The master thesis deals with comparison of atomic fluorescence spektrometry and high resolution continuum source atomic absorption spektrometry for three methods generation of volatile compounds Antimony. In both methods of atomic antimony detection, it compares the most common chemical generation of volatile compounds (hydrides) with two alternative methods - electrochemical and UV - photochemical. The values of performance parameters for the determination of Sb(III) and Sb(V) were determined for all the above combinations. In the case of chemical generation, a surprisingly almost four times higher limit of detection of Sb(III) was found in connection with AFS detection than AAS detection. The final part was devoted to UV - photochemical vapor generation, with AAS detection for Sb(III) reaching limit of detection 4,96 ppb, for Sb(V) 8,63 ppb. Although UV - photochemical generation of volatile antimony compounds did not reach such performance parameters as chemical or electrochemical generation, it was observed that the sensitivity of antimony determination increased greatly when introducing oxygen into the apparatus. The interference study also found a significant positive effect of Fe(II) on the generation efficiency, and this modification partially persisted without further introduction of these...

Previously, selenium was known as an element with negative properties. However, in the last century, the significant positive effects on human health were detected. Currently, the function, behavior and toxicity of selenium are still not well known. The key to understand it is to do speciation analysis. The aim of this diploma thesis is to develop method for determination inorganic (sodium selenite and selenate) and organic (selenourea, selenocystine, selenomethionine) selenium compounds. Parameters of apparatus for electrochemical hydride generation with atomic absorption spectrometry detector were optimized, final conditions were set and optimal conditions for separation process using HPLC were investigated. Calibration dependences for selenium compounds were measured and analytical figures of merit were investigated. In conclusion, a coupled method HPLC- EcHG- QFAAS for determination of individual selenium compounds was proposed, and it was tested on urea samples. Calibrations for these measurements were investigated and analytic characteristics were calculated. Based on these comparisons it can be said that proposed method allows the determination of selected selenium compounds in both aqueous and urea matrices. Subject words: Spectroscopy, analytical chemistry Key words: Atomic absorption...

Anopheles gambiae sensu lato mosquitoes are among the dominant malaria vectors in sub-Saharan Africa. However, not much is known about the oviposition behaviour of these species necessary for the development of malaria vector control strategies. With the aim of investigating cues associated with selected oviposition sites, artificial oviposition sites- ponds (soil mixed with water) were set-up in an open field at Mbita, Western Kenya in 2012 and 2013. Ponds were allowed to be colonized by wild An. gambiae s.l.. The numbers of Anopheles early instar larvae were counted and used as a proxy for oviposition preference. Water samples were then analysed for physicochemical, bacterial and chemical profiles. The bacterial profiles were analysed using denaturing gradient gel electrophoresis (DGGE) and the chemical profiles with gas chromatography-mass spectrometry (GC-MS). The detection of possible oviposition cues from oviposition substrates requires sensitive analytical methods. Volatiles detection was improved seven times. The detection of bacteria deoxyribonucleic acid (DNA) bands with DGGE was also improved to a minimum DNA concentration of 50 ng/µl. Results showed that ponds were colonized differently. Fresh ponds were preferred over slightly older ponds. Bacterial analysis revealed a low number of bacteria colony forming units (CFU) in preferred ponds. Some volatiles, including: 6,10-dimethyl-5,9-undecadien-2-one (geranylacetone) and 4-ethylbenzaldehyde, were associated with the oviposition preferred pond. In addition, low pH and high turbidity were