Soil organic matter (SOM) plays an important role in the global carbon cycle. Therefore, it is important to understand the stability of SOM, which is related to several processes. Its intrinsic properties may be related to its stability, for example black carbon is considered to be relatively resistant to degradation. In most soils, the dark horizons coincide with the superficial layers or horizons due to the greater accumulation of organic matter, but in the southern states of Brazil, the presence of soils with dark subsurface horizons is frequently observed. The dark subsurface horizon of these soils are similar to a sombric horizon. Aspects about its origin, formation and preservation have not yet been fully elucidated. The objective of this work is to understand the formation of \'sombric\' horizons in soils of the region from Tijucas do Sul (Paraná, Brazil). Five soil profiles were described and collected, from which three originate from a toposequence and contained a \'sombric\' horizon (P1-P3), a reference soil that is representative of the area (P5) and an intermediate soil (P4) that showed morphology between the reference soil and the soils with a \'sombric\' horizon. To this end SOM is studied for its molecular composition by the pyrolysis technique coupled to gas chromatography and mass spectrometry (pyrolysis-GC-MS). In addition, 13C isotopic composition (δ13C) and phytolytic composition were studied in order to understand paleoclimatic conditions. These results will be related to past environmental conditions using 14C dating techniques, and supported by classical soil analysis. The samples of the horizons were submitted to the SOM chemical fractionation, generating two fractions: extractable fraction with NaOH (EXT) and residue (RES). The morphology of the profiles showed an intense biological activity in A horizons and a wide distribution of microfragments of charcoals. The lateral continuity of \'sombric\' horizons in toposequence soils was also observed, which differentiated them (P1-P3) from buried A horizons. The distribution of SOM in the fractions studied was the same for the five profiles studied: EXT> RES. Products related to wildfires such as polyaromatics (PAHs; BC) were found in all profiles, but in greater relative abundance in the \'sombric\' horizons, indicating a higher incidence of fire during the formation of these horizons and these compounds can be related to the maintenance of dark color of the \'sombric\' horizons. In relation to the paleoclimatic conditions it was observed that the dark subsurface horizons were developed during the Mid-Holocene under vegetation composed mainly by C4 grasses with shrubs, evidencing a drier climate corresponding to a higher fire incidence. / A matéria orgânica do solo (MOS) desempenha um papel importante no ciclo global do carbono. Portanto, é importante entender a estabilidade da MOS, que está relacionada a vários processos. As suas propriedades intrínsecas podem estar relacionadas com a sua estabilidade, por exemplo, o \"black carbon\" é considerado relativamente resistente à degradação. Na maioria dos solos, os horizontes escuros coincidem com as camadas ou horizontes superficiais devido ao maior acúmulo de matéria orgânica, mas nos estados do sul do Brasil, a presença de solos com horizontes subsuperficiais escurecidos é frequentemente observada. O horizonte subsuperficial escurecido destes solos assemelha-se a um horizonte sômbrico. Aspectos sobre sua origem, formação e preservação ainda não foram totalmente elucidados. O objetivo deste trabalho é compreender a formação de horizontes \'sômbricos\' em solos da região de Tijucas do Sul (Paraná, Brasil). Foram descritos e coletados cinco perfis de solo, dos quais três estão localizados em uma topossequência e continham um horizonte similar ao sômbrico (P1-P3), um solo de referência representativo da área (P5) e um solo intermediário (P4) que apresentou uma morfologia entre o solo de referência e os solos com horizonte \'sômbrico\'. Para este fim, a MOS foi estudada pela sua composição molecular através da técnica de pirólise acoplada à cromatografia gasosa e espectrometria de massa (pirólise-GC-MS). Além disso, estudou-se a composição isotópica 13C (δ 13C) e a composição fitolítica, a fim de compreender as condições paleoclimáticas que foram relacionados com as condições ambientais passadas usando técnicas de datação com 14C, e suportados pelas análises clássicas de solo. As amostras dos horizontes foram submetidas ao fracionamento químico MOS, gerando duas frações: fração extraível com NaOH (EXT) e resíduo (RES). A morfologia dos perfis mostrou uma intensa atividade biológica nos horizontes A e uma ampla distribuição de microfragmentos de carvão. Observouse também a continuidade lateral de horizontes \'sômbricos\' em solos da topossequência (P1-P3), diferenciando-os dos horizontes A enterrados. A distribuição da MOS nas frações estudadas pela pirólise foi a mesma para os cinco perfis: EXT> RES. Os produtos relacionados a incêndios florestais como os poliaromáticos (PAHs, BC) foram encontrados em todos os perfis, mas em maior abundância relativa nos horizontes sômbricos, indicando uma maior incidência de incêndio durante a formação destes horizontes. Os PAHs podem estar relacionados com a manutenção da cor escura dos horizontes \'sômbricos\'. Em relação às condições paleoclimáticas observou-se que os horizontes subsuperficiais escurecidos foram desenvolvidos durante o Holoceno Médio sob vegetação composta principalmente por gramíneas C4 com arbustos, evidenciando um clima mais seco correspondente a maior incidência de incêndio.

