National Repository of Grey Literature 73 records found  beginprevious21 - 30nextend  jump to record: Search took 0.02 seconds. 
Production and characterization of immunologically active microbial beta-glucans by yeast.
Gerspitzerová, Nela ; Šimanský, Samuel (referee) ; Szotkowski, Martin (advisor)
The aim of this bachelor thesis is to study the effect of different cultivation conditions on the production of biomass, beta-glucans, lipids, carotenoids and other metabolites in selected strains of carotenogenic yeast. The thesis is divided into two main parts, a theoretical one and an experimental one. Theoretical part contains a characterisation of beta-glucans, their sources and uses, furthermore a description of the selected yeast genera and other metabolites they produce and finally possible analytical methods of these compounds. Experimental part describes the cultivation, analysis and obtained results. During the first experiment, the yeast strains were cultivated in production media with different C/N ratio, during the second experiment, the yeasts were cultivated either at room or at lower temperature with different content of phosphorus in the media. The selected strains of yeast were Rhodotorula glutinis, Rhodotorula mucilaginosa, Rhodosporidium toruloides, Cystofilobasidium macerans, Sporidiobolus metaroseus and Sporidiobolus pararoseus. Increasing C/N ratio generally had a positive effect on the production of lipids, while exhibiting the opposite effect on carotenoids, it did not have an unequivocal effect on the amount of beta-glucans. It was discovered that lowering the cultivation temperature had a significant negative effect on the production of all observed metabolites. Increased content of phosphorus in production media positively influenced the production of biomass and beta-glucans in most strains, on the other hand the highest amount of carotenoids was reached at lower concentration of phosphorus. The amount of phosphorus had almost no effect on the production and the profile of lipids. The highest amount of beta-glucans in biomass was discovered in C. macerans, their biggest production was reached by R. toruloides. The strain S. metaroseus was the most suitable for accumulation of lipids in its biomass. The highest amount of total carotenoids was reached by R. mucilaginosa.
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.
A comparison of metabolic activity and use of microalgae and pigment-formed yeasts
Szotkowski, Martin ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
Carotenoids are natural pigments occurring in plants and many microorganisms, such as algae, yeast and bacteria. They represent the most common group of antioxidants with significant biological effect. Lipids are an essential component of all living organisms. They are the source and the reservoir of energy for organisms, which can also be used in the petrochemical industry for the production of biofuels. This thesis deals with the production properties of carotenoids and lipids by selected strains of yeasts, algae, and canobacteria, in order to apply the acquired knowledge and find cheap suitable alternatives for microbial biotechnological production of these metabolites using waste substrates. Carotenoids, coenzyme Q, and ergosterol in cells were determined by liquid chromatography. The lipid content and fatty acid profile was analyzed by gas chromatography. Cell morphology and localization of selected metabolites were analyzed by fluorescence lifetime imaging microscopy. In this work yeast genera Sporobolomyces, Cystofilobasidium and Rhodotorula were used. As the representatives of the algae and cyanobacteria strains of Desmodesmus, Cyanothece, Chlamydomonas, Synechoccocus and Chlorella strains were studied. In the overall comparison, the yeast strains were more productive than algae and cyanobacteria. The highest carotenoid production was found in S. pararoseus, C. capitatum and R. mucilaginosa cells, while the highest lipid yield was observed in strains of C. infirmominiatum and S. metaroseus.
Production of lipids by different yeast strains
Ponížil, David ; Byrtusová, Dana (referee) ; Szotkowski, Martin (advisor)
The bachelor's thesis is focused on the cultivation of selected species of yeast. It is proven that these lipids have many uses and can be applied in the production of biofuels or food industry products. Lipids are forming basic biomolecules that are part of biomembranes in living organisms. The theoretical part describes the structure, chemical composition, and nutrition of these microorganisms. Furthermore, this work contains the characteristic not only of the yeast strains used but also of the lipid metabolites. The experimental part is focused on the description of the preparation of the culture medium designed for yeast growth. The total proportion of lipids and lipid metabolites in the biomass was monitored and compared to individual yeast strains grown on culture media with different compositions. The yeast was cultivated on mediums with carbon and nitrogen from different sources and in different ratios. Waste substrates were also used as carbon and nitrogen sources to compare them to conventional sources. The profile of fatty acids produced by selected yeasts was compared to the fatty acids contained in vegetable oils and butter. The series of experiments showed that the largest proportion of lipids in biomass was observed in the strain Rhodosporidium toruloides grown on a waste substrate of animal fat.
