|
|
Probiotics and prebiotics and their co-encapsulation
Šnajdarová, Karolína ; Bokrová, Jitka (referee) ; Márová, Ivana (advisor)
This bachelor thesis is focused on study of probiotic cultures and options of coencapsulation with specific substrates called prebiotics. Lactobacillus acidophilus and Bifidobacterium breve were used as encapsulated microorganisms. As the specific substrates inulin, psyllium, apple fiber and hemp fiber were tested. Prebiotics was added to probiotics both in untreated form and in hydrolyzed form. The stability and viability of the cells have been studied by microscopy for the period of 6 weeks. Particles were stored in the enviroment of 2.5% citric acid. As the best substrate for cell growth the hemp fiber was found. The hemp fiber exhibited the highest increase of cells count. During observation of long-term stability in the model digestive conditions, particles with hemp fiber were destroyed in instestinal juices. For that reason, particles with hemp fiber could be used in food supplements with targeted transport. The bachalor thesis is also focused on characterisation of prebiotics components. The highest amount of total sugars in the group of non-hydrolyzed prebiotics exhibited psyllium. The highest content of reducing sugars both in the groups of non-hydrolyzed and hydrolyzed prebiotic had hemp fiber. By the method of thin-layer chromatography was found out that the main components of hydrolyzed prebiotics are glucose and fructose. Further, some disaccharides and oligosaccharides were obtained by TLC analysis. For characterisation of prebiotics by HPLC the column Rezex exhibited better sensitivity. HPLC analysis confirmed that the main components of prebiotics are glucose and fructose, some more complex carbohydrates were found too.
|
|
|
Identification of probiotic bacteria in complex food matrices and dietary supplements
Cesnak, Filip ; Konečná, Jana (referee) ; Trachtová, Štěpánka (advisor)
Theoretical part of the thesis deals with the general characteristics of probiotic bacteria, their effect on human health and with technological demands imposed on them. Furthermore the thesis deals with actual methods of bacterial identification, especially on the base of polymerase chain reaction. Presence of the declared probiotic bacteria was analysed with the polymerase chain reaction (PCR) and the DNA was isolated from the sample of food additive with the use of magnetic particles.
|
|
|
Probiotics in food products
Silná, Renata ; Trachtová, Štěpánka (referee) ; Španová, Alena (advisor)
Probiotics are living microorganisms with a positive effect on the consumer when they are added to food in adequate amount. The best known probiotic are lactic acid bacteria and yeast Saccaromyces cerevisiae var. boulardii. The theoretical part of the thesis is focused on using probiotics microorganisms in food. In the experimental part of the thesis were prepared crude lysates from three food products and the presence of bacterial DNA was proved by PCR method.
|
|
|
Recombinant probiotics
Surá, Tereza ; Rittich, Bohuslav (referee) ; Španová, Alena (advisor)
Theoretical part of this thesis focuses on present state and research of recombinant probiotics and their use in food industry and health care. It also concentrates on their beneficial effects on the health of individuals. The experimental part focuses on the identification of specific bacterial strain in a probiotics food supplements. The DNA was isolated from these products by use of magnetic microparticles and obtained DNA was subsequently analysed through polymerase chain reaction.
|
|
|
Probiotics and prebiotics - a study of interactions, effects and co-encapsulation
Vrtná, Monika ; Němcová, Andrea (referee) ; Márová, Ivana (advisor)
This diploma thesis is focused on encapsulation probiotics and co-encapsulation with some types of prebiotics. In theoretical part is aimed to probiotics, their general characteristics and application of probiotics in food industry. There are described prebiotics and their classification, there is described principles of encapsulation and encapsulation techniques. Methods, which are used for analysis of particles and encapsulation components were introduced too. The experimental part describes methods of prebiotics characterization by high performance liquid chromatography, thin layer chromatography and spectrophotometric methods. Cultivation of probiotics with prebiotics - hydrolyzed and non-hydrolyzed wad tested. Using flow cytometry cell viability was measured too. Finally probiotics and prebiotics were encapsulated, mainly by encapsulator machine. Long-term stability of particles during 6 week storage was observed. The particles were exposed to effect of artificial intestinal, gastric and bile juices.
|
|
|
The analysis of DNA isolated from different types of probiotic products using real-time PCR and HRM analysis
Sedláková, Lucie ; Rittich, Bohuslav (referee) ; Trachtová, Štěpánka (advisor)
The aim of this diploma thesis was to introduce real-time PCR with high-resolution melting analysis for Bifidobacterium species. Currently a small number of publication, dealing with identification of Bifidobacterium species using high-resolution melting analysis, is available. According to publications dealing with identification of lactic acid bacteria were selected primers P1V1 and P2V1, LAC1 and LAC2, LsppUPF and LsppUPR, V3F and V3R, V6F and V6R. Using this primers bacterial DNA was amplified by real-time PCR with high-resolution melting analysis. After evaluation of the measured results efficiency of selected primers was verified on DNA izolated from complex sample of probiotic product. After further optimisation real-time PCR with high-resolution melting analysis could be suitable using selected primers for Bifidobacterium species.