The revision of the CEN/TR 15522-2:2012 methodology contains new biomarkers to facilitate forensic fingerprinting of the variety of oil types that can be a part of different crimes and the purpose of this project is to validate the biomarkers of the new methodology. Biomarkers were validated by examining corresponding diagnostic ratios compatibility with the internationally used sampling cloth, discriminating power, correlation and simulated weathering sensibility through GC-SIM-MS analysis followed by statistical evaluation with t-tests, diagnostic power, Pearson correlation matrices and MS-PW plots respectively. Results based on most of the diagnostic ratios showed good compatibility with the internationally used sampling cloth, expected patterns of biodegradation and photo-oxidation except for observed photo-oxidation of hydro PAHs and that normative ratios and informative ratios with high diagnostic powers, but with strong correlations for some of the tested ratios, could be identified in diesel oils. Due to delimitations however such as the limited number of oils with similar origins that were analyzed the results should be regarded as guidelines that can be expanded.

Neste trabalho, o método de extração em fase sólida (SPE) com análises por cromatografia gasosa acoplada à espectrometria de massas (GC-MS) foi desenvolvido para a determinação de levoglucosano em amostras de água de chuva da região de Ribeirão Preto-SP, Brasil. O monossacarídeo levoglucosano foi proposto como um marcador específico para queima de biomassa, uma vez que o mesmo é liberado durante a pirólise da celulose em temperaturas acima de 300ºC. Após a otimização das variáveis SPE, as melhores condições dentre as avaliadas foram as seguintes: cartuchos SPE recheados com a fase extratora quitosana (1,0 g), volume de amostra igual a 5,0 mL, vazão de 1,0 mL min-1, solvente de eluição: metanol (volume igual a 2,5 mL), sem a adição de sal. O método SPE/GC-MS para a determinação de levoglucosano em amostras de chuva apresentou faixa linear no intervalo de concentração de 0,05 µg mL-1 a 0,50 µg mL-1, r 0,9967, exatidão de 95 a 110% e precisão inter ensaios com coeficientes de variação (CV) menores que 15%, exceto para o limite de quantificação (0,05 µg mL-1) o qual apresentou CV inferior a 20%. Segundo as determinações (SPE/GC-MS) de levoglucosano em amostras de água de chuva coletadas no período 03/08/2011 à 09/04/2012, as concentrações médias de levoglucosano na safra de cana-de-açúcar são aproximadamente quatro vezes superior ao período de entressafra. Este fato é justificado pela elevada taxa de queima da palha da cana-de-açúcar na região de Ribeirão Preto-SP no período safra, e consequentemente, maior emissão de material particulado para a atmosfera incluindo levoglucosano, COD, entre outros. / In this work, the method of solid phase extraction (SPE) with gas chromatography - mass spectrometry (GC-MS) analysis was developed for the determination of levoglucosan in rainwater samples collected in the region of Ribeirão Preto-SP, Brazil. The monosaccharide levoglucosan (1,6-Anhydro--D- Glucopyranose) was proposed as a specific marker for biomass burning, since it is released during the pyrolysis of cellulose at temperatures above 300 ° C. After optimization of the SPE variables, the best conditions were found to be as follows: SPE cartridges filled with the extraction phase chitosan (1,0 g), sample volume equal to 5,0 mL, flow rate of 1,0 mL.min-1 and elution with methanol (volume of 2,5 mL) without added salt. The use of the method SPE/GC-MS for to determination of levoglucosan in rainwater samples was in the range of concentration going from 0,05 to 0,50 g.mL-1, r 0,9967. The accuracy was 95-110%, determination of the inter assay precision gare coefficients of variation (CV) less than 15%, except for the limit of quantification (0,05 g.mL-1), for which CV was less than 20%. According to SPE/GC-MS determinations of levoglucosan in rainwater samples collected between 03/08/2011 and 09/04/2012, the average concentrations of this compound found during the harvest of sugar cane were approximately four times those obtained during the off-season. This fact is explained by the high rate of sugar cane burning in Ribeirão Preto-SP during harvest, which culminates in larger emissions of particulate matter to the atmosphere, including levoglucosano and COD, among others.

