|
|
Simultaneous co-cultivation of selected strains of carotenogenic yeasts and autotrophic bacteria
Blažková, Jana ; Němcová, Andrea (referee) ; Szotkowski, Martin (advisor)
The submitted diploma thesis was focused on the study of co-cultivation of selected microorganisms, which were carotenogenic yeasts and cyanobacteria. The production of selected metabolites was compared in these co-cultivations. The main metabolites monitored were carotenoids, sterols, coenzyme Q10, chlorophylls and lipids. Furthermore, this work focused on the study and possibilities of optimizing the production of lipids and lipid substances in selected strains of carotenogenic yeasts and cyanobacterial species. The theoretical part is focused on the description of yeasts, especially carotenogenic yeasts, cyanobacteria and the chemical composition of the produced metabolites. Microorganisms such as yeast and cyanobacteria contain carotenoids, which are natural pigments and are classified as antioxidants. As antioxidants, they have significant biological effects, such as effects on human health. Coenzyme Q has a positive effect on the functioning of organs in the human body. Chlorophyll is widely used in the food industry as a green dye. Lipids produced by microorganisms contain a large amount of unsaturated fatty acids, which is currently used in cosmetics or pharmacy. The theoretical part also described the individual analytical methods by which the production of the monitored metabolites could be determined. The experimental part is focused on the production of carotenoids, sterols, coenzyme Q10 and chlorophyll, which were determined by HPLC, lipids and fatty acid profile were determined by GC. The determined metabolites are monitored in different types of co-culture partners (carotenogenic yeast and cyanobacteria) in media with different additions of macroelements (P, N and Mg). This was followed by a co-cultivation experiment using waste oils (frying and coffee oil) and a study of the effect of waste oils added to co-cultivations. Co-cultivation experiments confirmed the ability of carotenogenic yeasts and cyanobacteria to grow together. The best results were obtained with Rhodosporidium toruloides and Anabena torulosa, Rhodosporidium toruloides and Arthrospira maxima.
|
|
|
Application of physical and chemical stress factors in different stages of growth to autotrophic microorganisms
Sniegoňová, Pavlína ; Byrtusová, Dana (referee) ; Szotkowski, Martin (advisor)
Nowadays, the demand for metabolites produced by microalgae and cyanobacteria is still growing, due to their positive effects on the human body and health. These metabolites include mainly carotenoid pigments, that have antioxidant properties, which very attractive to consumers. These substances are mainly used in food supplements; however they are also used in the pharmaceutical industry. These substances include, for example, -carotene, but also chlorophylls, which are significantly involved in the photosynthesis process. Other important metabolites are lipids, which are part of cellular structures and serve a number of other functions. The theoretical part focuses on the description of algae and cyanobacteria and their cultivation. Furthermore, the influence of stress factors on the production of biomass and metabolites. Metabolites are then characterized in terms of properties and biochemical pathways leading to their production. Subsequently, there are mentioned evaluation techniques used to characterize the cultivated biomass. In the result part, the production properties are compared depending on the selected stress factors.
|
|
|
Cultivation of carotenogenic yeasts in the presence of biological stress induced by selected strains of autotrophic microalgae
Sikorová, Pavlína ; Byrtusová, Dana (referee) ; Szotkowski, Martin (advisor)
Presented Master’s thesis was focused on biological and nutrient stress in cultivations of green microalgae and carotenogenic yeasts. The focus of interest was production of biomass in different types of cultivation media, production of metabolites (mainly carotenoids and chlorophylls) and also production of lipids and lipophilic substances. All types of aplied stress was used to lead to an increased production of biomass and metabolites. The theoretical part deals with introduction of individual genera of carotenogenic yeast and green microalgae. The types of cultivation stress were also described. In addition, the analytic methods for qualitative and quantitative analysis are also introduced. The experimental part was focused on the study of biomass, carotenoids, chlorophylls, coenzym Q, sterols and lipids production. Biological stress was induced by cocultivation of microalgae and yeasts together.Nutrient stress meant adding macroelements or waste oils to the medium. Yeasts of interest were Rhodosporidium toruloides, Rhodotorula kratochvilovae and Sporobolomyces pararoseus. Microalgae was represented by Desmodesmus acutus, Desmodesmus armatus, Scenedesmus obliquus, Desmodesmus velitaris, Desmodesmus communis, Coccomyxa sp. Chlamydomonas reinhardtii and Chlorella minutissima. Generally the most successful multicultivator experiment was cocultivation with yeast R. kratochvilovae. In the case of cultivation on waste oils, the best producers of biomass and metabolites were co-cultivation experiments with the yeast R. toruloides. In microalgal experiments, it was found that nutritional stress in the form of glycerol added to the medium had an inhibitory effect on the growth and metabolism of microalgae.
