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Enzymatic and Metabolic Transformation of Silybin and its Congeners
Purchartová, Kateřina ; Křen, Vladimír (advisor) ; Macek, Tomáš (referee) ; Vítek, Libor (referee)
Natural flavonoids and flavonolignans feature beneficial properties for living organisms such as antioxidant and hepatoprotective effects, anticancer, chemoprotective, dermatoprotective and hypocholesterolemic activities. Their metabolism in mammals is complex, the exact structure of their metabolites still remains partly unclear and the standards are usually not commercially available. Hence, this project focused on the preparation of potential and defined biotransformation Phase II sulfated metabolites of silymarin flavonolignans: silybin, 2,3-dehydrosilybin, isosilybin, silychristin, silydianin and flavonoids quercetin, taxifolin, rutin and isoquercitrin. Pure sulfated derivatives were prepared using aryl sulfotransferase from Desulfitobacterium hafniense and aryl sulfotransferase from rat liver. Using heterologously expressed PAPS (3'-phosphoadenosine-5'-phosophosulfate) - independent arylsulfotransferase from Desulfitobacterium hafniense and cheap p-nitrophenyl sulfate as sulfate donor, sulfated flavonolignans and flavonoids were obtained in high yields. Silymarin flavonolignans afforded exclusively monosulfates at the position C-20 (C-19 in the case of silychristin), except 2,3-dehydrosilybin that yielded also the 7,20-O-disulfated derivative. Isoquercitrin and rutin were selectively sulfated...
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Enzymatic and Metabolic Transformation of Silybin and its Congeners
Purchartová, Kateřina
Natural flavonoids and flavonolignans feature beneficial properties for living organisms such as antioxidant and hepatoprotective effects, anticancer, chemoprotective, dermatoprotective and hypocholesterolemic activities. Their metabolism in mammals is complex, the exact structure of their metabolites still remains partly unclear and the standards are usually not commercially available. Hence, this project focused on the preparation of potential and defined biotransformation Phase II sulfated metabolites of silymarin flavonolignans: silybin, 2,3-dehydrosilybin, isosilybin, silychristin, silydianin and flavonoids quercetin, taxifolin, rutin and isoquercitrin. Pure sulfated derivatives were prepared using aryl sulfotransferase from Desulfitobacterium hafniense and aryl sulfotransferase from rat liver. Using heterologously expressed PAPS (3'-phosphoadenosine-5'-phosophosulfate) - independent arylsulfotransferase from Desulfitobacterium hafniense and cheap p-nitrophenyl sulfate as sulfate donor, sulfated flavonolignans and flavonoids were obtained in high yields. Silymarin flavonolignans afforded exclusively monosulfates at the position C-20 (C-19 in the case of silychristin), except 2,3-dehydrosilybin that yielded also the 7,20-O-disulfated derivative. Isoquercitrin and rutin were selectively sulfated...
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Biologically active phenolic compounds in selected vegetable in Allium genus.
STRÁNSKÁ, Lucie
This thesis deals with the content of polyphenolic compounds in vegetable of Allium species, which is mostly grown in the Czech Republic. It is Allium cepa, Allium x proliferum, Allium fistulosum, Allium tuberosum, Allium schoenoprasum, Allium porrum, Allium cepa var. agregatum. Polyphenols are micronutrients that have been identified in plants. These secondary metabolites involved the defence against pathogens or sunlight (Pandey, Rizvi, 2009). The studies that follow up these substances have been shown to play a significant role in the prevention of degenerative diseases such as cancer, cardiovascular diseases and neurodegenerative disease. The aim of this study was to determine the amount of myricetin, morin, luteolin, quercetin, apigenin and quercetin in selected types of vegetable grown in 2015 and 2016. The analysis was performed using high-performance liquid chromatography (HPLC). Samples were lyophilized in advance and ready for analysis. The analysis resulted in the chromatogram from which was then calculated content of selected material. Although the analysis should determine a total of six different compounds, only kaemferol and quercetin was specified because other substances in the sample weren ´t identified. In 2015 Allium x proliferum had the largest amount of quercetin (430? 10 mg/kg fresh weight) and Allium tuberosum contained the biggest kaemferol amount (170?105 mg/kg fresh weight). Analysis of the samples in 2016 has demonstrated different results. The most quercetin amount contained yellow onion with the value of 280?180 mg/kg fresh weight and the largest amount of kaemferol has again Allium tuberosum, 198?30 mg/kg fresh weight. These results were mainly influenced of climatic conditions, which in 2015 was a big drought and onion flourished. While 2016 year was a rather cooler and wetter.
