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Proteome and Metabolome Changes in Selected Organisms under Stress
Halienová, Andrea ; Kráčmar, Stanislav (referee) ; Čertík, Milan (referee) ; Šucman, Emanuel (referee) ; Márová, Ivana (advisor)
Living conditions of every organism are influenced by various factors at this time. Some of them have positive effect on organism, some negative. Basic condition for surviving is the ability to resist and adapt to changing metabolic and living conditions. Every single stress effect can lead to changes in metabolism but organisms have ability to develope sufficient mechanisms for stress response. Some of them are similar for all living organisms (enzyme production, endogenous primary stress metabolites) some of them are specific for certain organism or stress type. Cell stress response can be observed on different levels (proteomic, genomic, metabolomic). In proper conditions it can be used indrustrially. In this work, influences of various stress factors were studied. These factors were applied on selected organisms – carotenogenic yeast and plant materials. Yeast stress response was induced by osmotic and oxidation stress factors. Changes on proteomic level and in production of selected secondary metabolites were observed. Proteome was analyzed by 1D and 2D electrophoresis with subsequent analysis of proteins by mass spectrometry. Yeast strain Rhodotorula glutinis CCY 20-2-26 showed the best adaptation to stress factors, which was moreover accompanied by overproduction of carotenoids. This finding can be premise for next industrial production of carotenoids. In plant samples predominantly enzymes and metabolites involved in antioxidant response were studied.
Production, Characterization and Utilization of the Biomass from Various Sources
Gojkovic, Živan ; Vávrová, Milada (referee) ; Čertík, Milan (referee) ; Márová, Ivana (advisor)
Úprava biomasy je jedním z nejdůležitějších problémů v moderních přírodních vědách, protože je základní kategorií týkající se zemědělství, potravinářství, ekologie, zpracování odpadu a biotechnologie. Ať už živočišného, rostlinného nebo mikrobiálního původu, biomasa představuje obrovský zdroj surovin jako potravin, čistých chemikálií, bioaktivních molekul atd., jejichž izolace, charakterizace a formulace může vést k zajímavým novým produktům určeným pro lidskou spotřebu, nebo jako nový materiál v biomedicíně. Předložená studie byla zaměřena na výzkum dvou druhů biomasy - kuřecí kůže jako zdroje kolagenu t a biomasy mikrořasy Chlorella sorokiniana obohacené selenomethioninem (SeMet). V první části práce byl z kuřecí kůže izolován, identifikován a charakterizován kolagen typu I. Molekulární vlastnosti kuřecího kolagenu byly analyzovány a srovnány s jinými kolageny z živočišných kůží. Pro molekulární charakterizaci kolagenu byla použita viskosimetrie a ultrazvuková spektroskopie. Ultrazvukovou spektroskopií bylo zjištěno, že disagregace a zkapalňování hovězího kolagenu začíná při teplotě 40 °C, zatímco u kuřecího kolagenu začíná až při 50 °C. Viskosimetrie dále potvrdila vyšší tepelnou stabilitu kolagenu z kuřecí kůže, jeho denaturační teplota byla 50 °C, což je rovněž o deset stupňů více než u hovězího kolagenu. Kuřecí kolagen obsahuje dvakrát vyšší množství lysinu, což poskytuje tepelnou stabilitu kolagenu. Na základě získaných výsledků lze říci, že vzhledem ke své vysoké tepelné stabilitě a vhodnému aminokyselinovému složení, kuřecí kůže může být použita jako alternativní zdroj kolagenu typu I s aplikacemi v potravinářském průmyslu a biomedicíně. Druhá část práce byla zaměřena na obohacení biomasy zelené mikrořasy C. sorokiniana selenomethioninem. Experimentální část byla provedena v Laboratoři biotechnologie řas na Univerzitě Huelva ve Španělsku. Cílem první části experimentů bylo studovat vliv selenu na životaschopnost řas, morfologii buněk a akumulaci SeMet v biomase mikrořasy kultivované v dávkových kulturách. Subletální koncentrace Se v živném médiu, 40 mgL-1 (212 M), snížila rychlost růstu o 25 % ve srovnání s kontrolní kulturou. Hodnota EC50 45 mgL-1 (238,2 M) byla stanovena pro selenan. Ultrastrukturální studie ukazovaly na strukturální změny chloroplastu (granulární stroma, redukce thylakoid). Elektroforéza proteinů z biomasy mikrořasy ukazuje, že Se ovlivňuje expresi genu enzymu Rubisco. C. sorokiniana byla schopna akumulovat až 140 mgkg-1 SeMet během 120 h kultivace. Další část experimentální práce byla zaměřena na obohacování biomasy mikrořasy C. sorokiniana selenomethioninem během kontinuální kultivace s použitím 2,2 L bioreaktoru v kultivačním médiu s přídavkem koncentrace selenu v rozmezí od 5 do 50 mgL-1. C. sorokiniana rostla stejně ve všech testovaných koncentracích selenu kromě koncentrace 50 mgL1, která byla již po krátké době kultivace letální. Během kontinuální kultivace se 40 mgL-1 selenu, bylo získáno maximálně 246 gL-1 selenomethioninu denně. Výsledky ukazují, že kultivace v dávkových kulturách a dlouhodobá kontinuální kultivace mikrořasy C. sorokiniana pro získaní biomasy obohacené SeMet je možná pečlivým výběrem podmínek kultivace a subletálních koncentrací selenu v živném médiu.
