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Analysis of selected biologically active substances in cereal products
Skutek, Miroslav ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
Presented diploma thesis was focused on study of biologically active compounds, especially some sugars in cereal products. In experimental part the total of 29 different cereal materials, food industry waste products and natural complex matrixes (microbial polysaccharide, honey, beer) were used. As a part of this work optimization of analytical methods suitable for analysis of simple sugars, oligo- and polysaccharides was done. In cereal samples reduced and neutral sugars were analyzed spectrophotometrically and individual sugars were detected by chromatography. For HPLC/RI analysis optimal mobile phase composition and chromatography conditions were proposed. For mono- a oligosaccharides C18-NH2 sorbent, mixture acetonitril:water 75:25 as mobile phase and flow 1 ml/min were verified as suitable separation parameters. Thin layer chromatography of mono- and oligosaccharides was optimized too. Introduced chromatography and spectrophotometry methods were then applied to analysis of cereal samples. As a model sugar natural microbial polysaccharide pullulan was used to analytical method testing. In cereal products and food matrixes total neutral and reduced sugars as well as products of their acid and enzyme hydrolysis were measured. Detailed analysis of some glycoside composition was tested too. As the most usable method for both qualitative and quantitative analysis of cereal sugars HPLC/RI method was found. To detailed identification of malto-oligosacharides tandem LC/MS/MS technique using derivatization by 1-phenyl-3-methyl-5-pyrazolon was tested too.
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Determination of honey authenticity and adulteration by anion exchange chromatography
Ždiniaková, Tereza ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Cieľom tejto diplomovej práce je stanoviť kvalitu a zloženie medu, taktiež stanoviť jeho botanický pôvod na základe profilu sacharidov v mede. Med je prírodný produkt vysokej kvality a vďaka značnej spotrebe a nemalej trhovej hodnote je tiež terčom na falšovanie. S cieľom identifikovať podvody a cudzorodé látky, pochádzajúce z cukrových sirupov, boli analyzované oligosacharidy a polysacharidy na báze maltodextrínov. Teoretická časť popisuje chemické zloženie medu a hlavné princípy aplikovanej inštrumentálnej techniky. Poskytuje literárny prehľad existujúcich analytických metód na stanovenie sacharidov prítomných v mede a na odhalenie jeho falšovania. Boli definované hlavné body falšovania a autenticity, vrátane legislatívnych aspektov a opisu bežných druhov falšovania. Experimentálna časť obsahuje postupy, ktoré vedú k vývoju a optimalizácii chromatografických podmienok a parametrov elektrochemického detektora na stanovenie sacharidov a maltodextrínov (oligosacharidov a polysacharidov) vo vzorkách medu. Použitá analytická technika bola vysoko účinná aniónovo-výmenná chromatografia (HPAEC) spojená s pulzným amperometrickým detektorom (PAD). Vyvinutá a optimalizovaná chromatografická metóda bola taktiež validovaná z hľadiska linearity, dynamického rozsahu, analytických limitov, presnosti a správnosti. Na záver bola táto vypracovaná metóda úspešne zhodnotená analýzou autentických a falšovaných vzoriek medu rôzneho botanického pôvodu pochádzajúcich z členských štátov EÚ.
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New fungal fucosidases and their synthetic potential
Glozlová, Michaela ; Beránek, Martin (advisor) ; Matoušková, Petra (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Michaela Glozlová Supervisor: prof. PharmDr. Martin Beránek, Ph.D. Consultants: doc. RNDr. Pavla Bojarová, Ph.D., Mgr. Pavlína Nekvasilová Title of diploma thesis: New fungal fucosidases and their synthetic potential The literary research focuses on α-L-fucosidases, their occurrence, functions, and use in the synthesis of fucosylated compounds, which were also a part of the research, particularly their presence in the human body and involvement in pathological conditions. Furthermore, it explores the oligosaccharides found in human milk, their impact on infant health, and their synthesis, which can be facilitated through the use of α-L-fucosidases. The experimental section involves the analysis of a library of filamentous fungi with the aim of identifying a representative strain with α-L-fucosidase activity towards pNP-α-L-fucoside. Recombinant α-L-fucosidases were selected based on searches in genetic databases and prepared. The feasibility of their production in Pichia pastoris and Escherichia coli was tested, and the produced enzymes were purified by ion exchange chromatography, characterized and their regioselectivity and synthetic potential for the synthesis of fucosylated...
