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Optimization of calcium chloride concentration for removal of polysaccharide contamination during plant DNA isolation
Frnčová, Ekaterina ; Šlosárová, Katarína (referee) ; Fialová, Lenka (advisor)
The greatest difficulty in isolating DNA is the presence of contaminants that cause side effects. Polysaccharides are the most common contaminants in fruits. They can distort the results in spectrophotometric determination of purity or act as inhibitors in PCR analysis together with other substances (for example, proteins or phenolic substances). The aim of this work was to investigate the influence of different concentrations of calcium chloride on the process of DNA isolation. In the experimental part, DNA from the apple was isolated using different concentrations of calcium chloride. The isolation was carried out four times, and each time the sample was adjusted in different ways. It was found that the isolation method used works only with a sample that has been lyophilized. Isolation of DNA from fresh fruit provided very low yields. Probably, this was due to the large water content in the sample, and the proportion of the solid component was smaller. Subsequently, PCR analysis and electrophoresis were performed to determine the amplifiability of the isolated DNA. Two sets of primers with different specificity were used for this analysis. Amplifiability was confirmed only when using primers specific to apple DNA when using 100 mM solution of CaCl2. Other samples have been amplifiable using both types of primers. Probably, samples isolated using a 100 mM solution of CaCl2 had a larger amount of inhibitors that do not affect all PCR reactions equally, which may also indicate a small effectiveness of this amount of CaCl2.
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Development of cereal products for specifc nutrition with addition of fruits and vegetables
Růžičková, Magdalena ; Kubalová, Michaela (referee) ; Bendová, Agáta (advisor)
This bachelor thesis focuses on developing gluten-free cereal products for special nutrition. The main focus is on increasing the concentration of phenolic compounds and antioxidants in cereals by adding fruit and vegetable components. The theoretical part includes findings from professional literature on cereals, gluten-free cereals and their chemical composition. A chapter devoted to celiac disease and gluten-free diet was also included. Furthermore, the theoretical part focuses on possible methods of enrichment and also on selected fruits and vegetables used in the experimental part. In the experimental part, five samples of gluten-free cereals were analysed, namely black, red, brown and white rice and corn. The concentration of flavonoids, polyphenols, antioxidants, carbohydrates, proteins, -carotenes, anthocyanins, gluten, -glucans, fatty acids and lipophilic vitamins was determined in the cereal samples. Selected samples were also tested for antimicrobial activity. The black rice sample showed the best results in the majority of the measurements. Selected samples of eight types of fruit (cranberry, raspberry, strawberry, blueberry, blackcurrant, mango, banana, kiwi) and four types of vegetables (broccoli, carrot, green pea, beetroot) were also analysed. The concentration of flavonoids, polyphenols, antioxidants, carotenes, anthocyanins, ascorbic acid and lipophilic vitamins was determined in these samples. Antimicrobial tests were performed on selected fruit and vegetable samples Among the fruit samples, the best results in the majority of measurements were in blueberry and blackcurrant samples. Among the vegetable samples, the best results were obtained from the beetroot sample. From the best cereal, fruit and vegetable samples were created porridges as a final product. In these samples, the concentration of polyphenols and antioxidants was determined. The highest concentration of both compounds was found in the porridge with black rice and blueberry.
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Possibilities of processing the fruit of lesser-known fruit tree species
Vachta, Jonáš ; Hudečková, Helena (referee) ; Mikulíková, Renata (advisor)
This diploma thesis deals with the possibilities of using the fruits of common quince (Cydonia oblonga), common medlar (Mespillus germanica) and flowering quince (Chaenomeles speciosa) for food purposes, specifically for the production of jellies and jams. The goal was to create a product that would capture the character of the fruit used, preserve its beneficial properties, such as aromas and the content of bioactive substances, and at the same time be pleasant for consumers. A total of three types of products were prepared, namely gelatin jelly, agar jelly and jam for each type of fruit used. The product samples were subjected to sensory analyses, the aim of which was to determine the optimal addition of sugar to the product, to determine the overall consumer acceptability of the individual samples, and in the case of jelly, also to compare the sensory properties of the gelatin and agar variants. For chemical analyses, model samples were prepared, the composition corresponding to the best sensorially evaluated samples from each type of product. The total content of polyphenols, the total content of flavonoids, the content of vitamin C, the content of lipophilic pigments, ubiquinone and phytosterols and the profile of volatile compounds in individual samples were studied. The analysis results showed that the jams, as heat-processed products, generally retained a greater amount of bioactive substances compared to the jelly samples, and in certain cases even a greater amount than the fruit samples. The jelly samples, on the other hand, retained a greater amount of the original fruit aroma.
