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Development of probiotic dietary supplement
Krahulcová, Aneta ; Vítová, Eva (referee) ; Vránová, Dana (advisor)
The thesis deals with a theme of probiotic mikroorganisms which are aplicated as a dietary supplement. Health benefit on the host have been known for a long time, however, there might be some negative effects affecting a consumer. In connection with this observation defining requirements and evaluating of safety of probiotics in food was necessary. The new probiotic dietary supplement can not be expanded on the market without these processes. Every strain must be tested separately on each property. The ability of rezistance against conditions inside human gastrointestinal tract belongs to the most basic tests. The aim of the practical part is testing this ability of rezistance in vitro by simulated conditions. The model of gastrointestinal juices was designed according to the Czechoslovak codex. The form contributes to the higher rezistance of probiotics within implementing to the host. Also a dosage form of probiotics was involved to a in vitro testing.
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Molecular identification of selected species of lactic acid bacteria and bifidobacteria in food additives
Riegelová, Kristýna ; Rittich, Bohuslav (referee) ; Španová, Alena (advisor)
Probiotic lactic acid bacteria and bifidobacteria are natural part of microflora of gastrointestinal tract. In the present, day they are grossly exploited in food processing industry. The aim of the work was molecular identification of bacteria of genus Lactobacillus and Bifidobacterium in complex matrices of two food additives. Total DNA was isolated from crude cell lysates by magnetic particles P(HEMA-co-GMA). Isolated DNA was amplified in genus-specific and species-specific PCRs. Amplicons were detected by agarose gel electrophoresis. Results were compared with declared specification given by producers in three different batches.
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Identification of probiotic Bifidobacterium strains in dairy products
Zovčáková, Monika ; Horák, Daniel (referee) ; Španová, Alena (advisor)
Lactobacilli are dominant bacteria of the vaginal flora. Lactobacillus-containing probiotics products are used for the treatement and profylaxis of bacterial urogenital infections. This work is focused on DNA identification and species identification of probiotic bacteria in 5 different vaginal tablets using molecular-genetic methods. Total DNA isolated from complex matrix of vaginal tablets was used for amplification in polymerase chain reaction. DNA was isolated from crude cell lysates by magnetic particles P(HEMA-co-GMA) and by method of phenol extraction. Identification of species of probiotic bacteria was verified using genus-specific and species-specific PCRs. Results of bacterial identification obtained by PCR were compared with declared specification given by producers. Bacteria of genus Lactobacillus were proved in all tablets whereus species identification was in accordance with the stated composition in 1 tablet only.
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Identification of selected genes in lactic acid bacteria
Kristová, Mária ; Vojtíšková, Marie (referee) ; Španová, Alena (advisor)
Lactic acid bacteria are natural habitants of human gastrointectinal tract. Among the most important are bacteria of genus Lactobacillus and genus Bifidobacterium that contain a lot of probiotic species. Probiotic species are used as food supplements. This work was focused on DNA separation from crude cell lysates of 4 food supplements using magnetic carrier P(HEMA-co-GMA) covered by carboxyl groups. DNA was reversible adsorbed to the carriers in the presence of PEG 6000 (16%) and NaCl (2 M) (final concentrations) and eluted into TE buffer. Lysis of cells from food supplements was performed by lysozyme, SDS and proteinase K. The amount of lysozyme was optimalized. Concentration of separated DNA was measured by spectrophotometric method. The amount of isolated DNA was suitable for PCR. Isolated DNA was used for PCR with universal primers, PCR specific for genus Lactobacillus and genus Bifidobacterium and for 9 different species-specific PCRs: Lactobacillus rhamnosus, Lactobacillus acidophilus, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus casei/paracasei, Streptococcus thermophilus, Bifidobacterium longum, Bifidobacterium bifidum and Bifidobacterium infantis. Amplicons were detected by agarose gel electrophoresis (1,8%). It was shown that DNA amplification methods are quick and precise for identification of studied species. The results of bacteria identification were compared with data provided by the manufacturer. In all food supplements, bacteria of genus Lactobacillus and Bifidobacterium were detected. However, only some species provided by manufacturer were identified by PCR in each tablet.
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DNA isolation from probiotic lactic acid bacteria in food additives
Tvrdíková, Jana ; Vojtíšková, Marie (referee) ; Španová, Alena (advisor)
In this work the functionalised magnetic particles were tested with streptavidin to selective DNA isolation. The method of selective DNA isolation was tested by using DNA probiotic strain Lactobacillus paracasei subsp. paracasei CCDM 211/06. A test was done on the biotinyl oligonucleotic particles, which was immobilised by containing streptavidin and it was used like a DNA probe for isolation complementary DNA chain by means of DNA/DNA hybridization. The primer R 5´ bio and the biotinyl denatured specific PCR product were tested for species Lb. paracasei as a DNA probe. These following experimental conditions were optimized for selective DNA isolation: temperature and time of hybridization, amount of DNA and the release of DNA from microspheres. Isolation of DNA was verified by PCR with specific generic primers. The specific generic PCR product was amplified in extent 250 bp, which was detected by using electrophoresis in agarose gel. This optimized method was successfully used in selective isolation of DNA Lactobacillus from a complementary sample of supplementary food (BIFI pangamin).
