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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Studium alelopatických vlastností druhů rodu netýkavka (Impatiens L.) / Study of allelopathic effects in species of Impatiens genus (Impatiens L.)

KREJČOVÁ, Jana January 2009 (has links)
All three jewelweeds species (Impatiens. L.)contain series of secondary metabolites from category of phenolic substances, e.g. naphthoquinones. This substances belong to allelochemicals, they can to affect germinability and growth of other plants. The extracts from jewelweeds (leaves, roots) and their fractions can to affect negatively germinability and growth of the chosen weed's seeds. Knowledges of allelopathic effects in jewelweeds species on other plants might be of important impact on ecological farming in the implementing of alternative herbicides.
52

Biologická aktivita obsahových látek rostlin XXXIV. Alkaloidy nati Glaucium flavum CRANTZ a jejich vliv na lidské cholinesterasy / Biological activity of plant metabolites XXXIV. Alkaloids from the herb of Glaucium flavum CRANTZ and their impact on human cholinesterases

Puzyrevská, Jana January 2017 (has links)
Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Botany and Ecology Candidate: Jana Puzyrevská Supervisor: PharmDr. Anna Hošťálková, Ph.D. Title of Thesis: Biological activity of plant metabolites XXXIV. Alkaloids from the herb of Glaucium flavum CRANTZ and their impact on human cholinesterases. Key words: Glaucium flavum Crantz, cataline, N-methyllaurotetanine, norchelidonine, protopine, AChE, BuChE. Alzheimer's disease, the most widespread neurodegenerative disease, causes decrease of cognitive functions and dementia. The most effective therapeutic approach is the application of central cholinesterase inhibitors, which alleviate cholinergic deficit in brain and thus improve memory. Currently, intensive investigation of new active compounds including natural substances is carried on. Within the preliminary testing, alkaloid extract from Glaucium flavum Crantz herb showed promising inhibition of human cholinesterases, so it was selected for further examination. The primary alkaloid extract was acquired from dried flowering herb by extraction with ethanol and subsequent liquid extraction at different pH. This extract was treated by preparative thin layer chromatography. The structure of alkaloids was determined by spectrometric methods (MS, NMR) and their optical...
53

Výroba bionafty z použitých jedlých olejů / Biodiesel production from used edible oils

Menšíková, Petra January 2008 (has links)
This diploma thesis is engaged in considering of suitable technology for biodiesel production from used cooking oils. For the main parts of technology were made some mathematical models in a Chemcad programme. There was made a laboratory analysis of various samples of used cooking oil.
54

Studium vlastností různých rostlinných olejů / Study of quality of different vegetable oils

Martinů, Michaela January 2008 (has links)
The aim of the diploma thesis was determined the particular fatty characteristics of various vegetable oils in dependence on their storage life and storage conditions. Storage conditions were defined by room temperature and coolroom temperature. The fourteen oils were used for analyses, namely linseed oils, castor oil, grape seed oil, almond oil, olive oil, jojoba oil, avocado oil, apricot kernel oil, corn oil, rice bran oil, macadamia nut oil, soya bean oil, pumpkin seed oil and sunflower oil. All tested oils were supplied by firm M+H, Míča a Harašta s.r.o. The fatty characteristics included the saponification value, the acid value, the iodine value and the thiobarbituric value. The ester values and the percentage glycerol content were counted on the basis of the saponification value and the acid value. Time dependences of all fatty characteristics were figured to graphs and they were compared on various storage conditions. The fatty characteristics indicated lower values in storage of oil samples in coolroom than at laboratory temperature.
55

Změny obsahu mastných kyselin v rostlinných olejích během skladování / Changes of fatty acids content in vegetable oils during their storage

Bambasová, Lenka January 2008 (has links)
The aim of the diploma thesis was the identification of fatty acids contained in vegetable oils by gas chromatography. Amount of fatty acids was monitored in dependence on the duration and conditions of storage. Conditions for storage were selected at room temperature and refrigerator temperature. In total fourteen oils were analyzed - avocado oil, pumpkin seed oil, grape seed oil, jojoba oil, corn oil, linseed oil, macadamia oil, almond oil, apricot-stone oil, olive oil, castor oil, rice oil, sunflower oil and soya bean oil. Gas chromatography was applied for identification and quantification of fatty acids. Methanol esterification method using potassium hydroxide catalysis was chosen for preparing of the samples of the fatty acid methylesters. Eight fatty acids were observed in the vegetable oils : myristic, palmitic, palmitoleic, stearic, oleic, linoleic, gama-linolenic and linolenic acids.
56

Studium konzervačních systémů pro kosmetiku / Study of preservative systems for cosmetics

