This diploma thesis deals with the monitoring of chemical changes in ground coffee stored in various containers and then it deals with the determination of water, moisture and aromatic profile of coffee in individual containers, namely a can, a paper bag, a bag with a polyethylene liner, a bag from low density polyethylene with aluminium liner (LDPE + Al) and a glass container. At the beginning of the experiment it was found that the water content in the coffee was 4.72 ± 0.10 % and the moisture content was 9.47 ± 0.01 %. After the original sample was measured, the coffee was poured into 5 packages. At the end of the experiment, a can was chosen as the most suitable package where the lowest water content was measured. The water content was determined to be 6.51 ± 0.11 % and the moisture content was 9.93 ± 0.01 %. However, the differences between the other packages, apart from the paper bag, were very small, and thus in general it can be said that the can, the LDPE + Al package, the bag with the PE liner and the glass container are suitable for storing ground coffee. A total of 44 aromatics were identified when determining the aromatic profile in coffee by HS-SPME-GC-MS. The most represented groups of substances were furans and pyrazines. During storage, there was some loss of substances due to 2 mechanisms. The first of them is evaporation and the second one is the oxidation reactions themselves. Most aromatic substances have evaporated / degraded in paper packaging, where this large decrease is related to its barrier properties. A glass container was chosen as the most suitable packaging with the least loss of aromatic substances.

Diploma thesis is focused on cocoa beans volatile compounds from various region (Tanzania, Haiti, Ecuador, Madagascar and Peru) and chocolate bars made of them. The main aim was to judge diferences between samples according to geographycal origin. At the same time, samples of chocolates with different content of cocoa solids (50%, 70% „organic“, 70%, 78%, 90%) and a sample of cocoa powder from the common market were analyzed. Volatiles were identified and semiquantified by HS-SPME-GC-MS. A total of 86 volatile substances were identified, they were divided into 7 groups according to the nature of the odor: fruit tones (17), nut and chocolate (16), astringent and sour (12), unspecified (14), sweet nad honey (10), earthy (9) and floral (8). The data were transformed into a 2D graph by analyzing the main component according to selected distinguishing varibles. The difference in the volatile substances of cocoa beans depending on the geographical origin were confirmed using principal component analysis.

Looking at the metabolite profile of an organism provides insights into the metabolomic state of a cell and hence also into pathways employed. Little is known about the metabolites produced by corals and their algal symbionts. In particular, corals from the central Red Sea are understudied, but interesting study objects, as they live in one of the warmest and most saline environments and can provide clues as to the adjustment of corals to environmental change. In this study, we applied gas chromatography – mass spectrometry (GC–MS) metabolite profiling to analyze the metabolic profile of four coral species and their associated symbionts: Fungia granulosa, Acropora hemprichii, Porites lutea, and Pocillopora verrucosa. We identified and quantified 102 compounds among primary and secondary metabolites across all samples. F. granulosa and its symbiont showed a total of 59 metabolites which were similar to the 51 displayed by P. verrucosa. P. lutea and A. hemprichii both harbored 40 compounds in conjunction with their respective isolated algae. Comparing across species, 28 metabolites were exclusively present in algae, while 38 were exclusive to corals. A principal component and cluster analyses revealed that metabolite profiles clustered between corals and algae, but each species harbored a distinct catalog of metabolites. The major classes of compounds were carbohydrates and amino acids. Taken together, this study provides a first description of metabolites of Red Sea corals and their associated symbionts. As expected, the metabolites of coral hosts differ from their algal symbionts, but each host and algal species harbor a unique set of metabolites. This corroborates that host-symbiont species pairs display a fine-tuned complementary metabolism that provide insights into the specific nature of the symbiosis. Our analysis also revealed aquatic pollutants, which suggests that metabolite profiling might be used for monitoring pollution levels and assessing environmental impact.

Lipidy v půdě vykazují poměrně vysokou resistenci k biodegradaci, mohou proto tak zajistit informace o zdrojích organické hmoty a diagenetických procesech. Půdní organická hmota je vysoce heterogenní a vyskytují se v ní různé dynamické systémy. Vztahy mezi těmito systémy a molekulární strukturou ještě nejsou úplně známy. Analýza lipidů a bitumenu byla provedena u dvou vzroků (rašelina a lignit). Množství skupin sloučenin (volné uhlovodíky a volné ketony, vázané alkoholy, vázané mastné kyseliny, vázané -hydroxy kyseliny, volné dikyseliny a polycyklické sloučeniny) bylo idetifikováno pro oba vzorky a jejich distribuce byly určeny. GC/MS analýza volných a vázaných lipidů zjistila jejich různé zdroje během chemické degradace. Některé podobné znaky mohou být znakem uchovávání části vosků a suberinu z vyšších rostlin (dlouhé řetězce vázaných mastných kyselin). Velké rozdíly v molekulárním složení lipidů byly pozorovány mezi vzorky, dokládající význam studia lipidů z mladého sedimentu (rašelina) a starého (lignit).

