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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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Characterisation of alcoholic beverages by means of spectrospic methods
Fajtl, Zdeněk ; Omelka, Ladislav (referee) ; Polovka, Martin (advisor)
The bachelor’s project is focused on the problem of determination of thermo-oxidative stability of mixed Radler - type drinks with low alcohol content. The project consists of both, theoretical and practical parts. The theoretical part describes the basic technological procedures used in the production of lager-type beer and also mixed drinks of Radler type. It also deals with the issue of antioxidants and/or oxidative processes with specific focus on beer and its components. The author also pays attention to spectroscopic methods, which are recently extensively applied to characterize different qualitative and quantitative parameters of foods; predominantly UV-VIS, IR and EPR spectroscopy. These methods were chosen with respect to the topic being studied. In the experimental part, the application of EPR spectroscopy and spin traps methods for the characterization of thermo-oxidative stability of the selected group of commercially available samples of Radler-type beer is presented. The values of the induction periods which were taken as a measure of thermo-oxidative stability, are compared, both for the group of Radler-type beers under study and for the commercially available samples of typical lager-type beers of identical producers, which were taken as for reference.
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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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In-situ analysis of photosynthetic pigments in bacterial cells
Janošec, Juraj ; Vodička, Juraj (referee) ; Slaninová, Eva (advisor)
This bachelor's thesis deals with the design and characterization of an appropriate combination of methods for the analysis of photosynthetic pigments in a model organism that produces such pigments. Specifically, the microorganism Rhodospirillum rubrum was investigated, which, in addition to photosynthetic pigments, also produces significant products such as potential plastic substitutes called polyhydroxyalkanoates. Structural and quantitative composition of the pigments was analyzed under different cultivation conditions with respect to light conditions. The methods used included spectroscopic techniques, particularly UV-VIS spectroscopy. Specifically, single-beam and double-beam UV-VIS spectroscopy in transmission and diffuse transmission modes, as well as fluorescence spectroscopy, were employed. These methods confirmed the presence of bacteriochlorophyll and several carotenoids, with the highest representation being of spirilloxanthin.
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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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Noninvasive spot analysis of miniatures with portable and laboratory instruments: a methodology for specific use in miniature painting research
Kočí, Eva ; Bezdička, Petr ; Hradil, David ; Garrappa, Silvia ; Hradilová, J. ; Pech, M.
The methodology brings a comprehensive procedure of non-invasive materials analysis of painted miniature artworks, while it is divided into two subsequent parts. In the first part, it describes the use of portable devices for spectroscopic analysis of miniatures, and in the second, it deals with the application of a new methodological procedure for phase/structural materials analysis based on X-ray powder diffraction. The methodology thus includes the following procedures: (i) determination of the elemental composition of the colour layer by the x-ray fluorescence analysis, (ii) identification of binders and other organic compounds using infrared spectroscopy (FT-IR), and finally (iii) phase/mineralogical and structural analysis to describe in more detail the pigments used and processes of their degradation. As part of this last step, the limits of Raman spectroscopy (RS) and the advantages of powder X-ray diffraction and micro-diffraction (XRPD and micro-XRPD) are described, which include greater gentleness to the analysed objects. A very complete and above all non-invasive methodological procedure for the analysis of miniatures is thus offered, which uses the complementarity of individual methods and which can be partly applied already in situ (directly in collection institutions) and partly at specialized workplaces.
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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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