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Bioactive compounds in green spices
ARNOŠTOVÁ, Lucie
The bachelor thesis focuses on the determination of the total content of phenolic compounds, individual majority phenolic compounds and vitamin C, contained in sweet basil (Ocimum basilicum), coriander (Coriandrum sativum), dill (Anethum graveolens) and lovage (Levisticum officinale). Firstly, the total content of phenolic compounds was determined by spectrophotometric analysis using Folin Ciocalteau agent in extracts from fresh and dried herb samples. Afterwards, particular representatives of phenolic compounds in the lyophilized material were identified by high-performance liquid chromatography (HPLC). Then the content of vitamin C in fresh samples from all selected plants was measured using high-performance liquid chromatography (HPLC). The highest concentration of phenolic compounds was discovered in lovage. The highest content of particular phenolic substances, quercetin and kaempferol, was also proved in lovage.
Ověření schopnosti rašeliníkového pektinu inhibovat aktivitu půdních enzymů
CHROUSTOVÁ, Lucie
This work deals with the influence of sphagnan, a Sphagnum moss-derived pectin, on the activity of soil enzymes. The aim of this work is to verify the extent to which sphagnan inhibits the activity of pure (commercial) enzymes and enzymes extracted from peatland. The inhibitory effects of sphagnan were compared with the effects of another moss pectin isolated from Leucobryum glaucum and selected phenolic compounds (humic substances from peat water and gallic, tannic, sphagnum and 4-hydroxybenzoic acids).
Relationship between leaf biochemistry, physiology and specie's competitiveness in selected grasses of relict tundra in Krkonoše Mts.
Mamula, Petr Martin ; Lhotáková, Zuzana (advisor) ; Tylová, Edita (referee)
The Krkonoše (Giant Mountains) Arcto-Alpine Tundra is an area that is part of the Krkonoše National Park with a unique ecosystem and biodiversity. In history, this area was very fundamentally influenced by the intervention of man, who farmed here and thus caused the creation of today's rare matgrass (Nardus stricta L.) meadow ecosystem. Thanks to the low growth and sparse foliage of the matgrass, many other plant species grow in these matgrass meadows, which are often endemic and protected by the law. In recent years, however, the matgrass has been overgrown by other grasses, such as the hairy reed grass (Calamagrostis villosa J.F. Gmelin), which, due to its taller growth and dense canopy covering the surface, does not allow the growth of rare species such as matgrass. Therefore, the aim of this work was for matgrass (N. stricta) and three other selected species of grasses - tufted hair grass (Deschampsia cespitosa (L.) P. Beauv.), moor grass (Molinia caerulea (L.) Moench) and hairy reed grass (C. villosa), to identify, based on biochemical, structural and physiological foliar parameters, a parameter or a combination of parameters that could give competing fennel grasses a competitive advantage. Field research and collection of foliage samples, for subsequent laboratory processing, took place in...
Antioxidant properties of tobacco plants grown in vitro with different nitrogen sources
Vlčková, Denisa ; Ryšlavá, Helena (advisor) ; Kubíčková, Božena (referee)
The established concept of plant nutrition with NO3 − and NH4 + ions, as the only absorbable forms of nitrogen, has been expanded in recent years to find that some plants are also able to use amino acids and peptides as a nitrogen source. In this work, the content of proteins, phenolic compounds and flavonoids, antioxidant capacity and activity of antioxidant enzymes in leaf extracts of six groups of tobacco plants grown in vitro were observed. The nutrition of these plants varied in the form and concentration of nitrogenous compounds. The experimental groups included: control plants grown on complete Murashige-Skoog agar rich in NH4 + and NO3 − ions (MS), plants grown in the presence of NO3 − ions, with reduced nitrogen concentration compared to MS (AD), plants grown in the presence of casein hydrolysate as the sole nitrogen source (H), plants grown in presence of both NO3 − ions and casein hydrolysate (AD+H) and AD and H plants grown in the presence of polyethylene glycol simulating drought stress (AD+PEG and H+PEG). Of all groups, plants H showed the highest content of phenolic compounds and flavonoids and the highest values of antioxidant capacity and antioxidant enzyme activity (catalase, glutathione reductase, superoxide dismutase, total peroxidases, ascorbate peroxidase, glutathione-S-...