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Fermentation of different cereals by the probiotic bacteria Lactobacillus plantarum 299v
Hamalová, Sabina ; Španová, Alena (referee) ; Prof.Siv Ahrne (advisor)
Počet obyvatel trpících různými infekčními, zánětlivými a alergickými nemocemi stejně jako výskyt laktózové nesnášenlivosti a vysoké hodnoty krevního cholesterolu, má narůstající tendenci. Některé z těchto zdravotních problémů jsou způsobeny nevyváženou střevní mikroflorou. Probiotika jsou pak chápána (nejen) jako potravní komponenty, které přispívají k ustanovení mikrobiální rovnováhy (Parker, 1974) mezi zdraví prospěšnými a škodlivými bakteriemi. Z tohoto důvodu, terapie založená na podávání probiotik pacientům přitáhla zájem ze strany vědců. Vhodný probiotický kmen se pak volí v závislosti na požadovaném zdravotním účinku (příp. zdravotním problému, který má být probiotickou terapií léčen). Lactobacillus plantarum 299v již prokázal své blahodárné účinky na lidech a zároveň byla i potvrzena jeho zdravotní bezpečnost, díky čemuž může tato bakterie být kategorizována jako probiotický kmen (Probi AB, Sweden). I díky tomu je Lactobacillus plantarum 299v ve značné oblibě přidáván do mnoha fukčních potravin a prodáván na trhu pod různými jmény, probiotický nápoj ProViva je jedním takovým příkladem. Cílem této práce bylo studovat fermentační proces na žitném, ječmenném a sojovém substrátu pomocí kmene Lactobacillus plantarum 299v, přičemž zvýšená pozornost byla věnována právě soji a ječmeni jako potenciálně novým substrátům pro výše uvedenou bakterii. Hlavními záměry bylo zkoumání růstu a metabolické aktivity bakterie Lactobacillus plantarum 299v v asociaci s různými cereálními substráty, a později bylo studováno totéž také ve směsi fermentované cereální komponenty s běžně dostupným ovocným džusem. K tomu, aby se dosáhlo optimálních podmínek fermentace, je třeba vzít v úvahu několik aspektů. Hlavní role při konceptování nového fermentovaného produktu patří především zpracování a taktéž kompozici surového materiálu, růstové kapacitě a produktivitě bakteriální kultury a stabilitě finálního produktu během skladování (De Vuyst, 2000). Tyto parametry jsou důležité hlavně ze strany výrobců. Krom toho jsou tu ale i zákazníci, pro něž je přijatelnost produktu založena z velké části na organoleptických vlastnostech finálního probiotického produktu, tj. aromatu a chuti. Přítomnost a dostupnost různých jednotlivých nutrientů, která byla obsažena ve fermentačním médiu výsledkem rozdílných použitých cereálních substrátů, pravděpodobně vyústila v odlišnosti metabolických drah, což pak později mohlo způsobit rozdíly v organoleptických vlastnostech finálního produktu.
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Probiotics in food products for children
Vozárová, Petra ; Kvasničková, Eva (referee) ; Španová, Alena (advisor)
Despite of the high level of science and medicine, people are trying to return to the nature and use it for their lives. For example, they are using probiotics, which are live cultures able to reside in the human intestine and there can start their role. The teoretical part of this bachelor thesis deals with probiotic bacteria, their properties and those properties which are important in the food industry and the main part focuses on the probiotics used in baby food. The experimental part of the thesis targets on an analysis of two probiotic supplements for children (BioLac Baby and Probacílium+). There was a DNA isolated from these two products by method of phenol extraction and using magnetic media. The whole DNA isolated from these products was amplificated by genus-specific PCR.
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Microbiological analytical methods suitable for dairy industry
Vlasák, Jaroslav ; Illková, Kateřina (referee) ; Trachtová, Štěpánka (advisor)
The theoretical part of the thesis is focused on probiotics in dairy products. Thesis deals with molecular genetic methods, which are used to analyze DNA. Especially are discussed methods used for isolation bacterial cells belonging to genus Lactobacillus. The polymerase chain reaction (PCR) is the basic technique at present time. Short chain of oligonucleotide primers are used to amplification specific parts of DNA molecule chain. The practical part of the thesis is focused on the DNA from pure bacterial culture and probiotic dairy product. DNA was isolated using methods of phenol-chloroform extraction and magnetic separation. For magnetic separation was used magnetics particles covered with carbonyl functional groups. Quality of the DNA was confirmed by PCR amplification. Primers specific for domain Bacteria and genus Lactobacillus and Bifidobacterium was used.
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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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Encapsulation of lactic acid bacteria
Vrtná, Monika ; Lichnová, Andrea (referee) ; Márová, Ivana (advisor)
This bachelor thesis is focused on encapsulation of two strains of probiotic bacteria. Lactic acid bacteria were encapsulated into several types of materials, mostly polysaccharides. The theoretical part describes the techniques of encapsulation applicable in the food industry. During the experimental part alginate and chitosan microparticles were prepared. These particles exhibited different sizes and some of them were modified by starch and carboxymethyl cellulose. Particles were used for encapsulation of two strains - Bifidobacterium breve and Lactobacillus acidophilus. Using flow cytometry cell viability was measured after 24-hours cultivation of bacteria. Particles were observed immediately after encapsulation by optical microscopy and then long-term stability in model foods was evaluated after two days, a week and after four weeks of incubation. Using the Bürker chamber the alived and death bacteria were counted inside and outside the capsule. The stability and viability of the cells were studied also in the artificial intestinal, stomach and bile juices. As the best material for encapsulation of lactic acid bacteria 2% alginate modified by carboxymethyl cellulose was found. The highest viability of bacteria was observed in milk as the real model food. Prepared particles are suitable for use in the food industry.
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