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Microbial production of carotenoid pigments using waste substrates
Němcová, Andrea ; Ing.Martina Čarnecká, Ph.D. (referee) ; Márová, Ivana (advisor)
Carotenoids are naturally occurring pigments produced by bacteria, yeasts, filamentous fungi and plants. They exhibit significant biological effects and are widely used in the food industry, pharmacy and cosmetics. The aim of this diploma thesis proposed as a comparative study was regulation of carotenoid and ergosterol production in red yeasts using several waste substrates as whey, corn germs, wheat, apple fiber and pasta. To selected production media extracellular hydrolytic enzymes degrading polysaccharide were added. These enzymes were obtained from the cultivation media of four fungal strains. In this study three carotenogenic yeast strains were used: Rhodotorula glutinis, Sporobolomyces roseus and Cystofilobasidium capitatum. All strains were cultivated simultaneously and changes in biomass and carotenoid production in different production media were monitored and compared. As the best waste substrate apple fiber was utilized, particularly in Rhodotorula glutinis, which exhibited mainly biomass production increase. In Sporobolomyces roseus increased production of biomass and carotenoids have been reported in media with hydrolyzed fiber and pasta as well. Beta-carotene production in this strain reached 4776,38 mg/g of dry weight. The strain Cystofilobasidium capitatum exhibited in waste media a decerase of biomass production accompanied with increased production of carotenoids, especially in wheat mush and pasta medium hydrolyzed by enzyme preparative from Aureobasidium pullulan. It can be concluded that hydrolyzed waste substrates are very hopeful as cheap nutrient sources for yeast strains producing carotenoids and ergosterol. Nevertheless, further study of substrate processing for individual strains is needed.
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Preparation of some application formula of antimicrobial substances
Krempaský, Kamil ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The main aim of this study is to determine antimicrobial activity of herbal extracts and also encapsulate these extracts and lysozyme to liposomes. The extracts were prepared from above ground part of wormwood (Artemisia absinthium), aerial part of breckland thyme (Thymus serpyllum), the root of purple coneflower (Echinacea purpurea), liquorice (Glycyrrhiza glabra), corolla of pot marigold (Calendula officinalis) and berries of sea buckthorn (Hippophae rhamnoides). In all extracts antioxidant activity and the amount of total polyphenols and flavonoids was determined. All of these extracts and also lysozyme were used for encapsulation to liposomes. Prepared liposomes were then tested for their stability. Further, encapsulated as well as free extracts were tested for their antimicrobial activity on Escherichia coli, Serratia marcescens, Micrococcus luteus and Bacillus subtilis. Extract from Echinacea purpurea showed the highest antimicrobial activity.
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Characterization of organic nanoparticles with encapsulated antimicrobial peptides
Vejrostová, Petra ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
This bachelor thesis is focused on characterization of particles containing encapsulated antimicrobial enzyme lysozyme. The theoretical part deals with characterization of antimicrobial peptides and their description. Further part of review was focused on lysozyme, the selected representative used in this thesis, its structure, mechanism of action and possible usage. In the experimental part the Hartree-Lowry method was used for lysozyme detection, determination of encapsulation efficiency and for detecting the amount of lysozyme released after incubation in model physiological environment and in model foods. In process of encapsulation the highest amount of lysozyme was packed into 1% chitosan particles, manually prepared alginate particles and into liposomes. During study of stability of particles in model foods as the least stable manually prepared chitosan particles were found. The released lysozyme exhibited changes probably caused by its degradation. The highest influence on particles proved 3% acetic acid. During studying the stability of the particles in artificial digestive fluids as the most unstable manually prepared chitosan particles were found, while alginate particles were the most stable. The thesis also deals with changes in antimicrobial activity of encapsulated lysozyme in prepared particles and after its application into the model environments. A gram-positive bacteria Bacillus subtilis was used in order to test the antimicrobial activity. Antimicrobial tests showed that after encapsulation antimicrobial activity of lysozyme was substantially decreased in most samples. Size and stability of prepared particles was tested using dynamic light scattering.
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Use of wastes from winemaking in food and cosmetics applications
Výmolová, Markéta ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The presented thesis deals with the various types of hydrolysis of waste from the production of wine, parings and bunch-stems for subsequent biotechnological use as enrichment of feeding mixtures and the production of bio-ethanol. A composite analysis was done at the start of the measurements for the determination of dry matter, extraction of oil from the parings and assessment of cellulose in the bunch-stems. As a part of this thesis a chemical and enzyme hydrolysis of waste materials have been performed. In hydrolysates the contents of reducing carbohydrates and antioxidants, polyphenols and flavonoids were analysed. The results showed that the samples with a concentration of 50 g/l of material hydrolysed in a water bath for 60 minutes were the best conditions for cultivating yeasts. Hydrolysed parings and bunch-stems were used as the production medium for the production of ethanol in Saccharomyces cerevisiae. A change of the concentration of carbohydrates and ethanol in the samples has been measured by HPLC. The sample hydrolysed enzymatically using cellulase exhibited the highest concentration of biomass (c = 2,140 g/l), the sample hydrolysed chemically in the water bath formed the highest content of ethanol (c = 9,880 g/l).
