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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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