Study of Activity of Enzyma and Low Molecular Weight Antioxidant Systems
Macuchová, Simona ; Kráčmar, Stanislav (referee) ; Čertík, Milan (referee) ; Márová, Ivana (advisor)
Oxidative processes play important role in cell physiology and pathology as well. Balance of these processes is supplied by cooperating antioxidative systems; function of antioxidant defense systems depens on high levels of antioxidants in organism. Presented work is focused on developement and optimization of methods for analysis of important enzyme and non-enzyme antioxidants as well as total antioxidant capacity of selected types of biological material. Extractions and analyses of vitamin E, carotenoids, superoxide dismutase, catalase, peroxidase and lipoxygenase in barley and malt were optimized. RP-HPLC and HPLC/ESI-MS were used for analysis of vitamin E, phenolic and carotenoid content, spectrophotometry was used for enzymes activity analysis. A new methods for catalase and lipoxygenase activities were developed and compared with direct UV methods. Superoxide dismutase activity was determined by commercial diagnostic kit. A colorimetric method was used for peroxidase activity determination. Some kinetic parameters of enzymes were provided too. Optimized methods were used in the analyses of antioxidants in plant material - in barley and malt - in sets of samples of 6 varieties cultivated in four different locations for two years. Content of individual antioxidants differed depending on the variety, but usually were not found significant differences in the levels, depending on growing location. Perhaps climatic conditions have the greatest influence on levels of low molecular weight and enzymatic antioxidants at the specific location; oxidation processes are influenced both the quantity of moisture, both by sunlight, which induces oxidative processes in cultivated plants. The activity of antioxidants in barley caryopses is rapidly increasing during the malting process; an elevated temperature and moistness first induces activation the enzyme systems including antioxidant. In caryopsis is metabolic activity increased during which we can expect an increased production of radicals; for this purpose can antioxidant systems be activated that protect cells from damage by oxidative stress. In the second part of work optimized methods were applied in two clinical trials focused on study of the influence of exogenous antioxidants intake on metabolic and antioxidant status in human organism. In the first clinical study influence of food supplement containing polyunsaturated fatty acids and vitamin E on metabolism of hyperlipidaemics was evaluated. After 3-month supplemenation a lipid profile was improved and serum antioxidant levels increased. The second experiment was focused on enzyme and non-enzyme antioxidant levels in healthy subjects after temporarily intake of specific foods rich in antioxidants. After two-month intake plasma phenolic substances were slightly increased. Total antioxidant capacity and activities of enzyme antioxidants were not affected. Results of both clinical exeriments showed that supplying of antioxidants in natural form or in the form of food supplements does not markedly affect metabolism of healthy subjects, while in patients with chronic diseases antioxidant supplementation can positively influence metabolic status. Results of this work showed that optimized methods are suitable for analyses of antioxidant status parameters and also for monitoring of exogenous antioxidant intake.
