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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.
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Metabolic adaptation of selected microalgal strains on various nitrogen sources
Kodajek, Matěj ; Šimanský, Samuel (referee) ; Szotkowski, Martin (advisor)
Microalgae and cyanobacteria are photosynthetic organisms that, together with other microorganisms (yeast, bacteria), are used in industry, because they produce a wide range of interesting organic substances. This thesis deals with the metabolic adaptation of microalgae Scenedesmus obliquus, Scenedesmus acutus, Scenedesmus dimorphus, Chlamydomonas reinhardtii, Coccomyxa sp. and cyanobacteria Synechococcus nidulans, Arthrospira maxima, Limnospira maxima, Anabaena torulosa, which were cultivated on various nitrogen sources. These strains are descibed in the theoretical part including the metabolites and their applications in industry. The experimental part describes all chemicals, aids, devices and methods used for cutivation and analysis of microorganisms. The aim of the study was to compare and find out which nitrogen source in the BBM and SPIRULINA medium is the most suitable for a particular strain in terms of production of total biomass and composition of individual metabolites. Sodium nitrate, ammonium sulfate, glycine, urea and whey protein were used as nitrogen sources. The content and composition of lipids in the biomass was determined by gas chromatography. The content of ubiquinone, carotenoids and chlorophylls was determined by liquid chromatography.
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Optimization of extraction of metabolites produced by selected strains of microalgae and carotenogenic yeast.
Obračaj, Jan ; Holub, Jiří (referee) ; Szotkowski, Martin (advisor)
This bachelor thesis is focused on the production of microbial biomass using selected strains of cyanobacteria and carotenogenic yeasts. Subsequent preparation of extracts and study of their stability under different temperature conditions with the addition of the antioxidant tocopherol. In the experiment, 2 series of extracts with hexane and ethanol were prepared. The theoretical part of the work describes the studied metabolites carotenoids, chlorophylls, ubiquinone, ergosterol and microbial lipids. Furthermore, the used strains of cyanobacteria and carotenogenic yeasts are described here. Finally, methods for extraction and analysis of metabolites are described. The experimental part describes the used cultivation techniques, preparation of microbial extracts and used analytical methods. The results part of the work then contains a summary of the results of long-term stability tests of extracts. The results of the work clearly confirm the temperature dependence of the stability of individual metabolites. This phenomenon was most evident in chlorophyll and carotenoid pigments. Hexane appears to be the best solvent in terms of the stability of the substances used. The results of this work provide important information in terms of the economics of storage of these valuable substances usable in the food, pharmaceutical or feed industries.
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Controlled production of lipids and lipidic substances by selected yeasts and microalgae
Szotkowski, Martin ; Kráčmar, Stanislav (referee) ; Huelva, Ines Garbayo Nores, University (referee) ; Márová, Ivana (advisor)