|
|
|
Biological role of PHA cycle in bacterium Rhodospirillum rubrum
Šarköziová, Patrícia ; Obruča, Stanislav (referee) ; Slaninová, Eva (advisor)
The diploma thesis deals with the study of polyhydroxyalkanoates (PHAs) production and their protective effects during exposure of the bacterial strain Rhodospirillum rubrum to various stress factors. The theoretical part of this work is focused on the characterization of PHAs and used bacterial strain. In the first part of the experimental work carbon substrates for biomass growth and PHA production in different time intervals (24, 48, 72 and 96 hours) were investigated. Acetate, fructose, hexanoate and malate served as a carbon source. The second part of this work was focused on the selection of a suitable fluorescent probe for the bacterium Rhodospirillum rubrum (propidium iodide, SYTOXTM, fluorescein diacetate), which was used to determine the viability of bacterial cells using flow cytometry. This method was used to determine the viability of bacterial cells after their exposure to various stress factors (thermal stress, freezing and thawing, ethanol stress, osmotic stress, peroxide stress, pH stress and UV stress). Finally, the growth curve of bacteria Rhodospirillum rubrum was determined by measurement of the optical density.
|
|
| |
|
|
Anthocyanins in plant leaves: protective function and spectroscopic detection
Nikodymová, Michaela ; Albrechtová, Jana (advisor) ; Urban, Otmar (referee)
Plants have to cope with the change in the various environmental factors, the change of these factors means stress for plants. Stress factors can cause damage that lead to inhibition of growth and photosynthesis, resulting in the extreme cases in the death of the whole organism and negatively affect farm yields. Plants have to develop defensive mechanisms, including the accumulation of anthocyanins in leaves. The aim of the present review is to summarize the knowledge about the influence of stress factors on the accumulation of anthocyanins in leaves and about the function of anthocyanins in the protection. Anthocyanins most often act as antioxidants that react with ROS and inactivate them, they can also act as filters against UV radiation and as a protection against herbivores. Further, there are summarized the knowledge about spectral methods of detection of anthocyanins in leaves with emphasis on non-destructive detection methods. Spectral methods allow the analysis of anthocyanins based on the interaction of the leaf and its chemical components with the incident radiation. The most commonly used method is UV-VIS spectrophotometry. In order to study pigment change in leaves during ontogenetic development, non-destructive methods of pigment detection should be used. Suitable method can allow us...
|
|
|
Effect of stress factors on carotenoid production in isolated soil algae strains
Očadlíková, Terezie ; Němcová, Yvonne (advisor) ; Nedbalová, Linda (referee)
Microscopic green algae produce a number of beneficial substances. The commercially used ones include mainly pigments, especially secondary carotenoids. While primary carotenoids are part of the photosynthetic apparatus, secondary carotenoids are produced only under certain specific conditions (e.g. high exposure to light, nitrogen deficiency). Secondary carotenoids have antioxidant properties that protect the cell from adverse effects. The strains currently in commercial use and the strains that are tested for potential use come almost exclusively from algal collections, so this thesis focuses on strains isolated from nature. Two strains of aeroterrestrial green unicellular algae, which showed potential of producing carotenoids, were found and isolated. These strains were identified as Tetracystis pulchra (clade Dunaliellinia) and Tetracystis sp., a strain related to Tetracystis tetraspora SAG 98.80, belonging to the clade Stephanosphaerinia. The culture conditions for T. pulchra were subsequently optimized and then the culture was subjected to a series of experiments, examining the effect of stress factors on carotenoid formation and accumulation. Specifically, the effect of nitrogen starvation, light intensity, temperature and UVA radiation was tested. It has been shown that especially the light...
