Contrairement à l’analyse ciblée des composés volatils du vin par chromatographie en phase gazeuse couplée à la spectrométrie de masse (GC-MS), les approches par GC-MS non ciblées prennent en compte les composés connus et inconnus. Ces méthodes sont plus rapides et fournissent une représentation plus complète de la composition de l’échantillon. Bien que plusieurs approches non-ciblées aient été développées, il y a encore une forte demande d’outils automatisés pour le traitement des données, en particulier pour les données multidimensionnelles complexes telles que celles de multiples chromatogrammes GC-MS. Ce travail visait à développer deux nouvelles approches chimiométriques pour l’analyse des données GC-MS non ciblées. Ces approches prennent en considération les décalages de temps de rétention entre les échantillons et rendent inutile l’intégration des pics. Elles ont été testées avec un jeu de données GC-MS simulées et un jeu de données GC-MS réelles d’échantillons de vin. De plus, l’une des deux approches GC-MS non ciblée a été combinée à la technique d’analyse sensorielle rapide de "projective mapping". Cette méthodologie a été utilisée pour étudier l’impact de la fermentation malolactique sur des vins issus du cépage Pinotage ainsi que l’effet de l’âge de la vigne, de la turbidité du moût et de la souche de levure sur l’arôme de vins de Riesling expérimentaux. / In contrast to targeted gas chromatography mass spectrometry (GC-MS) analysis of wine volatiles, non-targeted GC-MS approaches take information of known and unknown compounds into account, are faster, inherently more comprehensive and give a more holistic representation of the sample composition. Although several non-targeted approaches have been developed, there is still a great demand for automated data processing tools, especially for complex multi-way data such as chromatographic data obtained from multichannel detectors (e.g. GC-MS chromatograms of multiple samples). This work therefore aimed at the development of data processing procedures for non-targeted GC-MS analysis of volatile wine compounds. The two developed approaches use basic matrix manipulation of segmented GC-MS chromatograms and PCA or PARAFAC multi-way modelling. The approaches take retention time shifts between samples into account and avoid peak integration. A demonstration of the new fingerprinting approaches is presented using an artificial GC-MS data set and an experimental full-scan GC-MS data set obtained for a set of experimental wines. Results of the new approaches were also compared to a references method. Furthermore, the combination of one of the developed GC-MS fingerprinting approaches with the fast sensory screening technique projective mapping was exploited as a powerful approach to simultaneously study the volatile composition and the sensory characteristics of experimental wines. This methodology was used to study the impact of different malolactic fermentation scenarios on two different Pinotage wine styles and for a full factorial investigation of the impact of grape vine age, must turbidity and yeast strain on the aroma of Riesling experimental wines.

<p>Human activities represent a significant burden on the global water cycle, with large and increasing demands placed on limited water resources by manufacturing, energy production and domestic water use. In addition to changing the quantity of available water resources, human activities lead to changes in water quality by introducing a large and often poorly-characterized array of chemical pollutants, which may negatively impact biodiversity in aquatic ecosystems, leading to impairment of valuable ecosystem functions and services. Domestic and industrial wastewaters represent a significant source of pollution to the aquatic environment due to inadequate or incomplete removal of chemicals introduced into waters by human activities. Currently, incomplete chemical characterization of treated wastewaters limits comprehensive risk assessment of this ubiquitous impact to water. In particular, a significant fraction of the organic chemical composition of treated industrial and domestic wastewaters remains uncharacterized at the molecular level. Efforts aimed at reducing the impacts of water pollution on aquatic ecosystems critically require knowledge of the composition of wastewaters to develop interventions capable of protecting our precious natural water resources.</p><p>The goal of this dissertation was to develop a robust, extensible and high-throughput framework for the comprehensive characterization of organic micropollutants in wastewaters by high-resolution accurate-mass mass spectrometry. High-resolution mass spectrometry provides the most powerful analytical technique available for assessing the occurrence and fate of organic pollutants in the water cycle. However, significant limitations in data processing, analysis and interpretation have limited this technique in achieving comprehensive characterization of organic pollutants occurring in natural and built environments. My work aimed to address these challenges by development of automated workflows for the structural characterization of organic pollutants in wastewater and wastewater impacted environments by high-resolution mass spectrometry, and to apply these methods in combination with novel data handling routines to conduct detailed fate studies of wastewater-derived organic micropollutants in the aquatic environment. </p><p>In Chapter 2, chemoinformatic tools were implemented along with novel non-targeted mass spectrometric analytical methods to characterize, map, and explore an environmentally-relevant “chemical space” in municipal wastewater. This was accomplished by characterizing the molecular composition of known wastewater-derived organic pollutants and substances that are prioritized as potential wastewater contaminants, using these databases to evaluate the pollutant-likeness of structures postulated for unknown organic compounds that I detected in wastewater extracts using high-resolution mass spectrometry approaches. Results showed that application of multiple computational mass spectrometric tools to structural elucidation of unknown organic pollutants arising in wastewaters improved the efficiency and veracity of screening approaches based on high-resolution mass spectrometry. Furthermore, structural similarity searching was essential for prioritizing substances sharing structural features with known organic pollutants or industrial and consumer chemicals that could enter the environment through use or disposal.