Karotenoidy jsou přírodní pigmenty vyskytující se v mikroorganismech jako jsou řasy, kvasinky a sinice. Představují nejrozšířenější skupinu antioxidantů s významným biologickým účinkem. V současnosti vzrůstá zájem o karotenoidy vzhledem k jejich příznivým vlivům na lidské zdraví. Chlorofyly jsou zelená fotosyntetická barviva, která nacházejí uplatnění v potravinářství jako intenzivní zelená barviva. Koenzym Q je znám svým pozitivním vlivem pro správnou funkci řady orgánů v lidském těle. Ergosterol je nedílnou součástí membrán kvasinek a hub. Je to provitamin D2, který je důležitou součástí imunitního systému. Mikrobiální lipidy, nebo také ‚‚Single cell oils‘‘ jsou charakteristické vysokým obsahem zdraví prospěšných nenasycených mastných kyselin, které lze využít ve farmacii či kosmetice. Mikrobiální lipidy jsou dále studovány jako alternativa pro výrobu biopaliv. Dizertační práce byla zaměřena na studium a možnosti optimalizace produkce lipidů a lipidických látek vybranými kmeny karotenogenních kvasinek, mikrořas a sinic. V rámci práce byly testované kvasinky rodu Rhodotorula, Rhodosporidium, Cystofilobasidium a Sporidiobolus podrobené kultivacím na sérií médií s různými C/N poměry v rozsahu 13 až 100, obsahujících upravené odpadní substráty z potravinářského průmyslu. Vybrané kmeny byly poté kultivovány v bioreaktorech v médiu obsahujícím kombinaci odpadních substrátů. Kultivace mikrořas rodu Desmodesmus, Scenedesmus, Chlorella, Coccomyxa, Chlamydomonas, Botryococcus se zabývaly optimalizací jednotlivých komponent média a aplikací různých stresů s cílem navýšení produkce studovaných metabolitů. V rámci experimentů s extrémofilní mikrořasou Coccomyxa byly provedeny pilotní velkoobjemové kultivace v otevřených nádržích. V závěrečné části byl provedeny pilotní screeningové a velkoobjemové bioreaktorové experimenty zaměřené na možnosti kokultivace karotenogenních kvasinek a mikrořas. Testované kmeny kvasinek byly s rozdílnou úspěšností schopny utilizovat média obsahující hydrolyzované odpadní substráty. Nejlepším kmenem byl Sporidiobolus pararoseus, který na médiích dosahoval nejvyšších produkcí biomasy i sledovaných metabolitů. Z testovaných odpadních substrátů byla nejlepší kombinace odpadního fritovacího oleje a hydrolyzátu kávové sedliny. Úspěšná optimalizace složení hlavních komponent minerálního média vedla k zvýšené produkci studovaných metabolitů. Největší vliv měl optimální poměr P/N a aplikace oxidačního stresu. Nejlepších výsledků dosáhly mikrořasy rodu Desmodesmus a Scenedesmus. Velkoobjemové kultivace Coccomyxy onubensis potvrdily rezistenci kultury proti kontaminaci vnějšími vlivy a schopnost růstu za vysoké teploty a intenzity světelného záření. Kokultivační experimenty potvrdily schopnost symbiotického růstu kvasinek a mikrořas. Nejlepších výsledků dosahovaly všechny testované kvasinky s mikrořasami rodu Demsodesmus a Scenedesmus a v menší míře i rodu Coccomyxa.
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Biological effects of complex extracts from yeast and algae biomass
Bočán, David ; Byrtusová, Dana (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis was focused on optimalization of extractions of active compounds from microalgae and carotenogenic yeasts. Other part of this work was focused on characterization of these extracts and their tests of cytotoxicity on human keratinocytes. In theoretical part a literary research which summarizes the basic properties and cultivation conditions of used microorganisms was conducted. Then there were listed an examples of antioxidant compounds found in these microorganisms as well as their properties. Finally the term cytotoxicity and methods of its measurement were clarified. The practical part of this thesis consists of series of extractions from mentioned microorganisms. These extracts were characterized by the content determination of phenolic and flavonoid compounds and also chlorophyll and carotenoid compounds. Determination of antioxidant capacity and SPF were done too. Lastly the cytotoxicity of chosen extracts was measured using the MTT test.
