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Development and optimization of ointment preparation for burn healing
Müllerová, Kristýna ; Sedláček, Petr (referee) ; Enev, Vojtěch (advisor)
This bachelor's thesis aims to prepare ointments based on an ointment base with the addition of a bioactive component of chlorophyll according to a recipe from an unknow doctor. The basic characteristic of emulsions was performer in the theoretical part, their instability and possible methods of stabilization were described. Furthermore, the reader is acquainted with the bioactive substance of chlorophyll, selected ointments for the healing of burns and wounds and finally with the use in medicine. In the Experimental part, the preparation of emulsion bases of ointment was described. Based on a performed analysis of stability using analytical centrifuge, two ointments bases were selected, to which other components were added – chlorophyll, beeswax, and chamomile extract. The stability of completely prepared ointments was studied at 25 °C and 37 °C, this analysis was performed even after a longer time interval. Using ATR-FTIR spectrometry the present functional groups were identified at prepared ointments, individual components of the ointments base and chlorophyll. Based on the stability measurement of the prepared ointments and rheological measurements (oscillation and rotational measurements), it was evaluated that the best properties were shown by the prepared ointment with an ointment base consisting of 30 wt. % white vaseline and 70 wt. % synderman.
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Carbon nanoparticles from lignite
Kohoutková, Eliška ; Enev, Vojtěch (referee) ; Pekař, Miloslav (advisor)
These bachelor thesis focuses on lignite as a potential raw material for the carbon quantum dots extraction. There was proposed mechanochemical process of isolation these nanoparticles from lignite based on literature search. Lignite was mechanically stressed and subsequently oxidized to hydrogen peroxide. The results show that proposed method will have to be modified but lignite could be used as a feedstock for the carbon quantum dots extraction.
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Optimization of the Methodology for Assessment of Biochar Effect on the Growth of Model Plants
Štorková, Natálie ; Enev, Vojtěch (referee) ; Kalina, Michal (advisor)
This bachelor thesis is studying the effect of biochar on the growth of model plant and deals with the optimalization of the methods for assessing its impact. Theoretical part describes the properties and utilization of soil conditioners, special attention is focused on biochar. According to the literature research, maize (Zea mays) was chosen as a model plant for cultivation experiment and subsequently the application doses of biochar were also defined. The cultivation experiment took place in growing box under controlled illumination and irrigation. Plant dry weight weighing after cultivation, continuous measurement of plant height during the cultivation and also image analysis of the root system were used for evaluating the influence of biochar on quantitative and qualitative properties of model plants. From obtained data it can be summarized that the growth differences were influenced by the application dose, the type of biochar and also by type of soil, which was used for the cultivation experiment.
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Molecular organization of humic acids in solutions
Chytilová, Aneta ; Enev, Vojtěch (referee) ; Klučáková, Martina (advisor)
The diverse structure and content of the highly varied functional groups of humic acids determine these substances as a worthwhile study material for a number of scientific institutions. Above all, the structure causes a wide range of their interesting properties, especially spectral, colloidal, electrochemical, ion-exchange and adsorption properties. Humic acids have variety of utilization in the industry while they have been the subject of a range of further research and development. The character of these complex heterogeneous polydisperse substances is mainly cyclic and aromatic, which according to some studies results in their brown color. Generally, there are multiple theories assuming their potential secondary structure. The aim of this study is the analysis of structure and conformation of humic acids in aqueous solutions. For the purposes mentioned above a concentration series of humic acids have been prepared in four different mediums: 0,1 M NaOH, humic acids in water with pH modified to 12 (basic medium), 0,1 M NaOH + 0,1 M HCl, 0,1 M NaCl (neutral medium). In order to study conformations several analytic methods have been used: ultraviolet and visible spectroscopy, dynamic light scattering, electrophoretic light scattering, potentiometric determination of pH and direct conductimetry. Throughout the experimentation the emphasis was mainly on the purity of humic acids extracted from lignite.
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Application of thin layer chromatography (TLC) for fractionation of humic substances.
Hegrová, Nela ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The main aim of this Bachelor thesis was to suggest and optimize a method of fractionation of organic matter of humic substances using thin-layer chromatography (TLC). HS Pahokee Peat standards have been characterized by thermochemical and spectrometric techniques such as thermogravimetry, elemental analysis, UV-Vis and Fourier-transform infrared spectrometry. Molecular absorption spectrometry in the ultraviolet and visible range of electromagnetic radiation and steady-state fluorescence spectrometry were used for physicochemical characterization of organic fractions. Using fluorescence spectrometry, humic substances were found to be composed of fluorophores of humic and non-humic (protein) character. Organic fractions corresponding to the humic fluorphores were characterized by a higher aromaticity, average molecular weight and higher content of oxygen substituents on the aromatic nucleus. In contrast, the organic fractions corresponding to the protein constitutional units were distinguished by low values of the humification index. These tell us about microbial origin of these organic substances during the genesis of HS Pahokee Peat.