Made available in DSpace on 2017-07-24T19:37:57Z (GMT). No. of bitstreams: 1 JULIANE MARIA BER.pdf: 4116262 bytes, checksum: 58a85b36bbcbe8e5b731b5c3d9014a71 (MD5) Previous issue date: 2007-12-14 / The aim of the present work was to carry out an ethnopharmacological survey of the vegetal species used by the inhabitants of the municipality of Céu Azul (located in the extreme west of the State of Paraná, Brazil). A specific questionnaire was used to get the referring data to the uses and ways of preparation of the species used as medicinal. During the interviews, the plant material (exsiccate) was collected in duplicate with the aid of the informers for posterior identification and deposit in the Museu Botânico Municipal de Curitiba. The uses of 47 species pertaining to 12 botanical families were surveyed in this field research. One of the main objectives of the present work was to evaluate the possible use of forest medicinal species in Céu Azul, especially because an extensive area of the municipality belongs to the National Park of the Iguaçu. However, th 47 plants cited by the population can be divided in a group with 42 exotic species and another one with only 6 Brazilian plants, and none of which is being removed from the reserve. The data base of The International Plant Names Index was used to prevent inappropriate botanical names and to verify the current use of synonyms. A survey of the scientific information on the chemical composition and bioactivity was carried out for each cited species. The main source of scientific information for this work was the data base of the Institute of Scientific Information and the Chemical Abstracts on-line. In general, the Céu Azul population makes use of medicinal plants sufficiently known in the scientific sense, but there is also the use of little studied species. For four of the cited species (Alternanthera bettzickiana, Alternanthera dentata, Plectranthus neochilus, Tradescantia pallida), we could not find any scientific reference on its bioactivity. The results of this survey have been concomitantly interpreted as indicative for the election of one of these species, sufficiently known for the Céu Azul population, for deepening of study in the chemistry area. The chemical composition of the essential oil of Plectranthus neochilus was determined using gas chromatography techniques coupled to mass spectrometry. The main components were the monoterpenes α-pinene (9.7), thujene (9.0), terpin-4-ol (4.8) and sabinene (4.7); the sesquiterpenes caryophyllene (19.9) and caryophyllene oxide (15.5); and the diterpene methyl communate (4.4). The presence of pinene and caryophyllene as principal components of the essential oil could be related to the traditional use of Plectranthus against stomach ache. Keywords: medicinal plants, Céu Azul, ethnopharmacology, Plectranthus neochilus, essential oil, GC-MS. / O presente trabalho teve por objetivo realizar um levantamento etnofarmacológico de espécies vegetais utilizadas pelos moradores do município de Céu Azul (localizado no extremo oeste do Paraná). Utilizou-se um questionário específico para obter os dados referentes aos usos e modos de preparo das espécies utilizadas como medicinais. Durante as entrevistas, o material vegetal (exsicata) foi coletado em duplicata com o auxílio dos informantes para posterior identificação e depósito no Museu Botânico Municipal de Curitiba. Na pesquisa de campo foi constatada a utilização de 47 espécies pertencentes a 12 famílias botânicas. Um dos principais propósitos do presente levantamento foi avaliar o possível uso de espécies medicinais florestais no município de Céu Azul, especialmente porque uma extensa área do município pertence ao Parque Nacional do Iguaçu. No entanto, as 47 plantas citadas pela população ceuazulense podem ser divididas em um grupo com 42 espécies exóticas e outro com apenas 6 plantas brasileiras, nenhuma das quais é retirada da reserva. Utilizou-se o banco de dados do The International Plant Names Index para evitar incorreções nos binômios botânicos e verificar o uso atual de sinônimos. Para cada espécie citada, foi realizado um levantamento das informações científicas sobre a composição química e a bioatividade. As principais fontes de informações científicas foram o banco de dados do Institute for Scientific Information e o Chemical Abstracts on-line. Em geral, a população de Céu Azul faz uso de plantas medicinais bastante conhecidas no meio científico, mas há também a utilização de espécies pouco estudadas. Para quatro das espécies utilizadas (Alternanthera bettzickiana, Alternanthera dentata, Plectranthus neochilus, Tradescantia pallida), não foram encontradas referências científicas sobre suas bioatividades. Desta forma, os resultados deste levantamento foram concomitantemente interpretados como indicativos para a seleção de uma destas espécies, bastante conhecida e utilizada pela população de Céu Azul, para aprofundamento de estudo, Plectranthus neochilus. Determinou-se a composição química do óleo essencial das folhas desta espécie vegetal por técnicas de cromatografia gasosa acoplada à espectrometria de massas. Os principais componentes encontrados foram os monoterpenos pineno (9,7), tujeno (9,0), terpinen-4-ol (4,8) e sabineno (4,7); os sesquiterpenos cariofileno (19,9) e óxido de cariofileno (15,5); e o diterpeno comunato de metila (4,4). A ocorrência de pineno e cariofileno como principais componentes do óleo essencial pode estar relacionada ao uso tradicional desta espécie vegetal contra dores estomacais.

