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Production of carotenoi by yeasts of the genus Cystofilobasidium
Vavrysová, Alena ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
Carotenoids are important industrial pigments present practically in all living organisms. The aim of presented work is the study of regulation of carotenoid production in yeasts of the genus Cystofilobasidium in presence of exogenous stress factors. Growth curve of C. capitatum exhibited typical two-stage course with prolonged stationary phase similar to other carotenogenic yeasts. Maximal production of biomass and beta-carotene occurred in 103rd hour. Applied stress factors (2-5% NACl, 2-5 mM H2O2, 0,01-1 mM Se(IV), 0,1-5 mM Cr(III)) exhibited no significant influence on biomass production, which reached on average 8-9 g/l. Positive effect was observed in presence of 5mM Cr where 10 g/L of biomass was produced. Beta-carotene formation was positively influenced by many applied stress factors, the highest yield (695 g/g) was reached in presence of 0,1 mM Se(IV). No simultaneous regulation of ergosterol and carotenes was observed in Cystofilobasidium cells. Production properties of yeast strain C. capitatum CCY 10-1-1 wee compared with those of other carotenogenic yeasts of the genes Rhodotorula and Sporobolomyces. C. capitatum produced similar biomass yield as Rhodotorula sp. in presence of salt. Production of beta-carotene by C. capitatum was slightly higher than in Rhodotorula glutinis, but lower than in Sporobolomyces strains which exhibited substantially lower biomass production. Karyotype of C. capitatum is relatively different when compared with karyotype of other carotenogenic yeasts. Based on summary of our results in seems that yeasts C. capitatum exhibit similar physiological as well as production properties as some Rhodotorula strains. Thus, yeasts of the genus Cystofilobasidium could be potentially used to industrial production of carotenoid pigments as well as yeast biomass rich in carotenoids and some biogenic elements.
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Analysis of czech garlic varieties
Fähnrichová, Nikola ; Vespalcová, Milena (referee) ; Diviš, Pavel (advisor)
This master thesis deals with analysis of Czech garlic varieties in comparison with two varieties from abroad. Alliin and carbohydrates were determined by high performance liquid chromatography with diode-array detector or evaporative light scattering detector. Crude proteins were calculated from total content of nitrogen that was determinated by Kjeldahl method. Elementary analysis was performed by inductively coupled plasma optical emission spectrometry. In theoretical part of this thesis is describes botanical characterization and cultivation of garlic, chemical composition of garlic, especially groups of substances which were analysed in this thesis. Principle of used methods is described too. The experimental part of this work deals with sample and calibration solution preparation and process of analysis. Obtained results from analysed substances are summarized in the tables, discussed and compared with results of analysis of other authors. Between Czech and Spanish/Chinese garlic are slight differences. Garlics contain 24,66 g/kg dry weight of alliin. Content of crude proteins in Czech garlic is comparable to Chinese garlic but the Spanish garlic has just half of amount crude proteins. Elementary analysis also includes significant differences. Czech varieties contain higher amount of phosphorus, iron and zinc. On the contrary, content of potassium in foreign garlic is higher than in Czech Republic and the analysed amount is 15 g/kg dry weight.
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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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Assessment of rutin in elderberries
Kaňová, Kateřina ; Hrstka, Miroslav (referee) ; Vítová, Eva (advisor)
This work is focused on determination of the concentration of rutin in the fruits of elderberry (Sambucus nigra L.). The theoretical part provides an overview of the properties, occurrence and use of elderberry in natural healing, medicine and food industry. Furthermore, important substances contained in elderberry, especially flavonoids, including rutin, are mentioned. Properties, biological effects and the possibility of determination of rutin are briefly described. In the experimental part the optimization and validation of the method of high performance liquid chromatography (HPLC), which is used for identification and quantification of rutin in fruits of 18 elderberry species, was performed. The pressurized hot water extraction was used for the preparation and solid phase extraction (SPE) for purification of the sample. The largest amount of rutin was found in a variety of elderberry Albida, 6,70 mg per 1 g of dry matter. High concentrations of rutin included varieties Haschberg, Sambu, Pregarten, Sambo and Sampo. On the other hand, the lowest concentration was found in variety Aurea, 1,24 mg.g-1. Finally, rutin content in elderberries was compared with the content of rutin in elder leaves and branches andwith significant sources of rutin – buckwheat and rue.
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Adaptogens in the Shizandra chinensis plant
Pospíchalová, Lucie ; Půčková, Helena (referee) ; Kotlík, Josef (advisor)
This diploma thesis deals with plant adaptogens (bioactive substances) in the plant Schisandra chinensis. The theoretical part is focused on characterization of the Schisandra genus, characterization of the Schisandra chinensis as a plant, its properties, occurrence and growing possibilities in the climate zone. Furthermore, The effects of these adaptogens on the organism and the prediction of possible use in food supplements are described. The experimental part deals with the extraction of fruits and leaves from plant Schisandra chinensis. Further, chlorophyll a, chlorophyll b in the leaves extract was determined by UV – VIS spectrophotometry, whereby the optimal amount 3:1 of chlorophyll was confirmed for the plants growing in optimal conditions. Finally, the concentration of the adaptogen schisandrin A in the dried fruits was from different kind of extraction measured by HPLC. In all fruits, schisandrin A was confirmed, but the amount is different in each sample.