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New fungal fucosidases and their synthetic potential
Glozlová, Michaela ; Beránek, Martin (advisor) ; Matoušková, Petra (referee)
Charles University Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Michaela Glozlová Supervisor: prof. PharmDr. Martin Beránek, Ph.D. Consultants: doc. RNDr. Pavla Bojarová, Ph.D., Mgr. Pavlína Nekvasilová Title of diploma thesis: New fungal fucosidases and their synthetic potential The literary research focuses on α-L-fucosidases, their occurrence, functions, and use in the synthesis of fucosylated compounds, which were also a part of the research, particularly their presence in the human body and involvement in pathological conditions. Furthermore, it explores the oligosaccharides found in human milk, their impact on infant health, and their synthesis, which can be facilitated through the use of α-L-fucosidases. The experimental section involves the analysis of a library of filamentous fungi with the aim of identifying a representative strain with α-L-fucosidase activity towards pNP-α-L-fucoside. Recombinant α-L-fucosidases were selected based on searches in genetic databases and prepared. The feasibility of their production in Pichia pastoris and Escherichia coli was tested, and the produced enzymes were purified by ion exchange chromatography, characterized and their regioselectivity and synthetic potential for the synthesis of fucosylated...
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Determination of honey authenticity and adulteration by anion exchange chromatography
Ždiniaková, Tereza ; Diviš, Pavel (referee) ; Vespalcová, Milena (advisor)
Cieľom tejto diplomovej práce je stanoviť kvalitu a zloženie medu, taktiež stanoviť jeho botanický pôvod na základe profilu sacharidov v mede. Med je prírodný produkt vysokej kvality a vďaka značnej spotrebe a nemalej trhovej hodnote je tiež terčom na falšovanie. S cieľom identifikovať podvody a cudzorodé látky, pochádzajúce z cukrových sirupov, boli analyzované oligosacharidy a polysacharidy na báze maltodextrínov. Teoretická časť popisuje chemické zloženie medu a hlavné princípy aplikovanej inštrumentálnej techniky. Poskytuje literárny prehľad existujúcich analytických metód na stanovenie sacharidov prítomných v mede a na odhalenie jeho falšovania. Boli definované hlavné body falšovania a autenticity, vrátane legislatívnych aspektov a opisu bežných druhov falšovania. Experimentálna časť obsahuje postupy, ktoré vedú k vývoju a optimalizácii chromatografických podmienok a parametrov elektrochemického detektora na stanovenie sacharidov a maltodextrínov (oligosacharidov a polysacharidov) vo vzorkách medu. Použitá analytická technika bola vysoko účinná aniónovo-výmenná chromatografia (HPAEC) spojená s pulzným amperometrickým detektorom (PAD). Vyvinutá a optimalizovaná chromatografická metóda bola taktiež validovaná z hľadiska linearity, dynamického rozsahu, analytických limitov, presnosti a správnosti. Na záver bola táto vypracovaná metóda úspešne zhodnotená analýzou autentických a falšovaných vzoriek medu rôzneho botanického pôvodu pochádzajúcich z členských štátov EÚ.
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New cryoprotectives in preservation of potentially probiotic bacteria of Bifidobacterium genus using freeze-drying procedure
Vrabcová, Petra ; Killer, Jiří (advisor) ; Jakub, Jakub (referee)
The probiotic bacteria of the genus Bifidobacterium are especially used in the dairy and pharmaceutical industry. They are present in the form of viable cells in pro(syn)biotic fermented milk, dried and freeze-dried products for its positive effects on the health. Lyophilization represents one of the widely used methods for long-term preservation of bifidobacteria. The lyophilization process is challenging, but very needed, and for this reason it is still necessary to explore new cryo(lyo)protective substances, which protect the microbial cultures more effectively before the negative effects of cryopreservation and lyophilization.
