National Repository of Grey Literature 6 records found  Search took 0.00 seconds. 
Fenolické látky vo vybraných rastlinných druhoch
Boško, Rastislav
This diploma thesis deals with the analysis of phenolic compounds such as phenolic acids and flavonoids in selected plants, such as ribwort plantain (Plantago lanceolata L.) in which the content of chlorogenic acid, caffeic acid, verbascoside, ferulic acid, rutin and quercetin was monitored. The content of chlorogenic acid, coffee acid, routine, hyperoside, isoquercitroside, tiliroside, quercetin and kaempferol was monitored in small-leaved lime (Tilia cordata Mill.) In addition, the content of chlorogenic acid, caffeic acid, coumaric acid, rutin, hyperoside, isoquercitroside, quercetin and kaempferol was monitored in marigold (Calendula officinalis L.). Also the content of chlorogenic acid, coffee acid, rutin, hyperoside, isoquercitroside, quercetin and kaempferol was monitored in elderberry (Sambucus nigra L.). Similarly the extraction of phenolic compounds from these plants was carried out and subsequently subjected to chromatographic analysis on a UPLC liquid chromatograph with a PDA detector at the Research Institute of Brewing and Malting, Plc.
Preparation and characterization of extract from elderberry flowers
Lukšová, Leona ; Zemanová, Jana (referee) ; Vespalcová, Milena (advisor)
This diploma thesis deals with the determination of conditions for the preparation of elderberry extract so that the prepared extract retains as many biologically active substances as possible and the way of preserving this extract. Furthermore, the work deals with the transmittance of already specific phenolic acids, namely chlorogenic acid, coffee and ferulic skin, through the Franc diffusion cells. In the theoretical part of the thesis there is a taxonomic classification, description and use of elderberry. Furthermore, significant active substances, in particular phenolic acids, are mentioned. beneficial effects on the skin. The anatomy of the skin and the problem of the penetration of phenolic acids through the skin are described in detail. Finally, a description of high performance liquid chromatography is provided. The experimental part is devoted to verification of optimal conditions for preparation of extract. The best option is to extract the flowers with water at 100 ° C for 10 minutes in a ratio of 1 part by weight of dry flowers and 10 parts by volume boiling water. The ratio of flowers and stems to the phenolic acid content of the extract was also investigated. In the flower extract and its thickened version, the skin permeability was examined by transdermal absorption. The aim of this experiment was to find out if and how much the above mentioned phenolic acids go through the skin. As skin membrane, pork skin from the auricle was used. All determinations of the above phenolic acids in all samples were carried out by liquid chromatography.
Developement and optimization of the method for the extraction of ferulic acid from wheat bran
Hubačová, Klára ; Štursa, Václav (referee) ; Pořízka, Jaromír (advisor)
Bachelor thesis is considering usage of wheat bran for an extraction of ferulic acid. Wheat bran is a large-scale by-product of milling industry which is produced during milling of cereals (wheat) into flour. This low-cost product is usually used as a livestock feed. An initiative is raised for some other potential applications, because too large quantity produced every year can not be consumed just as a feed. There is a significant amount of phenolic acids from which ferulic acid is the most abundant one. It was found out after examination of structure of the wheat bran. This acid is connected with polysaccharides of a cell wall. The alkaline hydrolysis was used to disrupt a linkage between ferulic acid and polysaccharides. Then ethanol was added to precipitate the polysaccharides and the mixture was filtered. The filtrate contains ferulic acid which has great health benefits such as anti-inflammatory, antioxidant, anti-carcinogenic, antimicrobial effect etc. It plays an important role as an agent against UV radiation in the cosmetic products.
Stanovení flavonoidních látek ve vybraných druzích léčivých rostlin používaných v potravinářství
Bačová, Romana
In plant and food research the functional significance of herbs, spices and other plants, including their components is very popular topic. Plant material contains many components that are beneficial to human health by reducing the risk of chronic degenerative diseases. It is necessary to define the individual substances to understand and explain their biological effects. The first part of thesis describes the selected plants (elderberry, nettle, marigold, milk thistle, sea buckthorn, sage, purple coneflower and thyme) and also describes their medicinal properties and uses. The second part of thesis deals with phenolic and flavonoid substances. In the third (experimental) part, of thesis there were qualitatively and quantitatively determined flavonoid compounds in selected plant species. For identification the technique combining liquid chromatography and mass spectrometry - HPLC/MS was used. Extraction was carried out by vortexing and Soxhlet method, using two different concentrations of metanol. These metods were then statistically compared.
Changeof phenolic acids content during malting of spring barley
Štýblová, Romana ; Janoušková, Eva (referee) ; Běláková, Sylvie (advisor)
This bachelor thesis deals with detection of chosen phenolic acids (sinapic acid, caffeic acid, ferulic acid, syringic acid, p – hydroxybenzoic acid, vanillic acid and p – coumaric acid) in the malting barley and monitoring of their changes during making a malt in real enviroment of floor malt house. Tehoretical part describes individual phenolic acids, their presentation in raw material for making of malt and methods for determination . There is described technology of making a malt. The nine samples was taken in experimental part. There were a malting barley, intermediate products of malting, malt and rootlets. Phenolic acids were extracted by alkaline and acid hydrolysis. This samples were detected by Ultra high – performance liquid chromatography using of UV detection (UPLC/PDA).
Leaf vegetable as a source of phenolic compounds with nutritional value.
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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