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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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Polyfenolické látky modrých hroznů a červeného vína a jejich význam ve výživě člověka
Šajtarová, Pavla
This bachelor thesis is focused on the topic Polyphenolic substances of blue grapes and red wine and their importance in the human nutrition. It was written from 2013--2014 at the Department of Post-Harvest Technology of Hurticultural Products, Faculty of Horticulture, Mendel University in Brno. Literary section pays attention to polyphenolic compounds contained in grapes and red wine. It describes their characteristic, chemical structure, formation, distribution and their antioxidant effect on the human organism. Experimental section analyzes antioxidant capacity, volume of anthocyanins and the total amount of polyphenols inside grapes, musts and wines of two varieties 'Cabernet Moravia' and 'Lemberger'. The results are presented in tables and expressed in graphs. Graphs show us the condition of observed factors in a process of grape processing into the wine and compare different samples, varieties and methods. Results are statistically evaluated and compared with other authors.
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Horticulture production in conditions of Sub-Sahara Africa
Milanda, Johannes
This paper was written to provide the literature review on the topic of horticultural production in Namibia or in neighboring countries, with a focus on vegetable species. To suggest a prospective representative vegetable species from the study area, which could have production potential in the Czech Republic. Four chosen cultivars (Metro, Nakare, Bira and Shidimba) from the Cowpea (Vigna uinguiculata L Walp) species were experimentally tested in conditions of the Czech Republic. They were grown naturally extensively with no fertilizers, herbicides or pesticides used. They're morphological parameters were then recorded and laboratory analyzed using ANOVA and three valuables [flavonoids, total antioxidants capacity (TAC) and polyphenols] were determined using different methods with the spectrophotometry.
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Flavonoidy a antioxidační aktivita červených vín
Vachová, Simona
The literary part of the thesis brings the insight into the issue of free radicals and their impact on the health of the organism. It deals with the specific abilities and the role of antioxidants in the protection against the negative impact of radicals. It also pays attention to flavonoids as major polyphenols in red wines which significantly influence the antioxidative activity, and thus the health benefits of wine. The practical part shows, using the spectrophotometric DPPH and FRAP methods, the comparison of antiradical activity and reducing power in selected samples of red wines made by different technologies of maceration. The results show the direct relationship between the maceration method and the measured values of the antioxidative potential of the red wines. The discussion and the final part of the thesis suggest new questions and possible directions for further research.
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Antioxidační účinky vybraného sortimentu léčivých, aromatických a kořeninových rostlin se zaměřením na dřeviny
Kolísková, Barbora
The literary section of this bachelor's thesis is aggregately dealing about substances with antioxidant effects which are located in medicinal trees and shrubs. The literary section also describes selected medicinal trees and shrubs. The practical experiment was based on assessment substances with antioxidant effects which are in selected medicinal trees and shrubs. It was analysed 16 species of fruit of medicinal trees and shrubs. Total antioxidat capacity, total phenolic content and total flavonoid content were determined The highest value of total antioxidant capacity was measured in Mespilus germanica 'Holandská'. The highest values of total phenolic content and total flavonoid content were determined in Rosa pommifera 'Karpatská'.
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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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The proposal of vinegar farm with the character of functional foods.
HRDINOVÁ, Vendula
The work is focused on the development of a new functional food . The functional food in addition to nutrient sources must clearly contribute to the health improvement thanks to another ingredient which must be of natural origin. I chose vinegar as the basic component in my work. The vinegar can be made in a vinegar manufacturer through classical oxidation technique of diluted ethanol solution by acetic bacteria on the large contact surface with air alcohol analysis . Diluted ethanol may well serve as alcohol analysis, but I used some weak cider. I prepared the cider from alcoholic fermentation of apple pulp waste extraction after its pressing. The cider was pressed together with water. Red onion extracts, as a rich source of flavonoids, work as metraceutikum and give this vinegar the
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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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