National Repository of Grey Literature 47 records found  1 - 10nextend  jump to record: Search took 0.01 seconds. 
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.
Interaction of yeast and microalgae extracts with cell cultures
Serikbay, Adilkhan ; Holub, Jiří (referee) ; Márová, Ivana (advisor)
The objective of this bachelor thesis was to optimize the extracting of bioactive compounds from microorganisms for the purpose of characterizing and evaluating their cytotoxicity on human cell line HaCaT. During the characterization phase, extract samples were analyzed using spectrophotometric techniques. After exposing the cell line to selected extracts, a cytotoxicity test was performed to assess cell viability using MTT analysis. The theoretical part encompassed an extensive literature review focused on cultivation techniques, human cell lines, cytotoxicity analysis, and viability assessments. The practical section provided a detailed exploration of contemporary extraction techniques utilizing a wide range of both polar and non-polar solvents to enhance the efficiency of extracting active compounds from the yeast strain Rhodotorula toruloides and microalgae Chlorella vulgaris. Active compounds such as ubiquinone, ergosterol, lycopene, and torularhodin were identified in the yeast, while the microalgae were found to contain lutein, chlorophylls, as confirmed by HPLC analysis. The biocompatibility of the optimized extracts from selected strains was verified using the MTT assay on HaCaT cell lines. The aqueous extract from microalgae Chlorella vulgaris exhibited lower toxicity to HaCat cell line, with viability rates exceeding 85%. Yeast extracts from Rhodotorula toruloides initially showed higher viability rates, which, however, decreased with increasing extract concentrations.
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.
Production of pates with the addition of mushrooms
Tóthová, Martina ; Holub, Jiří (referee) ; Mikulíková, Renata (advisor)
This bachelor thesis deals with the sensory evaluation of pâté with mushrooms. First the 3 samples of pâtés were made to select the right concentration of mushrooms for sensory evaluation. Then the 7 samples of pâtés which contained different texture and types of mushrooms were produced. In the theoretical part pâtés are characterised, their manufacturing and types of pâtés are described. The part of literature search is description of mushrooms in general, their composition and description of mushrooms which were used for production of pâtés. Another topic is description of conditionals and methods of sensory analysis. The experimental part is focused on the production of pâtés for two sensory analyses, evaluating the heat treatment and sensory analysis. The content of vitamin D in the samples of pâtés was analysed by liquid chromatography. Processing of results of sensory analysis of pâtés was determined that the best samples were pâtés with milled champignons and champignons which were add in blender.
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.
Remote control and visualization of bus-systems KNX and DALI for building management
Holub, Jiří ; Macháček, Jan (referee) ; Bátora, Branislav (advisor)
The thesis is focused on bus systems and their control by GUI. Basic energy management principles and the mostly known bus systems are analysed in the first – theoretical part of the paper. The theoretical part is then focused on software tool ETS 4, which is used for activation of system installation KNX. Software tool SmartServer, which is used for communication between bus system KNX and web interface, is described at the end of the first theoretical part. Two laboratory boards assembled of KNX and DALI parts were constructed in the second – practical part. Three laboratory tasks, which are prepared so they are related to theoretical description in previous part, were submitted in next step. Aim of the first task is to introduce basics of the board and PriOn interface. The second task is focused on DALI components and temperature control with PriOn regulating device. Creating of basic visualization and controlling of the board with SmartServer is described in the last task.
High-specific speed hydraulic turbine
Holub, Jiří ; Haluza, Miloslav (referee) ; Rudolf, Pavel (advisor)
The aim of this thesis is to design a geometry of runner of high specific speed turbine which is supposed to provide the maximum flow rate of the turbine while achieving a relatively high hydraulic efficiency. New design is based on the analysis of the hydraulic characteristics of three previous design sof very hiát specific speed turbines. The actual hydraulic pdesign of the turbine runner is based on CFD computations. Special software tools like BladeGen and TurboGrid were used for petting up the geometry and mesh for the very first time at Kaplan Department of Fluid Engineering.
Production of carotenoids grown on waste fat
Holub, Jiří ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
Carotenoids are lipid-soluble pigments which are contained in plants and microorganisms. Carotenoids are known for their antioxidant effects. Lipids are predominantly non-polar substances, which are essential and present in all types of organisms. The research was made by theoretical and practical form. It was dealing with production of carotenoids pigments and different lipophilic substances by yeasts of Rhodotorula glutinis, Rhodosporidium toruloides and Sporidiobolus metaroseus, cultivated in media containing waste fat or glycerol. Further, methods for obtaining lipid substances from microorganisms and with further analysis of samples by gas or liquid chromatography were optimized. The main task of the research was to find out which types of media and yeasts are the most suitable for production of lipid substances. For production of lipid substances in glycerol media, as the best producing strain Rhodosporidium toruloides was found, which simultaneously reported the highest concentrations of carotenoids on fatty and fatty hydrolyzed media.
Superresulution of photography using deep neural network
Holub, Jiří ; Přinosil, Jiří (referee) ; Burget, Radim (advisor)
This diploma thesis deals with image super-resolution with conservation of good quality. Firstly, there are described state of the art methods dealing with this problem, as well as principles of neural networks with focus on convolutional ones. Finally, there is described a few models of convolutional neural network for image super-resolution to double size, which have been trained, tested and compared on newly created database with pictures of people.
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.

National Repository of Grey Literature : 47 records found   1 - 10nextend  jump to record:
See also: similar author names
13 HOLUB, Jan
22 HOLUB, Jiří
1 Holub, J.
1 Holub, Jakub
13 Holub, Jan
1 Holub, Jaroslav
7 Holub, Josef
4 Holub, Juraj
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