Bioproduction, Characterization and Application of Selected Biopolymers
Benešová, Pavla ; Pekař, Miloslav (referee) ; Čertík, Milan (referee) ; Márová, Ivana (advisor)
Proposed doctoral thesis deals with microbial production of biopolymers (polysaccharides and polyesters) using renewableble inexpensive resources as carbon and nitrogen source. At first, production of extracellular metabolites, mainly pullulan and poly-L-malic acid, by polymorphic microorganism Aureobasisium pullulans was studied. Further part of thesis was focused on production of bacterial biopolyesters polyhydroxyalkanoates (PHA). PHA are produced in the form of intracellular granules by various bacteria species. During the study of PHA production, sythesis of poly(3-hydroxybutyrate) and technologically significant copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) was investigated as well with regard to waste substrate utilization in biorafinery concept. Spent coffee ground seemed to be applicable waste in biorefinery proces. One of the coffee wastes used for PHA production was spent coffee ground hydrolysate which was converted to PHA by Burkholderia cepacia. Moreover, copolymer of 3HB and 3HV was accumulated when SCGH was used as a sole carbon source, no precursor had to be added. Another coffee waste, which was utillized by Cupriavidus necator H16, is represented by oil extracted from spent coffee grounds. Hydrolysis proces of waste substrates had to be optimized, to reach the highest possible saccharide concentration. Due to the hydrolysis process several toxic compounds can be formed, hence, influence of hydrolysis procesings on polyphenols content in hydrolysates was monitored. Waste substrates were also tested as potentional complex nitrogen source for PHA production. Hydrolysates of cheese whey and chicken feather were used as inexpensive complex nitrogen source for PHA production by C. necator, when waste frying oil was used as a carbon substrate. The finnal part of the thesis is dealing with possibilities how the PHA can be processed into atractive aplication forms. Liposomes with partial content of PHB had been prepared, moreover, for improving of antioxidant activity and antimicrobial effect the waste coffee oil was added. Micro-fibrous PHB materials were prepared for the purposes of water filtration. Higher filtration effectivity was observed when composite PHB fibrous material containing active charcoal or metal oxides was used. Important part of thesis is represented by study of degradation processes of prepared PHA-based aplication forms. Various microorganisms were tested on PHA depolymerases production. Biodegradability of PHA materials was tested in of composting conditions by standard composting test IS/ISO 20200. Changes in mechanical properties of polyurethan, where polyol was partialy replaced by PHB, were tested depending on the exposure of composting condition.
Production of Selected Yeast Metabolites Applicable to Food Supplements
Němcová, Andrea ; Čertík, Milan (referee) ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
Carotenoids are naturally occurring pigments of plants also produced in many bacteria, and fungi. They represent one of the widest group of natural antioxidants with significant biological effects and numerous of industrial applications. There is an increased interest in carotenoids as natural antioxidants for their ability to reduce chronic diseases, various pathological stages and aging. The area of their application concerns mainly food industry; however, they are used in chemical, pharmaceutical, and cosmetics industry as well. One possibility is study of potential of red yeasts that are able to convert various substrates into carotenoid pigments. In presented thesis carotenogenic yeast belonging to the genus Rhodotorula, Sporobolomyces and Cystofilobasidium were tested for ability to use of selected waste substrates and also random mutagenesis in order to increase the production of biomass and specific metabolites – carotenoids and other lipid-soluble substances. As alternative nutrient sources derived from waste substrates from agricultural and food production (rapeseed substrate, rice, wheat, apple fiber, pasta and lignocellusic materials) were tested. To selected production media extracellular hydrolytic enzymes or commercial enzymes degrading polysaccharide were added. All tested red yeast strains were able to utilize these substrates as the only carbon source and simultaneous produce carotenoid enriched biomass. In this work, characterization of carotenogenic yeast using molecular techniques was studied. For this usage, interspecific variables of strongly conserved sequences of genomic DNA, especially rDNA D1/D2 large ribosomal subunit and ITS1 and 5,8-ITS2 rDNA regions were amplified. These sequences were subjected analysed by DGGE method to compare differences of carotenogenic yeasts. Isolation procedure of the intact DNA were optimized for caryotypic yeast characterization by pulsed field gel electrophoresis (PFGE). The karyotype of tested yeasts contain visible differences between yeast species and genera.
