|
|
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.
|
|
|
PRODUCTION OF BETA-GLUCANS AND OTHER POLYSACCHARIDES BY YEAST AND MICROALGAE
Byrtusová, Dana ; Kráčmar, Stanislav (referee) ; Kovalčík, Adriána (referee) ; Márová, Ivana (advisor)
Beta-glukany jsou polysacharidy složeny z monomerů D-glukózy. V dnešní době se -glukany těší zvýšené pozornosti zejména kvůli imunomodulační aktivitě a využitelnosti ve farmaceutickém a potravinařském průmyslu. Saccharomyces cerevisiae je dodnes jediným kvasinkovým zdrojem požívaným v biotechnologické produkci. Avšak některé kvasinky z oddělení Basidiomycetes, které jsou schopny produkce lipidů a karotenoidů, mohou být využity rovněž jako alternativní zdroj -glukanů. Dizertační práce se zabývá možností a optimalizací produkce -glukanů a dalších mikrobiálních sacharidů u karotenogenních kvasinek a mikrořas. Testovány byli zástupci rodů Rhodotorula, Sporobolomyces, Cystofilobasidium a Dioshegia. Z nekarotenogenních kvasinek byly do screeningu zařazeny kvasinky rodu Metschnikowia, askomycetní kvasinky a z mikrořas zástupci zelených a červených řas. Experimentální část cílí rovněž na možnosti koprodukce dalších metabolitů, jako jsou lipidy, pigmenty a extracelulární polymery. První část experimentu se zabývá vlivem čtyř C/N poměrů (10:1, 40:1, 70:1 a 100:1) na produkci biomasy, -glukanů, karotenoidů a lipidů. Ze všech testovaných kmenů, S. cerevisiae CCY 21-4-102, C. infirmominiatum CCY 17-18-4, P. rhodozyma CCY 77-1-1 a R. kratochvilovae CCY 20-2-26 vykazovaly nejvyšší produkci -glukanů a byly proto vybrány k podrobnější optimalizaci, zejména osmotického stresu, teploty a zdroje dusíku v kultivačním médiu. Dodatečně, kmen R. kratochvilovae CCY 20-2-26 je schopný produkce extracelulárních glykolipidů a S. pararoseus CCY 19-9-6 extracelulárních polysacharidů. Následně bylo stanoveno množství -glukanů u dalších dvanácti kmenů S. cerevisiae a rovněž možnost produkce polysacharidů u mikrořas.
|
|
|
Biotechnological production of selected metabolites on whey substrate
Gadová, Martina ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
The submitted master thesis deals with assessment of the possibility of using of cheese whey for biotechnological production. Study content composition of lyophilized whey, optimization of acid hydrolysis and preparation of cultivating mediums with different content and treatment of cheese whey. Between the aims of this thesis belong also screening of microbial producers, interesting for biotechnology and looks at their growth and production of selected metabolites of cultivation mediums containing cheese whey. All substrates and produced metabolites where examined with UHPLC-PDA-RI and GC-FID: Amount of produced microbial lipids was determined by gravimetric analysis. Examined microorganisms belonged to yeast genus Saccharomyces, Metschnikowia and bacterial genus Lactobacillus and its focused on production of ethanol, microbial lipids and lactic acid. The highest yields with using yeasts were obtained using production medium containing hydrolysed lactose in cheese whey. The highest production, in case of bacteria, was obtained using non-hydrolysed, untreated cheese whey production medium.
