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Use of third-generation biofuels for energy purposes
Janská, Barbora ; Köbölová, Klaudia (referee) ; Zlevorová, Tereza (advisor)
Algae-based biofuel is currently a very attractive source for future use. This bachelor's thesis covers the whole process of fuel production, from cultivation to the product itself. The first chapter covers the classification of biofuels and attitudes towards algae processing in the Czech Republic and abroad. Next, there are methods of cultivation. The third chapter describes ways of harvest, separation and individual processes of third-generation biofuel production. This work, among other things, includes a comparison of the yield of biofuels from commonly used energetic feedstock with algae.
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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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Photobioreactor for cultivating Spirulina
Tomandl, Jiří ; Naď, Martin (referee) ; Lošák, Pavel (advisor)
This bachelor thesis addresses the issue of microalgae cultivation, specifically focusing on Spirulina, with the aim of designing a device for its efficient cultivation to produce fresh biomass intended for consumption. Spirulina is characterized by its high content of proteins, minerals, and antioxidants, making it known as a dietary supplement with numerous benefits. The thesis includes the design of a photobioreactor for home cultivation of Spirulina, considering efficiency, simplicity, and economic affordability. The work includes literature review, technical documentation, prototype construction, economic evaluation of the device and operational costs. The proposed photobioreactor enables the production of fresh spirulina at low cost, thus contributing to the wider availability of fresh spirulina to the general consumer. The proposed solution has the potential to increase awareness of the ecological and nutritional benefits of spirulina and to promote its use in households.
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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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Development of cereal products for specific nutrition with the addition of legumes, algae and yeasts
Pavlištíková, Nela ; Mikulíková, Renata (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on the development of cereal products for special nutrition with the addition of legumes, algae and yeast. In the theoretical part, expert knowledge about gluten-free cereals, their chemical composition, gluten and food fortification is developed. Then an overview of the legumes, algae and yeasts tested in this work was elaborated. As a part of the literature review, emphasis was placed on the chemical composition of the analysed products. In the experimental part, the characterization of selected gluten-free cereals and legumes was carried out. The tested cereals were buckwheat, quinoa and gluten-free oatmeal. Pea, red lentil and Beluga black lentil were selected from among legumes. Furthermore, various types of algae and yeast extracts were prepared, which were subsequently optimized. Algae of the genera Dulse, Chlorella and Spirulina were selected for enrichment of pseudocereals. Dried baker's yeast and Saccharomyces cerevisiae were chosen as yeast representatives. Phenolics, flavonoids, antioxidant activity, carbohydrates, proteins, fatty acids, lipids and lipophilic pigments were determined in gluten-free cereals and legumes. The content of -glucans and gluten were determined for in cereals as well. Some content of phenolic substances, flavonoids, antioxidants, total fatty acids, lipophilic substances, pigments and -glucans were found in extracts from algae and yeast. Selected samples were also subjected to antimicrobial and cytotoxicity tests. Finally, mixed cereal products were prepared from selected gluten-free cereals, legumes, selected algae and yeast extracts and algae biomass. Extracts were selected based on obtained results and subjected to MTT cytotoxicity tests. It was found that the addition of pea, extracts from algae and yeast or the algae biomass itself increased the protein content of the prepared mixtures. Furthermore, in hexane:ethanol extracts from Chlorella and Spirulina or their biomass, the amount of antioxidants has been increased. The obtained results show that the combination of cereals with addition of algae and yeast extracts is suitable for increasing the protein content in gluten-free products. It was also found that selected microalgae and yeast have the potential to enrich gluten-free products with bioactive substances, when using biomass or extracts produced from them.
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Preparation of Cosmetic Product Based on Microbial Extracts
Reichertová, Klára ; Trachtová, Štěpánka (referee) ; Hudečková, Helena (advisor)
This thesis is focused on the preparation of a cosmetic product based on microbial extracts. The thesis is divided into two main parts, theoretical and practical. The theoretical part describes the types of cultured microorganisms, microbial metabolites, legislation and safety of cosmetic products, composition of human skin and last but not least the applied analyses. The experimental part deals with the use of waste products of the food industry, specifically coffee grounds as a substrate for culture media. Furthermore, the cultivation is studied with a focus on the gain of metabolites useful in the cosmetic industry, the analysis of these metabolites by GC/FID and HPLC/PDA. The work addresses the preparation of microbial extracts, their testing including determination of polyphenol and flavonoid content and characterization of antioxidant activity and antimicrobial activity tested on bacterial cultures of Esterichia coli and Staphylococus epidermidis. The application of the analysed extracts and their application to the final product is also addressed. The last chapter discussed in this thesis to test the final product using Visioscope PC–35, instrument and performing sensory analysis. The cultured strains were Phaffia rhodozyma CCY 77-1-1, Cystophilobasidium macerans CCY 10-1-2, Rhodosporidium toruloides CCY 062-002-004 Chlorella vulgaris CCALA 924. The biomass obtained by cocultivation of Phaffia rhodozyma CCY 77-1-1 and Chlorella vulgaris CCALA 924 as well as the biomass of these two microorganisms cultured separately were used for the preparation of microbial extracts.
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Inner geometry optimization of flat-panel photobioreactor
Hlaváč, Ivan ; Babička Fialová, Dominika (referee) ; Rebej, Miroslav (advisor)
This master thesis focus on optimatization of flat-panel photobioreactor. The optimatization was performed using CFD models and Design of experiement. The CFD model used for the optimatizaion was before performing the experiment validated with real experiment data. Hydrodynamic parameters affecting microalgae yield were monitored during CFD calculations. They were: gas holdup, gas velocity, turbulent kinetic energy, dead zone ratio. interfacial area and shear stress.The photobioreactor with a stirrer and with vertical baffles, which were selected based on research, were compared. The higher values of hydrodynamic parameters were reached with a stirrer. Baffels were evaluated as more suitable for microalgae, which are more sensitive to shear stress.
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Glycerolipids and carotenoids in microalgae: the implications in ecophysiology and applied phycology
Střížek, Antonín ; Nedbalová, Linda (advisor) ; Brányiková, Irena (referee) ; Barreira, Luísa (referee)
Lipids are basic biomolecules found in all organisms. They have a key function as structural molecules forming cell membranes, and, in the form of fats and oils, energy is also stored. There are a huge number of lipid types that have other functions, for example, in cell signaling, enzyme support, protection against stress, and others. Microscopic algae are the main primary producers in both freshwater and marine ecosystems. Therefore, algal biosynthesis has a fundamental effect on the trophic networks of aquatic ecosystems and ultimately on humans. The environment affects the ecophysiology of algae, which is reflected in their biochemical composition, i.e. in the composition of their lipids. This work is focused on two groups of lipids, namely glycerolipids, which consist of fatty acids, and carotenoids, which are photosynthetic pigments with antioxidant and photoprotective properties. In these groups of lipids, the target substances were further selected, namely polyunsaturated fatty acids and the carotenoid fucoxanthin belonging to xanthophylls. These substances are important not only in the ecophysiology of algae, but they are valuable substances that have positive effects on the human organism and, with the help of optimized cultivation, could be obtained from algae for industrial 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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