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PRODUCTION OF BETA-GLUCANS AND OTHER POLYSACCHARIDES BY YEAST AND MICROALGAE
Byrtusová, Dana ; Kráčmar, Stanislav (referee) ; Kovalčík, Adriána (referee) ; Márová, Ivana (advisor)
Beta-glukany jsou polysacharidy složeny z monomerů D-glukózy. V dnešní době se -glukany těší zvýšené pozornosti zejména kvůli imunomodulační aktivitě a využitelnosti ve farmaceutickém a potravinařském průmyslu. Saccharomyces cerevisiae je dodnes jediným kvasinkovým zdrojem požívaným v biotechnologické produkci. Avšak některé kvasinky z oddělení Basidiomycetes, které jsou schopny produkce lipidů a karotenoidů, mohou být využity rovněž jako alternativní zdroj -glukanů. Dizertační práce se zabývá možností a optimalizací produkce -glukanů a dalších mikrobiálních sacharidů u karotenogenních kvasinek a mikrořas. Testovány byli zástupci rodů Rhodotorula, Sporobolomyces, Cystofilobasidium a Dioshegia. Z nekarotenogenních kvasinek byly do screeningu zařazeny kvasinky rodu Metschnikowia, askomycetní kvasinky a z mikrořas zástupci zelených a červených řas. Experimentální část cílí rovněž na možnosti koprodukce dalších metabolitů, jako jsou lipidy, pigmenty a extracelulární polymery. První část experimentu se zabývá vlivem čtyř C/N poměrů (10:1, 40:1, 70:1 a 100:1) na produkci biomasy, -glukanů, karotenoidů a lipidů. Ze všech testovaných kmenů, S. cerevisiae CCY 21-4-102, C. infirmominiatum CCY 17-18-4, P. rhodozyma CCY 77-1-1 a R. kratochvilovae CCY 20-2-26 vykazovaly nejvyšší produkci -glukanů a byly proto vybrány k podrobnější optimalizaci, zejména osmotického stresu, teploty a zdroje dusíku v kultivačním médiu. Dodatečně, kmen R. kratochvilovae CCY 20-2-26 je schopný produkce extracelulárních glykolipidů a S. pararoseus CCY 19-9-6 extracelulárních polysacharidů. Následně bylo stanoveno množství -glukanů u dalších dvanácti kmenů S. cerevisiae a rovněž možnost produkce polysacharidů u mikrořas.
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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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Electrochemical Analysis of Carrageenans. The Effect of Acetate Concentration
Kos, S.S. ; Paleček, Emil
kappa-, iota-, and lambda-carrageenans are polysaccharides (PSs) which produce electrocatalytic chronopotentiometric peak H-ps in acetate buffer (pH 5.2) on the hanging mercury drop electrode (HMDE). Here we show that this peak (E-p1.8V) increases with the acetate concentration Using a. c. voltammetry we found that the appearance and the observed increase of peak H-PS is accompanied by a decrease of capacitive current below the background elecnolyte around1.8 V, suggesting strong adsorption of the negatively charged PS at the negatively charged HMDE. Compared to carrageenany dextran did not produce peak H-PS and did not strongly adsorb at negatively charged electrode.
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Functionalized hybrid polymer structures for biomedical applications
Rabyk, Mariia ; Štěpánek, Petr (advisor) ; Sedláková, Zdeňka (referee) ; Kotek, Jan (referee)
This doctoral thesis is dedicated to the synthesis and characterization of novel functionalized hybrid structures for biomedical purposes. Systems reported in this work can be subdivided into the two main groups: natural-based materials and synthetic amphiphilic block copolymers. Both groups were studied as perspective theranostic agents for medical applications. In the first group, natural polysaccharides glycogen and mannan were selected as starting materials for preparation of novel nanoconjugates that possess ability for multimodal detection in vivo. Because grafting of natural macromolecules with synthetic polymers generally slows down the biodegradation rate, both polysaccharides were modified in two different ways to form nanoprobes with or without poly(2-methyl-2-oxazoline)s chains. The prepared nanoconjugates were functionalized with N-hydroxysuccinimide-activated fluorescence and magnetic resonance imaging labels. The resulting materials were tested both in vitro and in vivo and were shown to be completely biocompatible, biodegradable and exhibit some extra benefits in terms of their practical usage in biomedicine. Glycogen was functionalized with allyl and propargyl groups with following freeze-drying from aqueous solutions to form nano- and microfibrous materials. The presence of both...
