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Potential use of waste lipid substrates and glycerol to production of carotenoids by yeasts
Kostovová, Iveta ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
The aim of this study was use of lipid waste substrates and waste glycerol as carbon sources for red yeasts. Six yeast strains, namely Rhodotorula glutinis, Rhodotorula rubra, Rhodotorula aurantiaca, Cystofilobasidium capitatum, Sporobolomyces roseus and Sporobolomyces shibatanus were used for cultivation. All studied yeast strains were able to utilize glycerol and rapeseed oil as a carbon source. Cultivation in oil medium was in most of strains accompanied by decreased production of carotenoids. Increased production of ergosterol, lycopene and biomass was observed in some strains only. Most of yeast strains cultivated in glycerol medium produced increased amount of biomass as well as carotenoids. The best producer of bi-omass and pigments was yeast strain Sporobolomyces roseus CCY 19-6-4 grown in medium containing glucose and glycerol in a 1:1 ratio.
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Production of proteolytic enzymes by selected microorganisms
Pala, Martin ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
Presented work was focused on study of microbial production of proteolytic enzymes used in many industrial applications. Bacterium Bacillus subtilis was used for laboratory production of microbial proteolytic enzymes. During cultivation production of biomass and proteolytic enzymes were studied influence of substrate type and stress factor application (osmotic shock, hydrogen peroxide and ethanol) was tested too. The highest concentration of biomass was measured in concentrated BM medium after 32 hours of cultivation. Biomass yield was 1.11 g/l. The highest protease activity (88.28 U/ml) was obtained in the same cultivation medium and time of cultivation. According to results of stress experiments it can be concluded that most of used stress factors exhibited a toxic effects to bacterial culture even at low concentrations.
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Controlled production of polyhydroxyalcanoates by bacterial strain Ralstonia eutropha using different substrates
Šnajdar, Ondřej ; Duroňová, Kateřina (referee) ; Márová, Ivana (advisor)
This bachelor’s thesis deals with production of polyhydroxyalkanoates (PHA) by bacterial strain Ralstonia eutropha. Production of PHA on different substrates has been studied to lower the costs of feedstock. In theoretical part the review has been done about the most important types of PHA, production strains and possibilities of cultivation of Ralstonia eutropha using different substrates. In practical part there has been studied production of PHA on different vegetable oils, including waste oils from different sources (restaurants, homes, food companies). Incorporation of different precursors for copolymer production control was studied too. The highest yields of poly-3-hydroxybutyrate (P3HB) have been achieved using waste oils. For economical and ecological reasons these oils are very suitable substrates. Using concentration 20 g/l of waste rapeseed oil from university canteen there has been produced 13,32 g/l of biomass containing 58,63% of P3HB in 84th hour of cultivation. The highest yield of PHA in precursors study has been achieved applying 1% propanol in 24th hour of cultivation. The PHA increase has been 97%. This PHA was composed from 91% of 3HB and 9% of 3-hydroxyvalerate.
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Use of diffrent nutrition source by selected carotenogenic yeasts
Čačková, Katarína ; Starečková, Terezie (referee) ; Márová, Ivana (advisor)
Carotenoids are the most common naturally occurring terpenoid pigments. Because of their positive biological functions, carotenoids represent a group of important molecules for the pharmaceutical, chemical, food and feed industries. This work was realized as a comparative study focused on use of some waste substrates as nutritional sources for production of carotenoid pigments by red yeast Rhodotorula aurantiaca. Yeast were cultivated in different media with selected waste substrates – apple fiber, whey, wheat etc. To some media hydrolytic enzymes prepared from some fungal strains were added. Most of waste substrates seems to be useful for R. aurantiaca cultivation. As the best nutritional sources for enriched biomass and carotenoid production apple fiber or wheat processed by mixed preparative of extracellular hydrolases from Fusarium solani were found.
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Changes of antioxidants in selected fruits during long-term freezing
Štindlová, Jitka ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
In this bachelor thesis some low molecular weight antioxidants contained in strawberries, raspberries, blueberries and cranberries are described. In the theoretical part also general characteristics of these fruits are introduced. Experimental part was focused on analysis of the changes of selected antioxidant content in the fruits. These changes were monitored during storage in two different conditions – in refrigerator and in freezer. In refrigerator whole fruits were stored for 8 days. The experiment in the freezer was performed for 2 months and the fruits were stored in four different processed forms – as a whole fruit, whole fruit impregnated by sucrose solution, as a pulp and pulp mixed with sucrose. Antioxidant content in fruits was analyzed by HPLC and spectrophotometry. The highest total content of antioxidants was found in strawberries, while the lowest values were found in raspberries. During storage some part of original antioxidant content stayed conserved, the highest content was preserved in blueberries processed as a whole fruits and impregnated whole fruits.
