L’appréciation par le consommateur d’un produit alimentaire comme le chocolat est en grande partie due à sa composante aromatique. La perception de cette composante est étroitement liée à la libération des composés d’arômes lors de la consommation du produit. Une étude sensorielle systématiquement menée par la société Valrhona dans une démarche de qualification de ses chocolats noirs de pures origines, fabriqués selon un procédé standard à partir de lots de cacao différents, permet de classer ces chocolats, selon leur profil, en quatre grands pôles sensoriels. Le travail entrepris avait pour but la compréhension de l’origine de cette classification sensorielle par la mise en œuvre de techniques de caractérisation des molécules volatiles responsables de l’arôme des chocolats.Dans un premier temps, l’empreinte globale en composés volatils d’un lot de 206 chocolats représentatifs des quatre pôles sensoriels a été obtenue via une méthode d’analyse couplant un headspace dynamique à la spectrométrie de masse en injection directe, utilisant l’ionisation par transfert de protons (PTR-ToF-MS). Des analyses multivariées des données, et notamment une analyse discriminante de type PLS-DA, ont permis d’élaborer un modèle de prédiction de la classification sensorielle des chocolats basé sur leur composition en molécules volatiles. Différentes méthodes de sélection de variables ont permis de souligner l’existence de composés volatils particuliers capables de discriminer les quatre pôles sensoriels de chocolats.Le potentiel aromatique de 12 chocolats parmi les 206 (trois de chaque pôle) a ensuite été déterminé suite à l’extraction des arômes par une méthode de distillation sous vide dans une analyse par chromatographie en phase gazeuse couplée, d’une part, à l’olfactométrie (GC-O) basée sur la fréquence de détection obtenue par 12 juges, et d’autre part, à un spectromètre de masse (GC-MS) pour l’identification des composés odorants. Ainsi, des composés d’arômes permettant de discriminer les différents pôles sensoriels ont pu être caractérisés au moyen d’une analyse factorielle des correspondances.Enfin, l’analyse « nosespace » d’un jury de 12 personnes dégustant 8 chocolats (deux de chaque pôle parmi les 12 précédents) a été réalisé en PTR-MS. Cette étude, couplée à une analyse sensorielle temporelle (Dominance Temporelle des Sensations, DTS), a permis d’obtenir des données temporelles instrumentales et sensorielles de manière simultanée. L’analyse DTS révèle dans une analyse en composantes principales (ACP) une bonne discrimination des pôles sensoriels, avec des descripteurs dominants similaires dans les pôles 1 et 4, d’une part, et dans les pôles 2 et 3, d’autre part. L’analyse nosespace a permis le suivi de la libération en temps réel de 26 composés d’arômes. La relation entre les deux jeux de données (instrumentales et sensorielles) a été étudiée au moyen de l’indice AWD (Abundance While Dominance) qui représente l’abondance de chaque ion pendant qu’une sensation est dominante. Des analyses factorielles des correspondances menées sur les AWD ont permis pour chaque échantillon de déceler des relations entre composés d’arômes libérés et sensations dominantes. / Consumers’ appreciation of chocolate is mostly due to its aromatic composition. Perception of this component is clearly linked to the release of aroma compounds during chocolate consumption. A systematic sensory evaluation is conducted by the Valrhona Company in order to qualify their pure origin dark chocolates manufactured according to a standard process from differing cocoa batches. The obtained sensory profiles allow classifying the chocolates into four sensory categories, named poles. The objective of the present work was to understand the molecular origin of this sensory classification by using techniques aimed at characterizing volatile organic compounds (VOC) responsible for chocolate flavour.Firstly, global VOC profiles of a set of 206 chocolate samples classified in the four sensory poles were analysed by a direct injection mass spectrometry method using proton transfer reaction as ionisation process (PTR-ToF-MS). A supervised multivariate data analysis based on discriminant analysis of the PLS-DA type allowed the construction of a classification model that showed excellent prediction capability based on VOC composition of the chocolates. Variable selection using dedicated methods pinpointed some volatile compounds important for the chocolates sensory discrimination.Then, the aroma potential of 12 chocolate samples (chosen among the 206 ones with three samples representative of each pole) was investigated on aroma extracts obtained by distillation under vacuum. Gas chromatography coupled to olfactometry (GC-O) and to mass spectrometry (GC-MS) was used to detect and identify the odorous compounds. GC-O data were obtained by 12 assessors using the detection frequency method. Aroma compounds allowing the discrimination of the sensory poles were determined thanks to a correspondence analysis.Finally, a nosespace analysis conducted by 12 assessors on 8 chocolates (two in each pole among the preceding 12) was realised using PTR-MS. This analysis was conducted simultaneously with a temporal sensory analysis (Temporal Dominance of Sensations, TDS), allowing temporal instrumental and sensorial data to be obtained. A principal component analysis (PCA) conducted on the TDS data revealed a good discrimination of the sensory poles, with similar dominant attributes in poles 1 and 4, on the one hand, and in poles 2 and 3, on the other hand. The nosespace data displayed real time release curves of 26 aroma compounds. The relationships between instrumental and sensory data were investigated thanks to the AWD (Abundance While Dominance) index that measures the abundance (area under the curve) of each ion during the dominance of a given sensation. Correspondence analyses of the AWD indices conducted for each chocolate sample allowed to define some relationships between dominant sensations and some released aroma compounds.