associated with the ponds selected for oviposition. Finally, fungi isolated from the rhizomes of nut grass yielded a promising array of volatiles of which one is known to attract oviposition site seeking malaria mosquitoes. This finding opens the door for a cost effective and environmental friendly method of using fungi in an “attract and kill” strategy targeting malaria vectors. / Myggor i Anopheles gambiae sensu lato komplexet tillhör de myggor som är bäst på att sprida malaria parasiter i afrika söder om Sahara. Kunskapen om de här myggornas äggläggningsbeteende är begränsad. Den här kunskapen behövs för att kunna utveckla nya och förbättra tillgängliga malaria vektor kontroll metoder. Nya metoder som kan komplettera de som används idag (insecticides treated nets (ITNs) och indoor residual spraying (IRS)) behövs eftersom de metoderna har problem med resistensutveckling. Två studier utfördes på icipe fältstation i Mbita västra Kenya under 2012 och 2013 med målet att identifiera faktorer som påverkar myggornas äggläggningsbeteende. Baljor fyllda med en blandning av jord och vatten (äggläggningssubstrat) användes för att tillverka artificiella äggläggningsplatser som liknar de vattenpölar som de här myggarterna gärna lägger ägg i. Baljorna koloniserades av vilda myggor och antalet mygglarver som detekterades i baljorna jämfördes och användes som en proxy för äggläggningspreferens. Fysikaliska och kemiska parametrar mättes på jordvattenblandningarna i baljorna och prover togs för att analysera bakteriepopulationer med hjälp av denaturing gradient gel electrophoresis (DGGE) och flyktiga ämnen med hjälp av gas-kromatografi kopplat till mass-spektrometri (GC-MS). För att kunna detektera de låga halter av flyktiga ämnen och bakterier som fanns i de här proverna krävdes det känsliga metoder. Antalet flyktiga ämnen som kunde detekteras ökades sju gånger genom att tillsätta NaCl till vattenproverna innan doften insamlades och termisk desorption användes istället för lösningsmedels desorption. För att förbättra detektionsgränsen för bakterier amplifierades bakterie-DNA i två PCR reaktioner som sedan mixades och koncentrerades. Resultaten från fältstudierna med baljorna visade att de koloniserades olika av Anopheles myggorna. Baljor med nyblandat substrat innehöll dubbelt så många mygglarver som baljor med jord-vattensubstrat som åldrats under en längre tid. Lägre mängd bakterier, lägre pH och högre grumlighet var gemensamt för de baljor som myggorna föredrog. De flyktiga ämnen som detekterades i de olika baljor varierade mellan olika försök och inget ämne fanns med i alla upprepningar av ett försök. Trots det detekterades några ämnen oftare i de baljor som myggorna föredrog att lägga ägg jämfört med de med en mindre mängd mygglarver. De inkluderar geranylacetone och 4-ethylbenzaldehyde. Svampar isolerades från rotstockar av gräs som fanns i den jord som användes för att göra äggläggningssubstraten i fältstudierna. De flyktiga ämnen som avgavs från svampkulturerna analyserades. Bland annat så identifierades ett ämne som fungerar som en äggläggningsattrahent för An. gambiae s.l. myggor.Resultaten från den här avhandlingen kommer att kunna användas för att utveckla miljövänliga ”attract and kill” metoder för att kontrollera malaria myggor. / <p>QC 20160211</p>

O Brasil apresenta grande potencial para a exploração da apicultura, dado ao seu vasto território e flora diversificada, o que permite diferentes variedades de méis com propriedades únicas. O estado do Paraná é um dos maiores produtores de méis do país e o investimento em produção que atenda aos mercados mais exigentes estimulou a produção do mel orgânico. O conhecimento desde a antiguidade sobre os efeitos benéficos à saúde pelo mel vem estimulando a pesquisa deste alimento nobre. Assim, este trabalho teve por objetivo estudar méis orgânicos brasileiros certificados (MO) para a caracterização do perfil fenólico, volátil, além da avaliação da capacidade de sequestro das espécies reativas de oxigênio e nitrogênio. Os méis foram coletados nos apiários de apicultores com certificação orgânica de dois municípios do sul do Paraná, General Carneiro e Turvo-PR. Nos ensaios foram utilizados extratos fenólicos dos