|
|
|
Transporters KT/HAK/KUP - role in plant development and response to environmental conditions
Doležalová, Barbora ; Tylová, Edita (advisor) ; Hála, Michal (referee)
Potassium is an essential element, which is important in many plant processes. It functions as a major osmotic and is involved in the regulation of turgor during cell growth or stomatal movements. It is also important for maintaining membrane potencial. In plants, potassium transporters from the KT/HAK/KUP family are involved in the transport of K+ . Some of them are important in the uptake of K+ from the enviroment (HAK5, KUP7), others in regulation of cell turgor (KUP2, KUP6, KUP8). In Arabidopsis thaliana, less characterized KT/HAK/KUP transporters include KUP5 and KUP9, which I studied in this diploma thesis. In this diploma thesis, I analyzed the growth phenotype of kup5 mutant plants. The results show that kup5 mutant plants are not more sensitive to K+ deficiency than wild-type plants, therefore KUP5 is probably not involved in the K+ uptake from the enviroment. Kup5 mutant plants were larger than wild-type plants, had larger root and hypocotyl cells as well as longer root meristematic zone. This growth phenotype suggests that KUP5 is involved in the regulation of cell growth, probably through turgor regulation. Using the pKUP5::KUP5-GFP construct, the KUP5 protein was localized in the ER, but this localization needs further verification. Using the pKUP5:GUS construct, KUP5 expression was...
|
|
|
Application of chemical and physical stresses in the late phase of growth to selected strains of microorganisms
Langer, Marek ; Holub, Jiří (referee) ; Szotkowski, Martin (advisor)
A wide spectrum of microorganisms is used in the biotechnological industry for production of meaningful metabolites; including carotenoids and chlorofyles with antioxidant effects, fatty acids, ubiquinone and ergosterol. Ways to increase yield of metabolites to maximum capacity are being researched to increase efficiency and economical sustainability in industry. One of the ways is the application of chemical stress factors on microorganisms as is described in this thesis. In the theoritical part certain microorganisms, their important intracellular metabolites and their metabolism are established. The last subchapter covers the usage of stress factors in industry. In the experimental part each microorganism was subjected to various concentrations of sodium chloride, cobalt(II) sulfate and iron(III) chloride. Significant increase of lipid production was registered after an application of sodium chloride on yeast strain Rhodosporium toruloides. An increase in production of torularhodin in Sporidiobolus pararoseus occured after application of iron salt. After an application of sodium chloride the growth of torularhodin in strains Cystofilobasidium macerans a Rhodosporidium toruloides was significant. Sodium chloride was also a suitable stress factor for lycopene formation in Rhodotorula mucilaginosa. The most meaningful stress factor of algae was cobalt(II) sulfate which increased metabolite production in Scenedesmus obliquus. Cyanobacteria Anabaena torulosa also attained a significant production in the presence of sodium chloride.
|
|
|
Study on PHA accumulation by cyanobacteria
Pacasová, Viktorie-Alexandra ; Slaninová, Eva (referee) ; Obruča, Stanislav (advisor)
This bachelor thesis was focused on studying the influence of selected stress factors on PHB production in strains of cyanobacteria Synechocystis sp. PCC 6803 and Synechocystis salina CCALA 192. Cyanobacterial stains were cultivated in multicultivator and as a stress factor an increased salt (sodium chloride) as well as a mixture of acetate and -butyrolactone was selected. The PHB content in cyanobacteria was determined by gas chromatography. In addition, the content and presence of pigments in cyanobacteria strains was determined by pigment extraction as well as using direct spectroscopy of whole cells. When cultivated with an increased salinity, the hypothesis of an increased PHB production was not confirmed most likely due to and overstressing the Synechocystis salina CCALA 192 cultures with increased salt content, constant illumination of multicultivator and by nitrogen limitation due to the used medium. When cultivated with the mixture of acetate and -butyrolactone the stains were analysed in the same way as in the cultivation with an increased salinity. In this case, the presence of 3-hydroxybutyrate and 4-hydroxybutyrate copolymer was determined in the stain cultivated with the mixture of acetate and -butyrolactone. During this cultivation, a positive effect of initial concentration of cells in the cyanobacterial cultures combined with continuous illumination and the type of nitrogen-limiting type of medium on the growth rate of selected stains was observed.
|
guest ::