Ce projet porte sur l’étude de plusieurs plantes d’intérêt de la Lorraine afin d’extraire par voie sèche et d’analyser des substances bioactives pour une valorisation de la flore locale. Un procédé de broyage et de tamisage de matériel végétal en de fines particules est utilisé afin de concentrer les composés bioactifs dans les poudres résultantes. Les poudres présentent des tailles de particules allant de 20 µm à 500 µm. Les propriétés phytochimiques de chaque classe granulométrique sont comparées à celle des parties de plantes non tamisées. Ces activités sont liées aux métabolites secondaires notamment les polyphénols et les dérivés terpéniques, qui sont caractérisés et quantifiés par des analyses LC-MS et GC-MS. Au cours de ce travail ont été développés : - la validation d’une nouvelle technique de séparation différentielle en fonction de la granulométrie des poudres par comparaison avec des extraits de plantes non tamisées ; - le dosage des différents constituants chimiques par des méthodes spectrométriques (UV/Visible), la caractérisation par des techniques analytiques telles que la LC-MS et GC-MS ; - l’évaluation du potentiel antioxydant/anti-radicalaire et anti-acétylcholinestérase réalisée par voie chimique in vitro en fonction des classes granulométriques. Cette étude démontre l’intérêt que présente ce nouveau procédé d’extraction différentiel des composés bioactifs issue de matrices végétales. Un enrichissement en produits actifs est observé au niveau de certaines classes granulométriques. Au niveau des activités antioxydantes pour toutes les plantes et de l’activité anti-acétylcholinestérase dans le cas du saule blanc, on observe des variations significatives en fonction de la taille de particules des échantillons des poudres superfines. L’étude de l’activité anti-acétylcholinestérase a été complétée par une modélisation in silico afin de mettre en évidence l’interaction entre les composés et les sites actifs de l’enzyme acétylcholinestérase / This project focuses on the study of 12 plants coming from Lorraine region. The study aims to improve the exploitation of local flora using a dry extraction process. A milling and a sieving process up to fine particles of plant material is used to concentrate the bioactive compounds in the resulting powders. The powders were classified according to the particle size which were ranging from 20 µm to 500 µm. The phytochemical properties of each particle size fraction are compared to non-sieved plant parts. These activities are linked to secondary metabolites including polyphenols and terpene derivatives, which are characterized and quantified by LC-MS and GC-MS analyses. It was developed in this work a new validation technique of differential separation depending on the particle size of the powders compared with extracts of non-sieved plant parts. The quantification of chemical compound classes was done by UV-Visible methods and their identification was conducted using LC-PDA/MS and GC-MS characterization technics. The evaluations of the antioxidant activity and anti-acetylcholinesterase activity is carried out in vitro according to the particle sizes. This study demonstrates the usefulness of this new differential extraction process of bioactive compounds from vegetal matrices. The Enhancing of the concentration of the active products is observed according to the particle sizes. In silico modeling study of anti-acetylcholinesterase activity is employed to highlight the interactions between the active sites and some anticipated active compounds in the extract

Quatro linhagens capazes de crescer com acefato foram isoladas a partir de solos com históricos de aplicação de deste composto. Stenotrophomonas maltophilia, Rhodococcus sp., Staphylococcus sp. e Pandoreae sp. foram identificadas através do rDNA 16S e perfil de ácidos graxos de membrana. Rhodococcus sp. foi o isolado mais eficiente na degradação de acefato, removendo 99.24% deste composto em meio de cultura com acefato como única fonte de carbono. Quando avaliado com acefato como fonte combinada de carbono e nitrogênio, este organismo degradou 19% de acefato com formação de metamidofós (17%). Staphylococcus sp. apresentou 21% de degradação de acefato utilizando-o como fonte de carbono e nitrogênio, mas não manteve o crescimento com este composto como fonte de carbono. Stenotrophomonas maltophilia e Pandoreae sp. não mantiveram crescimento com acefato como única fonte de carbono isoladamente. Estas linhagens apresentaram crescimento em acefato como fonte de nitrogênio e enxofre, porém, as análises de GC/MS demonstraram que não houve degradação nestas condições. / Four strains of microorganisms capable of growth on acephate were isolated from soil samples with a history of acephate application. Stenotrophomonas maltophilia, Rhodococcus sp., Staphylococcus sp. and Pandoreae sp. were identified based on 16S rRNA gene sequencing and fatty acid profiling. Rhodococcus sp. was the most efficient acephate degrader of the isolates, it removed 99.24% of acephate from defined growth media when the compound was provided as sole carbon source. When provided as a combined carbon and nitrogen source, the organisms degraded 19% of acephate with formation of methamidophos (17%). Staphylococcus sp. degraded 21% of acephate when provided as sole nitrogen and carbon source but did not grow on the compound as a sole source of carbon. Pandoreae sp. and Stenotrophomonas maltophilia failed to grow on acephate as sole source of carbon in defined medium. These strains grew in media where the pesticide was provided as a combined nitrogen and carbon source, but no acephate biodegradation could be demonstrated in these instances.

