Sampling Method (The Diffusive Gradients in Thin Films Technique)
Trávníčková, Jana ; Janoš, Pavel (referee) ; Chýlková, Jaromíra (referee) ; Čelechovská, Olga (referee) ; Dočekalová, Hana (advisor)
The doctoral thesis deals with comparison between copper uptake by radish (Raphanus sativus L.) and concentration of copper measured by a DGT-device and concentration of copper obtained by extraction with generally used extraction agents (HNO3, NaNO3 and water). Plants were cultivated in pot experiments on a tested non-treated and gradually spiked soil. The amount of copper was determined in various part of radish (whole plant, above- and below-ground part) after mineralization in the APION mineralizer by ET – AAS. The highest concentration was in belowground part, especially in root tissues and sheel of root bulb. It confirms copper is associated with cell walls. The amount of copper taken by radish up does not pass beyond sanitary standards not even in spiked soils and consummation of radish is not unhealthy. Good correlations were found between copper concentration in radish and the amount of copper extracted with HNO3, NaNO3 and water and the amount found in soil solution. Results of extraction with HNO3 confirmed the amount of copper was stable in spiked soils during the pot experiments. The DGT experiments have shown that the rate of resupply from the solid phase to soil solution is constant during the deployment time. Whereas the release of copper decreases after 24 hours in natural soil. Copper added to soil in form of cupric ions is present in the different form after one month-equilibration than copper present in unspiked soils. The results obtained by DGT measurements were approximately up to two orders of magnitude lower than copper concentration obtained by leaching with sodium nitrate. The extraction with sodium nitrate does not provide true reflection of metal availability to plant root system and soil microorganism. High values of correlation coefficients (R2 > 0,9) were found between concentration of copper in radish plant and the concentration of copper in soil solution measured by DGT technique. Concentration of copper in soil solution was three times higher than concentration measured by DGT technique. Soil solution contains species of copper that are not measured by DGT technique and available to plants. Concentration of metals obtained by DGT measurements is more closely to real concentration of bioavailable forms of metal in soil. Therefore it is possible to recommend the DGT technique as a technique for determination of bioavailable forms of copper in soils.
|
|
|
Recycling of phosphorus from waste water
Szotkowski, Matěj ; Bojanovský, Jiří (referee) ; Brummer, Vladimír (advisor)
The focus of this thesis is to create an overview of methods that are used to recycle phosphorus from waste products, primarily from wastewater. The first section of the thesis is dedicated to problems stemming from the limitations of phosphorus resources, their usage and legislative background of phosphorus recycling. Next the physicochemical and biological methods of phosphorus recycling from wastewater and products of its further processing in WWTP are addressed. This part of the thesis contains description of phosphorus recycling methods, their final products and implemented technologies. Brief review regarding the recycling of phosphorus from other waste products including the description of implemented methods follows. In the subsequent part the economic analysis of a chosen phosphorus recycling method (PASCH) is conducted. In the analysis the legislation, processing plant and individual expenditures connected with the method are described. Findings obtained and gathered during the process of the thesis creation are discussed and summarized in the conclusion.
|
|
|
Bioavailability of metals species in water ecosystem
Tandler, Ágnes ; Řezáčová, Veronika (referee) ; Vávrová, Milada (advisor)
Koncentrace volných kovových iontů je často jen malou částí celkové koncentrace kovu v prostředí. Přes tento malý obsah, je ve většině případů koncentrace volných kovových iontů klíčovým faktorem při určování biodostupnosti a toxicity pro organizmus. Membránová technika Donnan se používá k měření koncentrace volných kovových iontů a v této diplomové práci je ověřena pro směsi kovů (Pb + Cu) při absenci a přítomnosti malých organických ligandů. Olovo a měď jsou environmentálně důležité kovy díky své toxicitě a rozdílným vazebným vlastnostem ve vztahu ke studovaným ligandům.