The aim of the thesis was to test the various mixtures of substances containing specific oligosaccharides, which have prebiotic properties, from the point of view of their potential cryo(lyo)protective effect of lyophilization process. For the purposes of the study, twelve bifidobacterial strains of human and animal origin were selected. As a potential cryo(lyo)protectives were used solutions on the basis of 5x concentrated TPY medium with addition of FOS, 10% fructooligosaccharides (FOS) and the solution on the basis of porcine gastric mucin. Number of viable cells was determined in lyophilisates enriched by the concrete solutions in the time intervals (30 days, 3 months and 6 months) after lyophilization and compared with the control lyophilized samples (fresh cultures without the additive solutions). The potential cryo(lyo)protective effectiveness of 5x concentrated TPY medium solution has been demonstrated only in B. boum, B. breve, B. longum subsp. infantis a Bombiscardovia coagulans, where decreased the number of viable cells about four orders of magnitude. The potential cryo(lyo)protective effectiveness in 10% FOS solution was found only in B. thermacidophilum subsp. porcinum and Bombiscardovia coagulans, where was found half the number of viable cells. The highest potential cryo(lyo)protective effectiveness was observed for a solution on the basis of porcine gastric mucin. The highest number of viable cells was demonstrated in B. animalis subsp. lactis, B. boum, B. longum subsp. infantis, B. longum subsp. longum, B. pseudolongum subsp. globosum and B. thermacidophilum subsp. porcinum lyophilisates using this potential cryo(lyo)protective solution.
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Analysis of selected biologically active substances in cereal products
Skutek, Miroslav ; Kočí, Radka (referee) ; Márová, Ivana (advisor)
Presented diploma thesis was focused on study of biologically active compounds, especially some sugars in cereal products. In experimental part the total of 29 different cereal materials, food industry waste products and natural complex matrixes (microbial polysaccharide, honey, beer) were used. As a part of this work optimization of analytical methods suitable for analysis of simple sugars, oligo- and polysaccharides was done. In cereal samples reduced and neutral sugars were analyzed spectrophotometrically and individual sugars were detected by chromatography. For HPLC/RI analysis optimal mobile phase composition and chromatography conditions were proposed. For mono- a oligosaccharides C18-NH2 sorbent, mixture acetonitril:water 75:25 as mobile phase and flow 1 ml/min were verified as suitable separation parameters. Thin layer chromatography of mono- and oligosaccharides was optimized too. Introduced chromatography and spectrophotometry methods were then applied to analysis of cereal samples. As a model sugar natural microbial polysaccharide pullulan was used to analytical method testing. In cereal products and food matrixes total neutral and reduced sugars as well as products of their acid and enzyme hydrolysis were measured. Detailed analysis of some glycoside composition was tested too. As the most usable method for both qualitative and quantitative analysis of cereal sugars HPLC/RI method was found. To detailed identification of malto-oligosacharides tandem LC/MS/MS technique using derivatization by 1-phenyl-3-methyl-5-pyrazolon was tested too.
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Importance of probiotics and prebiotics in human nutrition
ŠEVČÍKOVÁ, Tereza
This thesis deals with probiotics, prebiotics and the composition of intestinal microflora. The importance of intestinal microflora has long been underestimated. With the development of science the knowledge of its positive benefits and composition has been extended. Bacteria forming intestinal microflora are twofold. The "good" ones, which help in the fight against many diseases, and the "bad" ones that cause various diseases. Health beneficial bacteria which are also used to produce probiotic foods and supplements, are mainly of the Lactobacillus, Bifodobacterium, Enterococcus and Streptococcus genera. Probiotics and prebiotics are an important part of the new science discipline of "Functional food". Probiotics are live microorganisms which when administered in adequate amounts, provide a health benefits to the host. Its function help to maintain the balance of the gastrointestinal tract. The imbalance is associated with diarrhea, urinary tract infections, muscle pain and fatigue. Probiotics also have an impact on the immune system. When the immune system isn't working properly, allergic reactions, autoimmune disease (eg, ulcerative colitis, Crohn's disease and rheumatoid arthritis) and infections (eg, infectious diarrhea, Helicobacter pylori infection, skin infections and vaginal infections) may appear. Furthermore, probiotics and prebiotics contribute to the prevention of obesity, lower cholesterol levels, blood sugar levels, thereby helping with the fight against diabetes type 2 and they also help to prevent colon cancer. Furthermore, instituted or renewed balance of the microflora colonic, increases resistance to colonization of the colon microorganisms that cause diarrhea, reduce intolerance against the milk carbohydrate lactose in persons affected by this disorder, increase calcium absorption, synthesis of some vitamins and some probiotics produce bacteriocins, which are the proteins and peptides inhibiting pathogenic bacteria. On the contrary, prebiotics are indigestible food components, that beneficially affect the health of the host and selectively stimulate the growth and / or activity of one or a limited number of bacteria in the colon. They are very often used as a prebiotic oligosaccharides, which occur naturally in many kinds of vegetables and fruits.
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