A análise de tintas e papéis é de grande interesse para a ciência e a interação tinta-papel é importante em vários níveis. A análise da tinta de um documento é extremamente importante para o estudo de diferentes aspectos, como adulterações e determinação da recentidade. Esses aspectos podem ser estudados analisando a tinta e o papel tanto fisicamente quanto quimicamente. Portanto, o desenvolvimento de uma técnica para a análise de tintas de caneta esferográfica e a determinação da recentidade de um documento é interessante para a Ciência Forense. No Brasil, cientistas forenses enfrentam todos os dias diversos casos que requerem a análise de tintas de caneta esferográfica, e não se tem nenhuma técnica onde a determinação da idade de uma tinta é possível. Os casos mais comuns onde há a necessidade da recentidade de um documento são fraudes em recibos de pagamento e de quitação de dívidas, preenchimento e assinatura de contratos, adulteração em documentos e em cheques. Neste trabalho, é discutida uma nova metodologia para a análise de tintas de canetas esferográficas e a sua utilização na determinação da recentidade de uma amostra de tinta de caneta esferográfica. Foram analisadas periodicamente amostras provenientes de diferentes países, como Estados Unidos, Canadá, Peru, Japão, Espanha e Grécia. Com os resultados obtidos, foram construídas curvas de degradação do solvente em função do tempo de preparo. Com as curvas, obtiveram-se as equações logarítmicas relativas. As equações propostas mostraram ser capazes de distinguir a idade relativa de uma tinta, com 20% de variação em relação ao valor teórico. Portanto, a principal conclusão deste trabalho é a metodologia proposta pode ser utilizada para determinar a idade relativa de uma tinta de caneta esferográfica. / The analysis of inks and papers are of great interest to science and an understanding of the interaction between ink and paper is very important in mamy levels. The ink analysis from a document is extremely important to the study of several aspects such as adulteration and the age of the ink. These aspects could be studied by analysing the ink and paper both physically and chemically. The development of a technique to analyse ballpoint pen ink and to determine the age of a document by analysing the ink applied on a paper is very helpfull for every aspect of Forensic Science. In Brazil, Forensic Scientists face everyday many cases that require the ballpoint pen ink analysis, and there are no methods in which the determination of the ink age is possible. The most habitual cases which ink age analysis is requested are frauds in receipts, debt quittances, contract completions, signatures, adultered documents and checks. In this work, a new methodology of the ballpoint ink pen and its utilization to determine the age of a ballpoint ink sample will be discussed. Ballpoint pen ink samples from different countries such as the United States, Canada, Peru, Japan, Spain and Greece were periodically analysed. With the obtained results and according to the preparation time, curves of degradation of the solvent were built. The logarithmic equations from the curves were obtained too. The proposed equation has shown to be able to distinguish the relative age of the ballpoint ink with a variation of 20% from the theoretical value. Therefore, the main conclusion of this work is that the methodology proposed could be used to determine the relative age of a ballpoint ink pen.

A produção e emissão de poluentes é geralmente derivada da alta atividade humana, por meio da utilização dos recursos naturais, desenvolvimento de infraestrutura e construção, atividades agrícolas, desenvolvimento industrial, urbanização, turismo e uma série de outras atividades. Poluente é tudo o que é introduzido pelo homem, de forma direta ou indireta, de substâncias ou energia que resultem ou possam resultar em efeitos adversos a vida. As principais classes de poluentes são os pesticidas, poluentes orgânicos, nutrientes, óleos, isótopos radioativos, metais pesados, patogênicos, sedimentares, lixo e escombros entre outros. O descarte em efluentes aquáticos é uma prática antiga no modo como lidamos com nossos dejetos e em consequência disso, a maioria dos ambientes aquáticos encontram-se poluídos em maior ou menor grau. Dentre os poluentes orgânicos, encontramos uma classe de moléculas denominadas de hidrocarbonetos policíclicos aromáticos (HPA). Os HPAs são uma grande família de compostos derivados da fusão de anéis benzênicos que contém dois anéis benzeno fundidos e seus derivados, até estruturas contendo 10 anéis. A toxicidade dos HPAs é resultado de sua hidrofobicidade. Estes compostos podem induzir mudanças conformacionais na estrutura de biomembranas resultando em aumento em sua permeabilidade. Como consequência, a capacidade fotossintética desses organismos é prejudicada podendo levar a sérios distúrbios na cadeia de transporte de elétrons e desacoplamento da fosforilação oxidativa. O Antraceno (ANT) é uma molécula formada pela fusão de 3 anéis benzênicos e é um dos 16 HPAs prioritários segunda a US EPA, e é classificado como muito tóxico para organismos aquáticos e que pode causar efeitos adversos de longo prazo no ambiente aquático. Além disso, ANT é facilmente fotoxidado a produtos ainda mais tóxicos, especialmente