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Vegetable adaptogens - Schizandra chinensis
Pospíchalová, Lucie ; Půčková, Helena (referee) ; Kotlík, Josef (advisor)
This thesis deals with plant adaptogens (bioactive substances) in the plant Schisandra chinensis. The theoretical part is focused on characterization of the Schisandra genus, characterization of the Schisandra chinensis as a plant, its properties, occurrence and growing possibilities in the regional climate zone of the South Moravian Region as well as the use of this plant. Furthermore, adaptogens are described from a chemical point of view and their possible methods of isolation from individual parts of plants. The experimental part deals with extraction of fruits and leaves from plant Schisandra chinensis. Further, in the leaves extract was determined chlorophyll a, chlorophyll b and carotenoids by spectrophotometry, where the quantity of individual substances was confirmed for months April – May.
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Adaptogens in the Shizandra chinensis plant
Pospíchalová, Lucie ; Půčková, Helena (referee) ; Kotlík, Josef (advisor)
This diploma thesis deals with plant adaptogens (bioactive substances) in the plant Schisandra chinensis. The theoretical part is focused on characterization of the Schisandra genus, characterization of the Schisandra chinensis as a plant, its properties, occurrence and growing possibilities in the climate zone. Furthermore, The effects of these adaptogens on the organism and the prediction of possible use in food supplements are described. The experimental part deals with the extraction of fruits and leaves from plant Schisandra chinensis. Further, chlorophyll a, chlorophyll b in the leaves extract was determined by UV – VIS spectrophotometry, whereby the optimal amount 3:1 of chlorophyll was confirmed for the plants growing in optimal conditions. Finally, the concentration of the adaptogen schisandrin A in the dried fruits was from different kind of extraction measured by HPLC. In all fruits, schisandrin A was confirmed, but the amount is different in each sample.
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Sequential fractionation of organic matter of humic acid isolated from Leonardite
Krist, Tomáš ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The aim of the diploma thesis was to optimize the sequential fractionation method of organic matter to be used for physico-chemical characterization of extracted fractions. Humic acid isolated from oxidized brown coal of Leonardite was used as a source matrix of organic matter. An eluotropic series was assembled and sequential fractionation was performed by extraction on a Soxhlet apparatus. The original humic acid and fractions were characterized by elemental analysis (EA) and thermogravimetric analysis (TGA), followed by Fourier transform infrared spectrometry (FTIR), molecular absorption spectrometry (UV/VIS), fluorescence spectrometry and potentiometric titration. Atomic ratios were determined from the results of the elemental analysis. From the measured UV/Vis and fluorescence excitation and emission spectra, the absorption coefficients, resp. fluorescence coefficients. Used fractionation method proved to be a suitable method for studying HA structure. A total of 62 wt. % of initial materiál was extracted, indiivdual fraction amounted from 0.36–30.92 wt. %. From the results of the structural analysis, it is clear that with increasing polarity of the organic solvent, fractions with long aliphatic chains were first isolated and their aromaticity graddualy increased. Non-polar organic solvents were suitable for the extraction of lipid-like coumpounds, while the most polar organic fractions were rich in polar groups and their structual parameters were close to the original humic acid. The fraction extracted with acetonitrile was the most unique fraction. This fraction was rich on nitrogen and amine groups and was similar to protein-like structures. In the last two fractions, extracted with alcohols, a significant bathochromic shift typical of fluorophore type V was observed. Among other things, they were also characterized by a higher content of plant carbohydrate residues.
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Flame retarded polyolefins
Pařízek, Jan ; Poláček, Petr (referee) ; Kučera, František (advisor)
The theoretical part of the bachelor thesis deals with topics related to polyolefins and flammability of polymeric materials. The mechanisms of action of the most common flame retardants and methods of flame characterization are described. In the experimental part, polypropylene samples with flame retardants were prepared. The substances used were based on ammonium polyphosphate, melamine polyphosphate, aluminium hydroxide and expandable graphite. The samples were tested for flammability according to UL 94. Subsequently, the solubility of the polymer/flame retardant mixtures in water was investigated by Soxhlet extraction.