Characterization of biological effects of extracts obtained from yeasts and autotrophic microorganisms
Špačková, Dominika ; Bendová, Agáta (referee) ; Szotkowski, Martin (advisor)
Carotenogenic yeasts and microscopic autotrophic microorganisms are increasingly being studied in the biotechnology industry because of their ability to produce a variety of substances with a wide range of utilization. These substances mainly include lipids and carotenoids, which are used in the food and pharmaceutical industries. The aim of this bachelor thesis is to determine the way these microorganisms behave in the presence of stress factors, and which of them would have a positive effect on the production of metabolites that can be further used in various industries. The theoretical part is dedicated to a characterization of substances produced by carotenogenic yeasts, cyanobacteria and microalgae, which will be further analyzed in the experimental part. The metabolites mainly include carotenoids, which are a wide group of naturally occurring pigments that possess, among other things, antioxidant and provitamin activity. No less important substances produced by these organisms are lipids, which are part of cell membranes, they also serve as a reservoir of energy, and the substances contained in lipids are part of the precursors of many hormones. Yeast cell walls also contain -glucans, which have many beneficial effects on immunity and human health. Due to this fact, interest in their research have been rising recently. The analytical methods used to determine these substances are also mentioned, as well as stress factors and their effects on the cells of the mentioned organisms. The experimental part deals with the exposure of these microorganisms to oxidative stress and stress caused by heavy metals. The aim was to analyze which concentrations of these stress factors are lethal to microorganisms, and which of them are optimal for increase of the production of the above-mentioned substances. Of the yeast strains, the strains Sporidiobolus pararoseus and Rhodotorula mucilaginosa achieved increased production of metabolites due to selenate ions. In contrast, cobalt had a beneficial effect only on the accumulation of lipids and -glucans in cells. The positive effect of selenium was also observed in the strain Chlorella minutissima and Arthrospira maxima, however, the most remarkable changes in the production of metabolites were achieved by the addition of the optimal concentration of the solution inducing oxidative stress.
The optimalization of bacterial cellulose production
Stříž, Radim ; Szotkowski, Martin (referee) ; Kovalčík, Adriána (advisor)
This diploma thesis focuses on the optimization of bacterial cellulose production by Komagateibacter xylinus DSM 46604. The theoretical part of this thesis describes the properties of bacterial cellulose, its production and application possibilities. The experimental part aimed to assess the effect of different cultivation conditions on the production yields of bacterial cellulose. The effects of several cultivation strategies have been studied such as: (1) effect of acetate buffer used as a medium, (2) impact of oil added into the medium, (3) fed-batch cultivation, (4) variation of the volume of cultivation vessel and cultivation media and (5) aeration. In addition to the production of relatively thin samples, up to 100 µm was synthesized unique 3D structured bacterial cellulose in the form of cylinders, with a height up to 2 cm. The growth of bacterial cellulose in the form of cylinders was achieved by dynamically cultivating K. xylinus in combination with fed-batch approach.
Characterization of plum oil and its use in cosmetics
Kaňovská, Zuzana ; Němcová, Andrea (referee) ; Szotkowski, Martin (advisor)
The aim of this bachelor thesis was to characterize plum kernel oil and to explore its possible use in the cosmetics industry. The theoretical part of the thesis is a research on the properties of vegetable oils in general, plum kernel oil and other kernel oils. In the experimental part, the oil was characterized in terms of the profile of fatty acids, phenolic compounds and tocopherols. Body lotion was also prepared, containing plum kernel oil, for which hydration and barrier properties were determined. Pure plum kernel oil and body lotion were tested for antimicrobial activity.
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.
Use of rare oils in cosmetics
Pilipenco, Alina ; Szotkowski, Martin (referee) ; Němcová, Andrea (advisor)
The purpose of this bachelor thesis was to research rare oils. The oils from selected plants (poppy, cannabis, thistle) is characterized by the content of active phenolic compounds, fatty acid composition, antioxidant and antimicrobial effects. First part of the thesis is a literary research on a given topic, which contains the following parts: the universal chemical composition of vegetable oils, the characteristics and effects of selected oils and the ways of their obtaining for cosmetic purposes. The experimental part is focused primarily on the basic analysis of selected oil components and the preparation of the shower oil based on the obtained results. In conclusion are presented an overview of all the properties of selected oils, their practical use and assessment of their application in cosmetics.

National Repository of Grey Literature : 73 records found   beginprevious21 - 30nextend  jump to record:
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1 Szotkowski, Marek
4 Szotkowski, Matěj
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