quinonas, que interferem na respiração e na fotossíntese, causando problemas no desenvolvimento das algas levando a falência do ecossistema devido à diminuição da biomassa, deficiência de oxigênio e inibição de processos de desintoxicação. A quantidade de informações referentes aos efeitos causados ao metabolismos destes organismos fotossintetizantes é bastante limitada e para suprir esta carência, utilizamos a microalga modelo Chlamydomonas reinhardtii com a finalidade de ampliar o conhecimento dos efeitos tóxicos de antraceno no metabolismo destes organismos utilizando uma abordagem de metabolômica que utiliza GC-MS. Como resposta metabólica a exposição de ANT, ácidos graxos acumularam em C. reinhardtii. De forma semelhante, outra resposta encontrada foi acumulo de aminoácidos. Com exceção de valina, todos os aminoácidos encontrados em nossa análise por GC-MS se acumularam nas culturas expostas a ANT. Outra molécula importante encontrada em nossas análises foi a glutationa, possivelmente causada pela produção de EROs. Muitos ácidos carboxílicos foram encontrados em nossas análises e entre estes, a via metabólica mais impactada foi o ciclo do glioxilato. Juntamente com acumulo de glioxilato, muitos intermediários do ciclo do ácido cítrico foram encontrados tais como succinato e malato. Para tanto, o acumulo de malato é dependente de glioxilato e acetato, presente no meio de cultura. O produto deste gene catalisa a reação entre glioxilato e acetil-CoA formando malato como produto final. Com estes dados, podemos sugerir que para compensar pela fotossíntese deficiente, o metabolismo heterotrófico de acetato produzindo acetil-CoA é uma fonte importante de energia, e a via de glioxilato tem um papel central durante o estresse causado por ANT. Além disso, a incorporação de carbonos através do ciclo do glioxilato pode permitir a síntese de outras moléculas mais complexas como aminoácidos, lipídeos e carboidratos. / The production and emission of pollutant are often derived from human activities, such as utilizing natural resources, developing infrastructure, agriculture and industry among others. Pollutant is defined as substances or energy introduced into the environment by man, directly or indirectly that may result in adverse effects on life. Pollutants can be divided into various classes including organic, nutrients, oils, radioactive isotopes, heavy metals, pathogenic, sediments, garbage among others. Disposal of sewage on water bodies is an old habit of how we deal with our wastes. Consequently, great part of the aquatic environment becomes polluted in various extents. Among the organic pollutants, polycyclic aromatic hydrocarbons (PAH) represents a class of molecules consisting from two or more fused benzene rings and its by-products. Members of this class of compounds have been identified as exhibiting toxic and hazardous properties. Their toxicity is also due to its hydrophobic property that induces conformational changes on membranes, increasing their permeability. Consequently, the photosynthetic capacity of exposed organisms can be harmed, leading to serious imbalances on their electron chain transport and uncoupling oxidative phosphorylation. Anthracene (ANT) is a PAH formed by three fused benezenic rings and is one of the 16 prioritary PAH according to American and European regulatory agencies. ANT is classified as highly toxic for aquatic organisms causing long term effects on environment. Besides, ANT can be easily photooxidated and its products can be even more toxic, specially quinones, that can interfere on respiration and photosynthesis, leading to problems on algae development and ecosystem collapse caused by low biomass, oxygen deficiency and inhibition of detoxification processes. The amount of information about the effects on metabolism of the photosynthetic organisms is limited. Therefore our main goal was to use the model organism Chlamydomonas reinhardtii in order to gain insights on the toxic effects caused by ANT through GC-MS metabolomics approach. A metabolic response to ANT exposure, lipid accumulates in C. reinhardtii. Similarly to fatty acids, another marked physiological response was amino acids accumulation. With the exception of valine, all amino acids found in our GC-MS analysis showed a marked relative accumulation in cultures exposed to ANT. Another important finding was the high level of glutathione, possibly caused by ROS production. Carboxylic acids were also found in our analysis and among them a highly impacted pathway found was glyoxylate cycle. Toghether with the increase accumulation of glyoxylate, many TCA cycle intermediates, like succinate and malate were found. Furthermore, malate accumulation is dependent of glyoxylate and acetate, present in culture media. The product of this gene catalyse the reaction between glyoxylate and acetyl-CoA forming malate as a final product. Taken all together, our findings suggest that to compensate the photosynthesis inhibition, heterotrophic acetate metabolism was activated producing acetyl-CoA an important energy source, and glyoxylate cycle plays a central role during stress caused by ANT. Furthermore, incorporation of carbon through glyoxylate cycle can enable synthesis of more complex molecules like amino acids, lipids and carbohydrates.

