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In recent years, the use of natural medicinal properties of plants has again come to the forefront of interest of the public. Because of their therapeutic properties, these plants are commonly used in alternative treatments for minor ailments. This thesis deals with the determination of polyphenolic acids in extracts from aronia, echinacea, tetradenia and centella. One of the aims of the thesis was to compare the amount of polyphenolic acids in individual plants with their antioxidant properties. The theoretical part includes a general introduction to flavonoids, introduction to polyphenolic acids, introduction to the principles of capillary zone electrophoresis and a summary of selected foreign studies for the determination of flavonoids. An important chapter of the theoretical part is a description of individual plants with an explanation of their possible therapeutic use. The experimental part is devoted to the process of optimization of electrophoretic determination of selected polyphenolic acids and evaluation of their content. It was found that in the extracts six representatives of polyphenolic acids occur in minimal amounts, often below the limit of quantification or detection of the method.

This master thesis deals with preparation of extracts from fruits of aronia, optimization of conditions for extraction and subsequent characteristics of the obtained optimal extract. In the theoretical part information about the botanical characteristics of Aronia melanocarpa and about its utilization are mentioned. Furthermore, the chemical composition of aronia fruits is described and the main biologically active substances contained in the plant are described. At the end of the theoretical part extraction and separation techniques, determination methods of antioxidant, antimicrobial activity and determination of aromatic active compounds are described. The experimental part describes the optimization of maceration so that the macerate contains as much polyphenolic substances as possible, as well as aromatic active substances. 40% ethanol, at a temperature of 60 ° C, with a weight solvent ratio of 1: 5, for 40 minutes proved to be optimal for the maceration of aronia fruits. The total polyphenol content of the optimal extract was determined to be 5237.2 ± 40.7 mgGAEkg-1 and the antioxidant activity by TEAC to be 512.5 ± 5.04 gml-1. 24 aromatic active compounds were identified in the extract, with the largest percentage being monoterpenes and aldehydes. Furthermore, it was found that the extract did not show antimicrobial activity against the microorganisms used (Bacillus cereus, Escherichia coli and Candida glabrata). The obtained results confirm that aronia extracts are an important source of many biologically active compounds and can be used in food as a natural source of nutritionally and sensory valuable substances.

The Master' s thesis was made on Department of Post-Harvest Technology of Horticulture Faculty in Lednice. In the first chapter is defineded less common fruits and their healthy benefits. The main information about less common fruits and their processing are desribed in the other chapters. The experimental part include information of fresh fruits - honeysuckle, black chokeberry, hawthorn and their antioxidant activity. Antioxidant activity was detected by FRAP and DPPH. There is described the beverage production and the results of sensory analisis.

This diploma thesis deals with comparison of the properties of chokeberry spreads of different origins, composition and different production technologies. The theoretical part contains a brief description of the chokeberry – Aronia melanocarpa, an overview of the most important substances contained in the chokeberry and examples of the use of aronia, not only in the food industry. Furthermore, the legislative requirements for the production of spreads and the production technology itself are described. In this thesis is also described a new patented technology of spread production using HTD technology. Another part of the theoretical part is a literature review of the determination of anthocyanins in chokeberry by HPLC method. The experimental part describes the laboratory procedures used for determination of dry matter, carbohydrates by HPLC with ELSD detector, anthocyanin dyes, total phenolic compounds and antioxidant activity. Another part of the work was a questionnaire survey and sensory analysis of selected chokeberry spreads. The panel members prefered the Lowicz chokeberry spread, for which was determined 29,39% dry matter, 15,15 mg.g-1 anthocyanins, 9,20 mg.g-1 total phenolic compounds, 158,42 mg.g-1 fructose and 151,26 mg.g-1 glucose and the antioxidant activity was determined to be 5,94 mg.g-1.