</p><p>I then applied this comprehensive methodological and computational non-targeted analysis workflow to micropollutant fate analysis in domestic wastewaters (Chapter 3), surface waters impacted by water reuse activities (Chapter 4) and effluents of wastewater treatment facilities receiving wastewater from oil and gas extraction activities (Chapter 5). In Chapter 3, I showed that application of chemometric tools aided in the prioritization of non-targeted compounds arising at various stages of conventional wastewater treatment by partitioning high dimensional data into rational chemical categories based on knowledge of organic chemical fate processes, resulting in the classification of organic micropollutants based on their occurrence and/or removal during treatment. Similarly, in Chapter 4, high-resolution sampling and broad-spectrum targeted and non-targeted chemical analysis were applied to assess the occurrence and fate of organic micropollutants in a water reuse application, wherein reclaimed wastewater was applied for irrigation of turf grass. Results showed that organic micropollutant composition of surface waters receiving runoff from wastewater irrigated areas appeared to be minimally impacted by wastewater-derived organic micropollutants. Finally, Chapter 5 presents results of the comprehensive organic chemical composition of oil and gas wastewaters treated for surface water discharge. Concurrent analysis of effluent samples by complementary, broad-spectrum analytical techniques, revealed that low-levels of hydrophobic organic contaminants, but elevated concentrations of polymeric surfactants, which may effect the fate and analysis of contaminants of concern in oil and gas wastewaters. </p><p>Taken together, my work represents significant progress in the characterization of polar organic chemical pollutants associated with wastewater-impacted environments by high-resolution mass spectrometry. Application of these comprehensive methods to examine micropollutant fate processes in wastewater treatment systems, water reuse environments, and water applications in oil/gas exploration yielded new insights into the factors that influence transport, transformation, and persistence of organic micropollutants in these systems across an unprecedented breadth of chemical space.</p> / Dissertation

Per- and polyfluoroalkyl substances (PFAS) have been manufactured and used in differentapplications for several decades, including food packaging materials. During the last 20 yearsthese compounds have been acknowledged as hazardous for humans and the environment, anddifferent regulations on PFAS have been established on both national and international levels.Companies started to phase-out long-chain PFAS, including both PFOA and PFOS, around 20years ago. Since PFAS are persistent, this cause concerns both for our health and theenvironment, as well as possible PFAS contamination in new products due to the recycling ofmaterials. The aim of this study was to find an effective method to extract PFAS from differentfood packaging materials; analyze the samples for their extractable organofluorine (EOF)content using combustion ion chromatography; as well as analyze targeted PFAS in the samplesusing ultra-high performance liquid chromatography tandem mass spectrometry. The findingsof this study suggest that none of the selected samples had EOF contents above the Danishindicator value of 20 mg/kg dw TOF set to determine whether PFAS has been intentionallyadded to a material, and that only two samples exceeded the limit of detection for EOF. Atakeaway bowl made out of 100% sugarcane contained the highest EOF content while the outerpackaging of a cereal box contained the second highest EOF. Both PFOA and PFOS, alongwith other long-chain PFAS were detected in a majority of the samples. The lowest total PFASconcentrations when analyzing for targeted PFAS was detected in the sugarcane take awaybowl. The highest total PFAS concentration was detected in an egg carton, followed by theouter packaging of a cereal box (same as above) and the outer box of a waffle mix. The targetedPFAS was detected in almost all samples, with PFNA and 6:2 diPAP being the most frequentlydetected PFAS. PFCAs, PFSAs, FTSAs, FOSAAs and PAPs were detected in a majority of thesamples. The highest concentrations were measured for diSAmPAP in a majority of thesamples. Mass balance calculations of the sugarcane bowl showed that the targeted PFAS onlyaccounted for 0.04% of the extractable organofluorine content. In conclusion, none of thesamples displayed EOF contents higher than the Danish indicator value, suggesting that noneof the samples were intentionally treated with PFAS. However, targeted PFAS analysis of thesesamples showed that they still contain PFAS, that could be further recycled along with therecycling of paper and board food packaging materials. Considering the persistence of PFASand that these compounds can remain in the recycling chain, with the risk of also being releasedinto the environment, it is of importance that PFAS is not introduced in any of the stages in apaper or board containers life cycle.