Cloropropanóis são um grupo conhecido de contaminantes relacionados ao processamento de alimentos. Eles são formados na reação entre lipídeos e cloretos quando submetidos ao tratamento térmico, e podem ser encontrados na forma livre ou ligada. O 3-monocloro-1,2-propanediol (3-MCPD), é classificado pela IARC como possível carcinógeno humano (grupo 2B). O glicidol (e seus ésteres), é classificado também pela IARC como uma substância provavelmente carcinogênica para seres humanos (grupo 2A), e, recentemente, vem sendo encontrado em alimentos. O objetivo deste trabalho foi avaliar a presença do 3-MCPD e do glicidol em óleos vegetais comestíveis utilizando a cromatografia gasosa com detector de massa triplo quadrupolo MS/MS. A técnica utilizada foi a preconizada pela AOCS Cd 29c-13, sendo uma análise indireta, e foi possível adaptá-la visando as determinações do 3-MCPD e glicidol através da construção de curvas de calibração e análises de amostras de referência. O método foi validado e os resultados indicaram o limite de detecção do composto 3-MCPD, de 42,4 µg/kg e o limite de quantificação de 50 µg/kg, e para o Glicidol indicaram o limite de detecção de 43,5 µg/kg e limite de quantificação de 50 µg/kg. Os resultados para 3-MCPD obtidos nos ensaios da curva de calibração e linearidade demonstraram que o método foi capaz de expressar resultados com boa linearidade (0 - 10 mg/kg , r2, = 0.9991). Os resultados obtidos nos ensaios de exatidão obedeceram aos critérios de 70 a 120% de recuperação, e ±20% de variação entre os resultados de acordo com SANTE (2017). O método em questão demonstrou ser seletivo, uma vez que não foram observados picos interferentes nos tempos de retenção dos compostos estudados. Os ensaios de precisão nos níveis baixos, médio e alto e robustez demonstraram que o método é robusto e preciso, portanto a validação foi considerada adequada ao uso pretendido. Foram analisadas 368 amostras de óleos vegetais (76 amostras de óleo de canola, 48 amostras de óleo de milho, 69 amostras de óleo de algodão, 33 amostras de óleo de palma, 10 amostras de óleo de palmiste, 50 amostras de oleína de palma, 30 amostras de óleo de soja e 51 amostras de óleo de girassol). As concentrações das amostras analisadas apresentaram resultados para 3-MCPD com valores médios entre 203 a 1205 µg/kg. Para o Glicidol os valores foram de 2 a 1198 µg/kg, com elevado o desvio padrão entre os resultados analíticos, onde o óleo de palma apresentou a maior variação de 1600 a 5260 µg/kg. Através da avaliação do risco realizada para o composto 3-MCPD foi possível detectar, utilizando o critério do pior cenário de exposição e resultados analíticos, os valores diários de consumo de óleo de algodão de 0,044 µg/kg p.c., de óleo de girassol 0,045 µg/kg p.c., óleo de canola 0,18 µg/kg p.c., óleo de palma de 0,28 µg/p.c, óleo de milho de 0,0462 µg/kg p.c., e o óleo de soja, de maior consumo no Brasil (72%) apresentou o valor de 0,27 µg/kg p.c. O consumo de todos estes óleos, pela a população brasileira, pode ser considerado seguro ao comparar com o valor de TDI Ingestão Diária Tolerável - de 2µg/kg p.c.. Através da avaliação do risco realizada também utilizando o critério de pior cenário de exposição e e resultados analíticos para o composto glicidol foi possível verificar que os valores diários de consumo de óleo de algodão de 0,061 µg/kg p.c., de óleo de girassol 0,03 µg/kg p.c., óleo de canola 0,13 µg/kg p.c. e de óleo de palma de 0,57 µg/p.c, de óleo de milho de 0,11 µg/kg p.c, e o óleo de soja de maior consumo no Brasil (72%) não ultrapassam o valor de 0,288 µg/kg p.c indicando consumo seguro destes óleos para a população brasileira baseado na TDI de 1000µg/kg p.c. / Chloropropanols are a known group of contaminants related to food processing. They are formed during the reaction process between lipids and chlorides when submitted to heat treatment and can be found in free or bound form. The 3-monochloro-1,2-propanediol (3-MCPD), is classified by IARC as a possible human carcinogen (group 2B). Glycidol (and its esters), also classified by IARC as a substance likely to be carcinogenic to humans (group 2A), has recently been found in food. The present study aims to evaluate the presence of 3-MCPD and glycidol in edible vegetable oils using gas chromatography with triple quadrupole MS/MS mass detector. The technique applied is recommended by AOCS, guide Cd 29c-13, an indirect analysis, and allows quantification of 3-MCPD and glycidol by building the calibration curves and analysis of reference samples. The method was validated and the detection limit of the contaminant 3-MCPD of 42,4 µg/kg and the quantification limit of 50 µg/kg was established. For Glycidol the detection limit of was 43,5 µg/kg and quantification limit was 50 µg/kg. The results obtained in the calibration and linearity curves demonstrated that the method could express results with good linearity (0 10 mg/kg, r2, = 0.9991). The results obtained in the trueness trials agreed to the criteria of 70 to 120% of recovery, and ± 20% of variation between the results according to what is preconized by SANTE (2017). The method showed to be selective, since no interfering peaks were observed in the retention times of the studied compounds. The tests performed on low, medium and high values demonstrated the robustness and precision of the method, so the validation was considered completed and suitable for the purpose. A total of 368 vegetable oil samples were analyzed (76 samples of canola oil, 48 samples of corn oil, 69 samples of cottonseed oil, 33 samples of palm oil, 10 samples of kern palm oil, 50 samples of palm olein, 30 samples of soybean oil and 51 samples of sunflower oil). The results found in samples for 3-MCPD were within mean values between 203 and 1205 µg/kg. The results found in samples for glycidol were within mean values between 2 to 1198 µg/kg where palm oil presented the highest variation for glycidol from 1600 to 5260 µg/kg. Through the risk assessment for the contaminant 3-MCPD it was possible to detect the values based on exposed worst case scenario and analytical results. The results for cottom oil were 0,044 µg/kg bw, sunflower 0,045 µg/kg bw, canola 0,18 µg/kg bw and palm oil 0,28 µg/kg bw, corn oil 0,0462 µg/kg bw, and for soybean, which is the most consumed oil in Brazil (72%) the value of 0,27 µg/kg bw. These results indicates safe consumption for these oils based in the Theoretical Daily Ingestion - TDI of 2µg/kg bw. The risk assessment for the glycidol based on exposure worst case scenario and analytical results presented for cottom oil the value of 0,061 µg/kg bw, sunflower 0,03 µg/kg bw, canola oil 0,13 µg/kg bw , palm oil 0,57 µg/kg bw, corn oil 0,11 µg/kg bw and for soybean, which is the most consumed in Brazil - 72% the value of 0,27 µg/kg bw. These results indicates safe consumption for these oils based in the TDI of 1000µg/kg bw.

