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Production of lipolytic enzymes by yeasts
Bradáčová, Kristína ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on controlled production of lipolytic enzymes, bioactive substances and lipids by carotenogenic yeasts. Theoretical part deals with characterization of lipolytic enzymes, carotenoids, lipids and their properties, possibility of production and application. In experimental part the enzymes, carotenoids and lipids were produced by red yeasts Rhodotorula mucilaginosa, Cystofilobasidium macerans and Sporidiobolus salmonicolor by submerged cultivation in mineral medium with different additions: glucose, glycerol, fat, fat with glucose, fat with polysorbate 80, fat with glycerol, fat with polyethylene glycol, fat with higher and lower addition of palmitic acid, enzymatic fat hydrolysate, acidic hydrolysate a basic hydrolysate. The activity of extracellular lipase was monitored in medium after 96-hour cultivation. Concentration of -carotene, total carotenoids, ergosterol and ubiquinone was determined by HPLC, concentration of fatty acids and amount of fat by GC. Production had differed depending on used yeasts and substrate. As the best producer of carotenoids Cystofilobasidium macerans was found, ergosterol was highly produced by Sporidiobolus salmonicolor. The production of ubiquinone was almost equivalent in all yeasts and lipolytic activity was the highest in Sporidiobolus salmonicolor. The patricular medium sample with high lipolytic activity was further separated and analysed by ultrafiltration and PAGE-SDS electrophoresis. This diploma thesis was done within the international project ,,LipoFungi“.
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Study of carotenogenic yeasts doring growth by using advanced instrumental techniques
Vaněk, Martin ; Breierová, Emília (referee) ; Márová, Ivana (advisor)
This work is dealing with application of advanced fluorescence techniques for gaining knowledge about culture development during fermentation of red yeasts. Flow cytometry was used for auto-fluorescence measurement a carotenoids quantitation. It was resolved that while carotenoids are stored mainly in membranes the technique was feasible. If red yeast starts to accumulate carotenoids into lipid bodies mainly throughout the course of stationary phase, then the method starts to fail. Flow cytometric method using cell size measurement and light scatter for lipid quantitation was proved as applicable, too. However, it works only if cells are not starved. Individual calibration for each species is needed for elimination inter-species variations of intracellular structures. Fluorescence lifetime imaging microscopy was also used for studying of red yeast. Inherent ability to resolve different fluorescent species of the same molecule, which arise due to different molecular environment, helps with quantitation of cellular lipidic structures changes through the course of fermentation. Increase in the levels of carotenoids and/or rigidity of membranes was found as mechanism of protection during metabolic shifts, when intracellular content is vulnerable to damage.
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Production of lipolytic enzymes by yeasts
Bradáčová, Kristína ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on controlled production of lipolytic enzymes, bioactive substances and lipids by carotenogenic yeasts. Theoretical part deals with characterization of lipolytic enzymes, carotenoids, lipids and their properties, possibility of production and application. In experimental part the enzymes, carotenoids and lipids were produced by red yeasts Rhodotorula mucilaginosa, Cystofilobasidium macerans and Sporidiobolus salmonicolor by submerged cultivation in mineral medium with different additions: glucose, glycerol, fat, fat with glucose, fat with polysorbate 80, fat with glycerol, fat with polyethylene glycol, fat with higher and lower addition of palmitic acid, enzymatic fat hydrolysate, acidic hydrolysate a basic hydrolysate. The activity of extracellular lipase was monitored in medium after 96-hour cultivation. Concentration of -carotene, total carotenoids, ergosterol and ubiquinone was determined by HPLC, concentration of fatty acids and amount of fat by GC. Production had differed depending on used yeasts and substrate. As the best producer of carotenoids Cystofilobasidium macerans was found, ergosterol was highly produced by Sporidiobolus salmonicolor. The production of ubiquinone was almost equivalent in all yeasts and lipolytic activity was the highest in Sporidiobolus salmonicolor. The patricular medium sample with high lipolytic activity was further separated and analysed by ultrafiltration and PAGE-SDS electrophoresis. This diploma thesis was done within the international project ,,LipoFungi“.
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Study of carotenogenic yeasts doring growth by using advanced instrumental techniques
Vaněk, Martin ; Breierová, Emília (referee) ; Márová, Ivana (advisor)
This work is dealing with application of advanced fluorescence techniques for gaining knowledge about culture development during fermentation of red yeasts. Flow cytometry was used for auto-fluorescence measurement a carotenoids quantitation. It was resolved that while carotenoids are stored mainly in membranes the technique was feasible. If red yeast starts to accumulate carotenoids into lipid bodies mainly throughout the course of stationary phase, then the method starts to fail. Flow cytometric method using cell size measurement and light scatter for lipid quantitation was proved as applicable, too. However, it works only if cells are not starved. Individual calibration for each species is needed for elimination inter-species variations of intracellular structures. Fluorescence lifetime imaging microscopy was also used for studying of red yeast. Inherent ability to resolve different fluorescent species of the same molecule, which arise due to different molecular environment, helps with quantitation of cellular lipidic structures changes through the course of fermentation. Increase in the levels of carotenoids and/or rigidity of membranes was found as mechanism of protection during metabolic shifts, when intracellular content is vulnerable to damage.
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