This diploma thesis discusses the specifics of qvevri wine-making method, that represents very ancient footprint of wine technology. There are described and compared traditional wine-making methods with those which are used dominantly in wine-producing countries. The thesis deals with the chemical composition of wines vinified by different technologies. The knowlage gained from literary sources is compared eith the results of the experimental part.

The Czech republic belong to the north wine region in Europe. The begins of the viticulture started in the period of the Roman Empire, which is the proof of historici findings. The medical benefits of the wine is evidenced by the fact that the wine was a part of a pharmacopoeia in the 19th century. The wine started to be analyzed with the modern analytical methods and the chemical compounds in the wine started to be studied in detail. The phenolic are the natural part of the plants which act as antioxidants. Grapevine berries contain large amounts of phenolic compounds, which are divided into two basic groups. Non-flavonoid phenolics and flavonoid phenolics, which during the maceration getting into wine, where operates primarily on wine quality parameters and act as antioxidants for humans. In the experiment, the effects applied to the stopper component content of antioxidant in wine. The object of the experiment was a white wine (Pálava), pink and red wine (Frankovka). The wine was concluded various type of cap and stored for twelve months at two different temperatures.

The diploma thesis dealt with influence of oenological tannins on white wines. Total influence on sensory character and composition of wine.The teoretic part dealt with antioxidant substances in wine and with oenological tannis and their division and use.The pratical part deals with research of adding of seven types of commercial tannins to wine. The practical part summarizes results of sensory analysis include aromatic profil of wines. The charts with results are showing results of measurement of antiradical aktivity, reducing ability and amount of total phenols and catechins.

This thesis studies the effects of various concentrations of sodium chloride on growth and the content of secondary metabolites in the freshwater microalgae Chlamydomonas reinhardtii. The total content of phenolic compounds, flavonoids and total antioxidant capacity was analyzed by spectrophotometry. In the context of growth, also the content of photosynthetic pigments was determined. Further, the amount of selected metabolites was determined by HPLC/MS-MS. Cultivation of microalgae with increased NaCl inhibited cell growth and production of photosynthetic pigments. Conversely, higher levels of NaCl have proven to stimulate the synthesis of complete phenolic compounds and flavonoids. Similarly, the amount of phenolic acids was significantly influenced by the effect of increasing NaCl concentration, while the total antioxidant capacity of the microalgae also increased. These results confirm the involvement of phenolic compounds in the defense mechanism of unicellular algae Ch. reinhardtii against the observed stress factor.

Diploma thesis dealt with studying and evaluating the impact of fortification in different stages of maceration/fermentation on antioxidant properties of wine. The literary part of the work was clearly described chapters on various production methods and types of fortified wines, different classes of phenolic substances present in wine and study of antioxidant activity of wine and methods of assessment. In the practical part, were selected three blue grape variety from which it was successively produced 9 samples fortified wines. Time fortification took place in three different stages of maceration. The first was the fortification to the must before the start of fermentation, a second fortification during the fermentation of sugar - fermentation to about 7 % by volume alcohol, and the third fortification after fermentation in young dry wine. Fortification was carried out by adding the calculated amount of spirit in the volume of wine or must, at the same level of spirituosity all the resulting wine samples. After some time joining the distillate was carried out basic analysis of wine samples and determination of the profile of phenolic compounds. Spectrophotometric method was further assessed total content of phenolic compounds, flavanols, anthocyanins and antioxidant activity, which was determined by two different methods. Basic analysis and spectrophotometric measurements were performed in triplicate and the results were averaged. Samples of fortified wines were finally sensory evaluated participation of 12 tasters, and all the results summarized in tables and graphs, statistically evaluated and described in drawing conclusions for practical use.

Nowadays the study of phenolic compounds and their content in food is of great interest due to their versatile capabilities, and above all their beneficial influence on human health. According to numerous research works phenolic compounds are able to decrease the level of cardiovascular diseases, and they have bactericidal, fungistatic, antioxidant and vitamin properties. Most authors agree that vineyard site, as a combination of soil-climatic conditions, and rootstocks have a significant influence on accumulation and distribution of phenolic compounds. That is why the influence of different vineyard site and rootstocks on content of various phenolic compounds and spectrophotometric indexes of must and wine of new interspecific grape varieties was studied. The results of our research allowed us to choose the best rootstock and vineyard site for each variety. The comparison with control varieties showed that the influence of the year on content of individual phenolic compounds is more prominent than the influence of studied factors (vineyard sites and rootstocks). The knowledge in that area could help to select and recommend certain vineyard sites and rootstocks for those varieties. The choice will be based both on the quality of must and wine and on the potentially positive influence on human health. The correlation of the antioxidant properties with the principal polyphenols showed that individual compounds are weakly associated with all antioxidant parameters, suggesting that the expression of antioxidant activity is rather a consequence of synergism between various phenolics, and it is not simply attributed to specific constituents. On the other hand a strong positive correlation of AAR in grape juice and catechin content was established, these data indicate that catechin is likely to play a major role in antioxidant activity of grapes.

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.

Plant optical signals can serve as important source of information about biochemical and physiological processes in plants. These signals are influenced by compounds synthesized by plants during primary or secondary metabolism and thus, can also serve as their qualitative and quantitative indicators. Light reaching plant surface (leaf or fruit) can undergo three main pathways- it can be (i) reflected, (ii) absorbed or it can (iii) transmit through plant material. The probability of these three processes depends on particular wavelength of incident irradiation and on the morphological characteristics of plant tissues themselves. As such, plant contains various spectrum of photosynthetic pigments and fluorescent compounds which can either reflect, absorb or pass incident irradiation through at specific wavelengths. Biophysical techniques working with these optical properties of plant pigments and/or other compounds have become universal and common tool in basic and applied research. To quote some example, chlorophyll fluorescence imaging, UV induced fluorescence or spectroscopic techniques are on the top of interest thanks to its non-invasive nature, allowing maintain the integrity of measured cells or the whole plant constituents. The main aim of this thesis is to provide a comprehensive study on the possibility of non-invasive monitoring of phenolic compounds in the leaves and fruits.

The thesis deals with testing the antimicrobial activity of the seed extracts from grapevine, in the research data summary of biologically active substances contained in the vine seed (Vitis vinifera) and brief general characteristic of selected species of microorganisms. In the practical part of thesis was examined antimicrobial effect of seed extracts obtained from grape wine varieties grown in ČR. The first part of thesis deals with the process of producing extract. It was tested nonmethanol extract exposed to oxdiation, fresh methanol and nonmethanol extract in appropriate diluted concentrations. These extracts at 100 %, 50 %, 10 % concentrations were tested by using the agar difusion method, including Escherichia coli, Enterococcus faecalis and Candida tropicalis. All tested microorganisms were inhibited by the grape seed extracts using agar well difusion method and they were cultivated in their optimal conditions for the growth and reproduction after 24 hours and 48 hours. Finally were performed measurings of the inhibition zones.

The importance of monitoring the quality parameters (sugar content, titratable acid pH) in determining the optimum ripeness of blue grape varieties can be considered a method which provides only limited and inadequate information. To determine the required quality should be evaluated ripening grapes intended for the production of high quality red wines in addition to sensory methods and analytical methods which are able to define the change of phenolic compounds in berries and accordingly influence the determination of the harvest. The values of phenolic compounds vary significantly depending on the site and variety. My thesis tracks changes and development of phenolic compounds in berries, their relationship to quality and sensory parameters. It deals with the sensory evaluation method ripe berry grape seeds and also world-renowned analytical method "Glories", evaluating the level of phenolic compounds on selected varieties and habitats in South Moravia.