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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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Influence of storage on the microbial composition of French Saint-nectaire cheese
Šislerová, Lucie ; Mikulíková, Renata (referee) ; Brázda, Václav (advisor)
The aim of my work is the comparison of microbial composition between farmtype and dairytype of Saint-nectaire cheese and the influence of storage time and temperature on the development of microbial composition, content of fatty acids and aromatic substances. Selected microorganisms were identified by RT-PCR. In addition, Penicillium roqueforti and fuscoglaucum have been identified in the Saint-nectaire farm type compared to the dairy type. In both types of cheese, the highest amount of selected microorganisms was detected in fresh cheese. When stored at 20 °C, an increase over fresh cheese occurred in the following microorganisms: Streptococcus thermophilus, Lactobacillus bulgaricus, Cladosporium herbarum and Penicillium commune and camemberti, and the presence of contaminants and pathogens was noted. After one week of storage at 20 °C, they were Micrococcus luteus, Salmonella enterica and Staphylococcus aureus, and after another two weeks of storage, Listeria monocytogenes was identified. The fatty acid and volatile compounds were compared for five samples: fresh cheese, cheese stored in the refrigerator for one week and three weeks and cheese stored at 20 °C for one week and three weeks. The content of bound and free fatty acids was measured, both by GC-FID. The content of bound fatty acids was comparable in all measured samples. The highest content of free fatty acids was in the cheese after three weeks of storage at 20 °C. The most common fatty acid is palmitic acid. Volatiles were determined by HS-SPME-GC-MS. The most volatiles were identified in the cheese after three weeks at 20 °C and in the cheese after one week in the refrigerator. The most represented groups were alcohols, ketones and acids.
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Assessment of fatty acids in selected type of cheese
Chmelařová, Adéla ; Sůkalová, Kateřina (referee) ; Vítová, Eva (advisor)
This bachelor thesis is focused on identification and quantification of free and bound fatty acids in commercially available white mold cheeses: Hermelín, Kamadet and Olmín, using gass chromatography withflame ionization detection. Theoretical part of the thesis is dealing with the classification of cheeses with the main attention to white mold cheeses. In a following part cheese production technology is described, lipids and fatty acids are characterised including the possible methods for their assessment, mainly gass chromatography. Experimental part the contents of free and bound fatty acids in selected samples of white mould cheeses were compared. The method in accordance with ČSN EN ISO 1735:2005 was selected for lipid extraction. Fatty acids were identified as methylesters using acid esterification with methanolic solution of bortrifluorid as a catalyst. In total 21 free and bound fatty acids were detected in samples.
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Production of lipid substances by Metschnikowia yeasts grown on some waste substrates
Gonová, Dominika ; Márová, Ivana (referee) ; Němcová, Andrea (advisor)
Oleaginous yeasts posses the ability to accumulate increased amount of lipids under appropriate conditions. These microbial lipids vary in the composition of fatty acids which results in their wide application in the biotechnological industry. This master thesis focuses on the lipid production and fatty acids composition from waste substrates by the yeasts Metschnikowia depending on various cultivation conditions. The influence of temperature, the ratio of carbon and nitrogen in medium, and the concentration of different carbon sources was studied. The cheap and easy available waste substrates as glycerol and animal fat were used for the cultivation. The production characteristics of the yeasts were monitored by various technique including gas chromatography, Raman spectroscopy and fluorescence microscopy FLIM. Moreover, the partial optimalization of the pulse field gel electrophoresis was applied in order to characterize the karyotype of the yeasts Metschnikowia. All the studied strains were able to use the waste substrates and at the same time to produce lipids. The amount of lipids and mainly their compositions vary depending on the yeast strain and on the culture conditions. Nevertheless, the ability of the yeasts to produce significant amount of unsaturated fatty acids by manipulation of culture conditions was proved. The maximum lipid yield was achieved by M. pulcherrima 149 on glycerol medium and by M. andauensis 129 on medium containing waste animal fat.
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Analysis of Organic Markers for Identification of Sources of Atmospheric Aerosols
Křůmal, Kamil ; Chýlková, Jaromíra (referee) ; Vávrová, Milada (referee) ; Smolík,, Jiří (referee) ; Večeřa, Zbyněk (advisor)
In this work the organic markers that serve for identification of sources of aerosols are monitored. Theoretic part deals with detailed survey of organic markers emitted from the most significant sources of atmospheric aerosols (biomass combustion, combustion of fossil fuels and traffic) as well as with sampling of aerosols and analysis of organic markers by analytical techniques. Monosaccharide anhydrides (emissions from biomass combustion) and polyaromatic hydrocarbons (emissions from traffic and incomplete combustion) were observed especially. Hopanes and steranes (traffic, coal combustion) and fatty acids (cooking) were next groups of monitored organic markers. Markers were studied mainly in size fraction PM1 because this fraction of aerosols is the most harmful to human health. Aerosols were sampled in two seasons (winter and summer) in two towns in 2009. Higher concentrations of aerosols and organic compounds were found in winter season, which resulted from increased combustion of biomass, coal and other organic material while traffic was the most significant source of aerosols in summer.