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Characterization of active substances in several kinds of beer
Benešová, Pavla ; Obruča, Stanislav (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis is to analyse biologically active compounds, especially of phenolic character, in 10 kinds of alcohol-free beer in comparison with alcoholic beer. In theoretical part basic steps of brewery technology are described including alcohol-free beer production. Characteristic compounds occurring especially in Czech beer e.g. proteins, phenolics, bitter substances and also methods for their analysis are discussed as well. Microfluidic electrophoresis (Experion, BioRad) was used to beer protein analysis. Phenolic compounds, flavonoids, technological characteristics and antioxidative activity were measured by spectophotometry. Individual phenolics of selected beers were identified and quantified by LC/ESI-MS analysis too. In alcohol-free beers similar concentrations of biologically active compounds were found in comparison with alcoholic beers, especially in the case of beer phenolics.
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Active substances in cereal products for baby food
Hurtová, Jana ; Pařilová, Kateřina (referee) ; Márová, Ivana (advisor)
Present bachelor thesis is focused on the study of antioxidant substances in cereal products for baby food. The theoretical part is aimed at describing the anatomical structure and chemical composition of cereal grain, characterization of antioxidants with the focus on natural antioxidants, the technology and nutritional parameters of cereal products. The experimental part deals with the content of phenolic compounds, flavonoids, and the total and reducing sugars in the total of 12 kinds of cereal products with different flavour – 5 types of oak pap, 3 types of fiber pap and 4 corn paps. The work includes the analysis of ascorbic acid by titration method and the analysis of tocopherol, carotenoids and catechins by high performance liquid chromatography as well. The highest content of total phenolics and flavonoids was found in corn pap with raspberries and also in cereal pap with chocolate. High levels of vitamins E and C were found predominantly in flavoured fiber pap.
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Study of biocompatible polymers degradation
Oborná, Jana ; Márová, Ivana (referee) ; Vávrová, Milada (advisor)
This bachelor thesis is focused on biocompatible polymers degradation study. Both poly(D,L-lactic-co-glycolic acid)-g-polyethyleneglycol-g-poly(D,L-lactic-co-glycolic acid) copolymers and their forms modified with itaconic acid were monitored. This work verified the optimal analytical procedure for monitoring the degradation of investigated copolymers. Bio-degradation of polymers occured at 37 °C in phosphate buffer with pH=7.4. High performance liquid chromatography with UV-VIS detection of diode-array type was used for determation of the degradation products. Gel permeation chromatography with refractive index detector was used for the assesment of the change of molecular weight polymer chain after the degradation.
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Regulation of polyhydroxybutyrate production in Wautersia eutropha
Grossová, Marie ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
The aim of this work is study of microbial production of biodegradable polymers (polyhydroxyalkanoates; polyhydroxybutyrate PHB). Bacterium Wautersia eutropha was used for laboratory production of PHB. In this bacterium application of exogenous stress factors (osmotic shock, hydrogen peroxide and ethanol) was tested to enhance PHB production. Influence of exogenous stress on bacterial culture depended on stress factor concentration and time of stress application. Substantial influence on PHB yield exhibited changes of biomass production during stress experiments. The main part of this work is focused on study of PHB production in microbial cells exposed to stress in different growth phases. Application of strong stress in early phases of growth led to PHB and biomass decrease. The most suitable seems to be application of stress at the beginning of stationary phase accompanied by increase of PHB formation. Concentration of stress factor could be optimized too. The highest yields were obtained after addition of 0.5 % ethanol into production medium at 60th hour (PHB increase 21 %). These results can form a basis for new fermentation strategy which leads to enhanced effectiveness of PHB production.
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Analysis of phenolics in different kinds of coffee
Jašková, Martina ; Halienová, Andrea (referee) ; Márová, Ivana (advisor)
The aim of this bachelor thesis was examining the quantity of biologically significant substances in selected types of roasted ground coffee, instant coffee and coffee extract. The particular kinds of coffee differed in technological processing, degree of roasting and composition. In the practical part total phenolics and flavonoids by using spectrophotometry methods. The total antioxidant activity in the individual coffee extracts was determined by ABTS method. Qualitative and quantitative analysis of some individual antioxidants and caffeine was performed using RP-HLPC with spectrophotometric detection. As a part of the work sensory analysis of all coffee samples was realized and consumer questionnaires were completed.
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