Le film hydrolipidique est « l’ultime frontière entre l’organisme et l’environnement ». Ainsi, il offre à la peau une bonne protection et contribue largement à ses propriétés. Cependant, il peut être impliqué dans plusieurs perturbations cutanées. Le but de ce travail était d’obtenir un profil global de l’ensemble des lipides cutanés de surface, riche en informations structurales et capable de décrire l’organisation de ces molécules, permettant de suivre l’évolution physiologique du film hydrolipidique au niveau moléculaire. Plusieurs approches analytiques ont été développées et des outils statistiques et chimiométriques ont été utilisés pour exploiter les résultats.La caractérisation des lipides cutanés de surface (LCS) a été réalisée en chromatographie en phase gazeuse à haute température couplée à la spectrométrie de masse (HT-GC/MS). Le protocole analytique a été développé en conservant les structures lipidiques dans leur état intact. Plus de 200 composés ont été identifiés et répartis en 5 classes : acides gras libres, hydrocarbures, cires, stérols et glycérides. L’acide palmitique (C16:0) et l’acide sapiénique (C16:16) sont prépondérants et entrent dans la structure de très nombreux composés. Plusieurs approches quantitatives ont été mises en place : calcul des descripteurs chromatographiques, normalisation interne pour l’analyse par classe et exploitation chimiométrique des composés considérés individuellement.Trois problématiques ont été explorées par ces techniques et ont conduit aux résultats suivants :La répartition des LCS sur différentes zones corporelles se traduit par un ratio squalène/cholestérol plus élevé dans les zones riches en glandes sébacées que dans les zones pauvres. Ce descripteur est ainsi un bon critère d’évaluation de la balance sécrétion sébacée/desquamation. L’évolution des LCS en fonction de la localisation géographique et/ou la couleur de la peau a été étudiée en cherchant les variations de la composition par HT-GC/MS et de l’organisation par spectroscopie Raman. Une différence de composition a été mise en évidence entre les volontaires en fonction de la localisation géographique : le composé le plus impliqué est l’acide sapiénique (C16:1Δ6). Une différence de conformation (trans/gauche) au niveau des chaînes alkyles a été détectée.Enfin, l’adaptation de la barrière cutanée après la naissance a été déjà signalée mais sa traduction au plan moléculaire a pu être étudiée par le protocole analytique développé, chez les nourrissons dès les premiers jours après la naissance jusqu’à l’âge de 6 mois. Une diminution de la quantité globale de sécrétion sébacée a été observée, avec en parallèle, une augmentation sélective du cholestérol estérifié par des acides gras d’origine épidermique. Ceci indique un accroissement de la participation relative des lipides épidermiques dans le film hydrolipidique comme résultat d’une diminution de la sécrétion sébacée.Les approches analytiques développées dans ce travail de thèse permettent une caractérisation moléculaire fine des LCS en vue d’étudier l’évolution physiologique du film hydrolipidique. Les outils statistiques et chimiométriques ont permis une exploitation plus poussée des résultats pour extraire des informations inaccessibles par les approches classiques. Ce travail d’investigation offre de nombreuses perspectives, très prometteuses dans le domaine médical et dans le domaine cosmétique. / Skin hydrolipidic film is "the final frontier between the organism and the environment." Thus, it provides skin protection and contributes to its properties. However, it may be involved in several skin disturbances. The aim of this study was to obtain an overall profile of skin surface lipids (SSLs), rich in structural information and able to describe the organization of these molecules. This information allows monitoring the physiological evolution of hydrolipidic film at the molecular level. Several analytical approaches have been developed and chemometric and statistical tools were used to improve the interpretation of the results.SSL characterization was performed using high-temperature gas chromatography coupled with mass spectrometry (HT-GC/MS). The analytical protocol has been developed keeping the lipids in their intact structures. Over than 200 compounds were identified in the same run. These compounds have been classified in five lipid classes: free fatty acids, hydrocarbons, waxes, sterols and glycerides. The palmitic acid (C16:0) and sapienic acid (C16:16) are predominant and participate in the structure of many compounds. Several quantitative approaches have been implemented: calculation of chromatographic descriptors, normalization of the peak area for analysis by class and chemometric exploitation of individual compounds data.Three issues were explored by these techniques and lead to have the following results:The SSL distribution on different areas of the body, expressed as a squalene / cholesterol ratio, is higher in body areas rich in sebaceous glands than in poor areas. This descriptor is thus a good criterion for sebum secretion / desquamation balance measurement.The SSL evolution based on the geographical location and / or color of skin has been investigated by studying the variations in the composition and organization using HT-GC/MS and Raman spectroscopy. A difference in composition has been demonstrated between the volunteers according to geographical location: the most involved compound is the sapienic acid (C16: 1Δ6). A difference in conformation (trans / gauche) of at the alkyl chains was detected. Skin barrier adaptation after birth has already been reported. In this study, its evolution at the molecular level has been studied in infants from the first days after birth until the age of 6 months. A decrease in the total amount of sebaceous secretion was observed with, in parallel, an increase of cholesterol esterified with fatty acids of epidermal origin. This indicates an increase in the relative participation of epidermal lipids in the hydrolipidic film as the result of a decrease in sebaceous secretion. The analytical approaches developed in this thesis provide a detailed molecular characterization of SSLs in order to study the physiological evolution of the skin hydrolipidic film. Statistical and chemometric tools have allowed further exploitation of the results to extract information not accessible by conventional approaches. This investigative work offers many opportunities, promising in medicine and in cosmetics.