Made available in DSpace on 2017-07-24T19:38:01Z (GMT). No. of bitstreams: 1 Elementos pre-textuais.pdf: 567197 bytes, checksum: b26ed97be7d0d26d6ba01f298cc6bef8 (MD5) Previous issue date: 2009-06-29 / This study aimed to chemically analyze extracts of propolis samples and leaves of plant species of the Baccharis genus in the region of Ponta Grossa - PR, to classify the regional propolis compared to the green propolis (PG12). Baccharis dracunculifolia, the source of green propolis, may present metabolic changes related to environmental factors. To compare with published data, the essential oils obtained by hydrodistillation from the leaves of female (0.81%) and male (0.85%) specimens of B. dracunculifolia harvested in the dry season were analyzed by GC-MS. The two samples showed a low monoterpenes/sesquiterpenes ratio (0.85/96.88% ♀; 2.35/ 95.25% ♂). The monoterpenes b-pinene, limonene and terpinen-4-ol were identified. The main sesquiterpenes hydrocarbons are b-caryophyllene (♀ 7.88%; ♂ 8.88%), b-humulene (♀ 4.61%; ♂ 2.18%), germacrene D (♀ 5.53%; ♂ 4.04%) trans-b- guaiene (♀ 7.98%; ♂ 6.06%) and cadinene (♀ 7.34%; ♂ 5.48%). The oxygenated sesquiterpenes (E)-nerolidol (♀ 24.69%; ♂ 17.16%) and spathulenol (♀ 14.62%; ♂ 21.39%) were found as the major constituents. The high yield, the low monoterpenes / sesquiterpenes ratio and the high proportions of oxygenated sesquiterpenes are the main characteristics of the essential oil of B. dracunculifolia from this region. The leaves of three species of Baccharis (B. dracunculifolia, B. semiserrata and B. uncinella) were extracted using a Soxhlet apparatus with the sequence of solvents chloroform, ethyl acetate and methanol, and the extracts were analyzed by TLC, UV and HPLC. Free phenolic acids were identified: caffeic acid (Bd ♀ and Bd ♂), p-coumaric acid (Bd ♀), ferulic acid (Bd ♀, ♂ Bd, Bu and Bs) and the flavonoid rutin (Bd ♀, Bd ♂, Bu). Thus, it is demonstrated for the first time, the co-occurrence of polar phenolic substances in these three plant species. The ethanol extracts obtained from 13 samples of propolis were analyzed by TLC-HR and UV-VIS, allowing the classification of the regional propolis in three groups. The most characteristic sample of each type (ADI, WS- 3, RS-2) was chosen for analysis by HPLC in comparison with green propolis PG12. Fresh sprouts of male and female specimens of B. dracunculifolia were extracted by rinsing with methanol and the extracts were analyzed by HPLC. All extracts of propolis and B. dracunculifolia showed artepillin C ensuring that this plant is the source of regional propolis. The caffeic acid, ferulic acid and p-coumaric acid were identified in the four samples of propolis. Apigenin is present only in the regional propolis samples, between 2.4% and 3.9%, while crisin was identified only in the PG12, but as a main component (18.1%). An unidentified flavonoid (lma x 365 nm, 42,96 min) is the main substance present in the three samples of regional propolis and also the extract obtained by the rinsing of the plant sprouts. All the ethanol extracts of regional propolis showed excellent levels of antioxidant activity when tested against the radical DPPH, several of them getting to be more effective than the PG12. A comparative analysis of antioxidant power and chemical composition of the samples indicates that the unidentified flavonoid is responsible for the strong antioxidant activity of ADI and WS-2 compared to RS-2 and PG12. / Neste trabalho, foram analisados extratos de amostras de própolis e de folhas de espécies vegetais do gênero Baccharis da região de Ponta Grossa – PR, visando classificar a própolis regional em comparação com a própolis verde (PG12). Baccharis dracunculifolia, a fonte da própolis verde, pode apresentar variações metabólicas relacionadas a fatores ambientais. Para comparar dados publicados sobre esta planta com dados obtidos do vegetal coletado nesta região, foram analisados por CG-EM os óleos essenciais obtidos por hidrodestilação das folhas de espécimes feminino (0,81%) e masculino (0,85%) de B. dracunculifolia colhidos na estação seca. As duas amostras apresentaram baixa razão monoterpenos/sesquiterpenos (0,85/96,88% ♀; 2,35/95,25% ♂). Foram identificados os monoterpenos b-pineno, limoneno e terpinen-4-ol. Os sesquiterpenos hidrocarbonetos principais foram: b-cariofileno (♀ 7,88%;♂ 8,88%), a-humuleno (♀ 4,61%; ♂ 2,18%), germacreno D (♀ 5,53%; ♂ 4,04%), trans-b- guaieno (♀ 7,98%; ♂ 6,06%) e d-cadineno (♀ 7,34%; ♂5,48%). Os sesquiterpenos oxigenados (E)-nerolidol (♀ 24,69%; ♂ 17,16%) e espatulenol (♀ 14,62%; ♂ 21,39%) se encontraram como constituintes majoritários. O alto rendimento, a baixa relação monoterpenos/sesquiterpenos e as altas proporções de sesquiterpenos oxigenados são as principais características do óleo essencial de B. racunculifolia desta região. As folhas de três espécies de Baccharis (B. dracunculifolia, B. semiserrata e B. uncinella) foram extraídas em aparelho Soxhlet com a sequência de solventes clorofórmio, acetato de etila e metanol, analisando-se os extratos por CCD, UV e CLAE. Foram dentificados os ácidos fenólicos livres: ácido caféico (Bd ♀ e Bd ♂), ácido p-cumárico (Bd ♀), ácido ferúlico (Bd ♀, Bd ♂, Bu e Bs) e o flavonóide rutina (Bd ♀, Bd ♂, Bu). Assim, demostrou-se, pela primeira vez, a co-ocorrência de substâncias fenólicas polares nestas três espécies vegetais. Os extratos etanólicos obtidos de 13 amostras de própolis foram analisados por CCD-AR e UV-VIS, permitindo classificar as própolis regionais em três grupos. Foi escolhida a amostra mais característica de cada grupo (ADI, WS-3, RS-2) para análise por CLAE em comparação com a própolis verde PG12. Brotos frescos dos espécimes masculino e feminino de B. dracunculifolia foram extraídos por enxágüe com metanol e também submetidos à análise por CLAE. Todos os extratos, de própolis e de B. dracunculifolia, apresentaram artepilina C garantindo que esta é a fonte vegetal da própolis regional. Os ácidos caféico, ferúlico e pcumárico foram identificados nas quatro amostras de própolis. Apigenina estaria presente somente nas própolis regionais, entre 2,4% e 3,9%, enquanto a crisina foi identificada somente na PG12, mas como componente principal (18,1%). Um flavonoide (lmáx 365 nm, 42,96 min) é a substância principal das três amostras de própolis regionais e também do extrato obtido por enxágue dos brotos da planta, mas não foi identificado. Todos os extratos etanólicos de própolis regionais apresentaram excelentes níveis de atividade antioxidante quando testados frente ao radical DPPH, vários deles chegando a ser mais efetivos que o da PG12. Uma análise comparativa do poder antioxidante e da composição química das amostras permitem concluir que o flavonóide não identificado é o responsável pela fortíssima atividade antioxidante de ADI e WS-2 em comparação com RS-2 e PG12.

