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Authenticity of natural plant component in cosmetics products
Kubalová, Michaela ; Fialová, Lenka (referee) ; Němcová, Andrea (advisor)
The purpose of this thesis was to study the authenticity of selected natural ingredients in cosmetic products. These were specifically cosmetic products that contained citruses, mint or lavender. Commercially available isolation kits were used for DNA isolation. The presence of plant origin DNA was verified by PCR method using primers specific for the ITS2 region of plants. The presence of limonene, a significant allergen contained in said plants, was determined in the samples by PCR method using primers for limonene synthase. At the same time, its presence was verified by HPLC method. In addition, two primers were tested for lavender and monitored for their efficacy, with no significant difference in the usage.
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Control of metabolism of carotenogenic yeasts on molecular level
Pokrývková, Zuzana ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
This diploma thesis deals with the molecular characterization of carotenogenic yeasts. The techniques used for the analysis of the conserved regions of the D1/D2 rDNA region of the 26S ribosomal large subunit region and the ITS1 and 5,8-ITS2 regions were nested PCR and DGGE. The results of DGGE show that all analyzed yeast strains have very similar sequences of these regions The yeast Rhodotorula mucilaginosa with the collection number CCY 20-7-28 showed differences from the other carotenogenic yeast strains. As a part of melucular characterisation using ribosomal gene sequences, eight yeast strains were examinated for substrate utilisation tests using different substrates. Characterisation of growth and metabolite production was tested in each strain too. The next aim of this thesis was to prepare a carotenoid yeast strain characterized by overproduction of metabolites, in particular carotenoids and lipids,. Yeasts were subjected to a random mutation caused by UV irradiation and the influence of this mutantagen onthe production of metabolites was evaluated. As a candidate yeast strain C. capitatum CCY 10-1-2 was selected. This selection was based on previous studies due to its good production of lipids using waste glycerol as asubstrate. This strain was subsequently adapted to waste whey, glycerol, and a glucose as a basic carbon source.
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Detection of probiotic bacteria in diary food products using PCR technique
Klaška, Dominik ; Brázda, Václav (referee) ; Smetana, Jan (advisor)
In the bachelor thesis, DNA was isolated from commercially available white yogurt. The isolated DNA, which was gained by two different methods, was performer analyse by a spectrophotometer. Both methods provided sufficiently concentrated and high-quality DNA for further analysis by PCR. Precisely defined sections of isolated DNA were amplified using specific primers. The presence of the bacterium domain was detected, and in the case of genus specific amplification, the presence of bacteria of the genus Lactobacillus was detected too, by gel electrophoresis.
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Determination of Staphylococcus aureus and Bacillus cereus in confectionery products
Vdolečková, Monika ; Necidová,, Lenka (referee) ; Šárka,, Bursová (advisor)
This bachelor thesis focuses in the theoretical part on the description of bacteria Bacillus cereus and Staphylococcus aureus, as bacteria that can contaminate raw materials of either plant or animal origin. Both of these bacteria can be found in soil, water, but we can also encounter them on our skin. This fact can aid contamination in the manufacture of confectionery products. In the experimental part, samples of Christmas sweets were processed. The presence of the above mentioned bacteria was monitored in Christmas sweets and genes encoding toxin production were the presence of bacteria was detected.
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Biofilm formation in probiotic cultures and its application in pharmacy
Ryšávka, Petr ; Obruča, Stanislav (referee) ; Vorlová, Lenka (referee) ; Márová, Ivana (advisor)
The work was comprehensively focused on the development of adhesive forms of probiotics in the form of a biofilm on combined carriers with a prebiotic component. The second part dealed with the influence of food on the multiplication and survival of selected types of probiotic bacteria. Subsequently, the effect of individualized probiotic supplements on changes in the human intestinal microbiome was monitored. Suitable adherent probiotic strains for biofilm formation were selected and tested. Methods have been introduced and different variants of carriers for culturing and binding bacteria have been tested. In vitro experiments verified the stability of biofilm stucture and its resistance to low pH, bile and antibiotics in comparison with the planktonic cell form. The antimicrobial effect of probiotic strains in the form of a biofilm was studied. The cultivation of the multispecies biofilm on the combined carrier was optimized and the stability of the biofilm and the final viability of probiotic bacteria were confirmed. Furthermore, the influence of various foods and beverages on the viability of probiotic bacteria was evaluated with emphasis on the simulation of passage through the gastrointestinal tract. Both models, solutions with standardised concentrations of alcohol, sugar, salts, proteins or different pH and different types of real foods and beverages were tested. The effect of food and beverages was tested on monocultures of Lactobacillus acidophilus, Bifidobacterium breve and on probiotic capsules containing a mixed culture of probiotic microorganisms. The survival of probiotics in various food matrices in the simulated gastrointestinal tract was quantitatively different. We managed to define foods suitable for supporting the multiplication of probiotic bacteria. A separate part of the work was focused on the targeted modulation of the intestinal microbiome by individualized probiotics that were prepared on the basis of molecular biological analyzes of the intestinal microbiome aimed at detecting the percentage of lactobacilli, bifidobacteria and phylum Firmicutes and Bacteroidetes. Personalized probiotic supplementation confirmed the positive effect of this approach on microbiome changes, especially on the increase of the content of lactobacilli, bifidobacteria and the overall diversity of the microbiome.