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Study of geographical authenticity of Moravian white wines
Horáková, Kristýna ; Křikala, Jakub (referee) ; Diviš, Pavel (advisor)
The aim of this bachelor thesis was to verify geographical autenticity of Moravian white wines based on elemental analysis. This data were completed with the analysis of organic acids, fenolic compounds and atioxidants in wines. There were used two spektrometric methods for the elemental analysis (ICP-MS and ICP-OES). The concentration of organic acids was mesured by Ion chromatography. To determine the concentration of phenolic compounds in wines there was used the high performance liquid chromatography (HPLC-DAD), the content of antioxidants and the total content of phenols was measured on spectrophotometer. In total there were 33 samples of wine from 4 Moravian subregions. For the purpose of determination the samples in groups the dataset was firstly corrected by Grubbs test for remote results. From those data the box plots were created which represents the minimal, maximal and mean concentrations of each measured component. Furthermore the analysis of variance was applied, which picked up 12 statisticly valuable parameters from the whole 47. By appliyng the multidimensional statistical methods (Pearson correlation analysis (PCA) and discriminant analysis (DA)) were compiled mathematical models for the division of Moravian wines according to geographical origin. The success rate of the discrimination test was 96,97%. The cross-validation test showed an 81,82% success rate for classifying unknown samples.
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Study of the authenticity of chocolate with different content of cocoa solids
Vanduchová, Petra ; Dvořák, Miloš (referee) ; Diviš, Pavel (advisor)
This master's thesis deals with authenticity of chocolate with different content of cocoa solids. The theoretical part describes the production of chocolate products and the issue of food authenticity. Experimental part of this thesis is focused on the determination of total cocoa solids in the selected samples. Different samples of chocolate containing 50–90 % of cocoa were grated to fine particles, that were subjected to extraction without previous chemical treatment. The methylxanthines theobromine and caffeine were detected by HPLC to determine the content of fat–free cocoa solids. Fat–free cocoa solids content were found in the range 19,7–43,1 g/100 g of dry matter and the content of total fat was determined by the gravimetric method and was found in the range 30,9–55,4 g/100 g. The results of this thesis prove that, the producers meet the legislative requirements and the declared values are corectly declared on the wrappers of the product.
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Characterization of yeast and algae metabolites by instrumental techniques
Kurowska, Klára ; Márová, Ivana (referee) ; Němcová, Andrea (advisor)
The presented diploma thesis deals with the analysis and production of selected microbial metabolites of the yeast Rhodotorula kratochvilovae in comparison to various species of microalgae. The theoretical part summarizes the knowledge about the conditions for optimal growth and production of secondary metabolites. Analytical methods, by which metabolites were quantified and evaluated, were also described. In the experimental part of this thesis, the amount of accumulated biomass, exoglycolipids, intracellular lipids, phycobiliproteins and carotenoids according to various nutrient sources in the culture medium was studied. Specifically, the yields of these metabolites were investigated in the utilization of various sources of nitrogen (yeast extract, urea, ammonium sulfate, ammonium chloride and potassium nitrate), carbon (glucose, mannose, xylose, glycerol and lactose) and at variable C / N ratios (20; 40; 70; 100 and 120: 1) ideally selected sources of observed nutrients in partial experiments. The last part of the experiment was focused on comparison of the analysis of metabolites of autotrophic algae (chlorophylls, phycobiliproteins and lipids).
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Selected bioengineering characteristics of lactic acid bacteria
Šťásková, Lucie ; Vítová, Eva (referee) ; Babák, Libor (advisor)
The diploma thesis deals with the growth of biomass and production of selected metabolit–lactic acid by thermophilic bacteria Bacillus coagulans. The resulting selected metabolite was determined by HPLC method. Cultivations of this genus were performed on synthetic media, where the influence of carbohydrate used as carbon source was tested. Lactose was more suitable fot growth of biomass and glucose for production of lactic acid. On natural whey media the influence of different conditions were tested. The highest yields of biomass and production of lactic acid were observed on enriched whey medium. The last part deals with comparing the production of biomass and metabolites, depending on the volume of media. There were compared selected bioengineering characteristics of all cultivations.
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Development and optimization of methods for detection of selected fruit species in foodstuffs
Šlosárová, Katarína ; Wikarská, Monika (referee) ; Fialová, Lenka (advisor)
Various types of adulteration of food products are becoming more frequent in the food industry than ever. That is no different for fruit products. This bachelor thesis deals with the detection of mango in fruit purées for infants through the use of qPCR and HPLC in three selected commercial products and their prepared replicas. Within the framework of molecular biology, different primers specific for mango were tested. Several primers, which were the most suitable for the demonstration of mango in fruit purées, were selected based on the course of the qPCR reaction, the size of the amplified product, specificity, and sensitivity. Using these primers, the presence of mango was proven in all six analysed samples. Regarding the instrumental part of the work, a rapid and simple method of extraction of phenolic compounds for their analysis by HPLC was tested, which has been previously successfully used on another plant matrix. This method was proved to be unsuitable for the extraction of phenolic compounds from fruit purées for the purpose of their authenticity verification using HPLC [1].
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