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Anthocyan pigments in selected fruits
Peprná, Tereza ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
This diploma thesis is concerned with determination anthocyanins dyes in elderberry (Sambucus nigra L.). In theoretical part there is described general characterization of the plant, its chemical composition, short view of elderberry breeding and possibilities of usage in food and medical industry. Bigger attention is paid to anthocyanins dyes. There is described their characterization, occurrence, factors that have an impact on their stability. Biosynhesis of the pigments and metabolism, benefit effects and their usage in food chemistry are then shortly sumarized. Methods of determination of anthocyanins are discused too. Next chapter deals with high performance liquid chromatography. At the end of theoretical part, there is sumarized findings of anthocyan dyes analysis by expert scientists in various matrix. In experimental part, total of 16 species of elderberry were analyzed. These species are from research and breeding institute of pomology in Holovousy. The dyes were identification and quantification by high performace liquid chromatography coupled with a diode array detector. Detection wavelenght was 520 nm. Gradient of mobile phase was optimilized because of shortening analyses time and resolution improvement. Four dyes were identified by HPLC: cyanidin-3-sambubioside, cyanidin-3-glukoside, cyanidin-3,5-diglukoside a cyanidin-3-sambubioside-5-glukoside. Total amount of anthocyanins ranged from 33627167,0 to 5525284,0 mAU•min-1. The most anthocyanins dyes were determined in Mammut species (33627167,0 mAU•min-1), the lowest amount was measured in Aurea species (5525284,0 mAU•min-1). The most abundant anthocyanin in all species of eldeberry fruit except Haschebrg and Aurea species was cyanidin-3-sambubioside. The concentrations of cynidin-3-glucoside in all of the berries were quantified using regression equation of calibration curve. Mammut species had the most amount of this anthocyan (0,486 mg•ml-1) and the lowest amount had Aurea species (0,033 mg•ml-1).
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Determination of anthocyanins in selected kind of fruit
Forejtarová, Darina ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
Contents of this diploma thesis was introduction of method determination of anthocyanin pigments by liquid chromatography. Anthocyanin pigments was determined in various cultivars of elderberry (Sambucus nigra L.) and in selected samples of red wine. In the first part of the theory is described elderberry, its species and chemical composition. Some possibilities of processing and utilization of elderberry in medicine are mentioned here too. The next part of the theory is aimed at chemical agents in wine, characteristics of anthocyanins and their utilization in food processing industry. The methods for determination of anthocyanin pigments with focus on HPLC are also mentioned there. The main objective of the experimental part of this thesis was comparison of content of anthocyanins in various cultivars of elderberry and in selected samples of red wine. In samples of red wine was observed not only cultivars´ influence, but also influence of the crop year on the content of anthocyanin pigments. The separation of the anthocyanin pigments by high-performance liquid chromatography with diode array detection (HPLC/DAD) was performed. The highest content of anthocyanin pigments in elderberry was determined in the cultivar Haschberg. In the case of red wine, the richest source of anthocyanins was the cultivar André 2009 – Rakvice. Higher content of anthocyanins was explicitly proved in young wines rather than in older wines.
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Extraction, separation and identification of anthocyans in skin of red cultivars of Vitis vinifera
Watzková, Jarmila ; Vespalcová, Milena (referee) ; Hrstka, Miroslav (advisor)
This diploma thesis deals with application of pressurized liquid extraction (PFE) on grape skins of Vitis vinifera cultivars Alibernet and Svatovavřinecké to gain extraction of anthocyanin pigments in the form of 3-monoglucosides. This thesis deals with comparison efficiency pressurized liquid extraction (PFE) for the range temperatures 40–120 °C and the Soxhlet extraction with four extraction solvents. The identification of the anthocyanin pigments by high-performance liquid chromatography with diode array detection (HPLC/DAD) based on Synergi C12 column separation (Phenomenex) was performed. The anthocyanin pigments were identified at wavelength 520 nm. The complete amount of anthocyanin pigments grape skins was depended on the extraction solvent and temperature in range 0,38–244,06 mg/g for cultivar Alibernet and 0,28–105,01 mg/g for cultivar Svatovavřinecké. The contents of anthocyanin pigments was determined in the samples of wine both cultivars in the range 3,83–2836,84 mg/l too. PFE followed by HPLC/DAD employing Synergi C12 column provides relatively fast, quantitative and reproducible determination of anthocyanins in grape skins and wines.
