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Possibility of determination of selected flavonoides
Smělá, Margita ; Vitoulová, Eva (referee) ; Vespalcová, Milena (advisor)
The theoretic part of the bachelor‘s thesis deals with description of selected flavonoids as apigenin, quercetin, luteolin, keampferol, rutin, myricetin and with options of their determinations. There were described typical properities and effects of several flavonoids at first. In the next part there are principles of methods, especially high-performance liquid chromatography and capillary electrophoresis. The biggest attention was made to literary survey of determination flavonoids coumpounds mentioned above, by high-performance liquid chromatography and capillary electroproresis. There were described the collection of plant material for extraction of flavonids in the practical part. The white and blue grapes were frozen by dry ice as soon as they were separated from a busch. Grapes were made in a nitrogenous atmosphere and lyophilizated after the frozen.
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Monitoring flavonoidních látek a karotenoidů ve vybraných doplňcích stravy
Hynštová, Veronika
Dietary food supplements are among the most rapidly growing sectors in the food product industry. The majority of consumers trust in the safety and efficacy of these products. For these reasons is a quality control required and analytical methodologies for this must be used. For identification and quantitative analysis four flavonoids diosmin, hesperidin, rutin and troxerutin in food supplements was used HPLC/MS method. For identification and quantitative analysis three carotenoids betacarotene, lutein and zeaxanthin in food supplements was used HPLC/UV/ViS/DAD method. Separation of flavonoids was achieved on the column ZORBAX POROSHELL 120 EC-C18 (50 x 4,6 mm, 2,7 um) and separation of carotenoids on the column ZORBAX SB CN (75 x 4,6 mm, 3,5 um). The amount of flavonoids and carotenoids in tablets and capsules was determined altogether in 12 different commercial preparations.
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The stability of biologically active compounds in elderberry (Sambucus nigra L.) inflorescence during processing
SUCHÁ, Renata
This thesis examines the stability of rutin in the inflorescences of the elder during processing. Elder (Sambucus nigra L.) is a medicinal plant that was used for medical purposes as early as in the Middle Ages. Both flowers (Flos Sambuci) and fruit (Fructus Sambuci) of the elder are on the list of official medicinal products of the State Institute for Drug Control. The main active phenolic substance is flavonoid rutin. Flavonoids are phenolic substances of plant origin. Among the best known properties of these substances is their antioxidant activity. They protect the low density blood lipoproteins from the oxidation modifications that cause the development of arteriosclerosis and hypertension. As a medical plant, the elder is used especially for the preparation of a medicinal drink. It is also commonly used as a material for the preparation of syrup. This product serves as a basis for a refreshing and tasty drink and lately is has also started to be sold in shops. For comparison, five single-flower syrups from the elderflower by different producers were bought. A method of preparation of the elderflower syrup was devised, based in one case on frozen elder inflorescences and in the other on dried inflorescences. The plant material came from wildly growing shrubs and it was collected in June 2013. Altogether, 8 syrups were prepared in the laboratory, 4 of them from fresh material and 4 from dried material. Two different methods were used. The first one was based on extraction using sugar solution, the second one on extraction using water solution where sugar was added afterwards. Another added substance was ethanol. The method for measuring the amount of rutin in the samples was a combination of two extraction steps. The first step was the usual exraction using aqueous methanol and the second step was extraction using a solid sorbent (SPE). The analysis of fresh and dried material concluded that dried elderflowers contain many times more rutin than fresh elder. Among the commercially produced syrups, the "Kitl Syrob Bezový" contained most rutin; a little less rutin was found in "Hamé Bylinný sirup Bezový květ". The concentration of rutin in the syrups prepared in the laboratory was much higher than in the commercial products. By using different methods of syrup preparation and their subsequent analysis, it was found that the syrups prepared from the dried inflorescences contained a higher amount of rutin than the syrups produced in the same way, but from frozen material. Addition of a small amount of ethanol had no effect on extraction of rutin from inflorescences. Free quercetin, which indicate a decomposition of rutin, wasn´t found in any of produced syrups. The produced syrups were used for the preparation of a drink and then underwent sensory analysis. The paired two-sided preference test included pairs of drinks consisting of a fresh elder drink and dried elder drink. The results showed that the evaluators preferred syrups from dried elderflowers in two of the cases, while in the other two evaluated pairs, the results were not statistically significant. In all cases, the evaluators most often found small and middle differences. The gained results show that the best method of syrup preparation uses dried plant material and sucrose solution as the extraction agent. The syrup prepared in this way contained most rutin and at the same time showed the smallest losses of this substance, which is beneficial to human health. Furthermore, it also tasted better in comparison with syrup prepared in the same way, but from fresh material.
