This diploma thesis deals with Bisphenol A, especially with its impact on the aquatic ecosystem. Information about its properties, production and current use are summarized here. Its harmful impact on the environment, especially on the aquatic ecosystem and the human body is characterized. Also the methods of its degradation within the aquatic environment have been described. A summary of the options of a determination of Bisphenol A in water samples is incorporated and the method of gas chromatography with mass spectrometry (GC/TOF MS) and comprehensive two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS) is compared in the experimental part. Analytical determination precedes the isolation of the analyte from the water samples by solid phase extraction (SPE) using SupelcleanTM ENVITM - 18 and derivatization using the silylation reagent, N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA). The result of this work is the analysis of a series of real samples from wastewater treatment plants Brno Modřice and Luhačovice by a two-dimensional gas chromatography with mass spectrometry (GCxGC/TOF-MS).

The work presented is a substantial addition to the established methods of analysing the data generated by gas chromatography and low-resolution mass spectrometry. It has applications where these techniques are used on a large scale for screening complex mixtures, including urine samples for sports drug surveillance. The analysis of such data is usually automated to detect peaks in the chromatograms and to search a library of mass spectra of banned or unwanted substances. The mass spectra are usually not exactly the same as those in the library, so to avoid false negatives the search must report many doubtful matches. Nearly all the samples in this type of screening are actually negative, so the process of checking the results is tedious and time-consuming. A novel method, called scaled subtraction, takes each scan from the test sample and subtracts a mass spectrum taken from a second similar sample. The aim is that the signal from any substance common to the two samples will be eliminated. Provided that the second sample does not contain the specified substances, any which are present in the first sample can be more easily detected in the subtracted data. The spectrum being subtracted is automatically scaled to allow for compounds that are common to both samples but with different concentrations. Scaled subtraction is implemented as part of a systematic approach to preprocessing the data. This includes a new spectrum-based alignment method that is able to precisely adjust the retention times so that corresponding scans of the second sample can be chosen for the subtraction. This approach includes the selection of samples based on their chromatograms. For this, new measures of similarity or dissimilarity are defined. The thesis presents the theoretical foundation for such measures based on mass spectral similarity. A new type of difference plot can highlight significant differences. The approach has been tested, with the encouraging result that there are less than half as many false matches compared with when the library search is applied to the original data. True matches of compounds of interest are still reported by the library search of the subtracted data.

Synthetic fragrances or MUSK compounds are artificialy synthetised organic substances, used as fragrant constituents in various homecare products, such as cosmetics, detergents, air fresheners etc. The aim of diploma thesis was the quantification of some selected MUSK compounds in the influent and efluent of the water treatment plants.The method of quantification of MUSK compounds in organic matrix was also optimised during the research. Two modifications of solid phase microextraction were tested and evaluated. The analytes were identified and quantified by gas chromatography - mass spectrometry (GC/MS). The results were used to evaluate the amount of MUSK compounds in sewage waters and the ability of various water treatment plants to eliminate this kind of pollution from the water during the treatment process.

This study aims to determine the concentration of 16 Polycyclic Aromatic Hydrocarbons (PAHs) in urban soils from West Yorkshire in order to determine what the factors are controlling their distribution and abundances. Although PAHs have been reported before from soils and sediments, the majority of these studies have come from China, sometimes with contrasting results, which emphasises the need to obtain equivalent data from other areas. Therefore this work provides the first measurements of their type from the area studied. Soil samples were collected from one hundred sites across an area from Bradford to Leeds on two occasions, one in autumn and one in the following summer. The soil samples were analyzed by X-ray diffraction and all found to have similar mineralogical composition, which was mainly silica and calcite. Trials using iodine as a marker for PAHs showed there were notable interactions between the minerals and PAHs, with calcium carbonate absorbing PAHs much more than silica. There is a negative correlation between the soil organic content (determined by loss on ignition) and PAHs, which confirms the PAH-mineral interaction. Gas chromatography with mass spectrometry (GC-MS) using targeted selected ion monitoring was used to determine and quantify PAHs in the one hundred soil samples with the aid of PAH external standards. The results showed highest concentrations of total PAHs in the same sample from Leeds from the autumn (1,525 ng/g) and in the summer (1,768 ng/g). In Bradford there was only moderate pollution of PAHs, the maximum being 122 ng/g. However the majority of data from Bradford showed lower levels of pollution in both summer and autumn. On the basis of prior published information, the ratio of these compounds has been used to help in identifying sources. In the samples collected from Bradford in both seasons and Leeds in autumn the PAH pollution originated from pyrogenic, biomass and petroleum combustion, however in the summer the source appeared more to be from a petrogenic source. These ratios in the samples which were collected from the area between Bradford and Leeds implied pyrogenic, biomass source of pollution in the autumn, but in the summer another source of organic compounds was indicated namely petroleum combustion. When the locations were resampled nine months later, after taking into account within-site variability, there was a strong indication that the PAH concentrations were higher. This might have been due to a seasonal effect, but when a further (third) subsample was taken at a later date it showed a further increase in PAH level which suggests the effect is accumulative rather than seasonal. The results were analysed using Principal Component Analysis (PCA) to determine whether the type of road had an effect on the concentration of the 16 PAHs compounds, but it was concluded that there was no such effect. However, the distance from the soil sample to the nearest road did have an effect on the concentration of the 16 PAH compounds, especially in soil samples having the shortest distance to the road. Traffic volume was also tested and found to influence the PAH concentrations. It is notable that, comparing the groupings from autumn with those from summer by cluster analyses, they largely had the same compounds grouping together in both cases; only two compounds differed at all in where they occurred in the clusters, with consistent patterns of grouping found for the other compounds. These analyses indicate that PAH compounds behave in a consistent way amongst groups of PAH compounds. The grouping of PAHs appears linked to their sources rather than number of rings or molecular weight. / Libyan Government and Embassy