Les exsudats des plantes sont des substances naturelles complexes. Ils sont utilisés par plusieurs populations d’Afrique et trouvent de nombreuses applications : en thérapeutique, en pharmacie galénique, en parfumerie, etc. Au Congo, une grande majorité de ces substances est encore mal connue. Ce travail de thèse a consisté à inventorier les plantes à exsudats du Congo et à mettre au point une méthodologie d’analyse physico-chimique permettant la caractérisation des exsudats d’arbres d’origine botanique certifiée.La méthodologie d’inventaire adoptée nous a permis de recenser 135 plantes à exsudats appartenant à 87 genres. Il en ressort de cette étude que les exsudats des plantes inventoriées ont multiples usages (glu, insectifuge, allume-feu, antidouleur, etc.).La stratégie mise en place pour leur caractérisation fait appel à plusieurs techniques analytiques (SPIR, SMIR, CPG-SM, GCxGC-MS) et de traitement d’échantillon (Hs-SPME, hydrodistillation, extraction au Soxhlet, silylation, méthylation, pyrolyse). Dans le cadre de ce travail deux exsudats ont été caractérisés. L’exsudat de D. edulis (G. Don) K.J. Lam qui est constitué de monoterpènes hydrocarbonés et de triterpènes, dont les majeurs sont : 3-épi-α et -β-amyrine. L’exsudat de G. demeusei (Harms) J. Léonard dont la fraction volatile est constituée essentiellement de sesquiterpènes et la fraction peu-volatile d’acides diterpéniques de type labdane (acide éperuique, cativique, copalique, ozique, etc.).Pour exploiter l’efficacité de séparation élevée de la GCxGC-MS, nous nous sommes confronté aux problèmes de la non-répétabilité des cartes chromatographiques obtenues en 2D. Nous avons alors mis en place une méthodologie permettant de vérifier l’épaisseur de film et l’homogénéité des dépôts de phases stationnaires afin de sélectionner des colonnes courtes identiques pour la GCxGC. Cependant, les résultats préliminaires ont montré que même avec des colonnes de deuxième dimension identiques, on pouvait avoir des différences au niveau de carte 2D. / Plant exudates are natural complex substances. They are used by several populations in Africa and have many applications: in therapeutics, in galenic pharmacy, in perfumery, etc. In Congo, a great majority of these substances are not yet well known. This thesis work aimed to make an inventory of plant exudates from Congo and to develop a methodology for performing physico-chemical analysis which may enable characterization of exudates from botanical certified trees.Through the methodology that we developed, 135 plant exudates belonging 87 genera were registered. It was observed in this study that these exudates are used for many purposes (glue, insect repellent, making fire, anti-pain, etc).The strategy implemented for characterizing the exudates included several analytical (SNIR, SMIR, GC-MS, GCxGC-MS) and sample processing (Hs-SPME, hydrodistillation, extraction using the Soxhlet, silylation, methylation pyrolyse) techniques. With regard to this work, two exudates were characterized. The exudates from D. edulis (G. Don) K.J. Lam which contained monoterpene hydrocarbons and triterpenes, with the major constituents being: 3-epi-α and -β-amyrine. The exudates from G. Demeusei (Harms) J. Léonard was found to have the sesquiterpenes as major constituents of the volatile fraction and the labdane-type diterpenes (eperuique acide, cativique acid, copalique acid, ozique acid, etc) as major constituents of the poor-volatile fraction.To explore the efficacy of elevated separation of the GCxGC-MS, we faced some problems related to the non-repeatability of chromatographic cards obtained in 2D. Therefore, we put in place a methodology which enables us to verify the film thickness and homogeneity of layers of stationary phases in order to select identical short columns for GCxGC. However, the preliminary results have shown that even using second identical dimension columns, we could observed differences in 2D cards

Soil organic matter (SOM) plays an important role in the global carbon cycle. Therefore, it is important to understand the stability of SOM, which is related to several processes. Its intrinsic properties may be related to its stability, for example black carbon is considered to be relatively resistant to degradation. In most soils, the dark horizons coincide with the superficial layers or horizons due to the greater accumulation of organic matter, but in the southern states of Brazil, the presence of soils with dark subsurface horizons is frequently observed. The dark subsurface horizon of these soils are similar to a sombric horizon. Aspects about its origin, formation and preservation have not yet been fully elucidated. The objective of this work is to understand the formation of \'sombric\' horizons in soils of the region from