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Optimization of conditions and procedures for plant extraction.
SMUTNÍKOVÁ, Kateřina
The thesis deals with the content of selected phenolic compounds in some species of the genus Amaranthus, in black elderberry (Sambucus nigra L.) and buckwheat (Fagopyrum esculentum M.). Phenolic compounds are a group of natural compounds exclusively vegetable character. Flavonoids represent only one group of phenolic compounds. Flavonoids show many positive biological effects, in particular act as antioxidants. Natural flavonoids may cause to prevent from coronary- heard diseases and other diseases associated with older age. In recent years the increased attention is paid to flavonoid investigation due to its biological effects. For the determination of phenolic substances there were used two independent analytical methods. There are the high-performance liquid chromatography (HPLC) and micellar electrokinetic capillary chromatography (MECC). The MECC method was used for determination rutin and free quercetin. The highest content of rutin was found in leaves of buckwheat (76,400 mg/kg of dry weight) and the lowest content of rutin was determined in buckwheat hulls. The highest content of rutin was observed in teas from buckwheat leaves and inflorescence. This amount of rutin corresponds with rutin content in more than two pills of Ascorutin (the most favourite flavonoid medicament in the Czech Republic) The HPLC method was used for quantitative determination of phenolic acids. The content of free quercetin was monitored in all samples. No free quercetin was found both in plant material and in samples of teas. The ethanolic extract from the elderberry inflorescence didn´t contain any free quercetin. Free quercetin wasn?t found in any further samples of teas, which were prepared by described methods.
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The content changes of selected phenolic compounds during processing of medicinal plants
GROŠAFTOVÁ, Blanka
This work was aimed to the problem of change of the content of selected phenolic substances during treatment and storage of medical plants. Flavonoids represent small, but very important group of phenolic compounds. The biggest attention was paid to quercetin and rutine.Content of phenolic substances was determined by method of micellar electrokinetic capillary chromatography (MECC) in case of 6 medicinal plants usually used in traditional and modern medicine.
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The content of selected phenolic compounds in representatives of Chenopodium L and Atriplex L genera.
DĚKANOVÁ, Zdeňka
The thesis deals with measuring the content of chosen phenolic substances in some specimen of the genera Chenopodium L. and Atriplex L. Two independent analytical methods were used to determine the content of phenolic substances, namely the Micellar Electrokinetic Capillary Chromatography (MECC) method and the High - Performance Liquid Chromatography (HPLC) method. Two cultured species of the genera Spinacia and Atriplex, three freely growing specimen of the genus Chenopodium and three freely growing species of the genus Atriplex were analysed. The analysis concerned the leaves and the inflorescence of these species.The total content of quercetin and rutin was determined by the MECC method. The highest total content of quercetin was found in the leaves of the Garden Orache (4240 mg/kg of dry matter), the lowest total content of quercetin was found in the inflorescence of the Atriplex prostrata DC. (19.6 mg/kg of dry matter). Rutin was only found in four samples, the rest of the samples contained rutin in quantities below the limit of quantification. The highest content of rutin was found in the leaves of the Lamb´s Quarters (868 mg/kg of dry matter).