|
|
|
The used of magnetic microparticles for isolation and prove of probiotic bacterial DNA in meat
Vašíček, Roman ; Rittich, Bohuslav (referee) ; Španová, Alena (advisor)
This thesis deals with the isolation of probiotic DNA from meat products and its assesment by PCR methods. In this thesis is developed homogenization of samples of sausages with kopist, preparation of sausage cells lysates and isolation of DNA by using of magnetic microparticles. The DNA was isolated from sausage lysates by using magnetic microparticles. Isolated DNA was further amplified in genus and spesies-specific PCR methods. In tested products was proven presence of DNA of domain Bacteria, type Lactobacillus and Bifidobacterium. In one product was proven presence of species Lactobacillus acidophilus and Bifidobacterium animalis.
|
|
|
Encapsulation of selected natural extract for food application.
Vyskočilová, Terezie ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
This diploma thesis deals with encapsulation of natural extracts. In the theoretical part the methods of encapsulation, materials for particle preparation, as well as application of encapsulation techniques in food industry were described. In experimental part selected natural extracts of propolis, green barley and probiotics were characterized. There substances were encapsulated into alginate and chitosan. In the total of 25 types of prepared particles long-term stability in some model physiological conditions as well as in four different model foods was evaluated. Additionally, stability of selected particles in several real milk-based products was followed too. The stability of particles was determined spectroptohometrically. In natural extract a content of polyphenols, proteins, chlorophylls, as well as total antioxidant activity were analysed. To analysis of probiotics optical and fluorescence microscopy were used. In propolis and green barley antimicrobial activity was tested too. Moreover, in the sample of propolis also cytotoxic assay was applied. Agar-chitosan was chosen as the best shell material for propolis due to its optimal stability in model physiological conditions as well as model foods. Liposomes were evaluated as unstable and were not recommended for further application. As the suitable shell material for powdered green barley starch-alginate (rate 1:4) and agar-chitosan were proposed, while the second one showed better stability for released proteins. Agar-chitosan shell material was usable for fresh green barley too. For probiotics encapsulation alginate or alginate-starch were chosen because of their porosity and possibility of nutrients diffusion. In real foods the best results were reached with application of probiotic particles into milk. Coencapsulation of powdered barley and probiotics did not confirm inhibition of culture growth. Neither the antimicrobial effect of propolis and barley nor the cytotoxic effect of propolis were confirmed.
|
|
|
Isolation of PCR-ready DNA from probiotic products for baby nutrition
Mantlová, Gabriela ; Havlíková, Šárka (referee) ; Španová, Alena (advisor)
The aim of thesis is focused on isolation of DNA in quality for polymerase chain reaction (PCR) and the identification of probiotic bacteria. From six probiotic supplements for children were isolated PCR-ready DNAs using magnetic carriers P(HEMA-co-GMA). Isolated DNA was amplified by genus-specific and species-specific primers. DNAs of Lactobacillus, Bifidobacterium and Streptococcus genera were identified as: L. acidophilus, L. rhamnosus, L. casei, B. bifidum, B. longum ssp. longum, B. breve, B. longum ssp infantis, B. animalis and S. thermophilus. The identification corresponded with the data declared by the producers.
|
|
|
Identification of bacteria of Lactobacillus acidophilus species in probiotic products
Sznapková, Veronika ; Trachtová, Štěpánka (referee) ; Španová, Alena (advisor)
Probiotic lactic acid bacteria (LAB) are an important part of fermented dairy products, pharmaceuticals and food supplements. At present, rapid and accurate identification of bacteria is carried out using molecular biological methods based on DNA amplification. The aim of the thesis was to identify by non-cultivation bacteria of genus Lactobacillus and bacteria of species Lactobacillus acidophilus in complex matrices at total of seven different food supplements. Total DNA was isolated from crude cell lysates using magnetic carrier P(HEMA-co-GMA). Amplificability of DNA was verified by PCR using primers specific for the domain Bacteria. In next step isolated DNA was amplified using primers specific for the genus Lactobacillus and species Lactobacillus acidophilus to demonstrate the presence of this bacterial genus and species declared by the producers. The results of bacteria identification obtained by PCR were compared with declared specification given by the producers.
|
guest ::