Tijucas do Sul (Paraná, Brazil). Five soil profiles were described and collected, from which three originate from a toposequence and contained a \'sombric\' horizon (P1-P3), a reference soil that is representative of the area (P5) and an intermediate soil (P4) that showed morphology between the reference soil and the soils with a \'sombric\' horizon. To this end SOM is studied for its molecular composition by the pyrolysis technique coupled to gas chromatography and mass spectrometry (pyrolysis-GC-MS). In addition, 13C isotopic composition (δ13C) and phytolytic composition were studied in order to understand paleoclimatic conditions. These results will be related to past environmental conditions using 14C dating techniques, and supported by classical soil analysis. The samples of the horizons were submitted to the SOM chemical fractionation, generating two fractions: extractable fraction with NaOH (EXT) and residue (RES). The morphology of the profiles showed an intense biological activity in A horizons and a wide distribution of microfragments of charcoals. The lateral continuity of \'sombric\' horizons in toposequence soils was also observed, which differentiated them (P1-P3) from buried A horizons. The distribution of SOM in the fractions studied was the same for the five profiles studied: EXT> RES. Products related to wildfires such as polyaromatics (PAHs; BC) were found in all profiles, but in greater relative abundance in the \'sombric\' horizons, indicating a higher incidence of fire during the formation of these horizons and these compounds can be related to the maintenance of dark color of the \'sombric\' horizons. In relation to the paleoclimatic conditions it was observed that the dark subsurface horizons were developed during the Mid-Holocene under vegetation composed mainly by C4 grasses with shrubs, evidencing a drier climate corresponding to a higher fire incidence. / A matéria orgânica do solo (MOS) desempenha um papel importante no ciclo global do carbono. Portanto, é importante entender a estabilidade da MOS, que está relacionada a vários processos. As suas propriedades intrínsecas podem estar relacionadas com a sua estabilidade, por exemplo, o \"black carbon\" é considerado relativamente resistente à degradação. Na maioria dos solos, os horizontes escuros coincidem com as camadas ou horizontes superficiais devido ao maior acúmulo de matéria orgânica, mas nos estados do sul do Brasil, a presença de solos com horizontes subsuperficiais escurecidos é frequentemente observada. O horizonte subsuperficial escurecido destes solos assemelha-se a um horizonte sômbrico. Aspectos sobre sua origem, formação e preservação ainda não foram totalmente elucidados. O objetivo deste trabalho é compreender a formação de horizontes \'sômbricos\' em solos da região de Tijucas do Sul (Paraná, Brasil). Foram descritos e coletados cinco perfis de solo, dos quais três estão localizados em uma topossequência e continham um horizonte similar ao sômbrico (P1-P3), um solo de referência representativo da área (P5) e um solo intermediário (P4) que apresentou uma morfologia entre o solo de referência e os solos com horizonte \'sômbrico\'. Para este fim, a MOS foi estudada pela sua composição molecular através da técnica de pirólise acoplada à cromatografia gasosa e espectrometria de massa (pirólise-GC-MS). Além disso, estudou-se a composição isotópica 13C (δ 13C) e a composição fitolítica, a fim de compreender as condições paleoclimáticas que foram relacionados com as condições ambientais passadas usando técnicas de datação com 14C, e suportados pelas análises clássicas de solo. As amostras dos horizontes foram submetidas ao fracionamento químico MOS, gerando duas frações: fração extraível com NaOH (EXT) e resíduo (RES). A morfologia dos perfis mostrou uma intensa atividade biológica nos horizontes A e uma ampla distribuição de microfragmentos de carvão. Observouse também a continuidade lateral de horizontes \'sômbricos\' em solos da topossequência (P1-P3), diferenciando-os dos horizontes A enterrados. A distribuição da MOS nas frações estudadas pela pirólise foi a mesma para os cinco perfis: EXT> RES. Os produtos relacionados a incêndios florestais como os poliaromáticos (PAHs, BC) foram encontrados em todos os perfis, mas em maior abundância relativa nos horizontes sômbricos, indicando uma maior incidência de incêndio durante a formação destes horizontes. Os PAHs podem estar relacionados com a manutenção da cor escura dos horizontes \'sômbricos\'. Em relação às condições paleoclimáticas observou-se que os horizontes subsuperficiais escurecidos foram desenvolvidos durante o Holoceno Médio sob vegetação composta principalmente por gramíneas C4 com arbustos, evidenciando um clima mais seco correspondente a maior incidência de incêndio.

