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Influence of some microbiogenic elements on carotenogenic yeasts
Pulkrábek, Josef ; Holub, Jiří (referee) ; Obračaj, Jan (advisor)
Carotenogenic yeasts of the genus Rhodotorula are well known for their production of a variety of economically valuable and otherwise difficult to produce compounds such as fatty acids, carotenoids, ergosterol, and ubiquinone. This study investigates the effect of the addition of select microbiogenic elements (Fe, Se, I) and their combinations into mineral cultivation media on the production of the mentioned valuable metabolic products and the rate of element sorption into the biomass of the strains of Rhodotorula mucilaginosa, Rhodotorula kratochvilovae, and Rhodotorula toruloides. Additionally, the sorption of zinc oxide, ferrous fumarate, and selenomethionine into previously cultivated biomass was measured with sorption times of 2 and 24 hours. Fatty acid content was determined using GC-FID, while carotenoids, ergosterol, and ubiquinone were analyzed using HPLC-DAD, with element content being quantified using ICP-OES and IC. With a few exceptions, the production of metabolic products was decreased with the addition of elements into the media and inversely correlated with their concentration. Higher concentrations generally showed greater absolute amounts of sorbed elements but lower relative amounts, which, combined with reduced production of metabolic products shows that the media are not ideal for the cultivation of the given species. The elemental contents were such that biomass supplemented with individually sorbed elements would vaguely align with ESFA dietary reference values, but cultivation in media with a mixture of added elements could result in the biomass containing either insufficient iron or excessively high levels of selenium. Sorption levels were relatively low (5 to 22 % for iron and 0.5 to 2.5 % for selenium). Indicating that cultivation in media with lower concentrations of elemental additives is a promising area for future research.
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Optimization of the co-cultivation of the yeast Phaffia rhodozyma with selected strains of autotrophic microorganisms
Shelekhova, Olga ; Sniegoňová, Pavlína (referee) ; Sikorová, Pavlína (advisor)
This bachelor thesis was focused on the cultivation of Phaffia rhodozyma yeast on different carbon sources in laboratory conditions and on the optimization of co-cultivation conditions of Phaffia rhodozyma yeast strain with selected strains of autotrophic microorganisms on media with the most suitable carbon sources. The yeast strains of microorganisms under study were the yeast Phaffia rhodozyma (CCY 77-1) and the microalgae Desmodesmus communis (CCALA 464). Cultures were carried out on media containing glucose, glycerol, coffee oil, frying oil, ethanol, isopropanol, methanol, molasses, and waste alcohol. The work is divided into two main parts, theoretical part, and practical part. The theoretical part includes information about the yeast and microalgae genus used, description of waste substrates, metabolites monitored and methods of analysis of these substances. The experimental part focuses on cultivation, co-cultivation and optimization of production media. Cultivation conditions, biomass processing, metabolite analysis and the results obtained have been described
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Production of lipids and lipid-soluble compounds by some yeasts and algae
Šimanský, Samuel ; Rapta, Marek (referee) ; Márová, Ivana (advisor)
The submitted bachelor thesis focuses on production of lipids and lipid-soluble compounds by selected strains of carotenogenic yeasts, autotrophic algae and cyanobacteria. Different forms of stress were applied on selected strains and its influence was subsequently compared. The theoretical part deals with the processing of knowledge about selected strains of yeast, algae and cyanobacteria. There are also mentioned the selected metabolites (lipids, carotenoids, ergosterol, ubiquinone and chlorophyll) and the possibilities of their determination. The experimental part deals primarily with the influence of nutritional stress on the production of selected metabolites and the yeast biomass, namely their growth properties on waste fat. Furthermore, there was monitored the effect of elevated and reduced temperature on the cultivation of yeasts, algae and cyanobacteria. Osmotic stress experiments were also carried out by the addition of NaCl. As the most suitable strain for decomposition of the waste fat was selected Sporidiobolus pararoseus, particularly because of its high content of carotenoids, ergosterols and ubiquinone in biomass. Changes in temperature, or increased osmotic pressure had in the most cases a negative effect on biomass production.
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Optimization of cultivation of carotenogenic yeasts on mixed waste substrates
Holub, Jiří ; Mikulíková, Renata (referee) ; Márová, Ivana (advisor)
The master thesis addresses the issue of cultivation of selected strains of carotenogenic yeasts on waste materials of the food industry using a laboratory bioreactor. Carotenogenic yeasts are able to produce highly valuable metabolites during cultivation, which are located predominantly in the lipid part of the cells. Particularly, they are carotenoids, ergosterol, coenzyme Q and fatty acids. The thesis is divided into two main parts, the theoretical part and the practical part. The theoretical part describes individual yeast strains, types of waste materials, produced metabolites and methods of their analysis. The experimental part deals with the processing of waste materials of the food industry, specifically animal fat, whey and spent coffee grounds into the form of substrates usable as nutrition sources for yeast cultivation. Furthermore, cultivations focused on the recovery of the monitored metabolites and their analysis by using HPLC/PDA and GC/FID assemblies were studied as well. The yeast strains Rhodotorula mucilaginosa (CCY 19-4-6), Rhodotorula kratochvilae (CCY 20-2-26), Rhodosporidium toruloides (CCY 062-002-001), Sporidiobolus pararoseus (CCY 19-9-6) a Cystofilobasidium macerans (CCY 10-1-2) were used in this work. As one of the best producing strains Sporidiobolus pararoseus (CCY 19-9-6) was found, which achieved very high productions of carotenoids, coenzyme Q and ergosterol.
