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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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Use of algae extracts in cosmetics
Plášková, Anna ; Rapta, Marek (referee) ; Márová, Ivana (advisor)
This thesis is focused on a preparation of extracts from selected species of algal and cyanobacterial strains, their characterization, a cytotoxicity testing and a use in cosmetic products. The theoretical part contains the review of a taxonomic classification and parameters of algae and cyanobacteria and basic information about used organisms. There is a description of the most significant factors influencing the algae cultivation and production of biomass. Further, active substances of algae and cyanobacteria, which could be used in cosmetic products as UV protective substances, were described. An overview of extraction techniques, encapsulation of active substance into liposomes and particles characterization, antioxidant activity analysis, and cytotoxicity tests is given too. In experimental part, antioxidant activity of algal extracts and chlorophyll a and carotenoid content were determined spectrophotometrically. The long-term stability of extracts was monitored for three weeks. Liposomes were prepared by sonification and encapsulation activity was analysed. The Dynamic Light Scattering method (DLS) was used for analysis of polydispersity and size of liposomes. Colloid stability of particles was determined by zeta potential. Cytotoxicity tests were performed using MTT assay. The prepared extracts, particles and lyophilized biomass of algal and cyanobacterial strain were further used as active substances in the formulation of cosmetic products (type o/w). These creams were tested on human skin.
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The antimicrobial effects of plant extracts against yeast skin mycoses
Posztósová, Gyöngyi ; Rapta, Marek (referee) ; Němcová, Andrea (advisor)
Superficial cutaneous mycoses are relatively widespread and affect more and more people. Currently are used drugs as ketoconazole, fluconazole and others to treat mycoses. Pathogens occasionally become resistant to these drugs. Medicinal plants have a long history in alternative medicine and they could be a good solution. This bachelor thesis deals with the study of antifungal activity of selected plants. Were prepared ethanol extracts of basil, betony, eucalyptus, turmeric, geranium, oregano and ginseng. The theoretical part of thesis contains a review of the most frequently occurring dermatomycoses. It describes plants as sources of natural substances with antimicrobial effect and the content of selected active substances. The experimental part is focused on the analysis of plant extracts. Was determined the content of total polyphenols, flavonoids and antioxidants. The antimicrobial activity was monitored against yeast Candida glabrata and against G- and G+ bacteria, specifically Escherichia coli and Micrococcus luteus. Finally, the cosmetic products with the addition of plant extract were prepared and tested against mycoses.
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Regulation of production of lipids and lipid compounds in yeasts
Rapta, Marek ; Breierová, Emília (referee) ; Márová, Ivana (advisor)
Oleogenic yeasts under appropriate conditions produce and accumulate lipids and lipid-soluble metabolites in high amounts. This attribute is characteristic also for red yeasts that except lipids accumulate also carotenoids – natural pigments used in food industry and dietary supplements. The aim of this diploma thesis was designed as a comparative screening study of production properties of strains Cystofilobasidium capitatum, Rhodotorula glutinis, Sporobolomyces roseus and Sporobolomyces shibatanus. Choosen carbon sources were glucose and glycerol as waste by-product in biofuel industry. The best production properties were found in Cystofilobasidium capitatum and Rhodotorula glutinis. These two strains produced increased amounts of lipids as well as higher amounts of carotenoids. Strains were tested by FTIR spectroscopy that enables high-throughput, uncomplicated and accurate analysis.
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Comparison of growth and productivity of autotrophic algae and red yeasts
Kouřilová, Xenie ; Rapta, Marek (referee) ; Márová, Ivana (advisor)
The submitted bachelor thesis focuses on the comparison of growth and productivity of red yeasts Rhodotorula aurantiaca and Xanthophyllomyces dendrorhous and autotrophic algae Chlamydomonas reinhardtii and Chlorella vulgaris under different physical conditions. The theoretical part contains the characteristics of selected micro-organisms, stress factors caused by temperature, radiation, combination of aeration and radiation and osmotic stress. Furthermore, knowledge on metabolites and the possibilities of their analysis are mentioned. Physical stresses, namely 2%, 3%, 4% and 5% solution of sodium chloride, intense radiation, absence of lighting, 8°C and 30°C, were applied to selected strains in cultivation. Under these conditions, changes in production of carotenoids, fatty acids, ergosterol, ubiquinone and proteins were being observed. A significant inhibitive effect on all the above mentioned micro-organisms was brought about by the use of 5% solution NaCl. The highest production of metabolites with X. dendrorhous was discovered when 4% solution of NaCl was used. R. aurantiaca demonstrated higher substance utilization at 30°C. For the selected algae strains were the used stresses lethal. Within the cultivation process, the possibilities of co-cultivation of yeasts and algae were also tested, which will be the subject of further studies.