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Sequential fractionation of organic matter of humic acid isolated from Leonardite
Krist, Tomáš ; Doskočil, Leoš (referee) ; Enev, Vojtěch (advisor)
The aim of the diploma thesis was to optimize the sequential fractionation method of organic matter to be used for physico-chemical characterization of extracted fractions. Humic acid isolated from oxidized brown coal of Leonardite was used as a source matrix of organic matter. An eluotropic series was assembled and sequential fractionation was performed by extraction on a Soxhlet apparatus. The original humic acid and fractions were characterized by elemental analysis (EA) and thermogravimetric analysis (TGA), followed by Fourier transform infrared spectrometry (FTIR), molecular absorption spectrometry (UV/VIS), fluorescence spectrometry and potentiometric titration. Atomic ratios were determined from the results of the elemental analysis. From the measured UV/Vis and fluorescence excitation and emission spectra, the absorption coefficients, resp. fluorescence coefficients. Used fractionation method proved to be a suitable method for studying HA structure. A total of 62 wt. % of initial materiál was extracted, indiivdual fraction amounted from 0.36–30.92 wt. %. From the results of the structural analysis, it is clear that with increasing polarity of the organic solvent, fractions with long aliphatic chains were first isolated and their aromaticity graddualy increased. Non-polar organic solvents were suitable for the extraction of lipid-like coumpounds, while the most polar organic fractions were rich in polar groups and their structual parameters were close to the original humic acid. The fraction extracted with acetonitrile was the most unique fraction. This fraction was rich on nitrogen and amine groups and was similar to protein-like structures. In the last two fractions, extracted with alcohols, a significant bathochromic shift typical of fluorophore type V was observed. Among other things, they were also characterized by a higher content of plant carbohydrate residues.
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Adaptogens in the Shizandra chinensis plant
Pospíchalová, Lucie ; Půčková, Helena (referee) ; Kotlík, Josef (advisor)
This diploma thesis deals with plant adaptogens (bioactive substances) in the plant Schisandra chinensis. The theoretical part is focused on characterization of the Schisandra genus, characterization of the Schisandra chinensis as a plant, its properties, occurrence and growing possibilities in the climate zone. Furthermore, The effects of these adaptogens on the organism and the prediction of possible use in food supplements are described. The experimental part deals with the extraction of fruits and leaves from plant Schisandra chinensis. Further, chlorophyll a, chlorophyll b in the leaves extract was determined by UV – VIS spectrophotometry, whereby the optimal amount 3:1 of chlorophyll was confirmed for the plants growing in optimal conditions. Finally, the concentration of the adaptogen schisandrin A in the dried fruits was from different kind of extraction measured by HPLC. In all fruits, schisandrin A was confirmed, but the amount is different in each sample.
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Vegetable adaptogens - Schizandra chinensis
Pospíchalová, Lucie ; Půčková, Helena (referee) ; Kotlík, Josef (advisor)
This thesis deals with plant adaptogens (bioactive substances) in the plant Schisandra chinensis. The theoretical part is focused on characterization of the Schisandra genus, characterization of the Schisandra chinensis as a plant, its properties, occurrence and growing possibilities in the regional climate zone of the South Moravian Region as well as the use of this plant. Furthermore, adaptogens are described from a chemical point of view and their possible methods of isolation from individual parts of plants. The experimental part deals with extraction of fruits and leaves from plant Schisandra chinensis. Further, in the leaves extract was determined chlorophyll a, chlorophyll b and carotenoids by spectrophotometry, where the quantity of individual substances was confirmed for months April – May.
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Pressurized solvent extraction of plant material for food industry use
Holasová, Petra ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
Flavonoids were identified and quantified in samples of dry leaves of plant Stevia rebaudiana Bertoni. Content of flavonols (kaempherol, quercetin, myricetin, rutin) and flavons (apigenin, luteolin) were compared in three samples (standard leaves of Stevia rebaudiana Bertoni, Stevia rebaudiana Bertoni origin from Ukraine and from Czech republic), that were extracted by three extraction methods (PSE, ultrasonic extraction, Soxhlet extraction) with two polar solvents, methanol and ethanol, in combination with non-polar hexane. Extracts were analyzed by HPLC with detection UV-VIS. Antioxidant activity and total content of flavonoids in extracts were measured by spectrometry. Stable free radical DPPH. was used for determination of scavenging effect in extracts. PSE was the most effective extraction method with this conditions – 120 °C, dynamic mode and with methanol like solvent.
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Superkritická extrakce beta-sitosterolu ze slupek a listů rakytníku řešetlákového
Sajfrtová, Marie ; Sovová, Helena ; Bártlová, Milena
Extraction of beta-sitosterol with supercritical carbon dioxide from sea buckthorn pulp and leaves, a by-product of production of sea buckthorn juice, was studied. The effect of operation conditions on the yields and solubility of whole extract and its minor component beta-sitosterol was analysed in a series of experiments at pressures from 15 MPa to 28 MPa and temperatures 40 °C and 60 °C. The consecutively collected extract samples were analysed using HPLC. The selectivity of beta-sitosterol to major component was determined. The content of beta-sitosterol in both plant materials was obtained using Soxhlet extraction with hexane.
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