Les accumulateurs graphite/LiNi0,5Mn1,5O4 (LNMO) permettent d’atteindre des densités d’énergie élevées grâce à leur tension de 5V. Toutefois, une dégradation des électrodes et des électrolytes à base d’alkylcarbonates et de LiPF6 a lieu à haut potentiel reste un problème qu’il est nécessaire de résoudre. L’ajout d’additifs fonctionnels à l’électrolyte comme l’AS, l’AM, le FEC ou le LiBOB forme des films de passivation aux interfaces électrode/électrolyte. Ces films réduisent la dégradation des matériaux et de l’électrolyte de l’accumulateur Gr/LNMO. Pour étudier le mécanisme d’action de ces additifs, les interfaces graphite/électrolyte et LNMO/électrolyte ont été caractérisées au moyen de cellules symétriques Gr/Gr et LNMO/LNMO et de cellules complètes. Les interfaces ont été étudié par spectroscopie d’impédance électrochimique (EIS) et photoélectronique à rayons X (XPS). De plus, l’électrolyte a été analysé par chromatographie en phase gazeuse liée à la spectrométrie de masse (GC-MS). / Gr/LiNi0.5Mn1.5O4 (LNMO) accumulators achieve higher energy densities than current commercial batteries. However, degradation of electrodes and electrolytes based on alkylcarbonates and LiPF6 takes place at high potential remains a problem which it needs to be resolved. The addition of functional additives to the electrolyte such as AS, AM, FEC or LiBOB which form passivation films at the electrode/electrolyte interfaces is a possible solution to these issues. These films reduce the degradation of materials and the oxidation of electrolyte in the Gr/LNMO accumulator. In order to study action mechanism of these additives, graphite/electrolyte and LNMO/electrolyte interfaces were characterized by symmetric Gr/Gr and LNMO/LNMO cells and full cells. Interfaces were investigated by electrochemical impedance spectroscpoy (EIS) and X-ray photoelectron spectroscopy (XPS) while the electrolyte was analyzed by mass spectrometric gas chromatography (GC-MS).

A análise de tintas e papéis é de grande interesse para a ciência e a interação tinta-papel é importante em vários níveis. A análise da tinta de um documento é extremamente importante para o estudo de diferentes aspectos, como adulterações e determinação da recentidade. Esses aspectos podem ser estudados analisando a tinta e o papel tanto fisicamente quanto quimicamente. Portanto, o desenvolvimento de uma técnica para a análise de tintas de caneta esferográfica e a determinação da recentidade de um documento é interessante para a Ciência Forense. No Brasil, cientistas forenses enfrentam todos os dias diversos casos que requerem a análise de tintas de caneta esferográfica, e não se tem nenhuma técnica onde a determinação da idade de uma tinta é possível. Os casos mais comuns onde há a necessidade da recentidade de um documento são fraudes em recibos de pagamento e de quitação de dívidas, preenchimento e assinatura de contratos, adulteração em documentos e em cheques. Neste trabalho, é discutida uma nova metodologia para a análise de tintas de canetas esferográficas e a sua utilização na determinação da recentidade de uma amostra de tinta de caneta esferográfica. Foram analisadas periodicamente amostras provenientes de diferentes países, como Estados Unidos, Canadá, Peru, Japão, Espanha e Grécia. Com os resultados obtidos, foram construídas curvas de degradação do solvente em função do tempo de preparo. Com as curvas, obtiveram-se as equações logarítmicas relativas. As equações propostas mostraram ser capazes de distinguir a idade relativa de uma tinta, com 20% de variação em relação ao valor teórico. Portanto, a principal conclusão deste trabalho é a metodologia proposta pode ser utilizada para determinar a idade relativa de uma tinta de caneta esferográfica. / The analysis of inks and papers are of great interest to science and an understanding of the interaction between ink and paper is very important in mamy levels. The ink analysis from a document is extremely important to the study of several aspects such as adulteration and the age of the ink. These aspects could be studied by analysing the ink and paper both physically and chemically. The development of a technique to analyse ballpoint pen ink and to determine the age of a document by analysing the ink applied on a paper is very helpfull for every aspect of Forensic Science. In Brazil, Forensic Scientists face everyday many cases that require the ballpoint pen ink analysis, and there are no methods in which the determination of the ink age is possible. The most habitual cases which ink age analysis is requested are frauds in receipts, debt quittances, contract completions, signatures, adultered documents and checks. In this work, a new methodology of the ballpoint ink pen and its utilization to determine the age of a ballpoint ink sample will be discussed. Ballpoint pen ink samples from different countries such as the United States, Canada, Peru, Japan, Spain and Greece were periodically analysed. With the obtained results and according to the preparation time, curves of degradation of the solvent were built. The logarithmic equations from the curves were obtained too. The proposed equation has shown to be able to distinguish the relative age of the ballpoint ink with a variation of 20% from the theoretical value. Therefore, the main conclusion of this work is that the methodology proposed could be used to determine the relative age of a ballpoint ink pen.