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Cultivation of carotenogenic yeasts on waste substrates usinf solid state fermentation
Rapta, Marek ; Petrik, Siniša (referee) ; Márová, Ivana (advisor)
Semi-solid fermentation is an eco - friendly technique more and more used for production of significant metabolites or enriched biomass at low entrance cost and low comsumption of water. The problem of this technique might be the right choice of microorganism able to grow and produce at low water activity. This work is a pilot study of three red yeast strains – Rhodotorula glutinis, Cystofilobasidium capitatum and Sporobomomyces roseus cultivated by semi-solid state fermentation (semi-SSF). Yeasts were cultivated in series of production media with gradual reduction of cultivation water content. Pasta and hydrolyzed pasta were used as source of sacharides, glucose served as the carbon source in control media. All studied strains we able to grow and produce observed lipidic metabolites also at low water contents. Production of carotenoids and sterols was higher in semi-solid media. Cystofilobasidium capitatum strain was identified as the best producer of carotenoids and biomass. This strain was cultivated on hydrolyzed pasta media with 40% water content. Semi-SSF seems to be an adequate technique for selection of strains having over-productive properties. Observed metabolites production in yeast cells can be optimized by choosing the appropriate production media and water activity.
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The antimicrobial effects of plant extracts against yeast skin mycoses
Posztósová, Gyöngyi ; Rapta, Marek (referee) ; Němcová, Andrea (advisor)
Superficial cutaneous mycoses are relatively widespread and affect more and more people. Currently are used drugs as ketoconazole, fluconazole and others to treat mycoses. Pathogens occasionally become resistant to these drugs. Medicinal plants have a long history in alternative medicine and they could be a good solution. This bachelor thesis deals with the study of antifungal activity of selected plants. Were prepared ethanol extracts of basil, betony, eucalyptus, turmeric, geranium, oregano and ginseng. The theoretical part of thesis contains a review of the most frequently occurring dermatomycoses. It describes plants as sources of natural substances with antimicrobial effect and the content of selected active substances. The experimental part is focused on the analysis of plant extracts. Was determined the content of total polyphenols, flavonoids and antioxidants. The antimicrobial activity was monitored against yeast Candida glabrata and against G- and G+ bacteria, specifically Escherichia coli and Micrococcus luteus. Finally, the cosmetic products with the addition of plant extract were prepared and tested against mycoses.
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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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Use of algae extracts in cosmetics
Plášková, Anna ; Rapta, Marek (referee) ; Márová, Ivana (advisor)
This thesis is focused on a preparation of extracts from selected species of algal and cyanobacterial strains, their characterization, a cytotoxicity testing and a use in cosmetic products. The theoretical part contains the review of a taxonomic classification and parameters of algae and cyanobacteria and basic information about used organisms. There is a description of the most significant factors influencing the algae cultivation and production of biomass. Further, active substances of algae and cyanobacteria, which could be used in cosmetic products as UV protective substances, were described. An overview of extraction techniques, encapsulation of active substance into liposomes and particles characterization, antioxidant activity analysis, and cytotoxicity tests is given too. In experimental part, antioxidant activity of algal extracts and chlorophyll a and carotenoid content were determined spectrophotometrically. The long-term stability of extracts was monitored for three weeks. Liposomes were prepared by sonification and encapsulation activity was analysed. The Dynamic Light Scattering method (DLS) was used for analysis of polydispersity and size of liposomes. Colloid stability of particles was determined by zeta potential. Cytotoxicity tests were performed using MTT assay. The prepared extracts, particles and lyophilized biomass of algal and cyanobacterial strain were further used as active substances in the formulation of cosmetic products (type o/w). These creams were tested on human skin.
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Comparison of growth and productivity of autotrophic algae and red yeasts
Kouřilová, Xenie ; Rapta, Marek (referee) ; Márová, Ivana (advisor)
The submitted bachelor thesis focuses on the comparison of growth and productivity of red yeasts Rhodotorula aurantiaca and Xanthophyllomyces dendrorhous and autotrophic algae Chlamydomonas reinhardtii and Chlorella vulgaris under different physical conditions. The theoretical part contains the characteristics of selected micro-organisms, stress factors caused by temperature, radiation, combination of aeration and radiation and osmotic stress. Furthermore, knowledge on metabolites and the possibilities of their analysis are mentioned. Physical stresses, namely 2%, 3%, 4% and 5% solution of sodium chloride, intense radiation, absence of lighting, 8°C and 30°C, were applied to selected strains in cultivation. Under these conditions, changes in production of carotenoids, fatty acids, ergosterol, ubiquinone and proteins were being observed. A significant inhibitive effect on all the above mentioned micro-organisms was brought about by the use of 5% solution NaCl. The highest production of metabolites with X. dendrorhous was discovered when 4% solution of NaCl was used. R. aurantiaca demonstrated higher substance utilization at 30°C. For the selected algae strains were the used stresses lethal. Within the cultivation process, the possibilities of co-cultivation of yeasts and algae were also tested, which will be the subject of further studies.
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