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Elemental analysis of leaf and soil samples using the ICP-MS
Švecová, Pavla ; Hraníček, Jakub (advisor) ; Kozlík, Petr (referee)
EN Theaimofthisthesiswastodeterminethecontentofselectedelements,namelyarsenic,cadmium, copper, nickel, lead, calcium, and zinc in leaf and soil samples. The analysed samples were received from many locations in the Czech Republic and various European countries. Leaf samples were dried and digested in a microwave digestion system for the determination of thetotal content ofelements.Soil samples wereanalysed usinganextractionprocedurewithaquaregiaas the extractant according to ISO 11466. This method was also applied to certified reference materials to verify the usage of this procedure. The content of elements in leaf and soil samples was analysed by inductively coupled plasma mass spectrometry (ICP-MS). Thecontentofelementsinleavesshowedawiderangeofvaluesforeachelement.Concentrations of elements ranged for calcium 0.98 to 16.6mg g-1 , nickel 0.16 to 10.20μg g-1 , copper 2.60 to 43.80 μg g- 1 , zinc 13.4 to 489 μg g-1 , arsenic 0.01 to 11.60 μg g-1 , cadmium < LOD to 7.02 μg g-1 , and lead 0.03 to 71.40μg g-1 , respectively. Generally, higher values of heavy metals were obtained for samples from areas with mining activities or from industrial zones. Recoveryofelementsintheusedcertifiedreferencematerialsshowedvaluesrangingfrom68.4% to 121%. Two types of reference materials were used, and the recovery...
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Design of the timber trailer
Jílek, Jan ; Pokorný, Přemysl (referee) ; Mergl, Václav (advisor)
The bachelor thesis deals with the design of the structure of a forwarding trailer and analytical stress calculations at specific joints. The first part of the thesis focuses on describing the components, researching similar trailer structures, and summarizing legislative requirements. Furthermore, the structure of the designed trailer is described, and analytical calculations are performed. The thesis also includes drawing documentation of the assembly and subassembly of the welded frame.
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Interaction of yeast and microalgae extracts with cell cultures
Serikbay, Adilkhan ; Holub, Jiří (referee) ; Márová, Ivana (advisor)
The objective of this bachelor thesis was to optimize the extracting of bioactive compounds from microorganisms for the purpose of characterizing and evaluating their cytotoxicity on human cell line HaCaT. During the characterization phase, extract samples were analyzed using spectrophotometric techniques. After exposing the cell line to selected extracts, a cytotoxicity test was performed to assess cell viability using MTT analysis. The theoretical part encompassed an extensive literature review focused on cultivation techniques, human cell lines, cytotoxicity analysis, and viability assessments. The practical section provided a detailed exploration of contemporary extraction techniques utilizing a wide range of both polar and non-polar solvents to enhance the efficiency of extracting active compounds from the yeast strain Rhodotorula toruloides and microalgae Chlorella vulgaris. Active compounds such as ubiquinone, ergosterol, lycopene, and torularhodin were identified in the yeast, while the microalgae were found to contain lutein, chlorophylls, as confirmed by HPLC analysis. The biocompatibility of the optimized extracts from selected strains was verified using the MTT assay on HaCaT cell lines. The aqueous extract from microalgae Chlorella vulgaris exhibited lower toxicity to HaCat cell line, with viability rates exceeding 85%. Yeast extracts from Rhodotorula toruloides initially showed higher viability rates, which, however, decreased with increasing extract concentrations.
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Isolation of active substances with antioxidative properties from lignocellulosic waste
Jurová, Karolína ; Vítová, Eva (referee) ; Kovalčík, Adriána (advisor)
This thesis focuses on isolating active substances with antioxidant properties from lignocellulosic wastes. This work aimed to modify bacterial cellulose (BC) with extracts from grape pomace, which show high antioxidant activity. Grape pomace belongs to the group of lignocellulosic wastes with high content of bioactive compounds such as polyphenols, which contribute significantly to antioxidant efficacy. This work tested the hypothesis that grape extracts can provide antioxidative efficiency to BC. Grape pomace extracts were prepared from grape pomace frozen and lyophilized using a 70% acetone, a 70% ethanol or a 50% ethanol solvent. The highest values of antioxidant activity were determined for the lyophilized extract prepared by extracting grape pomace with 70% acetone. The extracts were further used to modify bacterial cellulose in the form of films (dry BC) and hydrogels (wet BC). It was shown that both forms of BC could be effectively modified using grape pomace extracts, but BC hydrogel achieved higher antioxidant activity compared to BC film. Furthermore, BC with antioxidant activity can be used in various food, cosmetics, and medicine applications.
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Application Data Extraction from Network Protocols
Januš, Filip ; Jeřábek, Kamil (referee) ; Holkovič, Martin (advisor)
This thesis is focused on design and implementation of tool for data extraction from captured network communication. The theoretical part deal with particular network protocols, its behavior, defines keywords and apprises with used tools. Second part is focused on design and implementation of extraction tool, design of declaration language for description of protocols. In the extractor are included third-party tools for analysis particular packets and reconstruction network flows. These tools together with designed declarative language are used due to requirement on easy extendability of designed tool. The end of this thesis is dedicated functional and performance testing of implemented tool.