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Content of rutin in the biological waste material from plantations of elderberry
Boháčová, Hana ; Vránová, Dana (referee) ; Vespalcová, Milena (advisor)
This thesis is focused on determining the concentration of rutin in twigs elderberry (Sambucus nigra L.). The theoretical part provides an overview of the properties, occurrence and use of elderberry in folk medicine, medicine and food. Furthermore, there are the most important substances contained in elderberry, especially flavonoids, including rutin and quercetin as well. There are briefly described their properties, biological effects and possibilities of determination. The content of the experimental part of the thesis was developed cheap extraction methods to obtain the maximum yield of dried twigs rutin elderberry. Rutin content was observed in twigs cultivated elder varieties and wild elderberry. The identification and quantification of rutin in extracts was optimized and validated method of high performance liquid chromatography (HPLC). As a comparative method to develop extraction was used a pressurized hot water extraction (PHWE). There were tested three particle sizes of shredded twigs. The particles were extracted differently hot water varying duration. Most rutin was found in samples milled at 4 mm particles. The optimum time and temperature of extraction was 7 hours at 80°C. The highest amount of rutin in bred elderberry was determined in a sample Mladší 2014, digestion using 1,49 ± 0,004 mg.100g-1 and method PHWE 5,75 ± 0,015 mg.100g-1. There was determined the most rutin in a sample Září 2014 in the wild variant of elderberry. By digestion of ground twigs was obtained 0,90 ± 0,022 mg.100g-1 of rutin, using PHWE 2,98 ± 0,022 mg.100g-1.
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Content of rutin in selected elderberry cultivars
Píšťková, Magdalena ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
The aim of this diploma thesis was to determine the rutin content in springs and leaves of 19 elderberry species (Sambucus nigra L.) with use of liquid chromatography. Furthermore the rutin content was determined in its significant sources – rue and buckwheat. The observed values were compared in order to answer the question whether it is useful to use the elderberry spring and leaves as a new source of rutin. Theoretical part of the thesis describes elderberry in general, its chemical composition and its usage in medicine. Following part concentrates on important substances contained in elderberry – flavonoids. Also principles of extraction techniques and HPLC are discussed. In practice the rutin was gained from plant matrix with use of pressurized hot water extraction (PHWE) which was performed in three five minutes long cycles. Conditions during the PHWE were set up to 80 °C and 150 bars. Obtained extract was purified with use of SPE columns and analyzed by HPLC with DAD detector (wave length – 360 nm). HPLC was performed with SUPELCOSILTMLC-8DB column. The mobile phase was composed of MeOH, H2O, and HCOOH in ration of 36:61,5:2,5. The set up flow of mobile phase was 1 ml/min. In the leaves the highest rutin content was determined in Pregarten – 26,34 ± 0,50 mg/g. On the other hand the lowest rutin content in leaves was determined in Körsör – 3,74 ± 0,13 mg/g. In springs the obtained results were as follow. The highest content was determined in Samyl – 4,87 ± 0,01 mg/g and the lowest content was determined in Heidegg 13 springs – 0,56 ± 0,01 mg/g. Also the HPLC detection limit – 6,3 . 10-5 mg/ml and quantitation limit – 2,1 . 10-4 mg/ml were determined for rutin.