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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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Stability and properties of combined beverages and fruit concentrates
Klatová, Kamila ; Vítová, Eva (referee) ; Vespalcová, Milena (advisor)
This diploma thesis deals with the stability and basic properties of combined beverages and fruit concentrates. The theoretical part describes the production and use of fruit concentrates. Furthermore, the work deals with anthocyanic pigments and phenolic substances. The principle and instrumentation of liquid chromatography and electron paramagnetic resonance were described. In the next subchapter, the methods of determination of total anthocyanins and phenolic substances were described. The experimental part of the thesis described the determination of soluble solids, viscosity and antioxidant activity. The total content of phenolic compounds were determined by the Folin-Ciocalteua method and the total anthocyanins were determined by the pH-differential method. In the samples were determined cyanidine-3-glucoside and cyanidin-3-galactoside by liquid chromatography.
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Influence of matrix type on the authentication of foodstuffs containing fruits
Kopková, Pavlína ; Strečanská, Paulína (referee) ; Fialová, Lenka (advisor)
Certain types of food, mainly the more expensive ones, are often adulterated to reduce their manufacturing price. However, this reduces their quality and can also have a negative impact on the health of the consumer. Children's fruit products are also targeted by fraudulent producers, where the declared fruit is most often replaced by a cheaper version. This work focuses on the detection of adulterated foods using various analytical methods, in particular PCR. The theoretical part focuses on the issue of food adulteration, the analytical methods used for detecting adulteration, and also on mango and banana which are determined in this work. The aim of this thesis was to determine what effect the type of matrix has on the determination of fruit components in food by PCR. Three types of matrix were used for this purpose - fruit puree, smoothie, and bars. An important task was to optimize the DNA isolation to achieve adequate purity and concentration of DNA. Then, the amplifiability of the obtained DNA was verified. The DNA isolates were then analyzed by multiplex PCR with primers specific for mango and banana. The results were verified by agarose gel electrophoresis. Subsequently, it was possible to determine that the fruit component in bars and fresh smoothies was the most easily analyzed by PCR and, on the contrary, the determination was problematic for puree. The instrumental part was focused on the determination of phenolic compounds in the products by HPLC. For this purpose, optimization of the extraction of phenolic compounds was necessary. This method was able to detect the presence of mangoes in all samples.
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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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Detection of selected fruit species in plant-based foodstuffs through instrumental analysis and methods of molecular biology
Ondruch, Petr ; Langová, Denisa (referee) ; Fialová, Lenka (advisor)
Food is often subject to adulteration, including fruit products containing strawberries. This work deals with the detection of strawberries in model and real fruit products, so that possible falsification can be detected. The aim of the work was the preparation of model and real fruit products, their analysis using selected instrumental and molecular-biological methods and mutual comparison of the results of these methods. Model mixtures of fruit products were prepared and commercial ones were purchased. The content of polyphenols and flavonoids was determined by UV-VIS spectrophotometry, which were characterized in more detail by HPLC. DNA was isolated from the fruit purees, suitable primers confirmed the amplifiability and formation of a specific product for strawberry, and this product was verified by electrophoretic control. In the instrumental part, certain substances were detected by extraction from model and commercial mixtures and the HPLC method, and the amount of selected substances was determined. The lowest amount of strawberry DNA that could be detected by selected primers in the PCR method was 0.7 ng /µl, in commercial mixtures this DNA could not be detected. In the HPLC method, the strawberry was detected in all samples by focusing on a particular fingerprint and the amount of pelargonidin-3-glucoside in the samples. The instrumental method can be considered more suitable in this case.
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Elemental analysis of different kinds of small fruit
Štursa, Václav ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This diploma thesis deals with the elemental analysis of soft fruit species such as currants and gooseberries. The theoretical part contains botanical description of both species, then description of nutritional properties of the individual analyzed elements and ends with a list of analytical methods suitable for elemental analysis in the food science and with a description of preparation. The experimental part deals with sample preparation and its analysis afterwards with spectroscopic techniques. Samples of different varieties of gooseberries, black, red and white currant from “Výzkumný a šlechtitelský ústav ovocnářský v Holovousích, s.r.o.” have been used for the analysis. Samples were mineralized in concentrated HNO3 and analyzed by ICP-OES technique. Difference in resultant concentrations of the analyzed elements (Ca, Cu, Fe, K, Mg, Mn, Na, P, Zn) between individual varieties were statistically compared by Tukey’s multiple comparison method and results achieved have been as well compared with the results reported in available literature.
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