méis, obtidos por meio da utilização da resina Amberlite® XAD®2, bem como méis brutos in natura. Os extratos apresentaram conteúdo de compostos fenólicos significativo, sendo o melato (MO5), de General Carneiro, o de maior teor (117,68± 4,40 mg EAG/g). Para as análises de sequestro das espécies reativas de oxigênio e nitrogênio, os extratos fenólicos foram sempre superiores aos méis brutos in natura. Os extratos fenólicos, de maneira geral, apresentaram alta capacidade de sequestro para o radical peroxila (ROOo), ácido hipocloroso (HOCl) e óxido nítrico (NOo). Em relação aos melatos, o extrato MO7 apresentou alta capacidade para o sequestro do HOCl (EC50= 4,83 ± 0,13 ?g/mL), enquanto que o MO5 foi melhor para o sequestro do NOo (EC50=2,16 ± 0,18 ?g/mL). Pelo método HPLC-ABTS on-line foi possível identificar e quantificar a contribuição para a atividade antioxidante do ácido ferúlico no extrato (MO1) e do flavonoide kanferol na amostra (MO4). O ácido ascórbico foi identificado e quantificado por HPLC somente nos melatos (MO3, MO5 e MO7). Pela técnica de LC-MS/MS foram identificados a presença dos seguintes compostos fenólicos: ácido caféico, rutina e hesperidina em todos os extratos. A análise de compostos voláteis por SPME-CG/EM mostrou a presença de dois compostos, encontrados apenas nos melatos, que foram o terpineno-4-ol, que possui ação antifúngica, antiparasitológica e anti-inflamatória; e o 3,4-dimetil-1-deceno, podendo assim serem utilizados como marcadores químicos destes méis. O conhecimento da composição química destes méis, bem como a composição fenólica bioativa, contribui para o fornecimento de antioxidantes naturais para a dieta, atenuando assim os efeitos negativos dos radicais livres / Brazil has a great potential to explore beekeeping due to its vast territory and diversified flora, what allows different varieties of honeys with unique characteristics. Parana state is one of the largest honey producers and the investment in production that meets the most demanding markets stimulated the organic honey production. The knowledge since early in history regarding the beneficial health effects promoted by honey is stimulating the scientific research of this noble food. Thus, this paper aimed to study certified Brazilian organic honeys (MO) in order to determine the phenolic and volatile profiles, and also the evaluation of radical scavenging capacity against Nitrogen and Oxygen Reactive Species (RNS and ROS, respectively). The honeys were collected from apiaries from beekeepers with the organic certification from two municipalities of southern Parana, General Carneiro and Turvo, PR. In the essays, phenolic extracts were obtained from honeys by using Amberlite® XAD®2 resin, as well as crude in natura honeys. The extracts showed a significant content in phenolic compounds, with honeydew (MO5), from General Carneiro, showing the highest content (117,68 ± 4,40 mg AGE/g). For the analyzes to determine the radical scavenging capacity against RNS and ROS, the phenolic extracts always showed up superior results in comparison to crude in natura honeys. Phenolic extracts showed, in general, great capacity to scavenge peroxyl radical (ROOo), hypochlorous acid (HOCl) and nitric oxide (NOo). In relation to honeydews MO7 extract showed the highest capacity to scavenge HOCl (IC50= 4,83 ± 0,13 ?g/mL) while MO5 was the sample with better capacity to scavenge NOo (IC50=2,16 ± 0,18 ?g/mL). By using HPLC-ABTS on-line method it was possible to identify and to quantify the ferulic acid in MO1 extract, a compound with an important contribution to the antioxidant activity of this sample, as well as the flavonoid kaempferol in MO4 sample. Ascorbic acid was identified and quantified by HPLC only in the honeydew samples (MO3, MO5 and MO7). The analyzes developed by LC-MS/MS techniques indicated the presence of the phenolic compounds caffeic acid, rutin and hesperidin in all the extracts. The analysis of volatile substances developed by SPME-GC/MS promoted the identification of two compounds found only in the honeydew samples. The compounds were the terpinen-4-ol, which has antifungal, antiparasitological and anti-inflammatory activities; and 3,4-dimethyl-1-decene. Both compounds can be used as chemical markers of these honeys. The knowledge of the chemical composition of the studied honeys, as well as their bioactive phenolic composition, contributes to supply natural antioxidants to human diet, thus attenuating the negative effects of free radicals