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Extraction of selected elderberry flavonoids for food industry purposes
Grulichová, Hana ; Hrstka, Miroslav (referee) ; Vespalcová, Milena (advisor)
Amount of rutin and quercetin in bark and leaves from different type of Sambucus nigra was determined in this diploma thesis. Records of amounts were compared with amounts in significant sources of these flavonoids. Matters from raw matrix were obtained with pressurized solvent extraction (PSE) and pressurized hot water extraction (PHWE). There was use temperature 120°C, pressure 150 bar, three times 5-min cycles for PSE. There were used 80°C, 150 bar, three 5-min cycles for rutin extracted with PHWE and the same condition were used for extraction of quercetin only the temperature was changed to 100 °C. Analysis of rutin and quercetin were carry out high performance liquid chromatography (HPLC) with diode array detection (DAD), where was used SUPELCOSILTM LC 8DB column (5µm; 250 x 4.6 mm). Methanol: water: formic acid (36: 61.5: 2.5, pH 2.17 2.28) was used like a mobile phase. The flow of the mobile phase was set up 0.7 ml/min. Size of sample was 10 µl. The most amount of rutin was determined in the leaves of wild kind of Sambucus nigra with methanol extraction and hot water too. Extraction with PHWE was more effectively. There were determined 5.58 mg of rutin in one gram of sample from wild Sambucus nigra. There were determined the smallest amount of rutin in Sambucus nigra Körsör. There was found only 0.13 mg/g with extraction PHWE. The quercetin wasn’t determined in any Sambucus nigra leaves. There were found both of the flavonoids (rutin and quercetin) in the branch of Sambucus nigra. The rutin was determined in the small amount in wild kind but it was found in the important amount in Sambucus nigra cultivar. Whereas the quercetin was found in higher concentration than rutin when was finding the ideal conditions for extraction of branch. The quercetin was chosen like more important in light of amount. In the end the quercetin wasn’t detected in any Sambucus nigra cultivars. The most amount of quercetin was determined in wild sambucus nigra, 0.24 mg/g. The most amount of rutin was found in Sambucus nigra Albida, 2.33 mg/g.
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View of existing supplements for tissue of brain nutrition.
Fojtíková, Veronika ; Zemanová, Jana (referee) ; Vránová, Dana (advisor)
This diploma thesis is related to usage of food supplements in general. It observes which food supplements are mostly used, how often and in which period they are used and also which supplements forms population prefer. Next is this diploma paper focused on supplements for the support of cerebration, concretely up to supplements containing Ginkgo biloba. It studies their vascular activity, effect on memory and concentricity in various age groups. Also HPLC method for quick analysis of selected food supplements containing Ginkgo biloba was tested.
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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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Leaf vegetable as a source of phenolic compounds with nutritional value.
TRÖSTLOVÁ, Daniela
The present work treats the amount of phenolic substances in salad plants. A part of this vast plant group is made of flavonoids, which are important by their accessibility and significant biological activity. Quercetin and rutin are in the main focus of this work. They are noted for their favourable biological effects. Having antioxidant qualities, they prevent and stop the lipid peroxidation and they dispose of free radicals. Flavonoids are used in medicine and can prevent the formation of chronic diseases, such as cardiovascular disease or atherosclerosis. The amount of phenolic substances in the chosen sample of ten salad plants was determined by means of micellar electrokinetic capillary chromatography (MECC) and by high-performance liquid chromatography (HPLC). We have used a freeze-dried material for the analysis. The utmost amount of quercetin was found in lettuce grown on outside garden. 48 600 mg/kg of dry matter highly exceeded the amount of quercetin in other plants. There were other phenolic substancs as well: rosmarinic acid, caffeoylchinol acid and caffeic acid. Among others, we found derivatives and colourants of caffeic acid as well.
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Content of selected phenolic compounds in spice plants.
BERANOVÁ, Zuzana
This work concerns the amount of certain phenols in some of the representatives of families Alliaceae, Lamiaceae and Apiaceae. Phenols in plants are widely represented and highly concentrated. Flavonoids are one of the smallest, yet quite significant classes of phenols. Ingestion of food containing flavonoids can prevent certain diseases such as Arteriosclerosis. cardiovascular and tumor diseases. This work focuses, for their special biological effects, on five flavonoids: Kaempferol, Quercetin, Myricetin, Apigenin and Luteolin. For determining the content of phenols a method of High-performance liquid chromatography (HPLC) was used. Three representative of the family Alliaceae, two representatives of the family Lamiaceae and three representatives of the family Apiaceae were analysed. Only edible parts of the plants were used for the analysis and the amount of phenols was compared in certain plants planted in beddings to the plants planted in greenhouses. At first, the qualitative representantion of phenols was ascertained by the HPLC method. The result is chromatographic profiles, which were then used in calculating the amount of particular phenols. Then the total amounts of kaempferol, quercetin, myricetin, apigenin and luteolin were found out thanks to HPLC method. The biggest amount of total kaempferol was determined in petroselium hortense planted in beddings (588 mg/kg of fresh sample) and in a greenhouse (340 mg/kg of fresh sample). The biggest amount of quercetin was determined in red onion planted in a greenhouse (773 mg/kg of fresh sample) and in ocimum basilicum planted in beddings (535 mg/kg of fresh sample). The biggest amount of apigenin was determined in petroselium hortense planted in a greenhouse (1790 mg/kg of fresh sample) and in petroselium chrispum planted in beddings (3690 mg/kg of fresh sample).
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