Šmétková, Zuzana January 2009 (has links)
The aim of this diploma thesis was to prove the antimicrobial actvivity of the selected syntetic preservatives used in cosmetics, such as methylparaben, butylparaben, phenoxyethanol, bronopol, imidazolidinyl urea and methylisothaizolinone, in different concentrations (up to the highest permitted concentration and in increased concentrations), and of some essential oils, which are possible to use in cosmetics (essential oil from Eucalyptus globulus, Pimpinella anisum, Lavandula officinalis, Rosmarinus officinalis, Foeniculum vulgare, Mentha piperita, Juniperus communis and Pinus sylvestris). The effect was investigated in every preservative system alone, in order to evaluate the spectrum and the rate of each one. As indicator microorganism was chosen Bacillus subtilis and Penicillium chrysogenum. The used methods was disk difusion method and modify difusion method. From synthetic preservatives had the best effects bronopol, imidazolidinyl urea and methylisothiazolinone. From chosen natural antimicrobails had the effect against both indicator microorganisms the Mentha piperita, Foeniculum vulgare and Juniperus communis extracts.
57

Studium transportu huminových látek skrz rostlinné kutikuly / Study on the transport of humic acids through the plant cuticles

Smilková, Marcela January 2014 (has links)
This diploma thesis is focused on foliar fertilization. It is nowadays one of the most widespread types of application of commercial fertilizers. Concern of this thesis is the study of plant cuticles as a thin layer on the leaves. These thin membranes are responsible for regulation of water transport and nutrients. Further function of plant cuticles is the mechanical protection of the outer part of the plant. Plant cuticles were characterized by fluorescence spectroscopy, classical optical microscopy and profilometry. The main aim of this thesis is the optimization and verification of experimental methodology aimed to the transport of commercial humic product through plant cuticles by simple diffusion techniques. The results obtained by presented diffusion techniques of humic product through plant cuticles were correlated with the same diffusion experiments through synthetic membranes with defined pore size and density. The study on transport of commercial humic product was realized in hydrogel medium by two different diffusion methods – non-stationary diffusion technique and diffusion couple. The important part of this diploma thesis is the characterization of supported hydrogel matrix by rheology tests, mercury intrusion porosimetry and scanned electron microscopy. Conclusions of this diploma thesis could be used for improving of efficiency of foliar fertilization.
58

Vliv derivátů pyrazinu na obsah sekundárních metabolitů v in vitro kulturách rostlin II. / The effect of pyrazine derivatives on secondary metabolites content in plant cultures in vitro II.

Hanzlíková, Tereza January 2020 (has links)
The main purpose of the theses was to find if the abiotic elicitor 2,4,6-trimethyl-N-(pyrazine- 2-yl)benzenesulfonamide has any influence on the secondary metabolites production in callus and suspension cultures of Hypericum perforatum L. The cultivation was taking place in the Murashige a Skoog (MS) nutrient medium enriched by the growth regulator - alpha-naphthyl acetic acid at the concentration of 1 mg.L-1 . The elicitor was added to the cultures at the three levels of concentration: c1= 100.0 mg/100 ml; c2= 10.0 mg/100 ml; c3= 1.00 mg/100 ml. The individual samples were taken after 6, 24, 48, 72 and 168 hours of the elicitor application. The control samples without the elicitor were taken after 6, 48 and 168 hours. The collected samples were dried and subsequently transformed into methanol extracts in order to determine secondary metabolites content (rutin, hyperoside and quercetin) by HPLC method. Release of these metabolites into nutrient media was also subject of this observation. The elicitation has influenced production of the secondary metabolites, particularly in callus cultures, wherein several statistically significant values, characterizing increase in their production, were measured. The highest content of rutin (0.169 mg.g-1 DW) was determined in callus culture after 168 hours when...
59

Porcelánová tvorba a její odraz v zahradním umění

Nováková, Milena January 2014 (has links)
The work deals with the history of the distinguished Haas family and points at a connection between porcelain and garden art elements. This work based on artistic summary knowledge of garden artifacts and porcelain art production, it characterises development and changes in gardens parallel to those in porcelain motifs and decor. The study interprets motifs of garden art through the originality analysis of porcelain in its form, function, shape and colour. It provides new knowledge and historical basis for their mutual continuity in the context of stable development that have not been published before. The study brings evidence of presumed influence of garden art on decoration and innovation in the porcelain production and vice versa. Summary of porcelain elements in gardens. Garden art reflection and plant motifs in porcelain art. Retrospect and perspective of a garden with porcelain.
60

Nové směry v technologii výroby mražených krémů

Kašparová, Aneta January 2019 (has links)
Diploma thesis deals with new technologies, which could be used in the ice cream manufacture. First three theoretical parts are about casual ingredients and ice cream manufacture process. Last two parts are dedicated to food with beneficial bacteria and how it influences human body. The practical part is devoted to ice cream manufacture from different milk based and plant based ice cream mixes with carob addition as a stabilizer and probiotics bacteria, which were incorporated to the mixes in different times of activations. Sensory evaluation proved, that replacement of milk has positive effect to the ice cream just as the probiotic incorporation, which causes pleasant yoghurt taste. Microbiological analysis proved sufficient content of living bacteria and therefore a benefical impact on human health.

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