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Complex physicochemical analysis of natural medicinal water
Machátová, Nikol ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
This bachelor thesis is focused on the study of the content humic substances in natural medicinal water. Humic substances extracted from this water were characterized by UV-VIS and FTIR spectroscopy, hereafter microbiological tests were performed. The main aim was determine the content HS using the norm ČSN 75 7536 and the calibration curves of standard fulvic acid Suwannee River. Another part of this bachelor thesis was focused on spectrometric characterization HS after different degree of purification. Humic substances were characterized by absorption coefficients and FTIR spectroscopy.
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Interactions of pharmaceuticals with humic acids
Libiger, Jan ; Enev, Vojtěch (referee) ; Klučáková, Martina (advisor)
The bachelor thesis is focused on interaction of drugs with humic substances, which are part of organic soil matter. The results would help in understanding the behavior of drugs in soil and other natural systems. Three drugs were selected. Humic acid was selected as a sorbent, which was extracted from lignin, the lower one is assumed to be the same as that in organic soil. Based on a comparison of the measurement results using the UV-VIS method, it was determined how much the acid of the given drug is able to absorb and how much it is released back into the water. The theoretical part deals with the information about soil organic matter, with the information about humic substances, with the information about drugs such as ibuprofen, sulfamethoxazol or sulfapyridine. Furthermore, the theoretical part deals with methods of analysis.
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Utilization of vibrational spectroscopy in study on interactions between humic substances and organic ions.
Stehlíková, Kristína ; Enev, Vojtěch (referee) ; Sedláček, Petr (advisor)
The main objective of this bachelor thesis was to validate the potential of the utilization of vibrational spectroscopy in the study on interactions between humic substances and organic ions. Unmodified (HA) and methylated humic acids (mHA) were chosen as model humic substances and organic ions were represented by methylene blue, rhodamine 6G and Septonex. Firstly, a suitable infrared spectroscopy technique was chosen. The results of optimization measurements showed that spectra with the best resolution can be obtained using the DRIFTS technique. The next part of the thesis discusses the effect of methylation in the structure of humic acids. Significant differences were recorded in mHA compared to the unmodified humic acids. Finally, the spectra of humic acid – organic ion complexes were compared to the spectra of prepared blank samples. It was noted that the spectra of complexes are not only a simple sum of the pure individual substances’ spectra, but also shifts and changes in the intensity of different absorption bands were recorded there. It suggests that non-covalent interactions played an important role in the complexes. Infrared spectroscopy was proved to be a useful method for investigating these interactions.
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Raman spectroscopy as a tool for analysis of biotechnologically relevant microorganisms
Záhorská, Linda ; Enev, Vojtěch (referee) ; Mgr.Ota Samek, Ph.D. (advisor)
The diploma thesis deals with the study of biotechnologically significant microorganisms, using the Raman spectroscopy. Content of the theoretical part is brief characteristic of Raman spectroscopy as a method, its use in practice and also use as a tool for monitoring of biotechnologically processes. Thesis was further focus on the biotechnologically significant microorganism Aureobasidium pullulans, its use in biotechnology and also for over-produced substances and in particular poly-L-maleic acid and pullulan. The content of the experimental part was study of selected strains A. pullulans, specifically stains as DSMZ, CCM F148 and CCM 8182, using Raman spectroscopy on the various types of culture media. Subject of practical part research was too production of extracellular polymers, acid poly-L-apple and pullulan, by selected strains A. pullulans. Objective of my thesis was described and determinate, spectra of individual strains as well as extracellular products, mainly pullulan, and then choose suitable production medium and optimal production strain A. pullulans. During experimental work was found, that optimal production strain was DSMZ strain culture on the mineral medium with the addition of yeast autolysate, which was optimal medium type. The content of the pullulan produced was for gravimetric determination, 6,3g/L, which also confirmed the results of the HPLC method. It was experimentally found, that Raman spectroscopy isn´t suitable method for quantification of extracellular products, but is appropriate and was used for PCA analysis of individual strains.
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Transport of pharmaceuticals in soil systems
Janebová, Denisa ; Enev, Vojtěch (referee) ; Klučáková, Martina (advisor)
Drugs have a negative effect on nature. If they do not degrade in wastewater treatment plants, they can contaminate lakes, rivers and even drinking water. However, the soil contains soil organic matter, which has chelating properties and can prevent the migration of the drug. The aim of this bachelor thesis was to map the transport of the selected drug in the soil column and try to determine its diffusivity. Sulfapyridine was chosen for transport. Sulfapyridine belongs to a group of sulfonamide antibiotics that are often detected in the environment. It is mainly used in veterinary medicine to treat various infections. The partial goal was to describe the basic properties of the soil depending on the depth of the soil layer. The drug concentration profile in the soil column was determined by UVVIS spectrometry in soil extracts. The following reagents were used for leaching: distilled water, as a pure solvent without the presence of other substances, tap water as a model reagent replacing the soil solution and magnesium chloride solution, which is used for soil extracts of freely moving and ionically bound substances in the soil.
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