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Influence of stress and nutritional conditions on carotenogenic yeast and microalgal metabolism
Sikorová, Pavlína ; Byrtusová, Dana (referee) ; Szotkowski, Martin (advisor)
This bachelor thesis describes the infuence of biological stress (co-cultivations) on the growth and metabolism of selected carotenogenic yeasts and microalgae. The metabolites of these microorganisms are chlorophyll and carotenoids, which are natural pigments and antioxidants. In theory, co-cultivation is a cultivation where microorganisms mutually support each other in the growth and production of metabolites. This would cause the increased production of previously mentioned chlorophyll and carotenoids. The theoretical part of the work is focused on the description of selected species of yeasts and microalgae and further discusses in more detail, the topics of stress factors depending on the growth and metabolism of microorganisms. The experimental part then deals with different types of cultivation and cocultivation and tries to optimize the production media and find the best symbiotic yeasts and microalgae. Furthemore the issue of different ratios of microorganisms in co-cultivations is also addressed here. The cultivated yeasts strains were Rhodotorula kratochvilovae, Rhodosporidium toruloides and Phaffia rhodozyma. And microalgae strains were Desmodesmus acutus, Desmodesmus quadricauda, Coccomyxa sp., Chlorella sorokiniana, Chlamydomonas reinhardtii and Scenedesmus obliquus. Cultivated cyanobacterium was Synechoccocus nidulans. The most successful co-cultivation experiment was the one with R. kratochvilovae and yeast Desm. quadricauda. This experiment was very succesful in all aspects.
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Evaluation of modifications in content of selected bioactive substances in flax (\kur{Linum usitatissimum} L.) seeds during germination
HAŠKOVÁ, Kateřina
This thesis focus on analysing effect of germination on some groups of bioactive compounds in flaxseed. We used flaxseed variety named Libra. Its germination was 10 days long, done in two different conditions: in the dark and fully iluminated for 24 hours daily. Samples were taken on 2nd, 4th, 6th, 8th and 10th day. Following analyses were performed: determination of dry matter content, lipid content, content of nitrogenous compounds, content of proteins and protein spectrum, chlorophyll content, content of total polyphenolic compounds and antioxidant activity. Content of dry mater was proved to decrease during germination as well as lipid content regardless of light conditions. Amount of nitrogenous compounds stayed relatively unchanged during germination. Whereas amount of proteins increased depending on duration of germination and light conditions. Hydrolysis of proteins during germination was proved by protein spectrum analysis. Content of chlorophyll inreased in light-germinated seeds only. Increasing effect of germination on total polyphenolic compounds content and antioxidant activity was proven as well. Moreover aproximately two-fold rise of values was reported after defatting of samples.
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Analysis of parameters presumably associated with drought-resistance in various sorghum genotypes
Panchártek, Daniel ; Holá, Dana (advisor) ; Hniličková, Helena (referee)
The aims of this work were 1) to assess whether sorghum (Sorghum bicolor (L.) Moench) genotypes originating from the India can be grown and analyzed in the climatic conditions of central Europe and 2) to find out the utilization potential of selected non- destructive and destructive methods based mostly on the chlorophyll a fluorescence measurements and the determination of photosynthetic pigments' content for the differentiation of sorghum genotypes based on their presumed drought tolerance. Field experiments made during 2 years compared 15 genotypes of this species (2 stay-green parental lines, 2 senescent parental lines and 11 introgression lines with stay-green loci), 2 of these genotypes were further analyzed in greenhouse conditions where the water deficit was induced by a cessation of watering for 12 days. The field-grown plants showed some differences between individual genotypes in all measured parameters; however, for the majority of the genotypes these differences were not statistically significant. The stay-green parental genotype B35 differred the most from the other ones in both field seasons, but the other stay-green genotypes usually did not differ from the senescent genotypes. No significant differences between both greenhouse-tested genotypes (presumably contrasting in their...
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Dyes of red and white wine cultivars
Peprná, Tereza ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Theoretical part of this bachelor thesis contains informations about dyes of red and white grape species. At the beginning there is described component composition of grape berry. The biggest attention was paid to colour of red wine species. It deals with their common characterization, stabilization of their behaviour during production and storage wine. This work includes short recherche of their determination methods. Than there are mentioned colour of white wine cultivars. In another chapter there are described process of freeze drying otherwise lyophilization procedure. This method was used in experimental part while grape sample manufacturing. Grapes were immediately frozed on the dry ice after their separation. Skins were separated from pulp in nitrogen atmosphere and than these skins were lyophilizated.
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