|
|
|
Development of Gel Techniques for in situ Measurement of Bioavailable Metals in Soils and Sediments
Kovaříková, Vladěna ; Sommer, Lumír (referee) ; Janoš, Pavel (referee) ; Dočekalová, Hana (advisor)
The doctoral thesis deals with usage of gel techniques for in situ measurement of bioavailable metals in soils and sediments. The DGT technique was applied to soil samples from the localities of Zlín, Tuřany and Chrlice for estimation of bioavailable metals in soils. These soils were amended by sewage sludges in years 1980-1987. The experiment using diffusive gels with different pore size, APA and RG gels, has shown that the DGT can be used for assessment of trace metal soil complexes - small inorganic and larger organic. The results obtained by DGT measurements were approximately up to two orders of magnitude lower than metal concentrations obtained by leaching with sodium nitrate. The leaching with sodium nitrate does not provide true reflection of metal availability to plant root system and soil microorganisms and the DGT technique seems to be a better predictor of metal bioavailability. Only small differences between undisturbed and homogenized soil samples were found out by application of DGT to soil samples from localities of Veverská Bítýška and Ostrovačice. The undisturbed soil is not homogenous and the DGT unit gives information only about the part of the soil which is in direct contact with the unit. The procedure with soil slurry can be recommended for the characterization of large soil areas and estimation of bioavailable metals in soils. Gel techniques were also used for the study of processes occuring in sediments. Mercury species and other metals were analysed in surface water, pore water and sediments collected from two sampling sites in the Dele River in northern France. This river had been polluted during the last century by the activity of Métaleurop factory, which dealt with metal ore treatment. The application of DGT technique using two specific ion-exchange resins, Chelex-100 and Duolite GT-73, provided assessment of mercury in sediment pore water. DGT and DET techniques together with centrifugation provided also high resolution depth profiles of Fe, Mn, Zn, Pb, Cr and Cd in pore water. It is not possible to determine which sampling site was more contaminated. Only small differences in mercury species and metal content were observed between sampling sites. The Dele River can be classified as contaminated river according to total mercury content in sediments and as slightly contaminated river from the point of view of methylmercury content. Correlations between mercury species and sulphide content confirm that total mercury and sulphide content count among factors influencing the mercury release to pore water and controlling processes of methylation and demethylation. Only low toxicity of sediment slurries was found out by the bioluminiscence test with Vibrio fischeri. The results of doctoral thesis demonstrate gel techniques as a very good tool in environmental analysis.
|
|
|
Bioavailability of magnesium and zinc from food supplements
Lindovský, Patrik ; Křikala, Jakub (referee) ; Diviš, Pavel (advisor)
This bachelor's thesis deals with the analysis of dietary supplements containing magnesium and zinc. The analysis examined the content of active substance and solubility in simulated gastric acid. The method used to analyze the active substance content was inductively coupled plasma optical emission spectrometry. This method was also used to determine the degree of solubility of the active substances. A total of thirteen different samples of dietary supplements were examined, all of which contained magnesium as the active ingredient and four of these samples additionally contained zinc. All samples contained the declared amount of magnesium. The zinc amount in food supplements was in accordance with the content stated on the label. In some samples the amount of zinc was determined to be lower, but the deviation from the declared amount did not exceed 14 %. Solubility tests have shown that some products do not contain a suitable type of coating to protect the active substance, which may cause a deterioration in bioavailability.
|
|
|
Cycling of selected metals in the environment.
Šebková, Michaela ; Diviš, Pavel (referee) ; Dočekalová, Hana (advisor)
This bachelor thesis deals with a group of selected metals (nickel, zinc, copper, cadmium and lead) in environmental components. It occupies with natural and anthropogenic inputs of metals to the atmosphere, the water und the soil and with their transport among them components. It engages too in a question of a penetration of metals to the biosphere and in their ensuant transport within the biosphere. At each metal is description of its natural sources, chemical and physical properties, inputs in environment, transport within the biosphere and positive and negative effects on living organism is described for each studied metal. The last chapter of this thesis deals with determination of selected metals in environmental components. It discribes procedures of determination from planning over sampling and processing of sample to the final determination of metals by instrumental methods.
|
|
|
Biodostupnost vitamínu C z různých zdrojů
Gabrhelová, Lucie
Vitamin C is classified as a hydrophilic vitamin and performs several functions in the human body. It is necessary to obtain it from food, because people have lost the ability to create it due to evolution. Fruits and vegetables are the most important food sources. It is a relatively unstable vitamin and its losses can occur during food processing. Therefore, there are gentler methods of adjustment by which it is possible to limit the given losses. In order to increase stability and thus bioavailability, other methods are also used, most often different types of encapsulation. In addition to food, vitamin C can also be obtained from dietary supplements. These are available on the market in several forms, which differ not only in price or appearance, but above all in the bioavailability of vitamin C itself. The most effective form is liposomal vitamin C, which is in this form able to ensure high bioavailability of vitamin C.
