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Addition of probiotics to baby food products
Dudrová, Markéta ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
This Diploma thesis deals with preparation of probiotic cultures Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium breve enriched with prebiotics meant for application in baby food products. Natural extracts from matcha, moringa, young beat, young barley, chlorella and spirulina were selected as prebiotics. The theoretical part is focused on probiotic bacteria, their biological effects and their effects on the child´s body. The experimental part deals with the cultivation of probiotic bacteria with plant extracts, monitoring their viability and stabilization in an encapsulated form. Mixtures of probiotic cells with prebiotics were encapsulated into alginate particles to increase stability. Some of the alginate particles were processed by freeze drying. Mixtures of probiotic cultures with plant extracts were subjected to model human digestion by the action of model digestive juices in unencapsulated, encapsulated and lyophilized form. Selected extracts of plant materials were characterized in terms of amount of total and reducing sugars, total phenolic substances, individual phenolic substances and antioxidant activity. Further, two baby commercial dietary supplements containing probiotics were selected, which were characterized in terms of cell number and viability. Probiotic products were also subjected to model digestion.
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Preparation of food supplements for children containing probiotic bacteria and fruit components
Vetchá, Vendula ; Bendová, Agáta (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis is focused on the preparation of supplementary food with probiotic culture and fruit components. The aim of this work was to determine which of the selected extracts will affect the growth of probiotics and also will contain a certain proportion of phenolic compounds, flavonoids, vitamin C and show antioxidant effects. The theoretical part of the work is focused on the intestinal microbiota, the issue of probiotics and the characterization of encapsulation methods of probiotics. We used extracts of teas and fruit syrups in the experimental part. The antimicrobial activity against model microorganisms Escherichia coli, Micrococcus luteus, Staphylococcus epidermidis and Serratia marcescens was analyzed. Interaction of probiotic bacteria Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium breve in extracts were tested. After model digestion, cell viability of probiotic bacteria in combination with extracts was examined during and after digestion. In the last part, encapsulated particles containing probiotics and a mixture of tea and syrup were prepared.
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Use of encapsulation techniques for production of food for infants
Hoová, Julie ; Čarnecká, Martina (referee) ; Skoumalová, Petra (advisor)
The Diploma thesis deals with use of selected probiotic strains Lactobacillus acidophilus and Bifidobacterium breve in different forms in food for infants. The theoretical part is focused on describing probiotics, encapsulation methods and intestinal gut microbiota of infants. Further, characterization of individual periods of infant feeding and food for infants were introduced. In experimental part the possibilities of encapsulation and lyophilisation of probiotic cells were observed. Probiotic cells were encapsulated into alginate particles. The encapsulator was used for preparation of particles and the most appropriate particles were prepared by encapsulation nozzle with size of 300 µm. Moreover, probiotics viability was monitored by Flow Cytometry, Fluorescence Microscopy and by cultivation (CFU method). Viability of probiotics was monitored during long-term storage in selected food for infants. The appropriate shelf life of non-lyophilized alginate particles in real food have been set at 1 to 2 months. Lyophilized alginate particles could be stored for more than 3 months. Finally, the stability of the particles and viability of encapsulated and non-encapsulated cells in the gastrointestinal tract conditions were also examined. The viabilities of lyophilized cells and cells encapsulated in lyophilized particles were also compared. From the results obtained, non-encapsulated probiotic bacteria cells are more susceptible to negative effects of digestive juices, the percentage of dead probiotic cells after digestion was approximately 80 %. On the other hand, alginate particles showed cell protection from digestive juices, after incomplete cell releasing from particles the percentage of dead probiotic cells did not exceed 20 %. After adequate rehydration, similar results were gained with lyophilized alginate particles. Lyophilized alginate particles have been determined to be the most suitable application form for infants’ food.
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Preparation and characterization of nanoparticles with encapsulated antimicrobial component
Dohnalová, Marie ; Strečanská, Paulína (referee) ; Márová, Ivana (advisor)
This bachelor thesis is focused on the preparation and characterization of particles with encapsulated natural substances with antioxidant and antimicrobial properties. Selected antioxidants were anthocyanins, eugenol and vitamin E, as one of the most powerful antioxidants. At the same time, antimicrobial agents were chosen, in this case eugenol. In the theoretical part, individual active substances, materials for the preparation of particles, methods of their preparation were characterized and the principle of determining the safety of used materials. In the experimental part, selected active substances were characterized and the preparation of particles was optimized. Two types of liposomes were prepared, for which the encapsulation efficiency, size and stability were determined. Also prepared aqueous extracts of blueberries and blackberries were prepared, for which total anthocyanin content has been determined. The extracted substances from the plant material were encapsulated into alginate particles. Furthermore, the gradual release of active substances from particles into model environments using a spectrophotometer was determined. During the gradual release of active substances from the particles, the antioxidant effect was also monitored, in which it was possible to observe a decrease with the passage of time. The antimicrobial effect of active substances and liposomes against model microorganisms Escherichia coli and Micrococcus luteus was also tested. Cytotoxicity tests on human keratinocytes were performed on selected active substances, extracts and prepared nanoparticles, where it was proven that the selected materials are non-cytotoxic. Finally, a proposal for a possible application form in the form of an alginate hydrogel was created.