<p>This thesis is based on studies in which the suitability of various gas chromatography (GC) injection techniques was examined for the determination of polybrominated diphenyl ethers (PBDEs) and carbazoles, two groups of compounds that are thermally labile and/or have high boiling-points. For such substances, it is essential to introduce the samples into the GC system in an appropriate way to avoid degradation and other potential problems. In addition, different types of gas chromatographic column system and mass spectrometric detectors were evaluated for the determination of PBDEs.</p><p>Conventional injectors, such as splitless, on-column and programmed temperature vaporizing (PTV) injectors were evaluated and optimized for determination of PBDEs. The results show on-column injection to be the best option, providing low discrimination and high precision. The splitless injector is commonly used for “dirty” samples. However, it is not suitable for determination of the high molecular weight congeners, since it tends to discriminate against them and promote their degradation, leading to poor precision and accuracy. The PTV injector appears to be a more suitable alternative. The use of liners reduces problems associated with potential interferents such as polar compounds and lipids and compared to the hot splitless injector, it provides gentler solvent evaporation, due to its temperature programming feature, leading to low discrimination and variance.</p><p>Increasing the injection volume from the conventional 1-3 µL to >50 µL offers two main benefits. Firstly, the overall detection and quantification limits are decreased, since the entire sample extract can be injected into the GC system. Secondly, large volume injections enable hyphenation of preceding techniques such as liquid chromatography (LC), solid phase extraction and other kinds of extraction. Large-volume injections were utilized and optimized in the studies included in this thesis.</p><p>With a loop-type injector/interface large sample volumes can be injected on-column providing low risk of discrimination against compounds with low volatility. This injector was used for the determination of PBDEs in air and as an interface for the determination of carbazoles by LC-GC. Peak distortion is a frequently encountered problem associated with this type of injector that was addressed and solved during the work underlying this thesis.</p><p>The PTV can be used as a large volume injector, in so-called solvent vent mode. This technique was evaluated for the determination of PBDEs and as an interface for coupling dynamic sonication-assisted solvent extraction online to GC. The results show that careful optimization of the injection parameters is required, but also that the PTV is robust and yields reproducible results.</p><p>PBDEs are commonly detected using mass spectrometry in electron capture negative ionization (ECNI) mode, monitoring bromine ions (m/z 79 and 81). The mass spectrometric properties of the fully brominated diphenyl ether, BDE-209, have been investigated. A high molecular weight fragment at m/z 486/488 enables the use of 13C-labeled BDE-209 as an internal surrogate standard.</p>

English: Semiochemicals informative molecules used in insect-insect or plant-insect interactions have been widely considered within various integrated pest management (IPM) strategies. In the present thesis, two sesquiterpenoids, E-β-farnesene and E-β-caryophyllene, were formulated for their related properties as aphid enemy attractants. E-β-farnesene, the alarm pheromone of many aphid species, was also identified as a kairomone by attracting and inducing oviposition of aphid predators (Episyrphus balteatus De Geer (Diptera: Syrphidae)) and by attracting aphid parasitoids (Aphidius ervi Haliday (Hymenoptera: Braconidae)). E-β-caryophyllene was identified as a potential component of the aggregation pheromone of the Asian ladybird, Harmonia axyridis Pallas, another aphid predator. The two products were purified from essential oils of Matricaria chamomilla L. (Asteraceae) and Nepeta cataria L. (Lamiaceae) for E-β-farnesene and E-β-caryophyllene, respectively. Natural and biodegradable slow-release formulations were then investigated in order to deliver these molecules on crop fields for a long period of time as biological control devices. Due to their sensitivity to oxidation, both sesquiterpenes needed to be protected from oxygen degradation. For this purpose, alginate hydrophilic matrix with low oxygen permeability was used as polymer for the formulations: the main objective was to deliver semiochemical substances in the air in a controlled way. Consequently, a careful selection of alginates was realised. Formulated beads showed different structural and encapsulation properties depending on various formulation factors. Alginate formulations were characterized by texturometry and by confocal microscopy in order to observe the distribution of semiochemicals in alginate network. The last step of alginate bead characterisation consisted in studying release rate of semiochemicals in laboratory-controlled conditions by optimised trapping and validated Fast-GC procedures. Finally, the efficiency of formulations as aphid predator (Syrphidae) and parasitoids (A. ervi) attractants was demonstrated by field trapping and olfactometry experiments. Français: Les sémiochimiques molécules véhiculant des informations au sein des interactions insecte-insecte ou plante-insecte ont été largement utilisés dans de nombreuses stratégies de lutte intégrée. La présente thèse de doctorat décrit la formulation de deux sesquiterpènes, le E-β-farnésène et le E-β-caryophyllène, pour leurs propriétés relatées dans la littérature en tant quattractants des ennemis des pucerons. En effet, le E-β-farnésène, la phéromone dalarme de nombreuses espèces de pucerons, a également été identifié comme kairomone en attirant des parasitoïdes (Aphidius ervi Haliday (Hymenoptera: Braconidae)) et des prédateurs de pucerons (Episyrphus balteatus De Geer (Diptera: Syrphidae)) et en induisant un comportement doviposition chez ces derniers. Le E-β-caryophyllène a récemment été identifié comme un composé probable de la phéromone dagrégation des coccinelles asiatiques, Harmonia axyridis Pallas, également prédatrices de pucerons. Les deux produits ont été purifiés au départ des huiles essentielles de Matricaria chamomilla L. (Asteraceae) et de Nepeta cataria L. (Lamiaceae) respectivement dans le cas du E-β-farnésène et du E-β-caryophyllène. Des formulations biodégradables et dorigine naturelle ont ensuite été développées comme outil de contrôle biologique afin de libérer les deux composés de façon progressive. En raison de leur sensibilité à loxydation, ces deux sesquiterpènes devaient être protégés de loxygène. A cette fin, de lalginate matrice hydrophile offrant une faible perméabilité à loxygène a été utilisé comme polymère de formulation : le principal objectif était de délivrer les substances sémiochimiques dans lair dune façon contrôlée. En conséquence, lalginate a été sélectionné de façon minutieuse. Les billes formulées ont montrés des propriétés structurelles et dencapsulation différentes en fonction de nombreux facteurs intervenant lors de la formulation. Les formulations ont été caractérisées par texturométrie et par microscopie confocale de façon à observer la distribution des sémiochimiques au sein du réseau dalginate. La dernière étape de caractérisation des billes a consisté en létude du taux de libération des sémiochimiques dans des conditions contrôlées de laboratoire après avoir optimisé la technique de piégeage des volatils et validé la procédure danalyse par GC rapide. Finalement, lefficacité dattraction des formulations envers les prédateurs et les parasitoïdes de pucerons a été démontrée par des expériences de piégeage sur cultures et des essais dolfactométrie.