Bioproduction, Characterization and Application of Selected Biopolymers
Benešová, Pavla ; Pekař, Miloslav (referee) ; Čertík, Milan (referee) ; Márová, Ivana (advisor)
Proposed doctoral thesis deals with microbial production of biopolymers (polysaccharides and polyesters) using renewableble inexpensive resources as carbon and nitrogen source. At first, production of extracellular metabolites, mainly pullulan and poly-L-malic acid, by polymorphic microorganism Aureobasisium pullulans was studied. Further part of thesis was focused on production of bacterial biopolyesters polyhydroxyalkanoates (PHA). PHA are produced in the form of intracellular granules by various bacteria species. During the study of PHA production, sythesis of poly(3-hydroxybutyrate) and technologically significant copolymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) was investigated as well with regard to waste substrate utilization in biorafinery concept. Spent coffee ground seemed to be applicable waste in biorefinery proces. One of the coffee wastes used for PHA production was spent coffee ground hydrolysate which was converted to PHA by Burkholderia cepacia. Moreover, copolymer of 3HB and 3HV was accumulated when SCGH was used as a sole carbon source, no precursor had to be added. Another coffee waste, which was utillized by Cupriavidus necator H16, is represented by oil extracted from spent coffee grounds. Hydrolysis proces of waste substrates had to be optimized, to reach the highest possible saccharide concentration. Due to the hydrolysis process several toxic compounds can be formed, hence, influence of hydrolysis procesings on polyphenols content in hydrolysates was monitored. Waste substrates were also tested as potentional complex nitrogen source for PHA production. Hydrolysates of cheese whey and chicken feather were used as inexpensive complex nitrogen source for PHA production by C. necator, when waste frying oil was used as a carbon substrate. The finnal part of the thesis is dealing with possibilities how the PHA can be processed into atractive aplication forms. Liposomes with partial content of PHB had been prepared, moreover, for improving of antioxidant activity and antimicrobial effect the waste coffee oil was added. Micro-fibrous PHB materials were prepared for the purposes of water filtration. Higher filtration effectivity was observed when composite PHB fibrous material containing active charcoal or metal oxides was used. Important part of thesis is represented by study of degradation processes of prepared PHA-based aplication forms. Various microorganisms were tested on PHA depolymerases production. Biodegradability of PHA materials was tested in of composting conditions by standard composting test IS/ISO 20200. Changes in mechanical properties of polyurethan, where polyol was partialy replaced by PHB, were tested depending on the exposure of composting condition.
Production of Selected Yeast Metabolites Applicable to Food Supplements
Němcová, Andrea ; Čertík, Milan (referee) ; Vávrová, Milada (referee) ; Márová, Ivana (advisor)
Carotenoids are naturally occurring pigments of plants also produced in many bacteria, and fungi. They represent one of the widest group of natural antioxidants with significant biological effects and numerous of industrial applications. There is an increased interest in carotenoids as natural antioxidants for their ability to reduce chronic diseases, various pathological stages and aging. The area of their application concerns mainly food industry; however, they are used in chemical, pharmaceutical, and cosmetics industry as well. One possibility is study of potential of red yeasts that are able to convert various substrates into carotenoid pigments. In presented thesis carotenogenic yeast belonging to the genus Rhodotorula, Sporobolomyces and Cystofilobasidium were tested for ability to use of selected waste substrates and also random mutagenesis in order to increase the production of biomass and specific metabolites – carotenoids and other lipid-soluble substances. As alternative nutrient sources derived from waste substrates from agricultural and food production (rapeseed substrate, rice, wheat, apple fiber, pasta and lignocellusic materials) were tested. To selected production media extracellular hydrolytic enzymes or commercial enzymes degrading polysaccharide were added. All tested red yeast strains were able to utilize these substrates as the only carbon source and simultaneous produce carotenoid enriched biomass. In this work, characterization of carotenogenic yeast using molecular techniques was studied. For this usage, interspecific variables of strongly conserved sequences of genomic DNA, especially rDNA D1/D2 large ribosomal subunit and ITS1 and 5,8-ITS2 rDNA regions were amplified. These sequences were subjected analysed by DGGE method to compare differences of carotenogenic yeasts. Isolation procedure of the intact DNA were optimized for caryotypic yeast characterization by pulsed field gel electrophoresis (PFGE). The karyotype of tested yeasts contain visible differences between yeast species and genera.
