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Issues of the algae Chlorella production in flow bioreactors
Jankovičová, Kristína ; Lukavský,, Jaromír (referee) ; Svěrák, Tomáš (advisor)
Microalgae invite the attention of scientists due to their unique properties, including their quick growth, accumulation of lipids and other valuable substances, fixation of carbon dioxide and treatment of wastewater. This master´s thesis is focused on the study of microalgae. The main goal is to understand and describe the process of microalgae cultivation, in order to optimize it. The theoretical part of this thesis deals with microalgae (mainly Chlorella sp.) characterization, its practical use and cultivation optimization in order to obtain the highest concentration of biomass. The experimental part is divided into three tasks. Aim of the first task was the comparison of the course of autotrophic and heterotrophic cultivation of various strains of Chlorella and Coccomyxa microalgae, using three different cultivation media – synthetic medium for chlorella cultivation and natural fertilizer, Florium, used in two different concentrations (diluted 50 and 20 times). The highest Chlorella sp. biomass concentration of 7,10 g/l was achieved in the synthetic heterotrophic medium. Second task was focused on monitoring of the growth of algae Coccomyxa and Chlorella strain C1A, with respect to temperature and light intensity, using various combinations of these two important growth factors. Chlorella achieved its highest concentration of 11,46 g/l when grown at temperature of 33,5 °C and light intensity of 320 µE.m2.s1. The third and final task was to observe the growth of Dictiosphaerium chlerelloides microalgae on a flat cascade bioreactor. The experiment led to the discovery that these algae were able to grow at temperatures of around 10 °C, at which many well-known commercial algae, such as Chlorella sp. or Arthrospina sp., simply wouldn’t grow.
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Raman microspectroscopy of living cells and biological tissues
Moudříková, Šárka ; Mojzeš, Peter (advisor) ; Matthäus, Christian (referee) ; Samek, Ota (referee)
Title: Raman microspectroscopy of living cells and biological tissues Author: Šárka Moudříková Department / Institute: Institute of Physics of Charles University Supervisor of the doctoral thesis: doc. RNDr. Peter Mojzeš, CSc., Institute of Physics of Charles University Abstract: Raman microscopy combines Raman spectroscopy with optical confocal microscopy and thus provides information on chemical composition of a sample with a µm3 resolution. In this thesis, Raman microscopy has been used to study microalgae-unicellular photosynthetic organisms that are greatly relevant for the Earth's environment as well as for biotechnological applications. Raman microscopy of photosynthetic organisms struggles with a highly intensive background of the spectra, which is formed by fluorescence of cellular photosynthetic apparatus. In this thesis, we have developed a fast and reliable photobleaching method that suppresses the unwanted background; this method has enabled us to study intracellular distribution of algal biomolecules such as proteins, starch, lipids and polyphosphate. We have investigated an evolution of these structures during a cell cycle of a model microalga Desmodesmus quadricauda. Next, we have developed a method for quantitative analysis of polyphosphate in a cellular culture of a microalga Chlorella...
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Microcrystalline inclusions in microalgae studied via Raman microscopy
Suja, Matyáš ; Mojzeš, Peter (advisor) ; Šloufová, Ivana (referee)
Many freshwater, terrestrial or marine microalgae contain various microcrystalline inclusions that they use in their life cycle. However, the identification of the molecular composition of these inclusions via many physical or chemical methods is often very difficult and susceptible to many measurement errors. Therefore, the chemical composition of these microcrystals in many microalgae has not been determined at all or may be incorrect. One of the high precision methods capable of determining the composition of microcrystalline bodies within microalgae is Raman confocal microscopy. This very promising method of optical vibrational spectroscopy allows rapid and non-destructive molecular analysis of objects. Raman microscopy does not require chemical extraction, modification or other color marking or staining of the sample. Therefore, it can directly measure living cells at various stages of their natural development. The chemical composition of the sample is then characterized by its corresponding Raman vibrational spectrum. The aim of this diploma thesis is to determine the presence of microcrystals in different species of microalgae, study the conditions of their occurrence and identify their chemical composition via Raman microscopy.
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Experimental Report, Period 9-12/2017, Project: Electrocoagulation Unit for Microalgal Biomass Separation.
Brányiková, Irena ; Vojtěchovský, R. ; Čermáková, Lenka
Production of microalgae in the world is increasing every year, but their use in food, cosmetics, feed and biofuel production is still limited by the high production price and high energy input. The substantial part of the energy costs lies in the separation of algal biomass from the medium, which is most often performed on plate centrifuges. The harvest concentration of algal suspensions in most cultivation systems ranges between just 1-5 g/L. Therefore, to obtain 1 kg of dry biomass, it is necessary to remove 200 to 1000 liters of water (by centrifuging and then drying). This amount of water and thus the energy input can be reduced via flocculation added as a pre-step prior to centrifugation. Electrofloculation is type of floculation, where the flocculant is directly formed by dissolving the electrodes. Suitable electrode material and parameter set enable obtaining of biomass, which is not contaminated by chemical flocculants and meets requirements for food stuff. The main objective of this project is to develop a continuous electroflocculation device suitable for these purposes.\n
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Experimental Plan for the Project: Electrocoagulation Unit for Microalgal Biomass Separation.
Brányiková, Irena ; Vojtěchovský, R. ; Čermáková, Lenka
Electrofloculation (electrocoagulation) of microalgae is a highly complex process involving a number of very complex transport, electrochemical, hydrodynamic and surface phenomena. The description of this process at the level of single mechanisms involved is too complicated and experimentally demanding, fortunately it is not absolutely necessary for the practical application. The electrofloculation was therefore approached by an engineering method that identified the criteria (range) of the desired variables and the main factors that affect them. For these factors, partial factorial experimental plans were designed.
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Photosynthesis Monitoring in Microalgae Mass Cultures
MALAPASCUA, Jose Romel
This Ph.D. thesis deals with principles of microalgae cultivation in laboratory as well as outdoor aquacultures (Chapter 1) using various cultivation systems and photobioreactors (Chapter 2). Case studies illustrate the main research topic as to correlate changes in growth rate with variation of photosynthetic activity, physiological features and biomass composition (Chapter 3). Special attention was paid to elaboration of protocols of chlorophyll a fluorescence techniques for monitoring the physiology and photosynthetic performance of microalgae mass cultures maintained under various growth conditions (Chapter 4).
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Production of beta-glucans by some yeasts and algae
Veselá, Markéta ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
Several yeast strains and microalgae were selected for this diploma thesis. -glucans, lipids, carotenoids, ergosterol and coenzyme Q were determined in selected producers, and the cultivation conditions for yeast strains were optimized to gain enhanced production of -glucans. Microalgae cultivations were carried out according to the instructions of the Collection of Autotrophic organisms (CCALA). Selected microalge strains include Desmodesmus acutus, Dunaliella salina, Arthrospira maxima and Cyanothece sp. Selected yeast species include Rhodotorula glutinis, Cystofilobasidium macerans and Sporidiobolus metaroseus. Edible yeast Saccharomyces cerevisiae was cultivated to compare with other yeast strains because of it's verified production of -glucans. -glucans were then determined by the enzymatic kit K-YBGL Megazyme, carotenoids, ergosterol and coenzyme Q were analyzed by HPLC/PDA and fatty acids were analyzed by GC/FID. The best producer of yeast -glucans was R. glutinis and S. metaroseus, and the best conditions for the production of -glucans and other metabolites was the C/N ratio of 70. Within the microalgae species, only -glucan production was observed, the best producer was D. acutus.
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