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

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Aceria guerreronis keifer is one of the main coconut pests in Brazil, its attack causes a premature fall, reduction of fruit size, water weight and volume, as well as stetic esthetic damages (necrosis) depreciating the product. Currently, there are five pesticides registered for the control of the coconut-necrotic mite. However, there is no specificity to A. guerreronis. The Lamiaceae family stands out with some specimens with notable insecticidal activity, among them the Vitex genus, known to have ecdysteroids and iridoids as markers of the genus. However, there is a shortage of specific chemotaxonomic studies for volatile compounds. The objective of this work was to identify the volatile compounds present in the essential oils of the species of Vitex gardneriana Schauer, Vitex capitata Vahl., Vitex rufescens A. Juss., Vitex megapotamica (Spreng.) Moldenk and to evaluate possible effects of toxicity and repellence against A. guerreronis. In addition to analyzing the genetic diversity of species of the genus Vitex using ISSR markers, verifying the occurrence of statistical correlations between the genetic diversity and the chemical profiles of the essential oils. Chromatographic and spectroscopic techniques (GC-MS / FID) were used for the detection of volatile compounds, and the molecular markers of ISSR for the genetic characterization of the species, as well as toxicity and repellency tests against necrotic necrosis. The results showed 46, 45, 41 and 37 constituents for V. capitata, V. megapotamica, V. gardneriana and V. rufences respectively, among which, -copaene, (E)-caryophyllene, -elemene, -humulene, trans-cadine-1(6)4-diene, viridiflorene and -cadinene were the main components of V. capitata and V. megapotamica. 6,9-guaiadiene, caryophyllene oxide, L-calamenene for V. gardneriana and (E)-cariophylene, ledol, germacrene D, -humulene, allo-aromadendrene, viridiflorene and -elemene for V. rufences. The results of molecular markers of ISSR generated a total of 90 fragments, of which 100% were polymorphic. The genotypes of the four Vitex species selected for this study were pooled using the Jaccard coefficient (JC). The mean similarity was 0.21 JC (0.08-0.45 JC). A clear separation of two groups was observed, with V. gardneriana being the most isolated of the four species, and V. capitata and V. megapotamica more closely related to each other. The acaricide activity of the four oils was also evaluated by means of toxicity and repellency tests against A. guerreronis. The essential oil of V. gardneriana showed acaricidal activity against A. guerreronis with a LC50 of 0.85 mg.mL-1, whereas the oils of V. capitata, V. megapotamica and V. rufecens were not toxic to this pest up to 2.3 mg. Ml-1 when tested through the toxicity bioassay. In general, essential oils distilled from the Vitex species repelled A. guerreronis after 24 hours at a concentration of 1.8 mg.mL-1 using abamectin as a control in the two-choice disc repellency assay, however, the essential oil of V. gardneriana presented a statistically significant acaricidal activity against the coconut mite necrosis. Introducing himself as a potential candidate for the development of an acaricide product. / O ácaro-da-necrose-de-coqueiro Aceria guerreronis keifer é uma das principais pragas de coqueiro do Brasil, seu ataque causa queda prematura, redução no tamanho e peso dos frutos e volume de água, além dos danos estéticos (necroses) na casca que diminui o valor comercial do produto. Atualmente, existem cinco agrotóxicos registrados para o controle dessa praga. No entanto, não há especificidade ao A. guerreronis. A família Lamiaceae se destaca com alguns exemplares com notória atividade inseticida, dentre eles, o gênero Vitex, conhecido por possuir dentre seus constituintes os ecdisteroides e