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Changes of enzyme activities in fruits during long-term storage
Ferdová, Jitka ; Melounová,, Jitka (referee) ; Márová, Ivana (advisor)
This study is focused on study of changes of enzyme and low-molecular weight antioxidants in different fruits during long-term storage. In theoretical part individual low-molecular weight antioxidants and enzymes are described. The main causes of fruit decay and some possibilities of fruit preservation and storage are summarized. As biological material some common fruits were chosen - green and red apples, peaches, plums and white grapes. The fruits were stored in laboratory, cellar, in refrigerator and in freezer. In freezing experiments some ways of fruit preparation and processing were tested and their influence on fruit antioxidant status was compared. Shortened storage experiment was applied on blueberries, cranberries, raspberries and strawberries too. In fruits some group parameters – total antioxidant status, dry mass content, ascorbate level, total flavonoids and total phenolics were analyzed spectrophotometrically. Individual flavonoids and phenolics were determined by RP-HPLC/UV-VIS and on-line LC/PDA/ESI-MS. Antioxidant enzyme activities (superoxide dismutase SOD, catalase CAT, polyphenol oxidase PPO and lipoxygenase LOX) were measured by spectrophotometry. The surface microscopy and cultivation of moulds from fruit surface were performed too. Influence of storage conditions on biological activities is dependent on fruit sort. Freezing is the most suitable procedure for long-term storage without significant changes of active substance content. Long-term storage in controlled temperature conditions and/or atmosphere is usable for fruits with longer storage period. In these fruits stabile levels of antioxidant enzymes are stored for relatively long time. Some of enzymes act synergistically. Enzyme activities differed according to storage phase; at the beginning mainly high SOD and LOX activities were observed. CAT and PPO are probably activated as defence systems in rippened and/or damaged fruits. Levels of total as well as individual low molecular weight antioxidants varied during storage in all sorts, generally, increased course with longer storage period can be observed.
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Determination of toxic and essential elements in plants
Filipčíková, Marcela ; Vespalcová, Milena (referee) ; Vitoulová, Eva (advisor)
The aim of diploma thesis is occurrence of toxic and essential elements in vegetables and fruit, especially in fruity baby food. The diploma thesis also dedicates processing of vegetables and fruit for production of baby food. Attention is direct to monitoring of baby food quality in the analytical aspects and also to legislative that is in this area. Samples for analysis are prepared using microwave mineralization and ICP-MS for detection. This is described in the experimental part of the diploma thesis.
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Elemental analysis of different currants varieties
Kovaříková, Tereza ; Divišová, Radka (referee) ; Diviš, Pavel (advisor)
This bachelor thesis deals with the elemental analysis of different varieties of red (Ribes rubrum), white (Ribes vulgare) and black currant (Ribes nigrum). The theoretical part contains botanical description of each variety of this small fruit, then description of analyzed elements and their function in human metabolism. Then there are described analytical methods suitable for elemental analysis in food. The experimental part is focused on the preparation of sample and its subsequent analysis by spectroscopic teqniques. All of the currant samples were given by Research and breeding institute of pomology Holovousy L.td. All the samples were mineralized by the wet ashing in concentrated HNO3 and analyzed by the ICP–OES teqnique. Final concentrations of each elements (Na, K, Ca, Mg, P, Fe, Zn, Cu, Mn) were stastistically compared by Tukey’s multiple comparation method and then have been compared with the results reported in literature.
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Elemental analysis of the different gooseberries varieties
Nývltová, Barbora ; Pořízka, Jaromír (referee) ; Diviš, Pavel (advisor)
This bachelor thesis describes and explores the elemental analysis of several new varieties of red and green gooseberries. The theoretical part deals with the history, taxonomy, cultivation and biological characteristics of gooseberry. The next part of the thesis is focus on the summary of nutritional parameters of the analyzed elements and it also describes the methods which characterize the analysis in the food use. The experimental part deals with the preparation of the sample, its subsequent decomposition by using wet way and of the actual analysis using the technique ICP-OES. The sample was provided by “Výzkumný a šlechtitelský ústav ovocnářský v Holovousích, s.r.o.”. The results of analyzed elements (Cu, Fe, Mg, Mn, P, Zn, Ca, K, Na) in the various varieties of gooseberry were further evaluated using statistical methods. These results were then compared with the available databases. The most promising in terms of the content of individual elements proved to be a variety of red gooseberry Rolonda and Jocheline, a variety of green gooseberry Invicta and Mucurines.
