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Characterization of plant-based component of selected foodstuffs using techniques of molecular biology and instrumental methods
Tomíšek, Martin ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The aim of this work was to compare authenticity analysis in selected food products with fruit component by using, instrumental and molekular methods. Particularly, the presence of blueberries in fruit–based foodstuffs was verified. The theoretical part is focused on the characterization, chemical composition and botanical classification of blueberries (European blueberry and Canadian blueberry). It also contains an overview of instrumental and molecular diagnostic methods that can be used for the analysis of these fruits. The experimental part focuses on the selection of a suitable method of DNA isolation, and primers for the detection of blueberries in commercial products. DNA analysis was performed by qPCR and HRM analysis. In the experimental part, DNA was isolated in sufficient quality for PCR and the presence of blueberries in foodstuffs was verified by qPCR. Using HRM analysis, we were able to differentiate between bilberry (Vaccinium myrtillus) and blueberry (Vaccinium corymbosum) in control samples and in some commercial products. Certain phenolic acids and some flavonoids specific for blueberries were detected by HPLC. The total content of polyphenols and flavonoids was determined by UV / VIS spectrophotometry.
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Changes in selected local fruits during freezing.
Matějková, Markéta ; Melounová, Jitka (referee) ; Márová, Ivana (advisor)
This diploma thesis was focused on study of low-molecular antioxidants present in various kinds of fruits, namely berries. In theoretical part detailed characterization of antioxidants studied in presented work and their biological effects are introduced. Further, principals of processing and storage of specified species of fruits are discussed. Changes observed during storage of specific fruits are described too. In practical part changes in content of selected antioxidants in berries were followed. As studied material strawberries, raspberries, blueberries, red and black currants were used. All kind of these fruits was stored in fridge for six months using several different kind of processing. Berries were stored as whole fruits, whole osmotically processed fruits by sucrose, raw pulp and sweetened pulp. At first, starting values of selected antioxidant parameters were measured in fresh fruits (ascorbate, total antioxidant activity, total phenolics, catechins and individual flavonoids). After freezing the same parameters were measured regularly in two month periods. As the most suitable method of fruit processing, with regard to antioxidant content, storage of the whole fruits or pulp can be recommended. Content of ascorbate decreased in all forms and species of the processed fruits during all the time of storage. Oppositely, the content of other studied antioxidants exhibited fluctuations or increasing trend. Sensory analysis was proved for the whole fruits and also for whole sweetened fruits.
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Identification of DNA from plant foods using molecular techniques
Papala, František ; Langová, Denisa (referee) ; Němcová, Andrea (advisor)
The aim of this bachelor thesis is the identification of plant DNA in a complex matrix using molecular techniques. The work first focuses on a search of literature sources concerned with molecular techniques of DNA identification. Next, it deals theoretically with methods of isolation and characterization of plant DNA. Specifically, we shall work with blueberry DNA. In the experimental part, DNA from four commercial products was isolated and subsequently subjected to PCR and HRM analysis.
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Identification of DNA from plant foods using molecular techniques
Papala, František ; Langová, Denisa (referee) ; Němcová, Andrea (advisor)
The aim of this bachelor thesis is the identification of plant DNA in a complex matrix using molecular techniques. The work first focuses on a search of literature sources concerned with molecular techniques of DNA identification. Next, it deals theoretically with methods of isolation and characterization of plant DNA. Specifically, we shall work with blueberry DNA. In the experimental part, DNA from four commercial products was isolated and subsequently subjected to PCR and HRM analysis.
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Characterization of plant-based component of selected foodstuffs using techniques of molecular biology and instrumental methods
Tomíšek, Martin ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The aim of this work was to compare authenticity analysis in selected food products with fruit component by using, instrumental and molekular methods. Particularly, the presence of blueberries in fruit–based foodstuffs was verified. The theoretical part is focused on the characterization, chemical composition and botanical classification of blueberries (European blueberry and Canadian blueberry). It also contains an overview of instrumental and molecular diagnostic methods that can be used for the analysis of these fruits. The experimental part focuses on the selection of a suitable method of DNA isolation, and primers for the detection of blueberries in commercial products. DNA analysis was performed by qPCR and HRM analysis. In the experimental part, DNA was isolated in sufficient quality for PCR and the presence of blueberries in foodstuffs was verified by qPCR. Using HRM analysis, we were able to differentiate between bilberry (Vaccinium myrtillus) and blueberry (Vaccinium corymbosum) in control samples and in some commercial products. Certain phenolic acids and some flavonoids specific for blueberries were detected by HPLC. The total content of polyphenols and flavonoids was determined by UV / VIS spectrophotometry.
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Changes in selected local fruits during freezing.
Matějková, Markéta ; Melounová, Jitka (referee) ; Márová, Ivana (advisor)
This diploma thesis was focused on study of low-molecular antioxidants present in various kinds of fruits, namely berries. In theoretical part detailed characterization of antioxidants studied in presented work and their biological effects are introduced. Further, principals of processing and storage of specified species of fruits are discussed. Changes observed during storage of specific fruits are described too. In practical part changes in content of selected antioxidants in berries were followed. As studied material strawberries, raspberries, blueberries, red and black currants were used. All kind of these fruits was stored in fridge for six months using several different kind of processing. Berries were stored as whole fruits, whole osmotically processed fruits by sucrose, raw pulp and sweetened pulp. At first, starting values of selected antioxidant parameters were measured in fresh fruits (ascorbate, total antioxidant activity, total phenolics, catechins and individual flavonoids). After freezing the same parameters were measured regularly in two month periods. As the most suitable method of fruit processing, with regard to antioxidant content, storage of the whole fruits or pulp can be recommended. Content of ascorbate decreased in all forms and species of the processed fruits during all the time of storage. Oppositely, the content of other studied antioxidants exhibited fluctuations or increasing trend. Sensory analysis was proved for the whole fruits and also for whole sweetened fruits.