iridoides como marcadores do gênero, todavia, há uma escassez de estudo quimiotaxonômicos específicos para compostos voláteis. O objetivo deste trabalho foi identificar os compostos voláteis presentes nos óleos essenciais das espécies de Vitex gardneriana Schauer, Vitex capitata Vahl., Vitex rufescens A. Juss., Vitex megapotamica (Spreng.) Moldenk e avaliar possíveis efeitos de toxicidade e repelência frente ao A. guerreronis, além de analisar a diversidade genética de espécies do gênero Vitex. Técnicas cromatográficas e espectroscópicas (CG-MS/FID) foram utilizadas para detecção dos compostos voláteis, e os marcadores moleculares de ISSR foram empregados para a caracterização genética das espécies, além de testes de toxicidade e repelência contra ao àcaro-da-necrose. Os resultados mostraram 46, 45, 41 e 37 constituintes para V. capitata, V. megapotamica, V. gardneriana e V. rufences respectivamente, dentre os quais, -copaeno, (E)-cariofileno, -elemeno, -humuleno, trans-cadina-1(6),4-dieno, viridiflorene e -cadineno foram os principais componentes de V. capitata e V. megapotamica. 6,9- guaiadieno, óxido de cariofileno, L-calameneno para V. gardneriana e (E)-cariofileno, ledol, germacreno D, -humuleno, allo-aromadendreno, viridifloreno e -elemene para V. rufences. Os resultados dos marcadores moleculares de ISSR geraram um total de 90 fragmentos, dos quais 100% foram polimórficos. Os genótipos das quatro espécies de Vitex selecionadas para este estudo foram agrupados utilizando o coeficiente Jaccard (JC). A média de similaridade foi de 0,21 JC (0,08-0,45 JC). Observou-se uma clara separação de dois grupos, sendo V. gardneriana a mais isolada das quatro espécies, e V. capitata e V. megapotamica mais próxima geneticamente entre si. A atividade acaricida dos quatro óleos também foi avaliada por meio de ensaios de toxicidade e repelência contra o àcaro-da-necrose. O óleo essencial de V. gardneriana mostrou atividade acaricida ao A. guerreronis com uma CL50 de 0,85 mg.mL-1, enquanto que os óleos de V. capitata, V. megapotamica e V. rufecens não foram tóxicos para esta praga até 2,3 mg.ml-1, quando testados através do bioensaio de toxicidade. Em geral, os óleos essenciais destilados a partir das espécies de Vitex repeliram o A. guerreronis após 24 horas a uma concentração de 1.8 mg.mL-1 utilizando abamectina como controle no ensaio de repelência disco de duas escolha, no entanto, o óleo essencial de V. gardneriana apresentou atividade acaricida estatisticamente significativa frente ao ácaro-da-necrose-do-coqueiro. Apresentando-se como potencial candidato para o desenvolvimento de um produto acaricida. / São Cristóvão, SE

O Brasil apresenta grande potencial para a exploração da apicultura, dado ao seu vasto território e flora diversificada, o que permite diferentes variedades de méis com propriedades únicas. O estado do Paraná é um dos maiores produtores de méis do país e o investimento em produção que atenda aos mercados mais exigentes estimulou a produção do mel orgânico. O conhecimento desde a antiguidade sobre os efeitos benéficos à saúde pelo mel vem estimulando a pesquisa deste alimento nobre. Assim, este trabalho teve por objetivo estudar méis orgânicos brasileiros certificados (MO) para a caracterização do perfil fenólico, volátil, além da avaliação da capacidade de sequestro das espécies reativas de oxigênio e nitrogênio. Os méis foram coletados nos apiários de apicultores com certificação orgânica de dois municípios do sul do Paraná, General Carneiro e Turvo-PR. Nos ensaios foram utilizados extratos fenólicos dos méis, obtidos por meio da utilização da resina Amberlite® XAD®2, bem como méis brutos in natura. Os extratos apresentaram conteúdo de compostos fenólicos significativo, sendo o melato (MO5), de General Carneiro, o de maior teor (117,68± 4,40 mg EAG/g). Para as análises de sequestro das espécies reativas de oxigênio e nitrogênio, os extratos fenólicos foram sempre superiores aos méis brutos in natura. Os extratos fenólicos, de maneira geral, apresentaram alta capacidade de sequestro para o radical peroxila (ROOo), ácido hipocloroso (HOCl) e óxido nítrico (NOo). Em relação aos melatos, o extrato MO7 apresentou alta capacidade para o