From its first use in the field of biochemistry, instrumental analysis offered a variety of invaluable tools for the comprehensive description of biological systems. Multi-selective methods that aim to cover as many endogenous compounds as possible in biological samples use different analytical platforms and include methods like gene expression profile and metabolite profile analysis. The enormous amount of data generated in application of profiling methods needs to be evaluated in a manner appropriate to the question under investigation. The new field of system biology rises to the challenge to develop strategies for collecting, processing, interpreting, and archiving this vast amount of data; to make those data available in form of databases, tools, models, and networks to the scientific community.<br><br> On the background of this development a multi-selective method for the determination of phytohormones was developed and optimised, complementing the profile analyses which are already in use (Chapter I). The general feasibility of a simultaneous analysis of plant metabolites and phytohormones in one sample set-up was tested by studies on the analytical robustness of the metabolite profiling protocol. The recovery of plant metabolites proved to be satisfactory robust against variations in the extraction protocol by using common extraction procedures for phytohormones; a joint extraction of metabolites and hormones from plant tissue seems practicable (Chapter II).<br><br> Quantification of compounds within the context of profiling methods requires particular scrutiny (Chapter II). In Chapter III, the potential of stable-isotope in vivo labelling as normalisation strategy for profiling data acquired with mass spectrometry is discussed. First promising results were obtained for a reproducible quantification by stable-isotope in vivo labelling, which was applied in metabolomic studies.<br><br> In-parallel application of metabolite and phytohormone analysis to seedlings of the model plant Arabidopsis thaliana exposed to sulfate limitation was used to investigate the relationship between the endogenous concentration of signal elements and the ‘metabolic phenotype’ of a plant. An automated evaluation strategy was developed to process data of compounds with diverse physiological nature, such as signal elements, genes and metabolites – all which act in vivo in a conditional, time-resolved manner (Chapter IV). Final data analysis focussed on conditionality of signal-metabolome interactions. / Die instrumentelle Analytik stellt mit ihrem unschätzbaren Methodenreichtum Analysenwerkzeuge zur Verfügung, die seit ihrem Einzug in die Biologie die Aufzeichnung immer komplexerer ‚Momentaufnahmen’ von biologischen Systemen ermöglichen. Konkret hervorzuheben sind dabei vor allem die sogenannten ‚Profilmethoden’. Die Anwendung von Profilmethoden zielt darauf ab, aus einer bestimmten Stoffklasse so viele zugehörige Komponenten wie nur möglich gleichzeitig zu erfassen. <br><br> Für die Auswertung derart komplexer Daten müssen nun auch entsprechende Auswertungsmethoden bereit gestellt werden. Das neu entstandene Fachgebiet der Systembiologie erarbeitet deshalb Strategien zum Sammeln, Auswerten und Archivieren komplexer Daten, um dieses gesammelte Wissen in Form von Datenbanken, Modellen und Netzwerken der allgemeinen Nutzung zugänglich zu machen.<br><br> Vor diesem Hintergrund wurde den vorhandenen Profilanalysen eine Methode zur Erfassung von Pflanzenhormonen hinzugefügt. Verschiedene Experimente bestätigten die Möglichkeit zur Kopplung von Pflanzenhormon- und Pflanzeninhaltsstoff(=metabolit)-Profilanalyse. In weiteren Untersuchungen wurde das Potential einer innovativen Standardisierungstechnologie für die mengenmässige Erfassung von Pflanzeninhaltsstoffen in biologischen Proben betrachtet (in vivo labelling mit stabilen Isotopen).<br><br> Hormon- und Metabolitprofilanalyse wurden dann parallel angewandt, um Wechselwirkungen zwischen der Konzentration von Signalkomponenten und der Ausprägung des Stoffwechsels in Keimlingen der Modellpflanze Arabidopsis thaliana zu untersuchen. Es wurde eine Prozessierungsmethode entwickelt, die es auf einfache Art und Weise erlaubt, Daten oder Komponenten verschiedenen Ursprungs wie Signalelemente, Gene und Metabolite, die in biologischen Systemen zeitlich versetzt aktiv oder verändert erscheinen, im Zusammenhang zu betrachten. Die abschließende Analyse aller Daten richtet sich auf die Abschätzung der Bedingtheit von Signal-Metabolismus Interaktionen.