The thesis occupies with the use of hemp in cosmetics and in food processing. In the theoretical part hemp was characterized by the content of active substances. In the experimental part the thesis is concerned with characterization of two different hemp varieties Carmagnola and Ferimon in terms of presence of active substances. The next part focuses on preparation of cosmetic with hemp content. In cosmetic preparations and in the extracts the inhibitory effect against Propionibacterium acnes, Micrococcus luteus, Escherichia coli and Candida glabrata was tested. The content of fatty acids and vitamin E was determined in hemp seed. The results show that dried hemp flower extract contains the largest amount of active substances and has the greatest inhibitory effect against all tested bacteria except Candida there was no effect. Cosmetic preparations did not show almost any inhibitory effect because of low concentration of active substances. The hemp seed contained high amount of PUFA and essential fatty acids. Vitamin E was found out in all of three hemp oils.

This master’s thesis focuses on biodegradation of polyhydroxybutyrate (PHB) and polylactic acid (PLA). The theoretical part discusses an origin, properties and applications of investigated biopolyesters, and so the enzymology of their biodegradation. The experimental part deals with biodegradation of these polymers in liquid medium using several pure thermophilic bacteial strains and controlled composting of these bioplastics. Amongst six tested thermophilic bacterial strains only one showed PHB-biodegradation activity – strain Schlegelella thermodepolymerans. No degradation degree of amorphous or semi-crystalline PLA was observed. Mainly disintegration of both forms of PLA articles was observed in compost environment, thus the abiotic mechanism of its decomposition was indicated. After 4 weeks of composting, the relative weight loss of 99 % and 63 % was detected in amorphous and semi-crystalline PLA respectively. On the contrary, the weight loss of PHB after 4 weeks of composting reached 36 %, moreover, a half decrease of molar mass was observed using SEC. The surface erosive mechanism of PHB-biodegradation was stated using SEM. By monitoring of esterase, lipase and protease activities, no influence on the compost by polymer presence was concluded at statistical significance.

The diploma thesis is focused on the characterisation and isolation of naturally occurred active compounds, especially on lipophilic compounds. The next part of the thesis deals with enzymes and their encapsulation into alginate particles to suggest new enzymatic dietary supplement for children with optimal nutrient composition. The theoretical part is focused on the issue of child nutrition, accordingly the necessary nutrients that children need to grow without any health difficulties. It is also focused on the availability of enzymatic food supplements for children. Finally, the theoretical part deals with the lack of chosen natural substances and their effects in connection with cancer. In the experimental part, four types of oils obtained from seeds were characterized. The oils were obtained by two methods: cold pressing with a Yoda kitchen press and extraction in an organic solvent with Soxtherm. Seeds were linseed, sesame, pumpkin, and cumin. With these oils were characterized natural active substances, polyphenols, flavonoids, antioxidants, carotenoids, chlorophylls, and fatty acids. Liposomes were also prepared from selected extracts, in which an effect on intestinal tumour cells were observed. Furthermore, some enzymes were selected, and they were encapsulated into alginate particles with average size 450 µm. In these particles was specified encapsulation efficiency as well as the proteolytic activity after testing in digest juices. The last part of this thesis was focused on the optimization of a complete enzymatic food supplement with addition of alginate particles as enzyme carriers. Samples of these supplements were finally subjected to a sensory analysis.

The main topic of this diploma thesis is the study of diffusion of humic gels with incorporation of copper ions. Humic gel was prepared by precipitation of humate sodium with 5 M copper dichloride. First, it was necessary to find a useful extraction of surfactant that would have extracted copper from humic gel. Magnesium chloride was chosen as optimal surfactant from obtain relation of concentration copper(II) ions on time. Magnesium chloride was used to elution of copper from the slices of the gel. In next part it was important to verify the diffusion method that reaction in gel was not proceed in. Elution from slices of the gel before and after diffusion were scaled on the UV/VIS spectrophotometer. Experiment was prepared for times 3, 12, 24, 48 and 72 hours. Coefficient of the diffusion was calculated from obtained results, but 72 hours was not counted to the result.¨ From the coeficient of diffusion theoretic concentration profiles were calculated and then they were compared with experimentally results. Profile for 72 hours shows that it was unusable because it was oblate and fringe and concentration was lower than in other profiles. Other theoretic profiles agree.