Acrylamide is a carcinogenic substance generated in heat processed food stuff, where the temperature increases over 120 °C. The main acrylamide precursors are carbonyl compounds and the amino acid asparagine. In this diploma work, possible elimination strategies were observed in a bread matrix with an addition of inorganic salts into the basic powder formulation for home bread making. Samples were analyzed from the point of view of acrylamide content as well as their physico-chemical properties and sensory evaluation too. Results show, that the addition of inorganic salts hasn`t expected considerable elimination impact as in the case of model samples. It has been shown the importance of fermentation process, whereas was the amount of acrylamide in bread without yeast added almost 14times higher. The addition of CaCl2 in bread mixture improved the organoleptic quality of final product, as proved in sensory evaluation with simultaneus positive effect on acrylamide reduction in bread.

Synthetic musk compounds were first prepared artificially in the late 19th century. They have been used to perfume cosmetics, detergents and personal care products. The attention of many researchers has been focused on it recently, due to its high penetration into the nature which is a logical consequence of its great use. The main goal of this thesis is to determine the effect of the ultrafiltration on the concentration reduction of substances mentioned above in the industrial waste waters produced by the cosmetic company. Analytes from the sample were extracted using solid phase microextraction (SPME) and on gas chromatography analysis with mass spectroscopy (GC / MS) has been performed. The whole method was optimized and evaluated. Determination of the average efficiency of the ultrafiltration was made based on data obtained before and after ultrafiltration. Such efficiency determines the suitability of use of this method for removal of synthetic musk compounds from waste waters.

The grape is one of the oldest cultivated plants. It can be consumed as a fruit or it can be used as a raw material for making stews, juices or the cultivated drink – wine. Generations of wine-makers have been striving to improve both the cultivating conditions of vineyards and the quality of wine. Many harmful elements, such as herbivorous pests, diseases and storms are important factors that can have a negative impact on crop quality. To regulate the effects of these factors, an integrated protection system is used, incorporating agronomical measures, resistant varieties and a wide spectrum of pesticides. However, increasing the usage of pesticides brings certain dangers to both the production quality and the environment. This necessitates the monitoring of the negative effects, including the content of pesticide residues in the grapes. My thesis studies and experimentally assesses selected pesticide residues in certain wine samples.

The synthetic aromatic substances are present in the products of personal hygiene, detergents and cosmetics. After the application these compounds are drained away into the waste water. But the technological process used in sewage works is not able to eliminate these substances and these ones influence the particular items of the environment. The aim of the degree work is the determination of four selected items of the linear musk compounds (2-cyclohexylethanole, Fresco Menthe, Citronellol and Isobornyl acetate) in the wastewater. The real patterns were taken on the place of affluent of the sewage discharge and on the place of the draining off in the sewage plant in VFU Brno. On the basis of measurements and subsequent evaluation on of obtaining data it was possible to express the measurement of efficiency of the elimination of the present musk compounds. Firstly it was necessary to adapt the selected analytical method to the physical and chemical qualities of the prescribed analytes. The analytes were extracted from the patterns by the method of the micro extraction for the consistent phase so called solid phase microextraction (SPME). The gas chromatography in the tandem connection with the mass spectrometry makes the identification and quantification possible.

The thesis deals with monitoring of the yeast's impact to the chemical and sensorial characteristics of produced wine. The aim of experimental part was obtaining of the aroma-active substances in the fermenting must and wine Hibernal and wine Pinot Blanc. SPME-GC-MS methods were used for identify wines and must aroma. The same autochthonous yeasts were used for wine production. This yeast was isolated from surface of grapes in our laboratory. It was found that both wines have a similar aromatic profile. The next aim was the monitoring of chemical parameters of samples and their changes. For this measurement were used spectrophotometric methods and HPLC methods. The last goal of the thesis was the isolation and identification of yeasts from wine Pinot Blanc by PCR-RFLP. These yeasts were then compared with yeasts isolated from Hibernal must. Identification of yeasts were done by amplification 5,8S-ITS DNA stretches using primers ITS1 and ITS4. Restriction endonuclease HaeIII, HinfI, HhaI and TaqI. were used for restriction analysis then.

Diploma thesis is focused on study of compounds of terpenic nature in mint plants. Terpenic compounds are volatile hydrocarbons formed by several isoprenoid units with low molecular weight which cause the typical smell of plants. Presence of these compounds cause that plants seem to be fungicidal, bactericidal and insecticidal. Due to these properties, they can be used as botanical pesticides which are not toxic and no resistant organisms occur. Each plant contains relatively low concentrations of these compounds and therefore elicitors must be used for the increasing of terpenes amount. Elicitors activate defensive mechanisms in the plant leading to higher defense abilities and production of secondary metabolites. The identification and quantification of analytes was determined by gas chromatography in connection with mass spectrometry.