|
|
|
The use of milling and co-milling procedures for preparation of interactive mixtures
Jezerská, Jana ; Šklubalová, Zdeňka (advisor) ; Kvítek, Libor (referee) ; Vitková, Zuzana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Candidate: Mgr. Jana Jezerská Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Ing. Jakub Koktan, Ph.D. Title of Doctoral Thesis: Utilization of technological procedures of milling and co-milling in the preparation of interactive mixtures The dissertation thesis is an annotated summary of the publication and research activities of the author, Mgr. Jana Jezerská (maiden name Brokešová). The thesis is focused on the preparation of binary interactive powder mixtures which consist of the micronized drug particles adhered onto the larger particles of an excipient (a carrier). The binary powder mixtures were prepared by mixing and/or co-milling and characterized by granulometric methods; crystallinity (thermal analysis, X-ray powder diffractometry), the flow properties (shear cell, avalanche properties) and the surface energy were evaluated as well. The dissolution rate of model drugs was estimated using a flow-through powder dissolution cell (USP-4). The used statistical model (central composite design) enabled to establish optimal milling conditions in a ball mill (the milling speed, the milling time, the size of milling balls) for five powder carriers. Based on quadratic response surface,...
|
|
|
Physiological and pathological factors affecting absorption of drugs
Ryšánek, Pavel ; Šíma, Martin (advisor) ; Mičuda, Stanislav (referee) ; Dražanová, Eva (referee)
Absorption of drugs from the gastrointestinal tract after oral administration is a key pharmacokinetic process co-determining the subsequent pharmacodynamic response of the organism and therapeutic efficacy. This dissertation thesis is devoted to the study of factors that influence this parameter. Special emphasis is placed on the study of lymphatic absorption, i.e. the rate of absorption of the active substance via the intestinal lymphatic system. A number of in vivo studies have been carried out in laboratory rats. Pharmacokinetic studies have been performed by means of regular blood sampling from vascular catheters after oral administration of the drug. Lymphatic absorption was investigated in an anaesthetized mesenteric lymphatic duct cannulated rat model. Modern drugs were tested that were incorporated into innovative dosage forms by collaborating chemical and technological institutions. Abiraterone acetate, a lipophilic agent used in the therapy of prostate cancer, was well absorbed from the gastrointestinal tract after administration in the form of oil marbles. This technology also succeeded in reducing the otherwise very significant positive food-effect. Abiraterone acetate was not absorbed to any significant extent via the intestinal lymphatic system. In contrast, lymphatic absorption of...
|
|
|
The use of milling and co-milling procedures for preparation of interactive mixtures
Jezerská, Jana ; Šklubalová, Zdeňka (advisor) ; Kvítek, Libor (referee) ; Vitková, Zuzana (referee)
Charles University, Faculty of Pharmacy in Hradec Králové Department of: Pharmaceutical Technology Candidate: Mgr. Jana Jezerská Supervisor: doc. PharmDr. Zdeňka Šklubalová, Ph.D. Consultant: Ing. Jakub Koktan, Ph.D. Title of Doctoral Thesis: Utilization of technological procedures of milling and co-milling in the preparation of interactive mixtures The dissertation thesis is an annotated summary of the publication and research activities of the author, Mgr. Jana Jezerská (maiden name Brokešová). The thesis is focused on the preparation of binary interactive powder mixtures which consist of the micronized drug particles adhered onto the larger particles of an excipient (a carrier). The binary powder mixtures were prepared by mixing and/or co-milling and characterized by granulometric methods; crystallinity (thermal analysis, X-ray powder diffractometry), the flow properties (shear cell, avalanche properties) and the surface energy were evaluated as well. The dissolution rate of model drugs was estimated using a flow-through powder dissolution cell (USP-4). The used statistical model (central composite design) enabled to establish optimal milling conditions in a ball mill (the milling speed, the milling time, the size of milling balls) for five powder carriers. Based on quadratic response surface,...
|
guest ::