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Addition of probiotics to baby food products
Dudrová, Markéta ; Skoumalová, Petra (referee) ; Márová, Ivana (advisor)
This Diploma thesis deals with preparation of probiotic cultures Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium breve enriched with prebiotics meant for application in baby food products. Natural extracts from matcha, moringa, young beat, young barley, chlorella and spirulina were selected as prebiotics. The theoretical part is focused on probiotic bacteria, their biological effects and their effects on the child´s body. The experimental part deals with the cultivation of probiotic bacteria with plant extracts, monitoring their viability and stabilization in an encapsulated form. Mixtures of probiotic cells with prebiotics were encapsulated into alginate particles to increase stability. Some of the alginate particles were processed by freeze drying. Mixtures of probiotic cultures with plant extracts were subjected to model human digestion by the action of model digestive juices in unencapsulated, encapsulated and lyophilized form. Selected extracts of plant materials were characterized in terms of amount of total and reducing sugars, total phenolic substances, individual phenolic substances and antioxidant activity. Further, two baby commercial dietary supplements containing probiotics were selected, which were characterized in terms of cell number and viability. Probiotic products were also subjected to model digestion.
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Preparation of food supplements for children containing probiotic bacteria and fruit components
Vetchá, Vendula ; Bendová, Agáta (referee) ; Skoumalová, Petra (advisor)
This bachelor thesis is focused on the preparation of supplementary food with probiotic culture and fruit components. The aim of this work was to determine which of the selected extracts will affect the growth of probiotics and also will contain a certain proportion of phenolic compounds, flavonoids, vitamin C and show antioxidant effects. The theoretical part of the work is focused on the intestinal microbiota, the issue of probiotics and the characterization of encapsulation methods of probiotics. We used extracts of teas and fruit syrups in the experimental part. The antimicrobial activity against model microorganisms Escherichia coli, Micrococcus luteus, Staphylococcus epidermidis and Serratia marcescens was analyzed. Interaction of probiotic bacteria Lactobacillus acidophilus, Lactobacillus casei and Bifidobacterium breve in extracts were tested. After model digestion, cell viability of probiotic bacteria in combination with extracts was examined during and after digestion. In the last part, encapsulated particles containing probiotics and a mixture of tea and syrup were prepared.
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Use of encapsulation techniques for production of food for infants
Hoová, Julie ; Čarnecká, Martina (referee) ; Skoumalová, Petra (advisor)
The Diploma thesis deals with use of selected probiotic strains Lactobacillus acidophilus and Bifidobacterium breve in different forms in food for infants. The theoretical part is focused on describing probiotics, encapsulation methods and intestinal gut microbiota of infants. Further, characterization of individual periods of infant feeding and food for infants were introduced. In experimental part the possibilities of encapsulation and lyophilisation of probiotic cells were observed. Probiotic cells were encapsulated into alginate particles. The encapsulator was used for preparation of particles and the most appropriate particles were prepared by encapsulation nozzle with size of 300 µm. Moreover, probiotics viability was monitored by Flow Cytometry, Fluorescence Microscopy and by cultivation (CFU method). Viability of probiotics was monitored during long-term storage in selected food for infants. The appropriate shelf life of non-lyophilized alginate particles in real food have been set at 1 to 2 months. Lyophilized alginate particles could be stored for more than 3 months. Finally, the stability of the particles and viability of encapsulated and non-encapsulated cells in the gastrointestinal tract conditions were also examined. The viabilities of lyophilized cells and cells encapsulated in lyophilized particles were also compared. From the results obtained, non-encapsulated probiotic bacteria cells are more susceptible to negative effects of digestive juices, the percentage of dead probiotic cells after digestion was approximately 80 %. On the other hand, alginate particles showed cell protection from digestive juices, after incomplete cell releasing from particles the percentage of dead probiotic cells did not exceed 20 %. After adequate rehydration, similar results were gained with lyophilized alginate particles. Lyophilized alginate particles have been determined to be the most suitable application form for infants’ food.
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