|
|
|
Speciation analysis of selenium in selenized yeast
Motlová, Tereza ; Vitoulová, Eva (referee) ; Diviš, Pavel (advisor)
The aim of the theses was determination of selenium species in yeast Saccharomyces cerevisiae cultivated in medium with added inorganic form of selenium (Sodium Selenite). Concentrations of Sodium Selenite in cultivation medium were 0,1; 1; 10 and 100 mg.l-1. Cultivation was undertaken in fermenting tub for period of 72 hours. Cultivated yeasts were extracted by use of enzymes and subsequently the species of selenium in particular parts of yeasts were determined. In order to determine selenium species, the method of high-performance liquid chromatography in combination with atomic fluorescent spectrometer and technique of hydride generation was used. Having analysed different fractions of the yeasts Saccharomyces cerevisiae it was ascertained that during cultivation the sorption of selenium occurred in form of Se4+ in cell membranes while in cytoplasm no inorganic forms of selenium were found. Furthermore, it was stated that yeasts Saccharomyces cerevisiae are able to metabolically change inorganic forms of selenium to organic forms (selenomethionine), while these forms are present in cytoplasm and they are likely to be bound to proteinic structures of cell membranes. An increase of concentration of Se4+ in cell membranes could be observed as a result of increasing concentration of Sodium Selenite in cultivation medium. In proteinic structures the concentration of organic selenium forms increased only to concentration 10 mg.l-1 of Sodium Selenite in cultivation medium.
|
|
|
Study of yeasts transglycosylases
Čurillová, Natália ; Ing.Hana Schusterová, Ph.D. (referee) ; Stratilová, Eva (advisor)
This study is interested in properties of fungal transglycosylases, specifically Phr1, Phr2 and Crh2. These enzymes are involved in the remodelling of yeast cell walls due to their cleavage of structural donor polysaccharides and transfer of their fragments to the other acceptor (poly)saccharide molecules. The mammalian cells do not contain cell walls, nor cell wall transglycosylases, that´s why these enzymes are possible targets for antifungal agents. In this diploma thesis the effect of 67 commercially available inhibitors on Phr1 and Phr2 enzymes was studied by rapid screening. In the case of the Phr1 enzyme, two inhibitors showed a potential effect which was subsequently tested by size exclusion chromatography column incorporated into HPLC device. None of the inhibitors were found to have an inhibitory effect on Phr1 or Phr2 enzymes in contrast to DMSO in which all inhibitors were dissolved. The mode of action of Phr enzymes was also studied by thin layer chromatography and high performance liquid chromatography. The first method allowed to monitor the formation of products only in the later stages of the reaction, but more sensitive size exclusion chromatography showed the product formation at the beginning of the reaction. Phr1 cleaved the donor substrate near the non-reducing end and forms small fragments that are transfered to labeled acceptors during the whole reaction. Phr2 utilized random action pattern, thus creating products with higher molecular weight from the beginning of reaction. The effect of the polymerization degree of acceptor on it´s affinity with the Crh2 was also studied. The Michaelis-Menten constants showed no effect of acceptor lenght on the affinity between enzyme and substrate.
|
|
|
Monitoring of the influence of indigenous culture of yeasts on the fermentation process of making wine
Michálek, Petr ; Molnárová,, Jana (referee) ; Vránová, Dana (advisor)
This thesis deals with the identification of wine yeasts isolated from the grape must using PCR-RFLP method. The yeasts were isolated from Pinot Noir grape variety must. Grapes were grown and produced in accordance with the requirements placed on organic and integrated farming. Samples were processed in the laboratory, where pure cultures of individual yeast were obtained. A commercial kit was used for yeast DNA isolation. Obtained DNA was used for further analysis. Using the polymerase chain reaction and the primers ITS1 and ITS4 a specific segment of 5.8S rDNA-ITS region was amplified. The PCR products were then detected by electrophoresis in an agarose gel, and after a subsequent purification, three restriction enzymes: HaeIII, HinfI and HhaI were subjected to restriction analysis. The DNA was digested to fragments specific for yeast species and they were detected by agarose electrophoresis. Similarity of these isolates was compared using BioNumerics program and the result is dendrogram of genetic similarity of isolated yeast. The basic chemical analysis of samples must was also performed.