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Metabolic adaptation of carotenogenic yeasts to nutritional stress induced by selected wastes of the food industry
Plhalová, Žaneta ; Šimanský, Samuel (referee) ; Szotkowski, Martin (advisor)
This bachelor thesis deals with the production of carotenoids and lipids by selected strains of carotenogenic yeasts cultivated on waste substrates of the food industry. The production properties of the yeast strains Sporidiobolus pararoseus, Sporidiobolus metaroseus, Cystofilobasidium macerans, Rhodotorula mucilaginosa, Rhodotorula kratochvilovae and Rhodosporidium toruloides were studied. The cultures were cultivated by using waste products of food industry: waste frying oil, coffee oil which was obtained by extraction from coffee grounds and waste animal fat from rendering plants. The work consists of two main parts. The theoretical part describes the individual genera of yeasts, monitored metabolites, waste products and methods of analysis of monitored metabolites. The experimental part is focused on the processing of used waste substrates, cultivation of yeasts, acquisition and processing of biomass and analysis of metabolites. Rhodosporidium toruloides and Sporidiobolus pararoseus strains were the most suitable for the production of carotenoids on waste substrates. The highest production of lipid substances was measured in the strain Sporidiobolus pararoseus.
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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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Characterization of extracellular enzymes and other metabolites of carotenogenic yeasts
Těšíková, Karolína ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
Lipases are enzymes catalyzing primarily the hydrolytic cleavage of triacylglycerol bonds. The production of lipolytic enzymes is known in many microorganisms, especially those who are able to utilize a fatty carbon substrate. Some genera of carotenogenic yeasts are characterized by this ability. Carotenogenic yeasts are characterized primarily by the formation of intracellular carotenoids, lipids and lipid-soluble substances. In addition to these metabolites, they may also produce some biosurfactants. This work deals with the production of extracellular lipolytic enzymes and biosurfactants by carotenogenic yeasts Rhodotorula glutinis, Cystofilobasidium macerans, Rhodotorula mucilaginosa and Sporidiobolus pararoseus cultivated mainly on animal waste fat at various C/N ratios (13, 25, 50, 100). Lipase activity was detected in all strains studied. Enzyme activities were measured by spectrophotometric method. Lipase induction has also been observed during cell growth, where several peaks of lipase activity have been reported, suggesting cell-associated lipase and lipase secreted into the environment. Lipase activities have also been found in cultures on glucose and glycerol carbon substrates. Further, the molecular characterization of lipolytic enzymes was performed using polyacrylamide gel electrophoresis. The formation of biosurfactants is to some extent formed by all strains. In particular, the biosurfactants of C. macerans and S. pararoseus yeast have emulsifying and solubilizing properties. Simultaneously with the production of lipase and biosurfactants, the production of characteristic high value added intracellular metabolites in S. pararoseus and R. mucilaginosa was evaluated too.
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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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Production of pigments and lipid substances by microorganisms on waste substrates of the food industry
Hladká, Dagmar ; Němcová, Andrea (referee) ; Szotkowski, Martin (advisor)
The presented study is focused on production of carotenoids, lipids and other substances by carotenogenic yeasts and autotrophic algae. Studied strains were cultivated in media with different composition, including waste substrates from food industry. Studied strains were cultivated under stress conditions to enhance the production of desired metabolites. The theoretical part deals with the information about yeasts and algae, with the information about monitored metabolites such as lipids, carotenoids, ergosterol, ubichinon or chlorophyll. Furthermore, the theoretical part deals with possible methods of metabolite analysis. The experimental part deals with the description of cultivation of yeats and algae. Also experimental part is focused on the description of individual methods. The result part deals with comparition of production of biomass, metabolits and lipids. The selected strains of yeast were Sporidiobolus pararoseus, Sporidiobolus metaroseus, Sporobolomyces roceus, Phaffia rhodozyma and Dioszegia hungarica. The selected strains of algae were Desmodesmus acutus, Desmodesmus quadricauda, Scenedesmus dimorphus and Chlamydomonas reinhardtii. We were optimized conditions for metabolites and lipids production. Optimal medium, which contained coffee hydrolyzate was with carbon to nitrogen ratio C/N 25. Nitrogen in higher concentration had negative effect on production of lipids. The most suitable strain for effective use of nitrogen in different concentrations was Chlamydomonas reinhardtii. The most suitable strain of yeast for effective use of coffee hydrolyzate was Sporidiobolus metaroseus.
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Production of carotenoids and other metabolites by yeast using selected food wastes.
Chujanov, Oleg ; Šimanský, Samuel (referee) ; Szotkowski, Martin (advisor)
This bachelor thesis is focused on the issue of yeast cultivation with the usage of waste sub-strates from the food industry on a laboratory level. Carotenogenic yeasts are microorganisms capable of processing food waste substrates and use them as a source of organic nutrients for growth. This thesis consists of a practical as well as theoretical part. The experimental section focuses on the description of different strains of yeasts, metabolites and types of waste sub-strates. The two main substrates chosen for this research were chicken fat and chicken fe-athers. The yeast types used in this thesis were Rhodotorula kratochvilovae (CCY 20-2-26), Rhodosporidium toruloides (CCY 62-2-4), Cystofilobasidium macerans (CCY 10-1-2), Spo-ridiobolus pararoseus (CCY 19-9-6), Rhodotorula mucilaginosa (CCY 20-9-7), Rhodotorula mucilaginosa (CCY 19-4-25) and Sporidiobolus metaroseus (CCY 19-6-20). These strains reported high production values of the metabolites researched in this thesis. The strains Rho-dosporidium toruloides (CCY 62-2-4) and Sporidiobolus metaroseus (CCY 19-6-20) were chosen for the production of metabolites from waste substrates, for those reported the most promising results.
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