Durch den exzessiven Gebrauch von Antibiotika haben sich in den letzten Jahren zunehmend Resistenzen herausgebildet. Eine potentielle Alternative zu konventionellen Antibiotika sind prädatorische Bakterien. Das Bakterium Bdellovibrio bacteriovorus hat einen zweiphasigen Lebenszyklus bestehend aus einer Angriffsphase, in der es andere gram-negative Bakterien jagt, und einer Wachstumsphase, in der es das Zytoplasma eines Wirtes für die eigene Reproduktion nutzt. Für einen künftigen Einsatz von B. bacteriovorus als Antibiotikum müssen die Prozesse des Lebenszyklus verstanden werden. Das Proteom von B. bacteriovorus wurde bisher jedoch nur sehr wenig untersucht. Daher wurden in dieser Arbeit mithilfe der Massenspektrometrie Proteine von verschiedenen Zeitpunkten des Lebenszyklus von B. bacteriovorus relativ quantifiziert. Es konnten zahlreiche Proteine identifiziert werden, die zu spezifischen Zeitpunkten des Lebenszyklus hoch- oder herabreguliert werden. Die größten Unterschiede im Proteinmuster konnten zwischen der Angriffs- und der Wachstumsphase beobachtet werden. In der Angriffsphase sind einige Proteine herabreguliert, die mit der Proteinexpression im Zusammenhang stehen. Weiterhin wurde bestätigt, dass sich junge und gealterte Zellen der Angriffsphase deutlich voneinander unterscheiden, womit die Angriffsphase eigentlich aus zwei Phasen besteht. Auf Grundlage der Ergebnisse und eines Vergleiches mit Transkriptionsdaten wurde die Vermutung aufgestellt, dass B. bacteriovorus Proteine, welche spezifisch für die Angriffsphase sind, bereits während der Wachstumsphase synthetisiert. Im Zusammenhang mit der Forschung an B. bacteriovorus konnten auch neue Impulse bezüglich der MeCAT-basierten massenspektrometrischen Proteinquantifizierung angestoßen werden. In dieser Arbeit wurde unter anderem ein MeCAT-Reagenz mit Acrylamidfunktionalität entwickelt, welches erfolgreich als interner Standard für die Laserablation-ICP-MS von Polyacrylamidgelen verwendet werden kann. / Due to the excessive use of antibiotics, antibiotic resistance has increased over the last years. A potential alternative to conventional antibiotics are predatory bacteria. The predatory bacterium Bdellovibrio bacteriovorus has a biphasic life cycle consisting of an attack phase in which it hunts other gram-negative bacteria, and a growth phase in which it uses the cytoplasm of a prey cell as a substrate for its own reproduction. For future application of B. bacteriovorus as an antibiotic, it is necessary to understand the processes that occur during the life cycle. However, almost no information has been obtained regarding the proteome of B. bacteriovorus yet. Using mass spectrometry and an isotopic labelling strategy, proteins from different time points in the life cycle of B. bacteriovorus were quantified relatively to each other in this work. Numerous proteins were identified that are up- or down-regulated at specific time points in the life cycle. The largest differences in protein pattern existed between the attack phase and the growth phase, whereas only minor differences occurred within the growth phase. For instance, several proteins that appear to be down-regulated during the attack phase are related to protein expression. Furthermore, it was confirmed that there is a significant difference between young and aged cells of the attack phase. Therefore, the attack phase actually consists of two phases. Based on the results and on a comparison with transcription data, it was suggested that attack phase specific proteins of B. bacteriovorus are already synthesized during the growth phase. In connection with the research on B. bacteriovorus, new impulses regarding the MeCAT based protein quantification with mass spectrometry could be initiated. In this work, a MeCAT reagent with acrylamide functionality was developed, which can be used successfully as an internal standard for laser ablation ICP-MS of polyacrylamide gels.