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Influence of compost application on properties of soil humic substances
Enev, Vojtěch ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The aim of this diploma thesis is to study to the influence of compost addition to soil humic substances extracted from blackland luvicsol. Humic substances extracted from soil and from compost were characterized by titration with potentiometrical and conductival indication, UV-VIS, FT-IR and 3D EEM fluorescential spectroscopy. Compost in amount of 124, 239 and 478 t/ha was applicated and manured into dept of 150 mm at blackland luvicsol. The main aim of thesis was the appraisal of compost influence into fluorescent attributes of soil HS and localization of fluorescent peaks at excitation emission spectrums. Next part of diploma thesis was focused on the study of spectroscopic attributes of soil HS and compost by UV-VIS and infrared spectroscopy with Fourier transformation. Humic substances were characterized by humifical index E4/E6 and transmissional vibratile spectrums. The last aim of diploma thesis were the characterization of soil HS extracts and compost by acidimetral titration. For each sample was calculated value of H+ ionts amount of substance from measured titrational curves.
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Lanthanidocenes and their Precursors Synthesis
Koporecová, Zuzana ; Pilátová, Ivana (referee) ; Richtera, Lukáš (advisor)
The aim of this work is to summarize the issues spectroscopic techniques useful in organometallic and polymer synthesis, including sample preparation and interpretation of the data, with a focus on NMR spectroscopy, vibrational spectroscopy and X-ray structural analysis. Part of the work deals with the characteristics of lanthanides, lantanidocens and synthesis of some lantanidocene compounds. Next are in this thesis prepared special laboratory techniques, working with Schlenk vessels, glove box and a dry bag.
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Modern Approaches in Qualitative Aspects of Foods Assessment
Tobolková, Blanka ; Omelka, Ladislav (referee) ; Rapta, Peter (referee) ; Buňka, František (referee) ; Polovka, Martin (advisor)
Antioxidant properties and some other characteristics of selected organic and conventional products (wine, spelt flours) were evaluated in view of their potential utilization as markers suitable for food unambiguous differentiation according to the affiliation to production system. Beside these, study of fruit juices stability during storage in dependence on different technological procedures of juice processing was performed. In both cases, combination of dominantly EPR and UV/VIS spectroscopy but also other methods (e.g., HPLC, AAS, electrophoresis) was applied to evaluate the stability and antioxidant properties of selected samples. Statistical methods, especially methods of multivariate statistics were used to assess the influence of production and technological-processing operations on antioxidant status of foods and their selected characteristics. Qualitative analysis of Slovak and foreign organic and conventional wines proved that their antioxidant properties are influenced by production system, vintage and variety. On the basis of statistical analysis, descriptors of AAE, kTEMPOL and %RS were selected as the most powerful markers for Slovak organic and conventional wines discrimination. The discrimination of white and red organic and conventional wines possessed 100% and 95.2% correctness, respectively. High correctness of differentiation of Slovak and foreign wines was also achieved. Monitored descriptors of antioxidant activity of spelt flours varied in dependence on season, origin, variety, production system and depend also on way of spelt treatment, although this effect is not so significant. It was also confirmed that the type of extraction agent substantially affects the composition of extracts including polyphenols and flavonoids concentration, affecting thus also their antioxidant activity. Mixture of 50% ethanol/water was selected as the most promising extraction system. Although the results of individual spectroscopic assays revealed high variability and often ambiguous trends, the differences found were sufficient for successful differentiation of both wines and spelt flour samples according to the selected criteria by multivariate statistical processing of the data. Influence of changes in technological procedures of fruit juice processing (nitrogen atmosphere application, utilization of caps with oxygen scavengers) on radical-scavenging properties of 100% pineapples juices with pieces of pineapple and 100% orange juices with pulp was assessed as well. Results obtained proved that antioxidant activity of juices varied in dependence on storage conditions (temperature, storage time, light exposure) and depends also on origin, variety and quality of fruit used. However, the application of nitrogen atmosphere and active packaging materials is not sufficient enough to eliminate the oxidation reactions in juices, but changes in antioxidant activity are better predictable. It can be concluded that EPR spectroscopy could be effectively applied for wines and spelt flours differentiation according to the way of production and to assess the stability of food products, either alone or in combination of UV/VIS spectroscopy and the other methods, utilizing multivariate statistics for processing of experimental data.
