Diploma thesis deals with currant (Ribes L.) and substances which currants contain especially anthocyanin pigments, vitamin C and antioxidants. In theoretical part is described basic characteristic about plant, including varieties of currants. The following chapters include a list of active substances which the fruit contains and also the list of some possibilities of processing and utilization of currant especially in the food industry. Big attention is given to anthocyanins, their characteristics, utilization in the food industry, factors that affect their stability and especially methods of determination. In conclusion, the theoretical part describes importance and methods of determination of vitamin C and antioxidant capacity. Selected nutritional parameters were determined in fifteen known and in three unknown varieties of currants. Anthocyanins were measured spectrophotometrically and determined by HPLC in color samples. By pH differential method was evaluated a content of monomeric and polymeric pigments. By HPLC method were identified individual anthocyanin pigments contained in fruits. Also, content of ascorbic acid was determined by HPLC in all varieties. Antioxidant capacity of white currants measured by DPPH was compared.

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.

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Diploma thesis deals with determination of individual chemical parameters contained in modern varietes of gooseberries (Grossularia uva-crispa). The theoretical part is focused on the botanical characteristics of the plant, a description of selected varietes, chemical composition and food utilization fruits. The second half of the theoretical part is devoted to the characterization of selected nutritional parameters and methods for determination of total anthocyanins, phenolic compounds, vitamin C and antioxidant activity. Total of 17 varietes of gooseberries, which come from growers Vondráček and the Research and Breeding Institute of Pomology Holovousy Ltd. were analyzed in the experimental part. pH differential method was used to determination total monomeric anthocyanins. Total content of polyphenols were determined by using the Folin-Ciocalteu reagent. Next was determined content of vitamin C in all varieties by HPLC and was evaluated the total antioxidant aktivity using radical DPPH. In conclusion, individual varieties of gooseberries were compared by the contents of the determined chemical parameters.

The purpose of this thesis is to compare the contents anthocyans in different varieties of European elderberry (Sambucus nigra L.). It was also studied the relationship between the content anthocyans in selected samples of blue grape varieties (Vitis vinifera L.) and position of the track, where the grapes were grown. The theoretical part describes elderberries and grapes in terms of botanical, chemical, and in terms of their using in the food industry. The dominant part of this chapter is to describe anthocyans and possibilities for their determination in the elderberry and grapes. Emphasis has been placed on the pH-differential method and determination by high performance liquid chromatography. The experiments are divided into two parts. The aim of the first experimental part is comparison of the total anthocyanins content in fifteen varieties of elderberry. The performed analysis shows that in terms of anthocyanins content for cultivation of elderberry in the Czech Republic the most suitable varieties are Mammut, Samyl, Reis aus Vossloch and Haschberg. In the second part of the experiments were determined total anthocyanins content in nine varieties of blue grape grown in the Mikulov region. For determination were used HPLC and pH-differential methods, as well as in the first part. The highest content of pigments was found in varieties Alibernet and Neronet. The present study focused on the suitability of the location pointed to vineyard south to southeast orientation plantings. At the end of the experimental part is a comparison of both methods of determination. Method using high performance liquid chromatography to provide very accurate results compared to less demanding pH-differential method of determination. This is recommended only for tentative determination of anthocyanins content in real samples.