O objetivo desta pesquisa foi investigar a influência de diferentes porta-enxertos (Limão Cravo, Citrumelo Swingle, Trifoliata e Trifoliata Flying Dragon) na composição química dos óleos essenciais e dos voláteis do suco integral de tangerinas Fremont IAC 543. Os óleos essenciais da casca dos frutos foram obtidos por hidrodestilação, e variaram de 0,36 a 0,47% (v/m), sendo que a tangerina cultivada em porta-enxerto Trifoliata Flying Dragon foi a que apresentou menor rendimento de óleo essencial. A caracterização química dos óleos essenciais foi realizada por cromatografia gasosa acoplada a espectrometria de massas (GC-MS) e a semi-quantificação dos componentes dos óleos essenciais foi realizada por cromatografia gasosa acoplada a detector de ionização em chama (GC-FID). Os compostos majoritários dos óleos essenciais das variedades estudadas foram limoneno, linalol e mirceno, os quais são responsáveis por mais de 95% da área relativa dos componentes dos óleos essenciais. Devido à maior produtividade do porta-enxerto Citrumelo Swingle (18 L/ha), este é o mais indicado para produção de óleo essencial de tangerina Fremont IAC 543. Para a caracterização dos voláteis presentes no suco integral da tangerina Fremont IAC 543 foi realizada a otimização multivaridada da extração dos voláteis do suco por microextração em fase sólida de headspace (HS-SPME). Encontrou-se que a melhor condição para a extração dos voláteis consistiu no uso de fibra de divinilbenzeno/polidimetilsiloxano (DVB/PDMS), temperatura de extração de 43 °C e tempo de 31 min. Os principais compostos voláteis dos sucos integrais estudados foram o limoneno, mirceno, linalol, decanal, α-pineno, havendo bastante variação na composição dos voláteis dos sucos integrais de acordo com o porta-enxerto utilizado. Os espectros de Ressonância Magnética Nuclear mostraram que os sucos das quatro amostras analisadas possuem perfis complexos, porém semelhantes. A tangerina cultivada com porta-enxerto de Limão Cravo apresentou maiores valores de ácido málico e tirosina. A tangerina enxertada com Citrumelo Swingle apresentou maiores quantidades de ácido cítrico e etanol. A variedade plantada sobre o porta-enxerto de Trifoliata apresentou maiores valores de alanina, glicose e sacarose. A amostra cultivada sobre o porta-enxerto de Trifoliara Flying Dragon apresentou menor quantidade de etanol. Através da análise de componentes principais foi possível diferenciar as amostras a partir de seus componentes de óleo essencial e compostos voláteis e não-voláteis do suco integral de cada variedade plantada em diferentes porta-enxertos. / The objective of this research was to investigate the influence of different rootstocks (Clove Lemon, Citrumelo Swingle, Trifoliata and Trifoliata Flying Dragon) on the chemical composition of the essential oils and volatiles of the Fremont IAC 543 mandarin. The essential oils from the fruit peels were obtained by hydrodistillation, and ranged from 0.36 to 0.47% (v/w) and the mandarin cultivated in Trifoliata Flying Dragon rootstock showed the lowest essential oil yield. The chemical characterization of the essential oils was performed by gas chromatography coupled to mass spectrometry (GC-MS) and the semi-quantification of essential oil components was performed by gas chromatography coupled to a flame ionization detector (GC-FID). The major essential oils compounds were limonene, linalool, and myrcene, which were responsible for more than 95% of the essential oil components. Due to the higher productivity of the Citrumelo Swingle rootstock (18 L/ha), this was the most suitable rootstock for the Fremont IAC 543 mandarin essential oil production. Aiming the characterization of the Fremont IAC 543 mandarin juice volatiles compounds, a multivariate optimization of juice volatiles extraction by headspace solid phase microextraction (HS-SPME) was performed. It was found that the best volatile extraction conditions were the use of divinylbenzene/polydimethylsiloxane (DVB/PDMS) fiber, 43 ° C for extraction temperature and 31 min for extraction time. The main volatile compounds of the whole juices studied were limonene, myrcene, linalool, decanal and α-pinene. It possible see a considerable variation in the volatile composition of whole juices according to the rootstock used. Nuclear Magnetic Resonance spectras showed that the juices of the four samples analyzed had complex but similar profiles. Tangerine cultivated with Lemon Cravo rootstock showed higher values of malic acid and tyrosine. Tangerine growth in Citrumelo Swingle showed higher amounts of citric acid and ethanol. The variety planted on the rootstock of Trifoliata showed higher values of alanine, glucose and sucrose. The sample cultivated on the Trifoliara Flying Dragon rootstock showed less ethanol. Through the principal component analysis, it was possible to differentiate the samples using their essential oil components and volatile and non-volatile compounds from the integral juice of each variety planted in different rootstocks.