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Characterization of extracellular and intracellular organic matter produced by phytoplankton in relation to water treatment
Zezulová, Tereza ; Pivokonský, Martin (advisor) ; Janda, Václav (referee)
This study investigated characteristics of algal organic matter (AOM) derived from four species (cyanobacteria Microcystis aeruginosa and Merismopedia tenuissima, diatom Fragilaria crotonensis and green alga Chlamydomonas geitleri) dominating phytoplanktonic populations in the reservoirs supplying drinking water treatment plants - the water reservoirs Švihov (the Želivka water treatment plant) and Josefův Důl (the Jizerské Mountains), Czech Republic. The four mentioned microorganisms were cultivated under laboratory conditions and the algal growth was quantified by a number of cells, chrorophyll-a and optical density. Production of AOM was evaluated by dissolved organic carbon concentration measurements, by specific UV absorbance, the amount of peptide/protein and non-peptide (carbohydrate) contents, water affinity and molecular weight (MW). AOM of all considered microorganisms are formed predominantly by hydrophilic substances with low values of specific UV absorbance (< 2 L/(m.mg)). Considerable portions of both types of AOM, i.e. extracellular and cellular organic matters are represented by substances with MW < 1 kDa or with MW > 100 kDa. However, the total amount and composition of AOM significantly depend on algal species and their growth. The obtained results imply that the knowledge of AOM...
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Optimization of chemical analysis of selected components in material of historical artworks
Pekař, Martin ; Čabala, Radomír (advisor) ; Hudeček, Jiří (referee)
The simplification of the historical pieces of work samples' treatment is described in the dissertation. The recent methods have been inappropriate therefore, modification of the treatment was necessary. The dammar and copal resin, important restoration materials, were used in the experiment. HPLC-MS, HPLC-ELSD, GC-FID, GC-MS and pyrolysis GC- MS were applied. The concentration of fatty acids in the historical sculpture was determined by GC-MS, and it was compared to the content of fatty acids inside an egg. For identification of monosaccharide in the gum, GC-MS (hexamethyldisilazan, trimethylchlorsilan, and pyridine) is the suitable method. GC-MS determines the same composition of dammar resin as stated in the cited sources. The simple process for the samples' treatment was designed.
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Use of Microwave Heating in the Synthesis of Novel Polysaccharide Derivatives.
Taubner, T. ; Synytsia, A. ; Sobek, Jiří ; Kortanková, V. ; Čopíková, J.
Microwave-assisted modification of polysaccharides is a relatively new method. Microwave heating is used for improving of extraction, hydrolytic and synthetic procedures. Modification of polysaccharides with the microwave irradiation is effective, fast and economic. The aim of this study was to apply the microwave irradiation in synthesis of carboxymethylcellulose (CMC) derivatives. This polysaccharide and its methyl ester reacted with n-butylamine yielding N-butylamide. The reactions were subsequently monitored by FUR and organic elemental analysis of the products. Degree of substitution (DS) and reaction yields were calculated based on nitrogen and carbon contents. The optimal reaction conditions were found to prepare product with the highest DS. Amino-de-alkoxylation of CMC methyl ester was significantly more effective than direct microwave assisted amidation of CMC, and microwave assisted significantly improved amino-de-alkoxylation.
Fulltext: content.csg -  PDF
Plný tet: Proceedings of the ... Tauber, T._Use of microwave - PDF
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Pectin - its properties and industrial applications
Odstrčilová, Eva ; Vránová, Dana (referee) ; Omelková, Jiřina (advisor)
This thesis deals with pectins substances in food processing and pharmaceutical industry. Pectin is very using component in food processing products, mainly due to jelly and thickening ability. The thesis is dedicated plant cell wall, where is located pectin including other material component of plant cell wall. Further it is described structure of pectin, including his production and use in industry. The last part of the thesis is dedicated enzymatic degradation of plants origin materials. Pectin is very using, but its structure and biosynthesis is still not fully explored.
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The Study of Biopolymers Stability Using Light Scattering Techniques
Kratochvíl, Zdeněk ; Sedláček, Petr (referee) ; Kalina, Michal (advisor)
The stability of chosen biopolymers (or simple carbohydrates and amino acids) was in-vestigated using light scattering methods. Samples were prepared by dissolving the sub-stance in deionised water or in diluted acetic acid. Firstly, the effect of increasing concen-tration on zeta potential was observed and the optimal concentration for the next measure-ments was determined. Afterwards, the stability and the molecular weight of used sub-stances were studied during long-time storage in different time intervals. It was found out that chitosan, CMC, hyaluronate and sodium alginate were subjected to degradation whereas increase of the molecular weight and the zeta potential was observed in case of BSA. In the end, the samples were exposed to several different external effects, namely the influence of different temperatures, UV radiation and increasing ionic strength. The results showed that rather higher temperature has a significant impact on biopolymers stability. However, used biopolymers were hardly affected by UV radiation except BSA whose molecular weight increased considerably. Decrease of the zeta potential absolute values and the molecular size usually occurred with increasing ionic strength. The change of molecular weight was not detected.
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