Diploma thesis is based on diffusion processes of copper (II) ions to humic gels obtained from lignite. Solutions with various concentrations and acidity were exposed to diffusion for exact time 24 hours. After the diffusion was ended the copper (II) ionic concentration profiles of tubular gels were create and calculated total diffusion flux. The experiment showed that the higher acidity of copper (II) solution decrease an amount of immobilized Cu2+ ions to the humic gels. In comparison concentration/pH: concentration of the solution has higher influence on sorption metal ions than change of the pH.

The aim of the diploma thesis was the identification of fatty acids contained in vegetable oils by gas chromatography. Amount of fatty acids was monitored in dependence on the duration and conditions of storage. Conditions for storage were selected at room temperature and refrigerator temperature. In total fourteen oils were analyzed - avocado oil, pumpkin seed oil, grape seed oil, jojoba oil, corn oil, linseed oil, macadamia oil, almond oil, apricot-stone oil, olive oil, castor oil, rice oil, sunflower oil and soya bean oil. Gas chromatography was applied for identification and quantification of fatty acids. Methanol esterification method using potassium hydroxide catalysis was chosen for preparing of the samples of the fatty acid methylesters. Eight fatty acids were observed in the vegetable oils : myristic, palmitic, palmitoleic, stearic, oleic, linoleic, gama-linolenic and linolenic acids.

There are many changes in fruit quality during its ripening and storage. The following four apple varieties were studied: Champion, Glostr, Golden Delicious and Idaret. Amount of reducing sugars, total amount of sugars, quantities of acids, refractive solids and loss of starch were monitored. The changes of parameters, the differences between the varieties and differences in storage were compared. Parameters were monitored from mid-August 2008, when the apples ripened. After the harvest, apples were stored in a cool box at 2 - 3 ° C and at room temperature 20 - 23 ° C. Apples stored in the cool box were analyzed till the end of March 2009, and apples stored at room temperature until the beginning of January 2009. Total quantity of sugars in all varieties increases before harvest, while it decreases after picking the apples. The quantity of reducing sugars in apples rises gradually and after their picking it falls significantly in apples stored at 20 - 23 ° C. In apples stored in the cool box it continues rising until the end of November, and then it also decreases. Losses of starch are considerable and they are accelerated after the harvest. The quantity of acids also decreases throughout and amounts of refractive solids increases. For all varieties there are significant changes in storage at 20 - 23 ° C. Temperature, therefore, significantly affects processing of sugars and acids in fruit respiration.

Diploma work comparing some bakery margarins by chemical and sensoric analysis.

