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Influence of elevated carbon dioxide concentration at Rubisco activity and its content in sunny and shaded leaves of beech
Vičíková, Magda ; Vitoulová, Eva (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis focuses on influence of elevated carbon dioxide concentration at Rubisco activity and its content in sunny and shaded leaves of beech (Fagus sylvatica). The initial and total activities were measured spectrophotometrically, the content of Rubisco was determined by using SDS-PAGE method. It was observed statistically significant higher activity of Rubisco in leaves cultivated under elevated concentrations of carbon dioxide in June but not in September. In contrary, exposure of leaves (sunny/shaded) did not have significant influence on Rubisco activity in June, but in September was found lower activity of Rubisco in shaded leaves than in sunny leaves. The content of Rubisco was lower in leaves cultivated under elevated concentrations of carbon dioxide (acclimation), with the exception of shaded leaves in September. There was found significantly lower Rubisco content in shaded leaves than in sunny leaves both in June and in September.
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Features and functions of glycocalyx of trematode cercariae
Chaloupecká, Jana ; Mikeš, Libor (advisor) ; Kašný, Martin (referee)
Trematodes are parasites from phylum Platyhelminthes which have compex life cycles involving two to four hosts. This work focuses especially on trematodes of the family Schistosomatidae. Their cercariae which leave the snail intermediate host, actively penetrate the skin of definitive hosts and transform into schistosomula. This is accompanied by detachment of cercarial tail and emptying of penetration glands. During transformation, cercarial bodies undergo extensive ultrastructural and molecular changes. One of these changes is the loss of surface glycocalyx which represents a protective coat in the aquatic environment. In glycocalyx shedding, participation of proteolytic enzymes from cercarial penetration glands is expected during invasion of the host. Glycocalyx has specific composition of saccharide molecules which are bound to lipids or proteins on the membrane of cercarial tegument. This work describes the origin, ultrastructure, saccharide composition, function and shedding mechanism of cercarial glycocalyx.
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Abundance of NADP-dependent enzymes in plants
Kovaľová, Terézia ; Hýsková, Veronika (advisor) ; Ryšlavá, Helena (referee)
NADPH is an important molecule in plant metabolism. It is an indispensable substrate for many processes; participates in redox balance of the cell and it is a part of antioxidant defense system in plants. In this work, activities of selected NADP-dependent enzymes producing NADPH, NADP-malic enzyme (oxalacetate decarboxylating) (NADP-ME, EC 1.1.1.40), NADP-isocitrate dehydrogenase (decarboxylating) (NADP-ICDH, EC 1.1.1.42), glukosa-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) and shikimate dehydrogenase (SDH, EC 1.1.1.25) in various plants and their parts (leaves, fruits, seeds) were established and compared. The aim of this work was to select suitable model plants for testing the effect of abiotic stress on NADP-dependent enzymes and also to select the best source for purification of these enzymes. Cucumber (Cucumis sativa L.), pea (Pisum sativum L.), or water-lily (Nymphaea) were chosen as suitable water-receptive model plants and Capsella bursa-pastoris as xerophilic plant from 19 analyzed plants. From group of 39 plants the most suitable for purification of NADP-ME were roots of Chinese radish (Raphanus sativus var. Major), which were simultaneously a rich source of other analyzed NADP-enzymes. The best source of NADP-ICDH was poppy (Papaver somniferum), or quinoa Chenopodium quinoa. For...
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Connection between abiotic stress and NADP-dependent enzymes in plants
Plisková, Veronika ; Hýsková, Veronika (advisor) ; Kubíčková, Božena (referee)
Salt stress in plants is accompanied with decreased growth caused by lowered leaf water potential, closed stomata and thus reduced photosynthesis producing NADPH. However, NADPH is indispensable coenzyme for biosynthetic processes (e.g. biosynthesis of osmotically active compounds decreasing influence of stress) and for antioxidant system. In this study it was examined, whether NADP-dependent enzymes: glucose-6- phosphate dehydrogenase (G6PDH), NADP-isocitrate dehydrogenase (NADP-ICDH), NADP-malic enzyme (NADP-ME) and NADP-shikimate dehydrogenase (SDH), producing NADPH are involved in plant defence response against 100 mM NaCl. Three different model plants were used: Pisum sativa L., Phaseolus vulgaris L. and Cucumis sativa L. While in leaves of pea and bean plants salt stress caused rather decreased activities of particular NADP-dependent enzymes (especially of G6PDH and NADP-ICDH), in leaves of cucumber 9th and 11th day of stress condition were found increased activities of all studied enzymes. Simultaneously the Na+ content in salt-stressed plants was analysed by atomic emission spectrometry.