Use of wheat bran for fertilizer production
Maňáková, Helena ; Štursa,, Václav (referee) ; Diviš, Pavel (advisor)
This diploma thesis deals with the production of fertilizer from wheat bran and spent coffee grounds, which are produced in large quantities in the food industry. The efficiency of the removal of caffeine and phenolic substances from coffee grounds using the oxidation reason and the possibility of recycling the usable oxidizing effect were tested. We managed to oxidize almost all phenolic substances and a significant amount of caffeine from coffee grounds, even through the recycled oxidizing effect. Fertilizer in the form of pellets was subsequently formed from coffee grounds and bran. During pelleting, the optimal degree of wetting of the material was studied to achieve optimal yield of pellets and sufficiently strong pellets. Different ratios of substrates for pelletization were also studied and the quality of produced pellets was assessed. The content of macro and microelements in the prepared pellets was determined. Pellets have been shown to be a good source of elements important for plant growth.
Accumulation of phenolic compounds in Spirogyra in stress conditions
Ráček, Jan ; Pichrtová, Martina (advisor) ; Procházková, Lenka (referee)
Phenolic substances represent one of the major groups of secondary metabolites of higher plants that play a role in a number of biotic and abiotic interactions. Among algal groups, these substances are produced, for example, by conjugating algae (Zygnematophyceae), which are currently considered to be the closest living relatives of higher plants. The common function of phenolic substances is protection against the harmful effects of ultraviolet radiation, or even an excessive amount of photosynthetically active radiation, which was supported by the induction of their synthesis after exposure to UV radiation in several ecophysiological studies. However, the range of applied stress factors and their effect on changes in phenol levels is limited. In this diploma thesis, the genus Spirogyra, for which the chemical structure of a number of specific phenolic substances is known, was exposed to selected stress factors and their influence on cell morphology, maximum quantum yield Fv/Fm and quantity of phenolic substances was monitored. A significant increase was observed after application of UV-B radiation, higher level of PAR, low temperature and osmotic stress, while at high temperature this effect was not evident. Increased production upon UV-B exposure further underlines the importance of phenolic...
Isolation and characterization of beta-glucans of natural origin
Ratsilouskaya, Lizaveta ; Hoová, Julie (referee) ; Márová, Ivana (advisor)
The bachelor thesis deals with the characterization of natural beta-glucans and other active substances isolated from macroalgae and yeasts. The used macroalgae samples differ in the pigment, origin and method of algae processing. The theoretical part focuses on seaweed and yeast species, beta-glucans, their sources and biological effects, other biologically active substances (such as polyphenols and antioxidants) and finally on methods for determining these biologically active substances. In the practical part, samples of selected macroalgae were analyzed, namely samples of Arame, Nori, Kombu, Wakame, Hijiki and Spaghetti. Aqueous, ethanol and acetone extracts of these algae were prepared in this work. The aqueous extracts were used for spectrophotometric determination of phenolic substances, flavonoids and antioxidant activity by the ABTS method. Furthermore, ethanol and acetone extracts of said macroalgae were used to determine total chlorophyll and carotenoid content spectrophotometric. The work also focused on beta-glucan content, analyzing macroalgae and yeast R. toruloides. Arame and Nori algae and R. toruloides were high in beta-glucans. However, beta-glucans were very low in other macroalgae.