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The nutritional importance of polyphenols in berries
MARTANOVÁ, Anna
People's nutrition is inseparable part of our lives. We could include substances, that we know are healtful, to our food. If we don't have enough of the substances, we can see negative effects on human organism. The substances are named micronutrients and vitamins. We could enrich a diet with substances that we think are healthy, but their deficit doesn't case pathological symptoms. Food which we put to this category is possible to name as function food. Function food contains substances which have positive effect on our health. One of the substances are polyphenols. This issue is very interesting for me, because polyphenols are compounds that are among others particulary found in berries, especially in blueberries. Blueberries are berries that are widespread throughout the world. One of the best sources of blueberries is also Sumava, where I come from and where blueberries are well connected. The first part of my thesis is about the functional foods and ingredients that make these foods Functional foods. Ordering: probiotics, prebiotics, synobiotiks, micronutrients, fytochemiks and polyphenols. Farther the first part deals with berries, specializing in blueberry and its properties and composition, which can have a positive impact on human health.In the second part there were two objectives of the work. The first aim of my study was to determine the diet, which includes foods that contain the optimum intake of polyphenols, equivalent to 120 ml of fetal native blueberries. Polyphenols are that part of blueberries, which make them so special. In the diet were preferentially embedded short dishes that have undergone heat treatment. Analyses of polyphenols in foods and beverages I got with the program GEOMED hospital Ceske Budejovice, Inc., Department of Clinical Pharmacology. Results polyphenol content were performed by HPLC. The content of polyphenols in native blueberries was laid as equal to 1 and the contents examined further product was then expressed as a multiple or ratio of the native blueberries. I take into account all these factors when drawing up the model menu. Another aim I have set is to map products in which the content of polyphenol is beneficial. There is a high number of products with blueberry flavour on the market. The content of blueberries, however, is often negligible. The surprising result was the polyphenol content in lemonade Toma, whose relative value ug / ml is 2.59 when compared with the native blueberry, which is placed as equal to 1. After the development work, in which I obtained information from the literature search, the sales network and the Department of Clinical Pharmacology, Hospital Ceske Budejovice, I would like to say that blueberries are an important source of polyphenols and that a diet which will include daily equivalent of receiving polyphenols, may not in any way differ from a regular rational diet. Not even cooking the dish precludes putting together this diet because blueberries are relatively stable against temperature changes. Inclusion of such a diet in the catering equipment could bring a positive impact in the future, especially for older people by improving memory function and balance.
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Fytochemical potencial of polyfenols contain in berries
KRUMPHANZLOVÁ, Iva
This thesis sums up findings on polyphenols and their positive influence on human health. In these fytochemicals, unlike in micronutrients, recommended daily amount cannot be estimated. Micronutrient deficiency in food can cause deficiency symptoms, while in polyphenol deficiency, the deficiency does not occur. When they are present in sufficient amount in food, it is considered functional food, which is important for civilization illnesses prevention. At the beginning of the theoretical part, the polyphenol classification from pharmacological and chemical point of view is represented. On the basis of this classification important role of antioxidants and flavonoids is described. Special attention is being paid to resveratrol, which is populardue to its well known "French paradox". The following part considers the polyphenol influence on human health. The way in which polyphenols protect our body from certain diseases is explained in detail. Most of the health benefits are supported by studies conducted on animals. These studies are also mentioned and described in this paper. In the theoretical part the process of absorption and the polyphenols safety for human body is also explained. Polyphenol sources are listed in the last subchapter. The work is mainly aimed at blueberry fruits (Vaccinium myrtillus) and vine grapes (Vitis vinifera). Other berries are briefly mentioned as well, such as cranberries, raspberries, blackberries and currant. The goal of this work is to create a diet that would provide a functional daily amount of polyphenols. This amount can be compared to 120 ml of native blueberries. Only products, consumable without cooking, are used in this diet. The second goal is to chart, which food products are adequate source of polyphenols. On the basis of these goals, research inquiries were defined. Research inquiry No. 1: What amount of polyphenols is contained in berries, especially blueberries. Research inquiry No. 2: Which food products (without cooking) are ideal to be included in diet, to provide adequate daily amount of polyphenols. To asses polyphenol content in blueberries, analysis of polyphenol content acquired through GEOMED program from Nemocnice České Budějovice a.s., department of clinical pharmacology, was used. Assessments were made using the HPLC method (high performance liquid chromatography) in cooperation with the biological centre AV ČR in České Budějovice. Thanks to this analysis, the first inquiry can be answered. An interesting phenomenon is discovered, that frozen blueberries have higher polyphenol content then cooled ones. Malvidin (malvidin-3-6"-acetoyl glycoside) was chosen as priority anthocyan since it is most represented in the blueberry. Remaining information about polyphenol content in certain food products were drawn on Joseph Maroon´s book, MD, FACS (2010). The practical part involves a diet for 14 days, which meets the given requirements. The results clearly show that it is possible to create a diet rich in polyphenols. A list of blueberry products accessible to everyone is included. Blueberry dairy products, jams, beverages, fruit salads and fruit pyre have been analysed. The list shows which product contains the most polyphenols. The required amount can be achieved by the proper combination of given products. The ideal one proved to be 200 ml of red wine and one blueberry dairy product (with the malvidin value higher than 64). Findings in this paper will serve to promote polyphenol awareness and itseffects. This diet can be used in nursing homes, where their positive influence on equilibrium can be applied. It can also be used in spas and other alimentation related facilities.
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