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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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Influence of growing conditions on the biologically active substances of non-traditional leafy vegetables.
FRIEDBERGEROVÁ, Markéta
Currently, most of the vegetables that are produced on the European continent are released in greenhouses. This method offers a considerable number of advantages, such as lower amount of water and heat consumption, protection against pests or meteorological phenomena, such as hail, and thus higher yields. However, one of the major disadvantages of these devices is the fact that glass is not permeable to UV-B radiation, which supports the biosynthesis of flavonoids, substances that have beneficial antioxidant effects for the human organism. This undesirable effect can be eliminated by installing LED (Light-Emitting Diode) lighting in greenhouses. This is because these lights provide a wide spectrum of electromagnetic radiation, i.e. wavelengths that plants use for a whole range of their processes. In this diploma thesis, the influence of growing conditions on the content of biologically active substances, especially quercetin and kaempferol in non-traditional types of Asian leafy vegetables, namely Namenia, Sagami, Golden Lion, Choy Sum and Tatsoi, was investigated. All the mentioned varieties were grown in two crops (spring and autumn) in the greenhouse and on the seedbed in the years 2019-2021. The highest concentration of total quercetin was recorded in the spring seed of Namenia grown in 2019 on the seedbed 1241 mg/kg of dry matter. Also, the highest content of total kaempferol 1753 mg/kg of dry matter was found in Namenia, it was the autumn period of 2020, also grown in a seedbed. When converted to fresh weight, the results were the same, the value for quercetin was 103 mg/kg of fresh weight and for kaempferol 142 mg/kg of fresh weight.
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Biologicky aktivní látky v netradiční listové zelenině.
FRIEDBERGEROVÁ, Markéta
Flavonoids are now increasingly coming to the forefront of interest not only from the scientific community but also of the public. They were found to be very beneficial in the field of prevention of cardiovascular or cancer diseases. In addition, they have proven to have antioxidant, anti-allergic or anti-inflammatory effects. In this bachelor 's thesis, the contents of substances, namely quercetin, kaempferol, morin, myricetin, apigenin and luteolin, were investigated using HPLC method. Lyophilized material of four varieties of Asian leafy vegetable from the cruciferous family was selected for analysis: Namenia, Sagami, Golden Lion and Tatsoi. All samples were grown in spring and autumn sowing period. Only two of the monitored aglycones, quercetin and kaempferol, were determined. The highest content of total quercetin was registered in the autumn sowing period of Namenia 1360 mg/kg of dry matter, the content of total kaempferol 1300 mg/kg of dry matter in the Golden Lion variety, also in autumn sowing period. After conversion to fresh mass, the highest concentrations of both aglycones were measured in Namenia during autumn sowing period. The amount of quercetin was determined to be 157 mg/kg of fresh weight, while the kaempferol content was 114 mg/kg of fresh weight.
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Monitoring of biologically active substances in Asian vegetables from Brassicaceae family
SVOBODOVÁ, Martina
The Bachelor thesis is monitoring the content of polyphenolic substances in non-traditional leafy vegetables at different times of the year. Specific samples were experimentally studied, such as: green mustard (Brassica rapa var. komatsuna), red mustard (Brassica juncea (L.) Czern.), mizuna and mibuna (Brassica rapa ssp. Japonica (L.)). Although the samples are Asian leafy vegetables, they are now widely used in the Czech Republic and can be found both in the form of seeds and as leaves for consumption. Therefore, the issue of beneficial biologically active substances is topical. The phenolic group includes flavonoids that are easily available and their biological activity is also significant. Vegetables have antioxidant properties due to flavonoids, which prevent lipid peroxidation and eliminate free radicals. This property is also beneficial to humans, and therefore flavonoid substances are also used in medicine. They can prevent the emergence of chronic diseases such as cardiovascular disease or atherosclerosis. Flavonoids are also attributed to preventive effects against cancer and diabetes mellitus. Samples of cruciferous leafy vegetables were grown in 2017 on the experimental plot of the Faculty of Agriculture of the University of South Bohemia in České Budějovice on the open area of the flowerbed in spring and autumn sowing. The high performance liquid chromatography method was used to measure the content of flavonoid substances. The following substances were studied in selected vegetables: myricetin, morin, luteolin, quercetin, apigenin and kaempferol. Unfortunately, myricetin, morin, luteolin and apigenin were not detected by HPLC. Concentrations of only quercetin and kaempferol were measured for final comparison with expert articles. The sowing time did not affect the measured contents quercetin and kaempferol in most of the samples. Only a specimen of Chinese red mustard from autumn sowing contained more biologically active substances.
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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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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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