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Preparation and stability of core-shell type organic micro- and nanoparticles
Byrtusová, Dana ; Benešová, Pavla (referee) ; Márová, Ivana (advisor)
This bachelor thesis is focused on possibilities of encapsulation polyphenolic compounds in core-shell type organic micro- and nanoparticles. The theoretical part is aimed at characterization of polyphenolic compounds, their biological effects and their possibilities of encapsulation into various types of particles. The experimental part deals with the content of polyphenolic compounds, flavonoids and anthocyanins in guarana, ginseng ang goji. Extracts from these samples were packed into liposomes and polysaccharide particles. Encapsulation´s effectiveness was determined spectrophotometrically. The stability of particles was monitored for size and stability by dynamic light scattering. The particles were exposed to the model body fluids and model food.
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Honeysuckle Lonicera camtschatica - unconventional fruit of Czech republic
Rybníčková, Eva ; Šalplachta, Jan (referee) ; Vespalcová, Milena (advisor)
This work speaks about the possibilities of using fruits of the blue honeysuckle (Lonicera camtschatica) in the food industry. The first part describes the properties of this plant and methods of its cultivation. The second chapter deals with the chemical composition of the fruits and the importance of nutritionally valuable substances contained in them. The third chapter assesses the current appearance of the fruits in the world in the commercial point of view and the possibilities of processing the fruits into products. The last part deals with the methods of isolation and determination of important substances in the fruits, namely anthocyanins.
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Representative of small fruit - currant and its nutritional characteristics
Marková, Leona ; Vránová, Dana (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with representative of small fruit – currant (Ribes L.). Basic information about plant is described in theoretical part. Next there are described varieties, diseases and pests of currant. Attention is given also to production and consumption of these fruit in the Czech Republic. 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. In conclusion, the theoretical part describes the most common methods for the determination of anthocyanins. Main result of experimental part is comparison of the content of anthocyanin pigments in juices of red and black currant. Content of monomeric and polymeric pigments was evaluated depending on time and temperature of storage of currant juice and also after heating of this juice. pH differential method was used as the main method.
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Changes of antioxidants in selected fruits during long-term freezing
Štindlová, Jitka ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
In this bachelor thesis some low molecular weight antioxidants contained in strawberries, raspberries, blueberries and cranberries are described. In the theoretical part also general characteristics of these fruits are introduced. Experimental part was focused on analysis of the changes of selected antioxidant content in the fruits. These changes were monitored during storage in two different conditions – in refrigerator and in freezer. In refrigerator whole fruits were stored for 8 days. The experiment in the freezer was performed for 2 months and the fruits were stored in four different processed forms – as a whole fruit, whole fruit impregnated by sucrose solution, as a pulp and pulp mixed with sucrose. Antioxidant content in fruits was analyzed by HPLC and spectrophotometry. The highest total content of antioxidants was found in strawberries, while the lowest values were found in raspberries. During storage some part of original antioxidant content stayed conserved, the highest content was preserved in blueberries processed as a whole fruits and impregnated whole fruits.
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Dyes of red and white wine cultivars
Peprná, Tereza ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Theoretical part of this bachelor thesis contains informations about dyes of red and white grape species. At the beginning there is described component composition of grape berry. The biggest attention was paid to colour of red wine species. It deals with their common characterization, stabilization of their behaviour during production and storage wine. This work includes short recherche of their determination methods. Than there are mentioned colour of white wine cultivars. In another chapter there are described process of freeze drying otherwise lyophilization procedure. This method was used in experimental part while grape sample manufacturing. Grapes were immediately frozed on the dry ice after their separation. Skins were separated from pulp in nitrogen atmosphere and than these skins were lyophilizated.
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Fruit utilizing occasion of less knowing bushes
Mařáková, Veronika ; Vránová, Dana (referee) ; Vespalcová, Milena (advisor)
This bachelor thesis deals with cornelian cherry (Cornus mass). The beginning of the thesis treats with botanical characteristics of cornelian: description of the plant, its expansion, reproduction and location. There are described selected species, agricultural outplanting of the cornelian, its harvest and categorization to market kinds according to regulation of Ministry of Agriculture. Attention is given to actual substances contained in its fruits, especially vitamin C, which is presented in high amount there. This shrub includes many other important substances, like natural dyes - anthocyanins, minerals, organic acids, proteins, pectines, sugars, pulp and others. Fresh fruits are used mainly in food and cosmetic industry. At the end there are mentioned methods for determination of vitamin C by high performance liquid chromatography. The other possible ways how to determine vitamin C are titration method, spectroscopical method, polarographic method and gas chromatography.
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