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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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Study and optimization of mixotrophic growth of selected strains of autotrophic microorganisms
Miheeva, Alexandra ; Sikorová, Pavlína (referee) ; Sniegoňová, Pavlína (advisor)
This bachelor thesis investigated the production of microalgal metabolites in response to stress conditions. In recent decades, there has been a growing interest in the research and application of algae in various fields such as food, cosmetic, pharmaceutical, biotechnology and energy industries. The microalgae strains selected for this work are Desmodesmus quadricaudea (CCALA 464), Chlorella minutissima (CCALA 916), Desmodesmus subscapitus (CCALA 688), Scendesmus pleiomorphus (CCALA 460). The theoretical part of the work focuses on the description of selected genera of microorganisms, conditions of their cultivation and metabolites produced. Furthermore, stress factors and analytical methods used to identify and quantify the produced substances are discussed. In the practical part of the thesis, the cultivation procedure, biomass processing and metabolite analysis are described, together with a presentation of the results obtained. Algal strains Desmodesmus subscapitus, Scenedesmus pleiomorpfus and Chlorella minutissima showed the highest alcohol consumption in HPLC-RI analysis, making them the most suitable candidates for possible mixotrophic cultivation. Growth optimization of Chlorella minutissima was also performed and analyzed in this work. Its results are presented in the practical section.
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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.
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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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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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Characterization of selected complex vitamin supplements
Bandarenka, Andrei ; Fialová, Lenka (referee) ; Márová, Ivana (advisor)
Modern society places great emphasis on a healthy lifestyle and balanced diet, leading to increased interest in products with high levels of vitamins, minerals, and other health-promoting substances. Consequently, there has been an increased interest in various dietary supplements, including so-called "greens" products. These supplements are designed to provide a concentrated source of nutrients from various green plants while also containing a high proportion of vitamins, minerals, antioxidants, and other bioactive compounds. The aim of this thesis is to characterize complex food supplements in terms of their composition and content of active ingredients to better understand their mechanisms of action and identify substances responsible for their health-promoting effects. The theoretical part of the work focuses on describing legislation of dietary supplements, including their characteristics and the evolution of interest in them over recent decades. Furthermore, the theoretical part addresses the description of basic components commonly found in supplements, such as vitamins, plants, algae, prebiotics, and probiotics. Finally, methods for determining these components and the most frequently used techniques for their analysis are described. In the experimental part, 12 different plant-based dietary supplements falling into the category known as "greens" were selected. The content of phenolic compounds, chlorophylls, carotenoids, and antioxidants were determined in these products. Additionally, the influence of these products on the growth of bacterial cultures and the metabolic activity of gram-negative and gram-positive bacteria was examined. Analysis of the vitamin C and B-group vitamins content in these supplements was also conducted. The test results showed that the examined supplements are a rich source of phenolic compounds, chlorophyll, antioxidants, and vitamin C. Furthermore, it was found that these products can be used as prebiotics in the diet. Based on the conducted tests, it was concluded that "greens" food supplements offer a wide range of health benefits and can be considered a useful contribution to a balanced diet and a healthy lifestyle. Practically, in all conducted tests, the products with a high matcha content achieved the best results, making this ingredient a key component for creating quality dietary supplements from plant-based ingredients.
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Bioactive compounds in cruciferous vegetables
KOVAČIKOVÁ, Karolína
This diploma thesis deals with bioactive compounds in cruciferous vegetables (Brassicaceae). The thesis aimed to determine the content of phenolic compounds, chlorophyll A, chlorophyll A+B, carotenoids and also vitamin C, in selected species of cruciferous vegetables: Brussel sprouts (Brassica oleracea var. gemmifera), Fodder Kale (Brassica oleracea var. acephala), Curly Kale (Brassica oleracea var. sabellica) and Ornamental Cabbage (Brassica oleracea var. capitata). The highest amount of chlorophyll A was represented in the sample of ornamental red cabbage, variety Pigeon Victoria F1. The highest content of chlorophyll B, chlorophyll A+B, carotenoids and also vitamin C was determined in curly green kale, a variety Tuscan. The highest amount of phenolic compounds was measured in curly red kale, variety Scarlet.
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Isolation and characterization of beta-glucans of natural origin
Ratsilouskaya, Lizaveta ; Hoová, Julie (referee) ; Márová, Ivana (advisor)
The bachelor thesis deals with the characterization of natural beta-glucans and other active substances isolated from macroalgae and yeasts. The used macroalgae samples differ in the pigment, origin and method of algae processing. The theoretical part focuses on seaweed and yeast species, beta-glucans, their sources and biological effects, other biologically active substances (such as polyphenols and antioxidants) and finally on methods for determining these biologically active substances. In the practical part, samples of selected macroalgae were analyzed, namely samples of Arame, Nori, Kombu, Wakame, Hijiki and Spaghetti. Aqueous, ethanol and acetone extracts of these algae were prepared in this work. The aqueous extracts were used for spectrophotometric determination of phenolic substances, flavonoids and antioxidant activity by the ABTS method. Furthermore, ethanol and acetone extracts of said macroalgae were used to determine total chlorophyll and carotenoid content spectrophotometric. The work also focused on beta-glucan content, analyzing macroalgae and yeast R. toruloides. Arame and Nori algae and R. toruloides were high in beta-glucans. However, beta-glucans were very low in other macroalgae.
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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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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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