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Our work was focused on the study of antioxidant ingredients contained in dealcoholised selected wines. For the experiment, three were selected samples of white, pink, three and three red wines, each of the values alcohol 0,1 %, 5 % and 12 % alcohol. Using a high-performance liquid chromatography were identified important antioxidants, specifically gallic acid, vanillic acid, syringic acid, caftaric acid, caffeic acid, p-coumaric acid, fertaric acid, ferulic acid, catechin, epicatechin, cis-resveratrol, rutin, quercitrin, tyrosol and quercetin. Spectrophotometry was also used for the determination of antioxidant activity, contents of total polyphenols, flavonoids and hydroxycinnamic acids. The results of this study can be said that the content of antioxidant components in dealcoholised wines and a "normal" order of the wines was similar values.

Thesis on the topic Antioxidant in herbal teas is divided into two parts. The first part theortical is concerned with the description and division of antioxidants. There are mentioned some synthetic antioxidants, some major intracellular antioxidant and natural antioxidant, which are represented by polyphenolic compounds as the main components of herbal teas. Furthmore, there is described the determination of biologically active compounds by extraction techniques to chromatographic methods. In the theoretical part are also described individual samples of herbs used for analysis. The second part is concerned with the practical determination of polyphenolic acids in selected samples of herbal teas. Two extraction techniques were chosen for separation of polyphenolics acids. The first was Soxhlet extraction accelerated and the second was exctraction shaker. For the determination of polyphenolic acids was used high performance liquid chromatography (HPLC) coupled with a diode array detector (DAD) and with mass detector type triple quadrupole. The measured results show that in most samples of herbs were the most represented chlorogenic acid and caffeic acid.

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It is known, that grape seeds are rich in significant antioxidant. The issue of dealing with the analysis and comparison of antioxidant components in the seeds of Vitis vinifera in the individual varieties has not been sufficiently studied, yet. In the first part of the thesis is an extensive literature focused on a summary of the work, which study substances in the vine seeds and their effect on human health. Experimental work is focused on the study of antioxidant components in the seeds of Vitis vinifera. The experiment was used extracts of the three "normal" (Frankova, Ryzlink vlašský and Cabernet Moravia) and three interspecific varieties (Nativa, Marlen and Kofranka). Spectrometric, using three fundamentally different methods - DPPH, ABTS and FRAP was determined antioxidant activity . Spectrophotometry was further investigated the content of total polyphenolic compounds and total content of flavanols . Technique of high- performance liquid chromatography with mass spectroscopy were analyzed nine major flavonoids (apigenin, astragalin, hyperoside, isorhamnetin, kaempferol, myricetin, quercetin, quercitrin and rutin) and two procyanidins (procyanidin A2 and procyanidin B1). The highest values of antioxidant reached interspecific varieties Marlen and Nativa, at the least antioxidant components were recorded in the variety Cabernet Moravia. However, in complex evaluation, between studied of varieties were not significant differences.

Phenolic substances are synthesized in plants, where they help in their defense against fungal diseases, are used as a significant source of substances by the human population. Phenolic substances are not a human organism capable of producing themselves and it is therefore necessary to take these health benefits in the diet. Grape vines, berries, are very rich in natural phenolic substances. We divide these natural phenolic substances into two basic groups: flavonoid and non-flavonoid, which, thanks to the technology of grapevine processing, pass into wine. Thanks to different grape processing technology, red wine is richer in phenolic content, but the content of these antioxidant components is not negligible even in white wines. Grape vines and their wine products are constantly being studied for the content of antioxidant components and their importance for human health, thanks to the development of modern analytical methods. The results of scientific studies are constantly updated and accepted not only by human health experts but also by the general public.

The thesis entitled Barrique wine deals in the teoretical part with technology of production of red wine from grape harvesting after wine training. This is followed by the ri-pening of wine in barrique special barrels whose chemical wood composition is described the same as its influence on the wine quality. Furthermore the thesis describes the chemical composition of wine and biologically active substances in barrique wines. The last chapter of the theoretical part deals with methods in the analysis of polyphenolic compounds. In the practical part the work focuses on the identification of polyphenolic compounds in barrique wines. This happens in seven samples of wines and on the monitoring of changes in the content of substances during extraction of oak chips in ethanol. For detection High performance liquid chromatography in tandem with a mass spectrometry was used.

This thesis was focused on the possibility of secondary utilization of waste material from the wine industry to remove heavy metals from wastewater. In the theoretical part, there were discussed mainly the problems of heavy metals pollution including methods of their removal and ICP-OES detection. Furthermore, the waste material from the wine production and the possibilities of its further processing were discussed there. The primary objective of the experimental part was to characterize the material by IR analysis, optimization of adsorption conditions, isotherms construction and determination of maximum adsorption capacities of white, red and chemically modified marc for Cd, Cr, Cu, Ni and Pb. From the parameters influencing the adsorption efficiency, the adsorbent load was optimized (m/V ratio = 0,02); pH values found were 5 for Cd, Cu, Ni, Pb and 3 for Cr and the contact time to reach the equilibrium was 15 minutes for Cd, Ni, Pb and 30 minutes for Cr and Cu. Maximum adsorption capacity for heavy metals were calculated from adsorption isotherms by applying the Langmuir model and found to be 18,829 7 mg/g for Cd; 10,664 7 mg/g for Ni; 35,602 0 mg/g for Pb (modified marc with 1M NaOH); 4,678 4 mg/g for Cu and 9,629 0 mg/g for Cr. The results of the work confirm the good adsorption potential of heavy metals on marc and the positive effect of chemical modification of natural biosorbents to improve their adsorption capacity.

The diploma thesis deals with the preparation of extract and concentrate of anthocyanin dyes from aronia moldings (Aronia melanocarpa). It also determines chemical properties important for human´s health, which are important also for further possible use of extract/concentrate as natural red food coloring. A series of extractions of dried and powdered aronia moldings was carried out in the experimental part of the thesis, aiming for the optimization the conditions of the extraction. Extracts were characterized by content of total anthocyans, content of total fenolic substances and total antioxidant activity. The best laboratory conditions for extraction were determined as follows: amount of moldings 12,5 g, composition of extraction agent ethanol:water 1:1, volume of extraction mixture 60 ml and time of the extraction 11 hours. Prepared extracts were concentrated on vacuum evaporator. It has been found that the temperature of the water bath in the vacuum evaporator can not exceed 40 °C. At higher temperatures there is significant degradation of anthocyanins. Furthemore, the content of individual anthocyanic dyes in extract and concentrate, from aronia moldings, was quantified by HPLC. The major anthocyanin, cyanidine-3-galactoside, was contained in the concentrate at 923,6 ± 8,5 mg·l-1, the other specified anthocyanin, minor cyanidine-3-glucoside, was present at a concentration of 53,5 ± 0,3 mg·l-1.