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Changes in cytokinin contents and metabolism in spinach in response to zinc excess in soil
Žižková, E. ; Gajdošová, Silvia ; Pavlíková, D. ; Pavlík, Milan ; Száková, J. ; Motyka, Václav
Changes in endogenous cytokinin (CK) contents and metabolism in spinach (Spinacia oleracea L.) responding to excessive amounts of zinc in soil were studied. Application of three zinc rates in soil (250, 500, 750 mg.kg-1) resulted in a progressive (1.7- to 3.3-times) increase of endogenous CKs in spinach leaves. This increase was predominantly due to accumulation of inactive and storage CK forms (N- and O-glucosides) and was accompanied with an enhanced activity of cytokinin oxidase/dehydrogenase (CKX), the key CK degradative enzyme, especially on the highest zinc rate (750 mg.kg-1 soil). On this rate, maximum endogenous CK concentrations in both control and stressed plants were found at the first and the last samplings, i.e. in the course of very young leaf development and just before or during flowering. The CKX activity of stressed plants exceeded that of controls during the whole development and reached the maxima at the last sampling of treated plants.
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Accumulation of uranium by plants cultivated under laboratory conditions
Buzek, Martin ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
The ability to accumulate uranium was tested on 20 different cultivars and GMOs of Nicotiana spp. grown in Hoagland's hydroponic medium indoors. Apart from the accumulation and translocation of uranium in plants, the effects of genetic modifications and adaptations of hydroponic medium on the ability of plants to accumulate uranium were tested. N. glauca, N. tabacum cv. M 51 and GMO M 51 Pro seemed to be the best plants for accumulation of uranium. Concentrations of uranium in these plants grown in medium with 0,5 mM of uranium were as high as 31.28 mg/g dry weight in roots and 0.21 mg/g in upper parts. N. tabacum cv. La Burley 21 and GMOs TRI2 - T1 and TRI2 - T2 were tested for accumulation and translocation of uranium. Highest concentration was 72.49 mg/g in roots, 4 mg/g in stems and 1.1 mg/g in highest leaves for plants cultivated in medium with 1 mM of uranium. Absence of phosphate in the hydroponic medium resulted in increased accumulation of uranium.
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Stereologická metoda pro odhad povrchu tylakoidů chloroplastu
Kubínová, Lucie ; Kutík, J.
The stereological method using “local vertical windows” applied to the estimation of thylakoid surface area in the chloroplast volume, based on evaluation of chloroplast electron micrographs is presented. The method is demonstrated on the study of chloroplast ultrastructure in the leaves of plants of CE704 maize (Zea mays L.) line, developing in control and chilling conditions
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Determination of Natural Compounds in Select Plant Materials and Less Obvious Kinds of Fruit
Hohnová, Barbora ; Márová, Ivana (referee) ; Ventura, Karel (referee) ; Omelková, Jiřina (advisor)
Flavonoids are natural compounds widely distributed in plant kingdom. They are inseparable from human diet because they showed a protective effect against cancer, stroke and coronary heart diseases related to their antioxidant properties. Therefore, rapid and efficient extraction procedure prior to chromatographic analysis is required. The liquid extraction at elevated temperature and pressure – Pressurized fluid extraction (PFE) and Pressurized hot water extraction (PHWE), present fast, effective and environmentally friendly extraction methods for the determination of flavonoids in plant materials. PFE and PHWE followed by reversed phase high-performance liquid chromatography with UV-visible detection have been utilized for the determination of a group of flavonoids (rutin, myricetin, quercetin, luteolin, apigenin and kaempferol) in the leaves and berries of less common plants. The matrices were extracted by methanol, ethanol and water at higher temperature 40-120 oC and pressure 15 MPa during 15 minutes. The obtained results were compared with conventional Soxhlet extraction and ultrasound-assisted extraction, the same solvents were used. The most effective extraction of selected flavonoids was achieved by PHWE. PFE showed the extraction yields comparable to those of the Soxhlet extraction, and the lowest extraction power was displayed by ultrasound-assisted extraction.
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Determination of kadmium content in plant tissue of Norway Spruce and European Beech after application of cadmium oxide nanoparticles
Svozilová, Eva ; Mikuška,, Pavel (referee) ; Večeřa, Zbyněk (advisor)
The aim of this thesis is to monitor cadmium content in needles of Norway spruce and European beech leaves after controlled exposure to cadmium oxide nanoparticles and evaluate the potential risks of such nanoparticles to plants. Needles and leaves were harvested after a one-week and two-week exposure and prior to analysis of cadmium content, they were modified using relevant procedures. Samples were mineralized in nitric acid using pressurized microwave mineralizer and subsequently analyzed by atomic absorption spectrometry (AAS) with electrothermal atomization of cadmium content. Based on the results AAS analysis the transport of nanoparticles into the plant tissue of studied species was evaluated, comparing the content of cadmium in one week and two weeks experiment in the washed and unwashed samples of needles and leaves.
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