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Characterization of selected yeast strains from the environment
Bečková, Alena ; Omelková, Jiřina (referee) ; Vránová, Dana (advisor)
The aim of this bachelor thesis deals with identification type-yeasts, which were obtained from the Culture Collection SAV in Bratislava. The purpose is extension of yeast database in laboratory of Faculty of Chemistry, which is used by identification yeasts in samples taken from food or environment. Identification of yeasts was implemented by method PCR-RFLP. Obtained segment is located in area 5,8S-ITS and is defined by using primers ITS1 and ITS4. Restriction analysis was carried out by restriction endonucleasis HaeIII, HinfI, HhaI and TaqI. Chosen species were also tested for presence of extracellular lipasis. In this part of characterisation was used SpiritBlue Agar. The presence of blue colour is lost by activity of lipasis.
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Characterization of carotenogenic yeasts using molecular techniques
Kostovová, Iveta ; Čarnecká, Martina (referee) ; Márová, Ivana (advisor)
The aim of this master’s thesis was focused on characterization of carotenogenic yeast using molecular techniques. 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, which approved differences of S. roseus in all analyzed rDNA sequencies compared to the other analyzed carotenogenic yeasts. Parameters of PFGE and isolation procedure of the intact DNA were optimized for caryotypic yeast characterization. At all, nine of carotenogenic yeast strains Rhodotorula, Sporobolomy-ces, Cystofilobasidium a Phaffia were analyzed by this techniques. Further part of this thesis was focused to application of molecular methods to analysis of region D1/D2 of large ribosomal subunit in mutant carotenogenic yeast strains. Mutant strains were pre-viously adapted to waste substrates - pasta and glycerol, and stability of their production properties was verified.
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Influence of matrix type on the authentication of foodstuffs containing fruits
Kopková, Pavlína ; Strečanská, Paulína (referee) ; Fialová, Lenka (advisor)
Certain types of food, mainly the more expensive ones, are often adulterated to reduce their manufacturing price. However, this reduces their quality and can also have a negative impact on the health of the consumer. Children's fruit products are also targeted by fraudulent producers, where the declared fruit is most often replaced by a cheaper version. This work focuses on the detection of adulterated foods using various analytical methods, in particular PCR. The theoretical part focuses on the issue of food adulteration, the analytical methods used for detecting adulteration, and also on mango and banana which are determined in this work. The aim of this thesis was to determine what effect the type of matrix has on the determination of fruit components in food by PCR. Three types of matrix were used for this purpose - fruit puree, smoothie, and bars. An important task was to optimize the DNA isolation to achieve adequate purity and concentration of DNA. Then, the amplifiability of the obtained DNA was verified. The DNA isolates were then analyzed by multiplex PCR with primers specific for mango and banana. The results were verified by agarose gel electrophoresis. Subsequently, it was possible to determine that the fruit component in bars and fresh smoothies was the most easily analyzed by PCR and, on the contrary, the determination was problematic for puree. The instrumental part was focused on the determination of phenolic compounds in the products by HPLC. For this purpose, optimization of the extraction of phenolic compounds was necessary. This method was able to detect the presence of mangoes in all samples.
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Probiotics and prebiotics in food and other products
Langová, Denisa ; Havlíková, Šárka (referee) ; Trachtová, Štěpánka (advisor)
Theoretical part of this thesis focuses on present state and research of probiotics and prebiotics, their use for microflora modulation of host and their beneficial effects on the health of individuals. Furthermore thesis deals with efficiency of probiotics strains, which depends on the food matrix and other various factors. The experimental part focuses on the identification of chosen bacterial strain, which is contained in probiotics product. It is realized due the isolation of bacterial DNA by phenol extraction and by use of magnetic particles and subsequent analysis of obtained DNA by polymerase chain reaction (PCR).
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Magteic particles and their applications in biotechnology
Knápková, Monika ; Konečná, Jana (referee) ; Trachtová, Štěpánka (advisor)
The thesis is focused on the magnetic particles which are used in several biotechnological applications. The theoretical part deals with the specific properties of these nanoparticles and materials of which the nanoparticles can be made. There are also mentioned some of the biotechnological applications of magnetic particles. During the experimental part, selected types of magnetic particles were used to isolate nucleic acid. The quality of the isolated DNA with respect to purity was evaluated using the polymerase chain reaction and its modifications. High resolution analysis (HRM analysis) was also used to verify the quality of the isolated DNA and to resolution Lactobacillus casei and Lactobacillus rhamnosus. DNA isolation using magnetic carriers was successful. Commercially available MPG microcarriers and magnetic microparticles Fkol 77ox were the most suitable. In terms of purity magnetic nanoparticles F79/L3-PLL were the most suitable for the DNA isolation. The resolution of bacterial strains of Lactobacillus casei and Lactobacillus rhamnosus was not successful.
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