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Design of juicer
Michalicová, Anežka ; Rubínová, Dana (referee) ; Tomášková, Veronika (advisor)
This bachelor's thesis deals with the analysis and afterwards design of a juicer. First part is devoted to an overview of the history of juicers then it continues in technical analysis of the product and further analysis of juicers available on the current market. Following chapters focus on my specific design proposal and the solutions it delivers. The output of the thesis is textual analysis, mock-up model and a poster.
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Dzogchen and its philosophical aspect in Bon tradition
KLOZAR, Karel
The thesis deals with philosophical aspect of Dzhgchen, which is the core of the Yungdrung Bon traditon. It is very special spiritual tradition because of it's very special nondualistic view of man and universe. First part deals with the history and division of it's teachings and it's Dzogchen lineages. Next part focuses on explanation of differences in views of sutra, tantra and Dzogchen, mainly from the standpoint of the view of base, path, fruit, emptiness, clarity, conscioussness and mind and it's nature. Next part provides translation of the text Twelve little tantras and it's deep explanation. Last part, and most important one, focuses on philosophical examination of some key aspects of Dzogchen, mainly on it's view of autenticity of mindnature. This part also compares Pramenides's fragments with some key points of view of Buddhism and Dzogchen, which may lead to some unexpected conclusions about man's thinking and the problem of it's intentionality.
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Fruit and products of its processing and its importance for nutrition
JIRCOVÁ, Petra
The thesis is focused on fruits and products of its processing and its importance in nutrition. The theoretical part deals with the chemical composition of fruits in general are described and fruit products and their importance for human health, the important matter we deal mainly vitamins, fiber and antioxidants. The practical part consists of questionnaires on the subject and their evaluation. The aim was to find out what kind of relationship and knowledge of students and pupils of the fruit and eat it as often.
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Antioxidants in food and possibilities of nutrition application
DUBNOVÁ, Martina
The bachelor thesis concerns with the occurrence of antioxidants in foods, the possibilities of their applications in nutrition and population awareness on the topic antioxidants. The theoretical part describes the types of antioxidants, effects on human health and occurrence in foods and their recommended daily dosage. Further characterize free radicals and their negative effects on the organism. The practical part contains the research of the knowledge about antioxidants in the population in the form of a questionnaire. The results are analyzed and charted. The antioxidants are known by 82% of respondents. For the question ?What the antioxidants are used for? answered 54% of respondents correctly. In which foods the antioxidants are is known by 58% of respondents. The greatest awareness of antioxidants is in the group of workers, as well as students and in the group of retired respondents is the awareness of antioxidants slightest. Research shows that awareness of antioxidants which play a major role today in the prevention and treatment of lifestyle diseases and shows that more than half of respondent?s answers were inadequate.
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Cultivation Technology of Milk Thistle (Silybum Marianum)in Relation to the Product Quality and its Processing
GRAMANOVÁ, Hana
Silybum marianum has been a plant known for millenniums thanks to its pharmacological effects especially in fields of liver, gallbladder or even colon cancer treatment. A complex of effective components is called silymarin. Its amount and structure in milk thistle seeds are very important. That{\crq}s why there{\crq}s a tendency to develop methods which could increase silymarin quantity together with silymarin quality in this herb. This was also the aim of this thesis. One of the possibilities to level up the content of effective components in drugs is to bring this plant in stress. There were realized two ground-plot experiments. The stress agens was acetatonsalicylic acid (ASA) of different concentrations applicated on leaves of these plants, concretely in the concentrations of 10-5 mol.l-1, 10-4 mol.l-1, 10-3 mol.l-1. In the case of the application ASA concentration 10-3 mol.l-1 there was proved an effective action. The increase of effective components in seeds reached approximately 116,5 % ratio compared with control application of distilled water on the Silybum marianum leaves. The silymarin complex was determined by High Performance Liquid Chromatography. The preparation of the extract was practised in different ways {--} using ethyl alcohol extract and distilled water in combination with various temperatures of extracts storage. These methods were compared one another. As the best one has been turned out to be using 60% ethanol concentration for the duration of 96 hours in the storage temperature 20°C.
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Fruits and vegetables in food.
PROCHÁZKOVÁ, Michaela
This diploma thesis is focused on the theme fruit and vegetable in human´s nutrition. The theoretical part describes the nutrition in general, its parts and vegetable and fruit. Methodical part creates question-form on this theme with evaluation.
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