Production, Characterization and Utilization of the Biomass from Various Sources
Gojkovic, Živan ; Vávrová, Milada (referee) ; Čertík, Milan (referee) ; Márová, Ivana (advisor)
Úprava biomasy je jedním z nejdůležitějších problémů v moderních přírodních vědách, protože je základní kategorií týkající se zemědělství, potravinářství, ekologie, zpracování odpadu a biotechnologie. Ať už živočišného, rostlinného nebo mikrobiálního původu, biomasa představuje obrovský zdroj surovin jako potravin, čistých chemikálií, bioaktivních molekul atd., jejichž izolace, charakterizace a formulace může vést k zajímavým novým produktům určeným pro lidskou spotřebu, nebo jako nový materiál v biomedicíně. Předložená studie byla zaměřena na výzkum dvou druhů biomasy - kuřecí kůže jako zdroje kolagenu t a biomasy mikrořasy Chlorella sorokiniana obohacené selenomethioninem (SeMet). V první části práce byl z kuřecí kůže izolován, identifikován a charakterizován kolagen typu I. Molekulární vlastnosti kuřecího kolagenu byly analyzovány a srovnány s jinými kolageny z živočišných kůží. Pro molekulární charakterizaci kolagenu byla použita viskosimetrie a ultrazvuková spektroskopie. Ultrazvukovou spektroskopií bylo zjištěno, že disagregace a zkapalňování hovězího kolagenu začíná při teplotě 40 °C, zatímco u kuřecího kolagenu začíná až při 50 °C. Viskosimetrie dále potvrdila vyšší tepelnou stabilitu kolagenu z kuřecí kůže, jeho denaturační teplota byla 50 °C, což je rovněž o deset stupňů více než u hovězího kolagenu. Kuřecí kolagen obsahuje dvakrát vyšší množství lysinu, což poskytuje tepelnou stabilitu kolagenu. Na základě získaných výsledků lze říci, že vzhledem ke své vysoké tepelné stabilitě a vhodnému aminokyselinovému složení, kuřecí kůže může být použita jako alternativní zdroj kolagenu typu I s aplikacemi v potravinářském průmyslu a biomedicíně. Druhá část práce byla zaměřena na obohacení biomasy zelené mikrořasy C. sorokiniana selenomethioninem. Experimentální část byla provedena v Laboratoři biotechnologie řas na Univerzitě Huelva ve Španělsku. Cílem první části experimentů bylo studovat vliv selenu na životaschopnost řas, morfologii buněk a akumulaci SeMet v biomase mikrořasy kultivované v dávkových kulturách. Subletální koncentrace Se v živném médiu, 40 mgL-1 (212 M), snížila rychlost růstu o 25 % ve srovnání s kontrolní kulturou. Hodnota EC50 45 mgL-1 (238,2 M) byla stanovena pro selenan. Ultrastrukturální studie ukazovaly na strukturální změny chloroplastu (granulární stroma, redukce thylakoid). Elektroforéza proteinů z biomasy mikrořasy ukazuje, že Se ovlivňuje expresi genu enzymu Rubisco. C. sorokiniana byla schopna akumulovat až 140 mgkg-1 SeMet během 120 h kultivace. Další část experimentální práce byla zaměřena na obohacování biomasy mikrořasy C. sorokiniana selenomethioninem během kontinuální kultivace s použitím 2,2 L bioreaktoru v kultivačním médiu s přídavkem koncentrace selenu v rozmezí od 5 do 50 mgL-1. C. sorokiniana rostla stejně ve všech testovaných koncentracích selenu kromě koncentrace 50 mgL1, která byla již po krátké době kultivace letální. Během kontinuální kultivace se 40 mgL-1 selenu, bylo získáno maximálně 246 gL-1 selenomethioninu denně. Výsledky ukazují, že kultivace v dávkových kulturách a dlouhodobá kontinuální kultivace mikrořasy C. sorokiniana pro získaní biomasy obohacené SeMet je možná pečlivým výběrem podmínek kultivace a subletálních koncentrací selenu v živném médiu.
