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Monitoring of the influence of yeasts on the chemical and sensory qualities of manufactured wine
Petrášová, Ludmila ; Vítová, Eva (referee) ; Vránová, Dana (advisor)
The thesis deals with monitoring of the yeast's impact to the chemical and sensorial characteristics of produced wine. The aim of experimental part was obtaining of the aroma-active substances in the fermenting must and wine Hibernal and wine Pinot Blanc. SPME-GC-MS methods were used for identify wines and must aroma. The same autochthonous yeasts were used for wine production. This yeast was isolated from surface of grapes in our laboratory. It was found that both wines have a similar aromatic profile. The next aim was the monitoring of chemical parameters of samples and their changes. For this measurement were used spectrophotometric methods and HPLC methods. The last goal of the thesis was the isolation and identification of yeasts from wine Pinot Blanc by PCR-RFLP. These yeasts were then compared with yeasts isolated from Hibernal must. Identification of yeasts were done by amplification 5,8S-ITS DNA stretches using primers ITS1 and ITS4. Restriction endonuclease HaeIII, HinfI, HhaI and TaqI. were used for restriction analysis then.
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Aromatic substances of wine
Stávková, Markéta ; Vespalcová, Milena (referee) ; Ruibar, Jiří (advisor)
This bacherols thesis consists of two parts, of theoretical part and practical part. The theoretical part delimits wine-producing regions in Czech republic, explains growing of grapevine. The thesis is concerned with the soil classification, amount of mineral element and decribes the quality and aroma of a wine. It´s briefly concerned with bouquet of wine during wine production. Deals with chemical changes in must during fermentation using yeast. The practical part is concerned with soil analysis of vineyard Rajhradské Klášterní. The goal of this experimental part was to finding out amout of mineral elements in samples and their comparison between the four vineyard. Aromatics are analyzed by gas chromatography and sensory analysis.
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Verification of fermentative process of grape juice
Procházková, Lenka ; Nováková, Olga (referee) ; Vránová, Dana (advisor)
This thesis deals with identification of yeasts isolated during spontaneous fermentation of grape juice. For analysis the Pinot Noir grape variety grown in the integrated vineyard was chosen. In the theoretical part of this thesis basic information about yeasts are described. Genera of yeasts that occurs during fermentation process and methods based on PCR are also described. In this thesis PCR-RFLP method was used for identification of yeasts. The amplification of the 5,8S-ITS rDNA sequence was performed by the polymerase chain reaction with use of the primers ITS1 and ITS4. The restriction analysis was performed by applying five restriction endonucleases: HaeIII, HinfI, Taq?, AluI, MseI. The amplicons were split into fragments which length and number are typical for the particular species. These fragments were identified by agarose gel electrophoresis and electrophoreograms were evaluated by BioNumerics software. Dendrograms representing genetic similarity of isolated wine yeasts were created by using UPGMA cluster analysis.
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Testing of biological effect of glucans on cell lines in vitro
Šimková, Eva ; Holub, Jiří (referee) ; Němcová, Andrea (advisor)
The aim of this bachelor thesis is isolation and testing of -glucans from selected strains of yeast. In the theoretical part, characterisation of -glucans, microbial production of -glucans by yeast, determination of polysaccharides, exopolysaccharides and in vitro testing are described. Yeast have a cell wall made up of -glucans and -glucans are known for their healing properties. In the experimental part of this work deals with characterization of selected biomass yeasts in different forms and comparison of their effects and the amount of -glucans in each form. Stains of Metschnikowia pulcherrima, Cystofilobasidium infirmominiatum and Rhodotorula kratochvilovae have been selected for this thesis. Subsequently, the thesis deals with the isolation and testing of isolated -glucans from a selected lyophilised strain of yeast Rhodotorula kratochvilovae. The selected strain was isolated in 2 ways. The first method of isolation that was more friendly to conformation of -glucans due to the effect of ultrasonic homogenization of cells. The second method of isolation was less friendly to -glucans, using acid and base to homogenise them. Analyses of both extraction methods confirmed the presence of isolated -glucans, however it was found that the recovery of both methods was relatively low and requires further optimisation of the procedure. Overall, the better extraction procedure was the second method. A sample of this extract was further tested on the HaCaT cell line. The results of the pilot tests confirmed the cytotoxicity of the extract obtained by us.
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Production of carotenoids by red yeasts grown on some waste substrates
Kubáčková, Martina ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
Carotenoids belong to the most widespread and abundant classes of natural pigments with utilised in food industry, pharmacy and cosmetics. Presented work was realized as a comparative study of some substrates for cultivation of red yeast Rhodotorula glutinis, which produces carotenoid pigments. Yeasts were cultivated in different media with several waste substrates (for example potato fiber, apple waste, cereals, grains, etc.) as nutrition sources. To some substrates hydrolytic enzymes isolated from the fungi genus Fusarium were added. Majority of waste substrates were acceptable for cultivation. However, the best conditions for production of carotenoid enriched biomass (6,4 g/l of biomass enriched 3,2 mg /g of beta-carotene) exhibited media with hydrolytic fungal enzymes.