Předložená diplomová práce se zabývá přípravou biodegradabilního termosenzitivního triblokového kopolymeru na bázi polyethylenglykolu, kyseliny polymléčné a polyglykolové (PLGA-PEG-PLGA) a dále pak především jeho modifikací anhydridem kyseliny itakonové (ITA), který dodá kopolymeru jak reaktivní dvojné vazby tak i funkční karboxylové skupiny důležité pro reakci s biologicky aktivními látkami. Hlavním cílem bylo optimalizovat reakční podmínky pro dosažení nejvyššího stupně navázání ITA na polymer za vzniku ITA/PLGA-PEG-PLGA/ITA. Uvedený kopolymer je po vytvoření heterogenního kompozitu např. s hydroxyapatitem vhodný pro biomedicíncké aplikace především v oblasti tkáňového inženýrství jako dočasná náhrada či fixace tvrdých tkání (kostí). V teoretické části uvedené práce jsou na základě literární rešerše obecně popsány hydrogely, jejich rozdělení, síťování a degradace. Stručně jsou rozepsány fyzikální a chemické vlastnosti a syntéza jednotlivých biomateriálů použitých při syntéze, anhydridu kyseliny itakonové a jejich kopolymerů. Experimentální část popisuje detailně syntézu PLGA-PEG-PLGA kopolymeru polymerací za otevření kruhu pomocí vakuové linky a Schlenkových technik. Byla sledována i kinetika polymerace s navržením nejvhodnějších podmínek syntézy. Uvedený kopolymer byl následně modifikován anhydridem kyseliny itakonové opět katalytickou reakcí za otevření kruhu. V důsledku optimalizace reakčních podmínek byl sledován vliv teploty, rozpouštědla, času a čistoty vstupních látek. Výsledný ITA/PLGA-PEG-PLGA/ITA kopolymer byl charakterizován pomocí 1H NMR, FT-IR a GPC metody. Byly sledovány kinetiky polymerace PLGA-PEG-PLGA kopolymeru a to z přesublimované a nepřesublimované kyseliny polymléčné a polyglykolové. V obou případech probíhala kinetika reakcí bez přítomnosti rozpouštědla při 130 °C po dobu 3 hodin s konverzí asi 90 %. Delší čas neměl vliv na růst konverze. U kinetiky z nepřesublimovaných monomerů byl sledován během několika prvních minut prudký nárůst konverze a pak již byl průběh konstantní, na čase nezávislý. Výsledná polydisperzita kopolymeru byla 1,26 a molekulová hmotnost 7155 g/mol. Optimálních podmínek bylo dosaženo u polymerace z přesublimovaných monomerů, kdy byl nárůst konverze do hodnoty 88 % získané během 2,5 hodin téměř lineární (polymerace byla živá) a poté byl progres konstantní. Byl získán přesně definovaný PLGA-PEG-PLGA kopolymer o molekulové hmotnosti 7198 g/mol a polydisperzitě 1,20. Nejlepších podmínek při syntéze ITA/PLGA-PEG-PLGA/ITA kopolymeru bylo dosaženo reakcí bez přítomnosti rozpouštědla při 110 °C po dobu 1,5 hodiny s přesublimovaným anhydridem kyseliny itakonové, kdy bylo na původní kopolymer navázáno 76.6 mol. %. Výsledná molekulová hmotnost kopolymeru (5881 g/mol) s polydisperzitou 1,37 stanovená pomocí GPC se shodovala s vypočítanou molekulovou hmotností z 1H NMR i s teoretickou molární hmotností (Mn(teor)/Mn(GPC)/Mn(NMR) = 1/0,89/0,96).

Tato diplomová práce je zaměřena na porovnání termo-oxidační a chemické stability kovových komplexů huminových kyselin. Pro tyto experimenty byly vybrány tři prvky reprezentující skupinu těžkých kovů (kobalt, měď a nikl). Použitá huminová kyselina byla extrahována z Jihomoravského lignitu. Pro přípravu komplexů byly využito různě koncentrovaných roztoků kovů, aby bylo možné pozorovat vliv jejich počáteční koncentrace na obě studované stability připravených komplexů. Chemická stabilita kovových komplexů byla posuzována z hlediska uvolňování kovových iontů ze struktury huminové kyseliny do dvou různých extrakčních činidel (HCl, MgCl2). Termo-oxidační chování bylo zkoumáno pomocí technik termické analýzy: diferenční kompenzační kalorimetrie (DSC) a zejména termogravimetrické analýzy (TGA). Výsledky této práce přinášejí hlubší poznatky o problematice interakce kovů s humifikovanou částí půdní organické hmoty, využitelné k osvětlení problematiky kovových polutantů v životním prostředí a prohloubení žádoucích znalostí procedur jako jsou dekontaminace půdy a remediace.