Proteome and Metabolome Changes in Selected Organisms under Stress
Halienová, Andrea ; Kráčmar, Stanislav (referee) ; Čertík, Milan (referee) ; Šucman, Emanuel (referee) ; Márová, Ivana (advisor)
Living conditions of every organism are influenced by various factors at this time. Some of them have positive effect on organism, some negative. Basic condition for surviving is the ability to resist and adapt to changing metabolic and living conditions. Every single stress effect can lead to changes in metabolism but organisms have ability to develope sufficient mechanisms for stress response. Some of them are similar for all living organisms (enzyme production, endogenous primary stress metabolites) some of them are specific for certain organism or stress type. Cell stress response can be observed on different levels (proteomic, genomic, metabolomic). In proper conditions it can be used indrustrially. In this work, influences of various stress factors were studied. These factors were applied on selected organisms – carotenogenic yeast and plant materials. Yeast stress response was induced by osmotic and oxidation stress factors. Changes on proteomic level and in production of selected secondary metabolites were observed. Proteome was analyzed by 1D and 2D electrophoresis with subsequent analysis of proteins by mass spectrometry. Yeast strain Rhodotorula glutinis CCY 20-2-26 showed the best adaptation to stress factors, which was moreover accompanied by overproduction of carotenoids. This finding can be premise for next industrial production of carotenoids. In plant samples predominantly enzymes and metabolites involved in antioxidant response were studied.
Study of Activity of Enzyma and Low Molecular Weight Antioxidant Systems
Macuchová, Simona ; Kráčmar, Stanislav (referee) ; Čertík, Milan (referee) ; Márová, Ivana (advisor)
Oxidative processes play important role in cell physiology and pathology as well. Balance of these processes is supplied by cooperating antioxidative systems; function of antioxidant defense systems depens on high levels of antioxidants in organism. Presented work is focused on developement and optimization of methods for analysis of important enzyme and non-enzyme antioxidants as well as total antioxidant capacity of selected types of biological material. Extractions and analyses of vitamin E, carotenoids, superoxide dismutase, catalase, peroxidase and lipoxygenase in barley and malt were optimized. RP-HPLC and HPLC/ESI-MS were used for analysis of vitamin E, phenolic and carotenoid content, spectrophotometry was used for enzymes activity analysis. A new methods for catalase and lipoxygenase activities were developed and compared with direct UV methods. Superoxide dismutase activity was determined by commercial diagnostic kit. A colorimetric method was used for peroxidase activity determination. Some kinetic parameters of enzymes were provided too. Optimized methods were used in the analyses of antioxidants in plant material - in barley and malt - in sets of samples of 6 varieties cultivated in four different locations for two years. Content of individual antioxidants differed depending on the variety, but usually were not found significant differences in the levels, depending on growing location. Perhaps climatic conditions have the greatest influence on levels of low molecular weight and enzymatic antioxidants at the specific location; oxidation processes are influenced both the quantity of moisture, both by sunlight, which induces oxidative processes in cultivated plants. The activity of antioxidants in barley caryopses is rapidly increasing during the malting process; an elevated temperature and moistness first induces activation the enzyme systems including antioxidant. In caryopsis is metabolic activity increased during which we can expect an increased production of radicals; for this purpose can antioxidant systems be activated that protect cells from damage by oxidative stress. In the second part of work optimized methods were applied in two clinical trials focused on study of the influence of exogenous antioxidants intake on metabolic and antioxidant status in human organism. In the first clinical study influence of food supplement containing polyunsaturated fatty acids and vitamin E on metabolism of hyperlipidaemics was evaluated. After 3-month supplemenation a lipid profile was improved and serum antioxidant levels increased. The second experiment was focused on enzyme and non-enzyme antioxidant levels in healthy subjects after temporarily intake of specific foods rich in antioxidants. After two-month intake plasma phenolic substances were slightly increased. Total antioxidant capacity and activities of enzyme antioxidants were not affected. Results of both clinical exeriments showed that supplying of antioxidants in natural form or in the form of food supplements does not markedly affect metabolism of healthy subjects, while in patients with chronic diseases antioxidant supplementation can positively influence metabolic status. Results of this work showed that optimized methods are suitable for analyses of antioxidant status parameters and also for monitoring of exogenous antioxidant intake.

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