A subtribo Lychnophorinae ocorre na região do Cerrado do Brasil e contém cerca de 120 espécies. Recentemente, a filogenia da subtribo Lychnophorinae, baseada em sequências de DNA e dados morfológicos foi capaz de fornecer novas informações sobre a subtribo e seus gêneros. Além disso, o Cerrado brasileiro possivelmente abriga uma parcela considerável da entomofauna neotropical. Os objetivos gerais deste projeto de pesquisa são obter perfis metabólicos de plantas da subtribo Lychnophorinae e utilizá-los como ferramenta quimiotaxonômica para auxiliar na resolução da classificação taxonômica dessa subtribo e ainda, obter perfis metabólicos de insetos que se alimentem dessas plantas, visando a identificação de possíveis interações inseto-planta. Foram analisadas 78 espécies de plantas por GC-MS e UHPLC-UV(DAD)-MS(ESI-Orbitrap) nos modos positivo e negativo de ionização. As coletas de insetos foram feitas em intervalos trimestrais e, em seguida, esses insetos foram analisados utilizando a mesma metodologia analítica das plantas. As \"impressões digitais\" metabólicas das plantas e dos insetos foram precessadas no MetAlignTM e no MSClust, e as matrizes geradas foram submetidas a análises multivariadas no SIMCA. As plantas foram submetidas a análise de componentes principais (PCA), análise de cluster hierárquico (HCA) e análise discriminante ortogonal por mínimos quadrados parciais (OPLS-DA), entretanto os insetos, juntamente com suas plantas hospedeiras, foram analisados por PCA com o intuito de determinar a correlação entre seus metabólitos secundários. Os resultados das análises metabolômicas apresentaram proximidade com a filogenia principalmente para os dois maiors gêneros, Eremanthus e Lychnophora, analisados separadamente. Portanto, os resultados sugerem que os dados gerados a partir das análises metabolômicas podem ser utilizados em estudos quimiotaxonômicos da subtribo Lychnophorinae, sobretudo como dados primários para a reconstrução filogenética de gêneros. No que diz respeito às análises de possíveis interações inseto-planta, foi possível observar que alguns espécimens apresentaram correlação significativa com as plantas hospedeiras, evidenciando que a abordagem metabolômica pode ser utilizada como ferramenta na investigação de interações inseto-planta. Nestas amostras, pôde-se observar a presença de triterpenos, flavonoides e lactonas sesquiterpênicas adquiridas nas plantas por meio da herbivoria. / The subtribe Lychnophorinae occurs in the Cerrado domain of the Brazilian Central Plateau. The relationships among its recognized genera, as well as the relationships between Lychnophorinae and other subtribes belonging in tribe Vernonieae have been recently investigated upon a phylogeny based on molecular and morphological data. In addition, a preliminar overview of insect diversity in Brazilian Cerrado suggests that it may harbor a considerable fraction of the neotropical. We here report the use of a comprehensive untargeted metabolomics approach, combining LC-MS and GC-MS data together, followed by multivariate analyses aiming to assess the congruence between metabolomics data and the phylogenetic hypothesis, as well as its potential as a chemotaxonomic tool. Also we report the use of untargeted metabolomics approach aiming to assess insect-plant interactions. We analyzed 78 species by GC-MS and LC-MS in both positive and negative ionization modes. The metabolic profiles obtained for these species were treated in MetAlign and in MSClust and the matrices generated were combined and used in SIMCA for hierarchical cluster analyses (HCA), principal component analyses (PCA) and orthogonal partial least square discriminant analysis (OPLS-DA). The insects were collected quarterly and analyzed by the same analytical methods as plants. Results show that metabolomics analyses are mostly congruent with the phylogenetic hypothesis especially at lower taxonomic levels. Therefore, our results suggest that data generated by metabolomics approaches provide valuable evidence for chemotaxonomical studies of Lychnophorinae subtribe, in particular as primary data for phylogenetic reconstruction of lineages as genera. Regarding to insects, it was possible to observe significative correlations between some insects and their host plants. In these samples, were able to identify triterpenes, flavonoids and sesquiterpene lactones.