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Isolation and identification of yeasts from the vineyard to their possible utilisation in wine making
Fialová, Lenka ; Dudášová, Hana (referee) ; Vránová, Dana (advisor)
The aim of this work was to isolate the Saccharomyces cerevisiae yeast from the surface of wine grapes of the Malverina and Sauvignon varieties. Isolated yeasts were identified by the PCR-RFLP method. 5,8S ITS rDNA was amplified using PCR and restricition endonucleases HaeIII, HhaI, HinfI and TaqI were used for the restriction analysis which followed. The results were processed by UPGMA cluster analysis using the BioNumerics programme. The dominant genus on the surface of the Malverina variety grapes was Brettanomyces/Dekkera, while on the surface of the Sauvignon grapes we found mainly yeasts of the Pichia genus. The Saccharomyces cerevisiae species was not isolated from any of the two grape varieties.
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Selection of appropriate indigenous yeasts for wine production
Krátká, Veronika ; Babák, Libor (referee) ; Vránová, Dana (advisor)
The aim of this diploma thesis was the selection of appropriate indigenous yeasts for wine production. Tested yeasts were isolated from the grapes from the winery Maňák Žádovice. The yeasts isolated within theses in 2009 – 2012 have been also tested, and commercial wine yeast have been tested for comparison. In the theoretical part the focus is on the technology of wine, in particular fermentation. The work is also focused on yeasts metabolism and taxonomy. There was described the principle of PCR-RFLP, and methods used to characterize the properties of isolated yeasts. In the experimental part was made isolation of yeasts, theirs identification using PCR-RFLP and to select the most suitable yeast in wine making proces were performed physiological tests.
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Biological effects of complex extracts from yeast and algae biomass
Bočán, David ; Byrtusová, Dana (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis was focused on optimalization of extractions of active compounds from microalgae and carotenogenic yeasts. Other part of this work was focused on characterization of these extracts and their tests of cytotoxicity on human keratinocytes. In theoretical part a literary research which summarizes the basic properties and cultivation conditions of used microorganisms was conducted. Then there were listed an examples of antioxidant compounds found in these microorganisms as well as their properties. Finally the term cytotoxicity and methods of its measurement were clarified. The practical part of this thesis consists of series of extractions from mentioned microorganisms. These extracts were characterized by the content determination of phenolic and flavonoid compounds and also chlorophyll and carotenoid compounds. Determination of antioxidant capacity and SPF were done too. Lastly the cytotoxicity of chosen extracts was measured using the MTT test.
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Monitoring of wine yeasts population during fermentation of wine cider
Krätschmerová, Kateřina ; Vojtíšková, Marie (referee) ; Vránová, Dana (advisor)
This thesis deals with identification of wine yeasts isolated during fermentation process of wine cider and grapes of Sauvignon grape variety, grown in the integrated vineyard. The identification and taxonomic classification is faster and easier due to the progress of molecular methods. In this thesis PCR-RFLP method was used for identification of yeasts. Sequences of DNA specific for each species were analysed. These sequences were amplified by means of PCR method and by using ITS1 and ITS4 primers. In following step, they were put through the restrictiction analysis with five restriction endonucleases. Fragments of DNA were separated by horizontal electrophoresis. The electrophoreograms were evaluated by BioNumerics software and final dendrogram representing genetics similarity of isolated yeasts was created by using UPGMA claster analysis. The basic information about yeasts and their identification by molecular methods are described in the theoretical part of this thesis.
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Identification of wine yeasts by PCR-RFLP method
Šuranská, Hana ; Vojtíšková, Marie (referee) ; Vránová, Dana (advisor)
This thesis deals with identification of the wine yeasts by applying the PCR-RFLP method. The identification and characteristic of the yeasts has gone through substantial changes in recent years. There have been introduced new methods of taxonomic classifying based on the molecular methods, which are oriented to easy and fast identification. One of these methods is the PCR-RFLP method. The amplification of the 5•8S-ITS rDNA sequence by the polymerase chain reaction with use of the primers ITS1 and ITS4 leads to the amplification of the specific sequence of DNA. Such multiplied DNA is after repurifying by the ethanol and drying submitted to the restriction analysis. With use of the restriction endonuklases DNA is chopped into the specific segments typical for the particular genus. The chopped fragments can be separated in the electric field in the agarose gel and subsequently evaluated. In this thesis together 63 type yeasts were used. These yeasts were analysed by applying of the seven restriction endonuklases – HaeIII, HhaI, HinfI, HpaII, TaqI, AluI a MseI. The final image of type yeasts splitting was compared to the results of splitting of already identified wine yeasts and these yeasts were subsequently taxonomically classified. Evaluation of genetic similarity was conducted by program BioNumerics and as the results the dendrograms that were created with use of Jaccard‘s coefficients are obtained.
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