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The assessment of fatty acids in cheeses
Rajnochová, Veronika ; Omelková, Jiřina (referee) ; Vítová, Eva (advisor)
This bachelor thesis deals with the determination of fatty acids in natural Edam cheese. The theoretical part briefly characterize the natural Edam cheese, main attention is paid to lipids, fatty acids and the possibility of their determination by gas chromatography. In the experimental part the content of fatty acids in the model samples of natural Edam cheese produced at Tomas Bata University in Zlín was determined. The method according to ISO 1735 was chosen for extraction of lipids from the samples , the method according to ISO 5509 using methanol solution of potassium hydroxide was chosen for the esterification of fatty acids ,. The resulting methyl esters were determined by gas chromatography with FID detection.
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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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Application of microbial oils in cosmetics
Reichertová, Klára ; Uhlířová, Renata (referee) ; Němcová, Andrea (advisor)
This bachelor thesis is focused on the application of microbial oil in a cosmetic product. Eight strains of yeasts of the genus Metschnikowia were examined, namely Metschnikowia pulcherrima 145, Metschnikowia pulcherrima 147, Metschnikowia pulcherrima 149, Metschnikowia andauensis 129, Metschnikowia andauensis 1241, Metschnikowia sinensis 1244, Metschnikowia zizyphicola 1247 and Metschnikowia shanxiensis 1250 for production of microbial oil. Substrates made of technical hemp (hemp flour, hydrolyzate and a mixture of leaves and flowers) were used for cultivation. The cultivation was performed at reduced temperature with the advantage of lipid production. The composition and ratio of fatty acids were determined by gas chromatography According to these resulst was choosen the best lipid producer and the most abundant substrate. This was the strain Metschnikowia zizyphicola 1247 and the substrate of hemp flour. At the end of the practical part was prepared a cream, into which the microbial oil was mixed. Finally, an evaluation of the oil with regard to its use in cosmetics and a comparison with vegetable oil with the same fatty acid profile are given.
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Study of production properties of Metschnikowia yeasts
Chadimová, Markéta ; Szotkowski, Martin (referee) ; Němcová, Andrea (advisor)
Metschnikowia yeasts are able to produce under different conditions different amounts of lipids, which have remarkable uses in biotechnology and industry. This bachelor thesis is focused on the study of cultivation conditions under which yeasts produce the most lipids and also deals with which fatty acids these triacylglycerols are composed of. The influence of cultivation conditions on the amount of biomass is also monitored. Five yeast strains were examined, namely M. pulcherrima 145, M. pulcherrima 147, M. pulcherrima 149, M. andauensis 129 and M. chrysoperlae 1158. Cultivation media with different C/N ratios, containing glucose or cheap waste substrates (glycerol, coffee and waste fat) were used for cultivation. The cultivations were performed at several temperatures and then the amount of grown biomass was determined, and the composition and ratio of fatty acids were determined by gas chromatography. As yeast that produced the most biomass per time was determined the yeast M. chrysoperlae 1158, which after 336 hours of growth at 15 °C was able to produce 10,66 g/l of biomass on a medium with a ratio of C/N = 100. The highest amount of lipids was obtained with yeast M. andauensis 129 at 8 °C on medium with a ratio of C/N = 100 (21,57 % lipids in dry matter). If biomass production is also taken into account, the best results are obtained by the yeast M. chrysoperlae 1158 at a temperature of 11 ° C on a medium with a ratio of C/N = 100 with a biomass production of 10,15 g/l and 19,58 % lipids in dry matter. This yeast was therefore further cultivated on waste substrates.
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Profile of fatty acids in Edam type cheese
Babištová, Lucie ; Zemanová, Jana (referee) ; Vítová, Eva (advisor)
This bachelros thesis is focused on identification and qualification of free and bound fatty acids in edam type cheese. The samples were produced in Univarsity of Tomáš Baťa in Zlín. The theorytical part characterizes the cheese, their classification, composition and production process. This part also contains description of fats, fatty acids and gas chromatography with flame ionization detector. In the experimental part the contents of free and bound fatty acids in the model samples, produced using combination of microbial cultures are determined and compared. The method described in EN ISO 1735:2005 was used for extraction of lipids from the samples. Fatty acids were converted to methylesters by acidic esterification with methanolic solution of bortrifluoride as a catalyst. Then the fatty acids were assessed using the gas chromatography with flame ionization detector. The total number of 17 fatty acids in both free and bound form were assessed in samples. Unequivocal influence of addition of thermophilic culters on the contents of fatty acids cannot be proven.
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