This diploma thesis deals with actual issues of the contamination in the environment with synthetic fragrances. Musk compounds are infiltrated to many environmental components (especially an aquatic ecosystem) because of their biological persistence and the ability of accumulation. This diploma thesis is focused on the selection and the optimization of method for the determination of musk compounds in real biotic matrices (fish). The isolation of analytes was realized by PSE method and the purification of extract was realized by the method of the adsorption column chromatography. Identification and quantification of individual musk compounds was carried out by GC-MS. In conclusion were results and the contamination of fish from the river Svratka disscissed and evaluated. These fish were caught at the inflow and at the outflow of the wastewater treatment plant.

Ceratitis fasciventris, Ceratitis anonae and Ceratitis rosa are polyphagous agricultural pests originating from African continent. Their behaviour is heavily altered by pheromones. Insect chemical communication channels are species-specific, represents taxonomic and reproduction barriers. Taxonomy of this group (so-called Ceratitis FAR complex) is unclear. Therefore new chemical approaches along with genetic tests for identification of entities within the cryptic species FAR complex are being developed. To study multi-component mixtures of male volatiles originating from the three mentioned fruit fly species, comprehensive two-dimensional gas chromatography with time- of-flight mass spectrometer (GC×GC-TOFMS) was used. A number of compounds were identified, out of which 23 were found to be distributed and shared among the studied species, 11 out of these were present in all three species. Analyses of male pheromone volatiles, using gas chromatography combined with electroantennographic detector (GC-EAD) revealed 4 common compounds with antennal activity shared among three studied species: methyl (E)-hex-3-enoate, 6-methylhept-5-en-2- one, linalool, and methyl (2E,6E)-farnesoate. The species-specific EAD active compounds in C. fasciventris were esters of isomers of hexenoic acid, whereas isomers of...

A dissertation submitted to the Faculty of Health Sciences, University of the Witwatersrand, in fulfilment of the requirements for the degree of Doctorate of Philosophy. / Senecio serratuloides is widely used for wound healing in South Africa but minimal information regarding its efficacy is available. Furthermore toxic pyrrolizidine alkaloids may be present. The following investigation sought firstly to evaluate the efficacy and safety of Senecio serratuloides in a porcine wound model; secondly to assess for a potential mechanism and finally isolate and identify fractions in in-vitro assays. Assessment of Efficacy and Safety Materials and Methods: Deep partial thickness and full thickness wounds were created on 9 pigs. Treatment included an occlusive dressing (negative control), activated carbon, or the Senecio preparation. Wounds were monitored using photographic documentation, pH measurement and histological analysis (skin thickness and collagen content). Toxicity was monitored on blood and liver samples. Results and Discussion: Efficacy of Senecio serratuloides was established with a significantly thicker epidermis, maximal at day 7 post-operative, 2 days before the controls. Effects on collagen content was negligible with no toxicity detected. Mechanistic investigation Materials and Methods: Wound fluid was analysed for IL-10, IL-12, IL-1β, IL-6, IL-8, TNF-α using flow cytometry based assays. Tyrosine phosphorylation and cellular proliferation was assessed using dual immunofluorescence staining. Results and Discussion: IL-1β levels were significantly greater in the Senecio treatment. Tyrosine phosphorylation increased to day 9 post-operative where it stabilised in all groups. In the same period, cellular proliferation was sustained in the Senecio treated wounds but not in the controls. Keratinocyte proliferation was identified as the target for in-vitro assays. Extraction, Isolation and Partial Identification using In-vitro Proliferation Assays. Materials and Methods: The plant was fractionated using solid phase extraction cartridges. Keratinocytes were grown under standard conditions in 96-well plates. Cellular proliferation was assessed spectrophotometrically using a resazurin dye technique. Active fractions were analysed using gas chromatography and mass spectrometry. Results and Discussion: Identified fractions increased the rate of proliferation by 300- 400%. Potential lead compounds were identified. Importantly, pyrrolizidine alkaloids could not be detected. Conclusion Senecio serratuloides is efficacious in treating deep partial thickness wounds without inducing liver toxicity. Sustained keratinocyte proliferation linked to tyrosine phosphorylation may be an underlying mechanism. Although successful, in-vitro detection of active fractions requires further characterisation.