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Influence of genotype on rutin content in plants from genus \kur{(Fagopyrum)}
KRÁLOVÁ, Martina
The bachelor work is focused on evaluation of the influence of buckwheat species and variety on rutin containt in particular plant parts, on the total rutin yield per hectare production and on comparison varietal differences between both species, common buckwheat \kur{(Fagopyrum)}esculentum)} Moench) and tartary buckwheat \kur{(Fagopyrum tataricum)}. Rutin is a flavonol (quercetin-3-O- rutinosid) which is also called P vitamin. As well as it is known as the permeability factor or factor allowing permeability of the blood vessel. Rutin stimulates the C vitamin effect. Rutin has as well a high influence on hypertension, hypercholesterolemia and other cardiovascular diseases due to antioxidant properties. Buckwheat is the most important source of rutin. It is annual plant which belongs to Polygonaceae family and has a beneficial effect on human body. The common grown type is common buckwheat \kur{(Fagopyrum)}esculentum)} Moench) and less used type is buckwheat tartary \kur{(Fagopyrum tataricum)}. Tartary buckwheat \kur{(Fagopyrum tataricum)} contains several times higher amount of rutin than common buckwheat \kur{(Fagopyrum)}esculentum)} Moench). The highest amount of rutin is presented in the leaves and blossoms and the lowest one in seeds. Tartary buckwheat \kur{(Fagopyrum tataricum)} has much higher amount of rutin in seeds than common buckwheat \kur{(Fagopyrum)}esculentum)} Moench). The varietal differences in rutin content are considerable.
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The rutin content in amaranth (Amaranthus sp.)
BERANOVÁ, Kristina
This work was aimed to the determination of the flavonoids of rutin in the leaves, stems and seeds of different kinds and species of amarant. Rutin is a phenolic substance, which belongs to big group of secondary plant metabolites. Most recently lot of attention is paid to quercetin and its glycoside {--} rutin because of its demonstrable positive effect on the human organism, mainly the antioxidant effects which prevents the atherosclerotic plaque and preroxidation of lipids and antiviral activities. The research orients to its potential anti-carcinogen activities. Thanks to these properties it became a common part of the human daily diet. Amarant could be a beneficial source of these substances. Content of rutin was determined by the micelar electrokinetic capillary chromatography (MECC) in the group of seven genotypes of amaranth. For the analysis a samples of leaves, stems and seeds were used, because of its high contents of flavonoids. The highest content of rutin was found in the leaves of the species A. cruentus {--} genotype Olpir (27 400 mg/kg of dry matter) and the lowest in the seeds of A. cruentus {--} genotype Monatana (25,3 mg/kg of dry matter). Results of this research are unique as they were never published before.
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The content of selected fenolic compounds in medicinal plants.
KREJČÍ, Zuzana
The work has been inquired into the problem of content determination of phenolic substances in medicinal plants traditionally used in Czech Republic. Phenolic substances belong to a group of natural compounds, which are purely plant origin. Flavonoids are a part of this extensive group of compounds. As for flavonoids, most attention is paid to quercetin and rutin. It is caused by their easy availability and very significant biological activity. These compounds embody a lot of positive biological effects. They have expressive antioxidant properties, inhibit lipid peroxidation, scavenge free oxygen radicals and bond into the chelates they inactivate some prooxidant metal ions. The latest researches have shown that thanks to their properties natural flavonoids can occurence of chronical diseases, such as arterosklerosis, cardiovascular or tumor disorder. Flavonoids are exploited both in traditional and modern medicine. Same other studies have evidenced that valuable sources of these biologically effective substances are traditionally used medicinal plants. Content of phenolic substances was determined by method of micellar electrokinetic capillary chromatography (MECC) and liquid chromatography (HPLC) in collection of 8 medicinal plants usually used in Czech Republic. For analysis was used freeze-dried and dried plant material. In freeze-dried material was found the highest content of total quercetin in Filipendula ulmaria L. (14200 mg/kg of dry weight) and in Betula pendula Roth. (11800 mg/kg of dry weight). The highest content of rutin contained Sambucus nigra L. (17700 mg/kg of dry weight). Similar values was measured in dried plant material. The content of total quercetin and rutin during drying was unchanged.
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