|
|
|
Monitoring of the influence of commercial culture of yeasts on fermentation wine making process
Šerý, Filip ; Vojtíšková, Marie (referee) ; Vránová, Dana (advisor)
This diploma thesis focuses on isolation and taxonomic classification of yeast species isolated during the red wine (Pinot noir) fermentation. Grapes were grown under organic and integrated farming in South Moravia wine region, Czech Republic. Processing was controlled – for inoculation was used strain Saccharomyces cerevisiae BS6. Polymerase chain reaction followed by restriction fragment lenght polymorphism of PCR-amplified fragments (PCR-RFLP) was used for yeast species identification. For DNA analysis we used coding region of 5.8S ITS rDNA which was amplified using ITS1-ITS4 primers. Amplicon was digested by three restriction endonucleases - HaeIII, HinfI and HhaI. Isolates were divided into eleven groups using UPGMA cluster analysis (software BioNumerics). We identified following yeast species: Candida valida, Candida vini, Issatchenkia occidentalis, Pichia fermentans, Saccharomyces cerevisiae and Zygosaccharomyces bailii. We were not able to identify some yeast species. Differences between organic and integrated farming were demonstrated with varying composition of yeast species.
|
|
|
Raw materials and microorganisms to distilled beverage production
Jechová, Iva ; Vitoulová, Eva (referee) ; Babák, Libor (advisor)
The production of distilled ranks among established fermentative production. Than the first – quality spirits is became from raw material, it is obliged to change ranks processes. The important from the processes are alcoholic fermentation, which proceeds owing to mikrobiological cultures, distillation and subsequent rectification and at not least ranks aging distilled, for which is necessary selected appropriate container. For all processes the granted conditions are appointed, under which the processes would ocur, so resulting distilled achieved the first – quality and the best sensory character. Therefore this work does one’s best map these single processes and it is largely intent on fermentative processes.
|
|
|
Kvasinky jako součást mikrobioty osidlující potravinové suroviny a potraviny
Ferbyová, Kateřina
In the literary research this thesis summarizes general information about the yeast genera, including cytology, morphology, and physiology of the cell. Yeasts are being classified within taxonomy. Some of the most important genera found and used in the food industry are characterized. Theses then describes both the cultural and contaminating microbiota of main food groups. Lastly, the paper describes some commercially used preservation techniques. The experimental part of this thesis is focused on assessing total microbial count (TMC) and yeast and mold count in two samples of spontaneously fermented beer as well as two samples of wine with different treatment. This is to capture the natural microbiota of these alcoholic beverages. In the case of yeast and mold count, samples were inoculated in chloramphenicol yeast glucose agar, in the case of TMC the plate count agar (PCA) was used. Found yeast was reinoculated in order to obtain a pure culture strain. Yeasts were identified using a CANDIDA-screen set (Erba-Lachema). C. glabrata, C. krusei, C. lipolytica and S. cerevisiae were found. Molds have been found on PCA. They were isolated and identified under microscope based on their morphological features. 3 Penicillium molds and 1 Aspergillus mold were identified.
|
|
|
Diversity, ecology, and biotechnological potential of yeasts associated with bark beetles
Havlíček, Václav ; Kolařík, Miroslav (advisor) ; Novotný, David (referee)
Bark beetles (Coleoptera; Scolytinae) attack woody plants, which is why they are considered pests from a human perspective. They owe their evolutionary success, among other factors, to numerous symbioses with microorganisms, with fungi playing a significant role. The mycobiome of bark beetles is dominated by yeasts, which, nevertheless, are widely overlooked. Intestinal yeasts not only from Ips typographus but also from other species of bark beetles have potential for future biotechnological applications. The aim of this study was to examine their diversity and physiological activities, which will help clarify their ecological role and biotechnological potential. Collections were conducted in the Czech Republic from larvae of the spruce bark beetle Ips typographus and from various species of subcortical insects in Kenya. Yeasts were identified and taxonomically classified based on rDNA sequencing. A total of 133 yeast strains belonging to 37 species were identified, including 9 species that could not be identified and belong to previously undescribed species and in two cases also genera. A total of 133 yeast strains belonging to 37 species were identified, including 9 species that could not be identified and belong to previously undescribed species and in two cases also genera. The most frequently...
|
guest ::