Pretreatment of hops for further processing in beer technology
Tichá, Anna ; Štursa, Václav (referee) ; Pořízka, Jaromír (advisor)
This diploma thesis deals with pre-treatment of hops for further processing in beer technology. In the experimental part of the work, the effect of low temperatures, as pre-treatment of hops, on the monitored parameters was observed. Three types of cold pretreatment were used. In two cases, the hop material was frozen using a freezer at -25 ° C and in the second case at -70 ° C. In the third case, the hop material was treated by contact with liquid nitrogen in combination with mechanical treatment. The variety of hop materiál was Žatecký poloraný červeňák, which were in the form of pellets or pressed hop cones. The total bitterness of the samples, the total content of phenolic substances, the total content of flavonoids, the antioxidant activity and the concentration of essential oils, specifically myrcene humulene and geraniol, were examined. The effect of pre-treatment was investigated during conventional worth boiling as well as dryhopping. The experimental part includes descriptions of the hopping process, descriptions of individual analytical methods. A parallel measurement was performed on each sample. Significant advantages or disadvantages of some of the pretreatments were not demonstrable, however, the most significant differences were observed in samples hopped with hops pretreated by freezing at -70 ° C, which had a positive effect on the amount of extracted essential oils during cold hops.
Determination of selected phenolic and volatile substances in tea and tea infusion
Stará, Kristýna ; Vítová, Eva (referee) ; Diviš, Pavel (advisor)
This diploma thesis deals with the determination of phenolic substances and volatile substances in teas and tea infusions. The work compares teas based on their production technology and country of origin. Phenolic substances were determined by LC / MS. Phenolic substances were divided into catechins and other substances. In methanol extracts, green teas contained higher concentrations of catechins than black teas. From the group of catechins, the highest concentration was found for epigallocatechin gallate in green tea, namely 7,96 mg / g. Black teas contained the most gallic acid of the studied teas. The highest content of gallic acid in black teas was set at 1,84 mg / g. Tea infusions were prepared according to the classic procedures typical for each type of tea. In the infusions, the concentrations of all substances were higher in black teas. Some substances such as gallocatechin gallate, quercetin, coumaric acid and kaempferol were not detected in the infusions of green tea. Volatiles were analyzed by HS-SPME-GC-MS. The aroma of the tea was characterized by the identification of volatile substances in tea leafs. The black teas were characterized by a rich floral and sweet aroma. The green teas were more of a fresh and grassy aroma. The substances linalool, linalyl anthranilate and -Terpinyl acetate were found in all teas.
Encapsulation of active substances and possibilities of their application in anti-aging products
Horváthová, Iveta ; Němcová, Andrea (referee) ; Skoumalová, Petra (advisor)
The aims of this thesis were encapsulation of selected active substances and their possible application in cosmetic products with anti-aging effects. 6 kinds of active substances were studied – lipophilic vitamin E and vitamin A, hydrophilic vitamin B1 and vitamin B2, and phenolic compounds ferulic acid and chlorogenic acid. In theoretocal part, the general characteristics of active compounds and their use are described. It also includes the description of used methods. Practical part was focused on characterisation of active compounds from the perspective of antioxidant activity and encapsulation into liposomes from soy and sunflower lecithin. Encapsulation effectivity, size, stability and long-term stability of liposomes after four weeks were determined. The most suitable liposomes with active compounds were also tested for safety on human skin cells using the MTT test of cytotoxicity on keratinocytes HaCaT. Furthernore, 3 types of cosmetic products were prepared – day cream, night cream and skin serum. Each kind of cosmetic product was devided into 4 types – the product without any active compounds, the product containing free active compounds, the product with liposomes with active compouds and the product containing empty liposomes. As active compounds all our tested substances were used. Final products were tested 14 days on 15 female volunteers. Before and after products usage parametres of their skin were measured to analyze effect of products on skin rejuvenation. Volunteers were also rating sensory analysis of cosmetic products. The part of this thesis was also creating an online questionnaire about anti-aging cosmetics for publicity to find out the popularity of this kind of cosmetics.

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