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Study of the binding interaction of tyrosine kinase inhibitors with serum albumin
Rodová, Marie ; Indra, Radek (advisor) ; Heidingsfeld, Olga (referee)
Sunitinib and vandetanib are anti-cancer medications prescribed for medullary thyroid cancer (in the case of vandetanib) and for renal cell carcinoma, gastrointestinal stromal tumor, and pancreatic cancer (in the case of sunitinib). They belong to the group of tyrosine kinase inhibitors and act by exhibiting anti-angiogenic effects and by inhibiting tumor cell proliferation and survival through VEGFR. Additionally, vandetanib also inhibits tumor cell survival via EGFR and RET. In the presented thesis, we investigated the binding interaction between serum albumin and the TKIs vandetanib and sunitinib using BSA, HSA, and blood plasma. We examined the differences in interaction between the TKIs and various serum albumins, including pure BSA, pure HSA, and blood plasma, as well as the nature and location of the binding interaction. Additionally, we studied the influence of other ligands on this interaction and the photosensitivity of sunitinib itself. Utilizing spectroscopic techniques, including UV-VIS absorption and fluorescence quenching, we have determined the Stern-Volmer and binding constants, as well as the thermodynamic parameters, for the binding interactions of sunitinib and vandetanib with BSA and HSA. Our results indicate that complex formation occurs between BSA and sunitinib, BSA and...
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Use of spectroscopic methods in colorectal cancer detection.
Miškovičová, Michaela ; Petruželka, Luboš (advisor) ; Soumarová, Renata (referee) ; Kiss, Igor (referee)
Colorectal cancer is one of the most common cancers and a global health problem. Approximately 8,000 new cases are diagnosed annually in the Czech Republic and about half of them die from this malignancy, with 20 % patients being under 60 years of age. It is still true that the greatest hope for successful treatment and management of the disease is given to patients by early diagnosis of cancer. There is still a remarkably high proportion of detection of colorectal cancer in the advanced stage, which is mainly due to the absence of reliable and sensitive clinical methods. The still unfavorable epidemiological situation is a clear challenge to further strengthen all activities aimed at active prevention and early diagnosis. Colorectal cancer is the best preventable disease of the gastrointestinal tract, it lasts for several years, when an invasive lesion gradually develops through a precursor lesion. This offers a sufficiently long diagnostic window, Therefore, attention is currently being focused to find affordable, sensitive and minimally invasive techniques that can provide early, simple, rapid, inexpensive and reliable diagnosis of this disease and could thus support or replace conventional diagnostic methods in the future. In our work, we focused on the use of completely new diagnostic...
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Polarity-based sequential extraction method for the study of organic matter isolated from biochar
Vojáčková, Beáta ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
This master’s thesis completely charakterizes the organic matter of biochar from a physicochemical point of view. The theoretical part is focused mainly on the use of biochar in technology industry, substance content, extraction and instrumental techniques used for its study. A Soxhlet apparatus and the method of sequential fractionation by a series of six organic solvents, which were ranked based on their increasing polarity, were used to extract the matter. The experimental part discusses the analysis of the obtained samples using thermal methods such as thermogravimetric (TGA) and elemental analysis (EA). In our case optical methods were used also; spectrometry with Fourier transform (FTIR-ATR), ultraviolet-visible (UV-VIS) and fluorescence spectrometry. Thanks to the scanning electron microscopy (SEM) were obtained images of the biochar surface. Continuous characterization including the results of the biogenic element content, individual functional groups and the values of established indices, allowed us to define the organic parts of biochar and contributed to the implementation of better methodology regarding the investigated issue.
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Analytické metody pro stanovení kyseliny jablečné a vinné ve víně
Töröková, Lucie
Malic acid and tartaric acids are the most important organic acids in grape juice and wine. They can be detected in liquid samples by several different analytical methods. The aim of this work was to compare various analytical techniques used for the qualitative and quantitative analysis in grape juice and wine. Individual methods were divided into 5 groups: chromatographic, electrochemical, spectroscopic, enzymatic methods and titration. These methods were described in details and summarized. Some of these methods are already in decline or they are utilized by small winemakers, only. In contrast, the development of instrumentation technique is still ongoing. Detection limits are constantly improved and various machine combinations are tested. The most commonly used methods include chromatography techniques in combination with various types of detectors, its connection with other devices, and even their series connection.
