|
| |
|
|
Effect of triazole fungicides on soil properties
Račko, Ján ; Ryšlavá, Helena (advisor) ; Smrček, Stanislav (referee)
Plant protection still depends on the use of pesticides, often in mixtures that pose a potential threat to non-target organisms. Triazole fungicides (tebuconazole, penconazole and others) are widely used in agriculture against fungal pathogens, but they can affect both the metabolism of the plants themselves and the composition of soil organisms. Biochemical indicators of soil health and quality include the content of microorganisms and the activity of glycosidase, protease and dehydrogenase enzymes. In this work, it was investigated how the application of penconazole and tebuconazole and their combination by watering the soil and spraying on the leaves of edible tomato plants (Solanum lycopersicum L., cv. Cherrola) affects the activities of enzymes involved in carbon and phosphorus metabolism. Endoglycosidases involved in the degradation of plant and fungal cell walls (cellulases, chitinases) were found to have reduced activities in the soil contaminated with triazoles, while the activity of endo-β-1,3-glycanase was increased in the sPT group. The activity of exoglycosidases (β-glucosidases, β-hexosaminidases, β-galactosidases and α-mannosidases) in the soil was increased. The activity of these enzymes was also determined in the roots of tomato plants, from which enzymes can be secreted into the soil....
|
|
|
Phytoextraction of mixed drug samples from aqueous solutions
Hájková, Eliška ; Smrček, Stanislav (advisor) ; Soudek, Petr (referee)
A number of contaminants have been detected in the environment, including pharmaceuticals. Their presence in soil, water sources can have a toxic effect on organisms due to their constantly increasing concentration. The method of phytoremediation uses the ability of plants to absorb these contaminants and detoxify them by various mechanisms. The aim of this work was the phytoextraction of ibuprofen using maize (Zea mays) from aqueous solutions. Phytoextraction of ibuprofen after cultivation with added dextromethorphan was also carried out. The quantitative amount of extracted ibuprofen was detected by HPLC with UV detection. Ibuprofen has been very well extracted by plants. In the presence of dextromethorphan, the efficiency of phytoextraction was decreased. The phytoextraction efficiency of ibuprofen was 0.10 mg per gram of leaf fresh weight, while in the presence of dextromethorphan, the phytoextraction efficiency was 0.09 mg per gram of leaf fresh weight. After phytoextraction of ibuprofen, the antioxidant capacity was determined by FRAP method of leaf and root extracts of the plants, of which the highest values were observed in the roots of plant grown with ibuprofen in combination with dextromethorphan. The phenolic compounds were also detected in leaves and roots, where the highest percentage...
|
|
| |
|
|
Synthesis of multiply negatively charged anchors with sulfonate groups
Tomanová, Adéla ; Jindřich, Jindřich (advisor) ; Smrček, Stanislav (referee)
The scope of the bachelor thesis is the synthesis of derivatives derived from the neopentyl skeleton, containing one detection or reactive group and one, two or three sulfonate groups. These compounds have applications for the preparation of molecules capable of electrostatic self-assembly, useful, for example, for modifying positively charged surfaces of stationary phases (e.g. aminopropyl silicagel) in chromatography. Keywords: modification of charged surfaces, sulfonate groups, neopentyl derivatives
|
|
| |
|
| |
|
| |
|
|
Preparation of organocatalysts derived from thiourea containing saccharide units
Řehůřková, Tereza ; Veselý, Jan (advisor) ; Smrček, Stanislav (referee)
4 ABSTRACT This diploma thesis is focused on the synthesis of new bifunctional thiourea organic catalysts containing a carbohydrate moiety, in particular D-glucose with modification on the primary hydroxyl group. The first part of this diploma thesis describes a modification of synthesis of the known bifunctional thiourea catalyst with 2,3,4,6-tetra-O-acetyl-β-D-glucopyranose and (1R,2R)-diaminocyclohexane. The second part is dedicated to the synthesis of new bifunctional thiourea catalysts with modification of the carbohydrate moiety. We focused on per-O-acetyl-β-D-glucopyranose derivatives with pefluoroalkyl moiety on the primary hydroxyl group. We examined different ways of the preparation of 6-O-perfluoroalkylated glucose derivatives. These perfluoroalkylated carbohydrate compounds were transformed into corresponding glycosyl isothiocyanates. Those derivatives upon treatment of (1R,2R)-diaminocyklohexane or 3,5- bis(trifluormethyl)aniline afforded new bifunctional thiourea organocatalysts.
|
|
|
Analysis of anthraquinone secondary metabolites produced by Geosmithia spp.
Křesinová, Zdena ; Smrček, Stanislav (referee)
Analysis of anthraquinone secondary metabolites produced by Geosmithia spp. Zdena Křesinová Geosmithia species are little known fungal symbionts of bark beetles. Secondary metabolites from lilac colored species G. lavendula (strain MK 1008) and nine other Geosmithia species were investigated in order to elucidate their structures and quantify their production during submerged cultivation. Five hydroxylated anthraquinones (HAs) were isolated from culture media during submerged cultivation of the fungi and three of them were identified using NMR and MS techniques as 1,3,6,8- tetrahydroxyanthraquinone (1), rhodolamprometrin (1-acetyl-2,4,5,7- tetrahydroxyanthraquinone; 2), and 1-acetyl-2,4,5,7,8-pentahydroxyanthraquinone (3). Preparation, quantification and identification of HAs in fungal samples involved a SPE step, semi-preparative HPLC/UV and UPLC/UV methods. For optimization of analytical methods, separation qualities of two types of reversed phase sub-2-micron particle sized columns and one 5-micron particle sized column were tested. The most efficient Sheild RP C18 column filled with 1.7 µm particles was then used for quantification of HAs production during the cultivation period. Calibration curves for metabolites 2 and 3 (representing the majority of produced metabolites) were determined in...
|
guest ::
