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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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Transformation of brewery industry waste by carotenogenic yeasts
Šnejdrlová, Kateřina ; Šimanský, Samuel (referee) ; Holub, Jiří (advisor)
Carotenoids are one of the metabolites produced by carotenogenic yeasts. These are valuable substances that are used in the food and pharmaceutical industries. The use of waste and by-product as substrate for cultivation of carotenogenic yeasts can reduce the overall cost of carotenoid production. The by-products of the brewing industry, due to their nutritional composition, appear to be suitable materials for use in the cultivation of microorganisms. The work is divided into theoretical and practical parts. The theoretical part focuses on the description of yeasts, their metabolites and individual substrates. The practical part focuses on the cultivation of carotenogenic yeasts on brewer's spent grain hydrolysate and on yeast extracts prepared from brewer's spent yeast. Following yeasts were used in the practical part: Cystofilobasidium infirmominiatum CCY 17-18-4, Sporidiobolus salmonicolor CCY 19-4-25, Sporobolomyces shibatanus CCY 19-9-6, Rhodotorula kratochvilovae CCY 20-2-26, Rhodotorula mucilaginosa CCY 20-7-31, Rhodotorula toruloides CCY 62-2-4. The results obtained in this work using advanced chromatographic methods suggest that treated brewer's spent grain and yeast extract prepared from brewer's spent yeast are suitable substrates for the cultivation of carotenogenic yeasts. The prepared yeast extract can also serve as a source of total nitrogen during cultivation, without negatively affecting the monitored parameters.
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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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Biotechnological production of yeast metabolites under combined stress
Baťková, Zuzana ; Byrtusová, Dana (referee) ; Dzurendová, Simona (advisor)
This master's thesis focuses on utilizing waste whey for the biotechnological production of carotenogenic yeast biomass and its valuable metabolites such as carotenoids, ubiquinone, ergosterol, fatty acids, and -glucans. Combined stress conditions were used to evaluate the influence on the yeast biomass metabolites production. These metabolites find applications in various industries, for example pharmaceutical, cosmetic, and food. The thesis is divided into theoretical and experimental parts. The theoretical section describes the composition of whey and its valorization in various industries. Selected carotenogenic yeasts and their metabolites are also presented. Furthermore, the impact of nutritional, oxidative stress, and the influence of metals on the production of yeast biomass and metabolites are described. The experimental part is reporting the whey treatment, yeasts biomass production and methods for the determination of individual metabolites. Five strains of red yeasts were used in this thesis: Cystofilobasidium macerans (CCY 10-1-2), Phaffia rhodozyma (CCY 77-1-1), Sporobolomyces shibatanus (CCY 19-9-6), Rhodotorula kratochvilovae (CCY 20-2-26) and Rhodotorula toruloides (CYY 62-2-4). The strain Cystofilobasidium macerans showed the best results for the utilization of whey substrate under the influence of combined stress, especially in biomass, lipid, and -glucan production. A promising strain in carotenoid production under combined stress was Sporobolomyces shibatanus.
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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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Production of selected metabolites by yeasts and algae cultivated under stress conditions
Mariničová, Veronika ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
The presented work was focused on the comparison between the production of selected metabolites by carotenogenic yeasts and microalgae cultivated under conditions of external stress. The main metabolites of interest were carotenoids, further lipophilic substances and lipids. Biotechnological overproduction of these metabolites could serve as a source of potentially beneficial substances not only for the pharmaceutical, cosmetic and food industries, but also for the production of third generation biofuels. Recently, there has been a growing interest in biofuels primarily from microalgae, which have a high potential in biofuel production and seem to be a promising source. The theoretical part deals with the description of individual genera of carotenogenic yeasts, microalgae, cyanobacteria, chemical composition of produced metabolites and brief biosynthesis. In addition, individual methods for analyzing the production of the metabolites of interest were described. The experimental part is focused on the comparison of production of carotenoids, coenzyme Q, ergosterols (phytosterols) and lipids by yeasts, microalgae and cyanobacteria. As a source of external stress, temperature, salt and light stress were chosen. The strains of Rhodotorula glutinis, Rhodotorula mucilaginosa, Sporidiobolus pararoseus and Cystofilobasidium macerans were studied from the yeast strains. Microalgae and cyanobacteria were Scenedesmus obliqus, Scenedesmus dimorphus, Chlorella sorokiniana, Chlorella saccharophila, Botryococcus brauni, Synechococcus nidulans and Arthrospira maxima. The yeast and algal strains were optimized for growth, carotenoid and lipid production. Applied salt stress showed a significant liquidation effect on algal and cyanobacterial strains. The thesis also monitored the biological stress, so-called co-cultivation of microalgae and yeasts. Further experiments will be the subject of future work.
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Cultivation of microalgae and carotenogenic yeasts under stress conditions
Sniegoňová, Pavlína ; Skoumalová, Petra (referee) ; Szotkowski, Martin (advisor)
In biotechnological industry we can register greater use of microorganisms like microalgae and carotenogenic yeast for production of selected substances or for valorisation of waste materials. Among metabolites produced by these microorganisms are carotenoids, which are natural pigments with antioxidant and other biological effects. Other significant produced substances are lipids, which represent large range of substances in living organisms. They form cellular membranes and serve as a reservoir of energy. These substances can be used in food, cosmetic and pharmaceutical industry and also in production of biofuels. Theoretical part is focused on description of selected genera of microorganisms, their cultivation and produced metabolites. Stress factors to which they were exposed are also mentioned, as are the analytical methods used for detection of produced metabolites. Next part is dedicated to the comparison of production properties of selected microorganisms depending on used stress factor. Increased production of lipids in yeast is observed in C. macerans and S. metroseus with higher concentrations of FeCl3. While using whey as a source of ccarbon, yeasts show decreased production of carotenoids. Highest production of lipids in algae and cyanobacteria was observed in S. acutus and D. quadricaudea. Production of carotenoids depended on applien stress factor and highest productions was observed in C. sorokiniana, C. reinhardtii, D quadricaudea and Coccomyxa sp.
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Study of red yeast metabolism on molecular level
Roubalová, Monika ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
This master thesis is focused on the molecular characterization of the eight red yeasts species. For molecular characterisation, the most variable rDNA regions ITS1, 5,8S ITS2 and the region encoding the large ribosomal subunit (26S) were amplified. This long region of the yeasts DNA was sequenced and compared by NCBI database for identification. The red yeasts identification was confirmed by data from DGGE method. Another aim of this thesis was to select the best yeasts producer of carotenoids and triacylglycerols. Rhodosporidium toruloides was found as the best producer and, thus, this strain was subjected to random mutagenesis by UV irradiation. The results of the production of metabolites by R. toruloides were compared with mutant strains, which were also adapted to the glycerol and waste whey substrates. The mutant strain G33 was found as the best producer of total carotenoids with a yield of 7.14 mg.g-1 of biomass. The highest production of ergosterol was demonstrated by the mutant strain Y34, the ergosterol yield was 47.72 mg.g-1 of biomass. The wild type of R. toruloides was able to produce the highest amount of both carotene (2.42 mg.g-1 of biomass) and TAG (76.32 mg.g-1 of biomass) on glucose medium.
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