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Modern Approaches in Qualitative Aspects of Foods Assessment
Tobolková, Blanka ; Omelka, Ladislav (referee) ; Rapta, Peter (referee) ; Buňka, František (referee) ; Polovka, Martin (advisor)
Antioxidant properties and some other characteristics of selected organic and conventional products (wine, spelt flours) were evaluated in view of their potential utilization as markers suitable for food unambiguous differentiation according to the affiliation to production system. Beside these, study of fruit juices stability during storage in dependence on different technological procedures of juice processing was performed. In both cases, combination of dominantly EPR and UV/VIS spectroscopy but also other methods (e.g., HPLC, AAS, electrophoresis) was applied to evaluate the stability and antioxidant properties of selected samples. Statistical methods, especially methods of multivariate statistics were used to assess the influence of production and technological-processing operations on antioxidant status of foods and their selected characteristics. Qualitative analysis of Slovak and foreign organic and conventional wines proved that their antioxidant properties are influenced by production system, vintage and variety. On the basis of statistical analysis, descriptors of AAE, kTEMPOL and %RS were selected as the most powerful markers for Slovak organic and conventional wines discrimination. The discrimination of white and red organic and conventional wines possessed 100% and 95.2% correctness, respectively. High correctness of differentiation of Slovak and foreign wines was also achieved. Monitored descriptors of antioxidant activity of spelt flours varied in dependence on season, origin, variety, production system and depend also on way of spelt treatment, although this effect is not so significant. It was also confirmed that the type of extraction agent substantially affects the composition of extracts including polyphenols and flavonoids concentration, affecting thus also their antioxidant activity. Mixture of 50% ethanol/water was selected as the most promising extraction system. Although the results of individual spectroscopic assays revealed high variability and often ambiguous trends, the differences found were sufficient for successful differentiation of both wines and spelt flour samples according to the selected criteria by multivariate statistical processing of the data. Influence of changes in technological procedures of fruit juice processing (nitrogen atmosphere application, utilization of caps with oxygen scavengers) on radical-scavenging properties of 100% pineapples juices with pieces of pineapple and 100% orange juices with pulp was assessed as well. Results obtained proved that antioxidant activity of juices varied in dependence on storage conditions (temperature, storage time, light exposure) and depends also on origin, variety and quality of fruit used. However, the application of nitrogen atmosphere and active packaging materials is not sufficient enough to eliminate the oxidation reactions in juices, but changes in antioxidant activity are better predictable. It can be concluded that EPR spectroscopy could be effectively applied for wines and spelt flours differentiation according to the way of production and to assess the stability of food products, either alone or in combination of UV/VIS spectroscopy and the other methods, utilizing multivariate statistics for processing of experimental data.
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Influence of compost application on properties of soil humic substances
Enev, Vojtěch ; Pospíšilová, Ľubica (referee) ; Klučáková, Martina (advisor)
The aim of this diploma thesis is to study to the influence of compost addition to soil humic substances extracted from blackland luvicsol. Humic substances extracted from soil and from compost were characterized by titration with potentiometrical and conductival indication, UV-VIS, FT-IR and 3D EEM fluorescential spectroscopy. Compost in amount of 124, 239 and 478 t/ha was applicated and manured into dept of 150 mm at blackland luvicsol. The main aim of thesis was the appraisal of compost influence into fluorescent attributes of soil HS and localization of fluorescent peaks at excitation emission spectrums. Next part of diploma thesis was focused on the study of spectroscopic attributes of soil HS and compost by UV-VIS and infrared spectroscopy with Fourier transformation. Humic substances were characterized by humifical index E4/E6 and transmissional vibratile spectrums. The last aim of diploma thesis were the characterization of soil HS extracts and compost by acidimetral titration. For each sample was calculated value of H+ ionts amount of substance from measured titrational curves.
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Lanthanidocenes and their Precursors Synthesis
Koporecová, Zuzana ; Pilátová, Ivana (referee) ; Richtera, Lukáš (advisor)
The aim of this work is to summarize the issues spectroscopic techniques useful in organometallic and polymer synthesis, including sample preparation and interpretation of the data, with a focus on NMR spectroscopy, vibrational spectroscopy and X-ray structural analysis. Part of the work deals with the characteristics of lanthanides, lantanidocens and synthesis of some lantanidocene compounds. Next are in this thesis prepared special laboratory techniques, working with Schlenk vessels, glove box and a dry bag.
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