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Preparation and use of selected nanoparticles in cosmetics
Hoová, Julie ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The Bachelor thesis is focused on preparation and use of selected nanoparticles in cosmetics. The theoretical part deals with general characterization and use of caffeine, phenolics and vitamin C in cosmetics. Further, characterization of liposomes and possibilities of encapsulation of active substances gained from natural sources were introduced. In experimental part liposomes with encapsulated active substances were prepared by three different techniques. Encapsulation efficiency was determined by HPLC/PDA, phenolics spectrophotometrically and vitamin C by titration. Prepared particles were monitored for size and stability by dynamic light scattering. Furthermore, long-term stability of liposomes in model conditions was evaluated as the amount of the active substances released during incubation. In this work was found out that from all tested samples co-encapsulated liposomes are probably the best application form which can be used in face lotion or gel. Co-encapsulated liposomes exhibited relatively high encapsulation efficiency, good stability and thanks to quality of active substances they meet customer’s requirements of cosmetic industry.
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Characterization and stabilization of pancreatin
Wurstová, Agáta ; Němcová, Andrea (referee) ; Obruča, Stanislav (advisor)
This work focuses on a study of enzyme mixture pancreatin, its characterization and subsequent encapsulation into liposomes. As a reference proteins bovine serum albumin and trypsin were used. Characterization of pancreatin consisted of two parts. The first part focuses on optimization of methods for the concentration determination by absorption spectrophotometry using basic methods for identifying proteins (Biuret method, Hartree-Lowry method and Bradford method). Moreover, UV spectrums of the protein were measured. As a method for identification of protein´s molecular weight, SDS-PAGE was used. To identify components of pancreatin, LPLC was employed in two modifications, ion-exchange chromatography and size exclusion chromatography. The second part is dedicated to the characterization of pancreatin as enzyme in terms of pH and temperature optimum for the enzyme activities of protease (pH 9, 8 and 50 °C), amylase (pH 7 and 40 °C) and lipase (pH 7 and 50 °C). The last part of this work aimed at an encapsulation of pancreatin into liposomes and DLS analysis of distribution of particles and their zeta potential. Liposomes did not spontaneously release encapsulated enzyme. To confirm that proteins were successfully entrapped into liposomes, their structure was disrupted by application of phospholipase D. In conclusion, liposomes can be utilized as delivery systems for native enzymes.
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Production of mcl-PHA by selected bacteria
Eremka, Libor ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
The aim of this work is to study the possibility of microbial production of polyhydroxyalkanoates with medium chain length (mcl-PHA). For production two bacterial strains were used: Pseudomonas putida and Pseudomonas aeruginosa. Theoretical part of bachelor thesis deals with the biosynthesis of polyhydroxyalkanoates, their material properties and microbial producers. In experimental part selected bacteria were cultivated on different substrates to evaluate their ability to utilize various carbon sources and accumulate mcl-PHA. Content and composition of mcl-PHA accumulated in biomass were analyzed by gas chromatography with FID. Pseudomonas putida produced more mcl-PHA in medium containing canola oil as sole carbon source when compared with Pseudomonas aeruginosa. P. putida produced 2,11% mcl-PHA in medium containing glycerol as carbon source.
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Regulation of production of enriched biomass and lipidic substances in carotenogenic yeasts.
Němcová, Andrea ; Ondruška, Vladimír (referee) ; Márová, Ivana (advisor)
Carotenoids belong to the most abundant classes of natural pigments with important biological functions. In last years intensive studies focused on biotechnological production of carotenoids by suitable microorganisms were done. Presented work was realized as a comparative study of three yeast strains: Rhodotorula glutinis, Rhodotorula rubra a Sporobolomyces roseus. These strains were cultivated in different media with several waste substrates (potato extract, whey) as nutrition sources. Additionally, strains were exposed to some types of exogenous stress. All strains were able to use tested waste substrates as nutrition sources. Most of strains exhibited increased carotenoid production, in several conditions accompanied by high biomass formation. As the best producer of enriched biomass yeast strain Rhodotorula glutinis CCY 20-2-26 cultivated on medium with addition of lyophilized whey (9 g/l of biomass enriched by 2 mg/g of beta-carotene) and/or under mild salt stress.
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Communication strategy
Němcová, Andrea ; Zeman, Jiří (advisor) ; Filipová, Alena (referee)
The aim of this master thesis is to suggest possible improvements for the current communication strategy of Czech Centre Munich -- one of the offshore branches of the government agency Czech Centres. This thesis is divided into two parts -- theoretical and practical. Important terms (such as marketing and communication) are explained in the theoretical part with a focus on their modifications in the sector of services and cultural sphere. The practical part presents the structure of Czech Centres, their field of activities and their communication structure. This part also introduces Czech Centre Munich with its activities, partners and communication instruments. The communication strategy is analysed through a direct observation and a quantitative questionnaire. The final part of this thesis evaluates and states recommendations for the communication strategy.
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Marketing strategy analysis of E.ON corporation
Němcová, Andrea ; Zeman, Jiří (advisor) ; Filipová, Alena (referee)
The aim of this bachelor thesis is to analyse the current marketing strategy of E.ON corporation and on the basis of the data I have gathered I suggest possible improvements. This thesis is divided into two parts -- theoretical and practical. Important terms (such as marketing, marketing surroundings and marketing strategy) are explained in the theoretical part. The practical part focuses on introduction of E.ON Energie, a.s., description of the electricity market and characterization of customers of E.ON Energie, a.s. and its competitors. In this part marketing mix instruments are also examined and the SWOT analysis is set out. The end of this thesis deals with evaluation of and recommendations for improvements of the current marketing strategy.
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