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Determination of content of organic compounds in biochar
Novotná, Martina ; Řezáčová, Veronika (referee) ; Mravcová, Ludmila (advisor)
Biochar is created during the pyrolysis of organic biomass. Once added into the soil, it can improve its features. Biochars made from sewage sludge have various compositions. It is because of the vast difference between entrance materials. Organic pollutants can be absorbed into its surface during the cooling proces sof pyrolysis. If released into the enviroment, these compounds can cause inhibition of plant growth, get into food chains and adversely affect living organisms. Organic pollutans are determined most often by GC/MS after organic solvent extraction.
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Influence of pH on Extraction of Matter from Biochar-Soil Complex
Jakubčeková, Kristína ; Enev, Vojtěch (referee) ; Kalina, Michal (advisor)
Biochar is one of the possible solutions to improve the soil fertility, therefore it is necessary to investigate both its composition and the impact on the soil under various conditions. The aim of this bachelor thesis is to focus on the description of the influence of pH on the amount and type of substances (molecules, ions) that are leached from the biochar into the soil and thus consequently influence its properties. As a soil model it was chosen cambisol which is the most widespread soil in the Czech Republic. The selected pH values have been defined in such a way to cover the pH range that is common for various soil types in natural conditions. In the experimental part of this thesis the extracts from the used sample of biochar and soil were characterized first. These characteristics obtained in this way were subsequently compared with the data obtained for the biochar-soil complex extracts that was obtained after a defined period of cultivation of the mixture. For the characterization of extracts the basic physico-chemical methods (pH, conductivity, elemental and thermogravimetric analysis, UV-VIS) and also the analysis of leached ions and molecules by means of ICP/OES, GC-MS were used. Evaluated experimental data show that under the condition of cultivation experiments, the influence of biochar was observed only on the basic physico-chemical characteristics of the soil (mainly pH). On the other hand, there was no significant tendency of the impact of biochar on the representation of selected elements and on the content of organic matter in the soil. Long-term biochar-soil cultivation experiments could be a suitable solution.
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Aronia as a raw material for cosmetic production
Palkovská, Kateřina ; Sýkora, Michal (referee) ; Zemanová, Jana (advisor)
This bachelor thesis deals with extraction of polyphenols from fruits and leaves of aronia and consequent use of obtained extract in cosmetic production. In the theoretical part are information about the origin of the aronia, the botanical characteristics of Aronia Melanocarpa and about its utilization. Furthermore, the chemical composition of the plant material of the aronia is described, which is also common for fruits. At the end of the theoretical part are described extraction and separation techniques, methods of determination of total polyphenolic compounds and brief characteristics of the material safety data sheet. The experimental part describes the optimization of the prepared extract so that the extract contains as many polyphenolic compounds as possible. 50% ethanol at room temperature was shown to be optimal for leaf and fruit extraction, and the maceration time was found to have a significant effect on the polyphenolic compounds obtained. For the obtained optimized macerate, some chemical and physical properties such as pH, density, refractive index were determined for the purpose of producing a material safety data sheet and product specification. At the end of the experimental part were prepared cosmetic products with the addition of macerate from crushed aronia fruits.
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Developement and optimization of the method for the extraction of ferulic acid from wheat bran
Hubačová, Klára ; Štursa, Václav (referee) ; Pořízka, Jaromír (advisor)
Bachelor thesis is considering usage of wheat bran for an extraction of ferulic acid. Wheat bran is a large-scale by-product of milling industry which is produced during milling of cereals (wheat) into flour. This low-cost product is usually used as a livestock feed. An initiative is raised for some other potential applications, because too large quantity produced every year can not be consumed just as a feed. There is a significant amount of phenolic acids from which ferulic acid is the most abundant one. It was found out after examination of structure of the wheat bran. This acid is connected with polysaccharides of a cell wall. The alkaline hydrolysis was used to disrupt a linkage between ferulic acid and polysaccharides. Then ethanol was added to precipitate the polysaccharides and the mixture was filtered. The filtrate contains ferulic acid which has great health benefits such as anti-inflammatory, antioxidant, anti-carcinogenic, antimicrobial effect etc. It plays an important role as an agent against UV radiation in the cosmetic products.
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Separation of lipids from cell tissues
Kotland, Vojtěch ; Lacina,, Lubor (referee) ; Svěrák, Tomáš (advisor)
This master’s thesis is focused on lipid separation from tissue cells. Thesis is divided into theoretical and experimental part. In the theoretical part is summarized current knowledge about lipids, their properties and methods used to separate them from tissue cells. Those methods were compared and one of them was chosen to be used in the experimental part. Theoretical part is ended with reviews aimed towards the research in this area of chemistry. Experimental part describes factors affecting chosen method of lipid separation from tissue cells. The measurements were chosen so that they could be easily reproduced. Values for each factor were experimentally determined to increase the amount of fat separated. All factors were compared and based on their summarization the optimization for whole method was produced.
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