This diploma thesis deals with chemical analysis of selected frozen, dried and lyophilized fruit, specifically Mirabelle de Nancy, Aronia Nero and blackcurrant varieties Gairn Ben and Ben Lomond. In the theoretical part taxonomy and botanical characteristics of selected fruit are given. Subsequently the utilization of fruit in food industry is described. In common the theoretical part focuses on lyophilisation and drying of fruit and raw food. Further in this part the methods of phenolic substances, anthocyanins, antioxidant capacity and finally ascorbic acid and carbohydrates value measurements are specified. In the experimental part the value were determined measurements of biologically active substances: total phenols, total anthocyanins, antioxidant capacity, ascorbic acid and carbohydrates. For all value measurements were compared the frozen, dried and lyophilised samples of every single fruit. Further, the every sort of fruit were compared to each other. Following the raw food preparaon a product of lyophilised fruit was made.

This diploma thesis deals with possibilities of using of aronia fruit pomace. The theoretical part is focused on botanical characteristics of aronia fruit, description of HPLC and anthocyanins dyes. The effects of various extraction condition on content of some polyphenolic compounds (gallic and vanilla acids, katechin and rutin) in aronia berry pomace are investigated in the experimental part. The mentioned compounds were detected with HPLC. Thanks to this method the content of carbohydrates was also detected. A quantity of anthocyanins dyes was determined by pH differential method.

Aronia (Aronia melanocarpa) is a berry fruit with distinctive sensory characteristics and health-promoting properties. Polyphenols are the main bioactive compounds found in aronia including natural pigments – anthocyanins. Bioactive compounds are usually obtained from natural materials by extraction, in this work, two methods of extraction were compared – maceration and PHWE. Based on the total phenolic content, maceration was chosen as a more suitable method and then was optimized with statistical model – Design of Experiment. Optimal conditions were set to temperature of 30 °C, extraction agent 50 % ethanol, solid-solvent ratio 10 g per 50 ml and time of extraction for 30 minutes. Extract obtained under these conditions was characterised by total phenolic content – 1441 ± 90 mg/100 g DW, total anthocyanin content 943 ± 8 mg/100 g DW and antioxidation activity by ABTS 24,78 ± 0,09 molTE/g. In total of 25 volatile compounds were indentified in the optimal extract with content > 0,5 %. Major part created aldehydes and esters, with the main compounds being benzaldehyde (32,25 %) and methyl hexanoate (21,37 %).

Diploma thesis deals with the characterization of chokeberry (Aronia melanocarpa) and saskatoon berry (Amelanchier alnifolia) fruits. The theoretical part focuses on the botanical classification, chemical composition, curative effects and the use of chokeberry and saskatoon berry in the food industry. Further, the attention is also devoted to a review of methods for the determination of important antioxidants, specialized on the determination of polyphenols, anthocyanins, ascorbic acid and total antioxidant activity. The experimental part of the work deals with the determination of selected parameters in different varieties of chokeberry and serviceberry, harvested in 2012 and 2013 using spectroscopic and chromatographic techniques with an emphasis on effect of solvent (50% ethanol, destilled water, DMSO). Specifically total content of polyphenols and anthocyanins, color characteristics using the CIE L*a*b* system and the ability of the sample to reduce the iron are determined using the UV-VIS-NIR spectroscopy. Further ascorbic acid concentration in individual extracts is quantified by High performance liquid chromatography coupled with a diode array detector and the total antioxidant activity is characterized by electron paramagnetic resonance involving •DPPH and ABTS•+ assays.

This thesis deals with the preparation of the combined alcoholic beverages based on wine and fruit juices. The fruit juices were obtained from the selected fruits as honeysuckle, mulberry, dogwood, rose hips, elderberry, buckthorn and aronia. Some chemical properties e. g. total fenolics, total anthocyanins, vitamin C and sacharides were determined for characterization of the mentioned juices. As well as chemical parameter of juices, the same chemical parameters were determined on wine. There were prepared three sets of combined beverages from wine and juices. The two best evaluated beverages were chosen on the basis of their sensory evaluation. In the end, the same chemical properties were determined in both particular juices and resulting beverages.