sequestro do HOCl (EC50= 4,83 ± 0,13 ?g/mL), enquanto que o MO5 foi melhor para o sequestro do NOo (EC50=2,16 ± 0,18 ?g/mL). Pelo método HPLC-ABTS on-line foi possível identificar e quantificar a contribuição para a atividade antioxidante do ácido ferúlico no extrato (MO1) e do flavonoide kanferol na amostra (MO4). O ácido ascórbico foi identificado e quantificado por HPLC somente nos melatos (MO3, MO5 e MO7). Pela técnica de LC-MS/MS foram identificados a presença dos seguintes compostos fenólicos: ácido caféico, rutina e hesperidina em todos os extratos. A análise de compostos voláteis por SPME-CG/EM mostrou a presença de dois compostos, encontrados apenas nos melatos, que foram o terpineno-4-ol, que possui ação antifúngica, antiparasitológica e anti-inflamatória; e o 3,4-dimetil-1-deceno, podendo assim serem utilizados como marcadores químicos destes méis. O conhecimento da composição química destes méis, bem como a composição fenólica bioativa, contribui para o fornecimento de antioxidantes naturais para a dieta, atenuando assim os efeitos negativos dos radicais livres / Brazil has a great potential to explore beekeeping due to its vast territory and diversified flora, what allows different varieties of honeys with unique characteristics. Parana state is one of the largest honey producers and the investment in production that meets the most demanding markets stimulated the organic honey production. The knowledge since early in history regarding the beneficial health effects promoted by honey is stimulating the scientific research of this noble food. Thus, this paper aimed to study certified Brazilian organic honeys (MO) in order to determine the phenolic and volatile profiles, and also the evaluation of radical scavenging capacity against Nitrogen and Oxygen Reactive Species (RNS and ROS, respectively). The honeys were collected from apiaries from beekeepers with the organic certification from two municipalities of southern Parana, General Carneiro and Turvo, PR. In the essays, phenolic extracts were obtained from honeys by using Amberlite® XAD®2 resin, as well as crude in natura honeys. The extracts showed a significant content in phenolic compounds, with honeydew (MO5), from General Carneiro, showing the highest content (117,68 ± 4,40 mg AGE/g). For the analyzes to determine the radical scavenging capacity against RNS and ROS, the phenolic extracts always showed up superior results in comparison to crude in natura honeys. Phenolic extracts showed, in general, great capacity to scavenge peroxyl radical (ROOo), hypochlorous acid (HOCl) and nitric oxide (NOo). In relation to honeydews MO7 extract showed the highest capacity to scavenge HOCl (IC50= 4,83 ± 0,13 ?g/mL) while MO5 was the sample with better capacity to scavenge NOo (IC50=2,16 ± 0,18 ?g/mL). By using HPLC-ABTS on-line method it was possible to identify and to quantify the ferulic acid in MO1 extract, a compound with an important contribution to the antioxidant activity of this sample, as well as the flavonoid kaempferol in MO4 sample. Ascorbic acid was identified and quantified by HPLC only in the honeydew samples (MO3, MO5 and MO7). The analyzes developed by LC-MS/MS techniques indicated the presence of the phenolic compounds caffeic acid, rutin and hesperidin in all the extracts. The analysis of volatile substances developed by SPME-GC/MS promoted the identification of two compounds found only in the honeydew samples. The compounds were the terpinen-4-ol, which has antifungal, antiparasitological and anti-inflammatory activities; and 3,4-dimethyl-1-decene. Both compounds can be used as chemical markers of these honeys. The knowledge of the chemical composition of the studied honeys, as well as their bioactive phenolic composition, contributes to supply natural antioxidants to human diet, thus attenuating the negative effects of free radicals

Un grand vin de garde se distingue par sa capacité à se bonifier avec le temps, exprimant alors une complexité aromatique particulièrement attendue par les dégustateurs. L’apparition du bouquet de vieillissement, signature de la qualité organoleptique des grands vins vieillis en bouteille, est un des phénomènes les plus impressionnants de l’œnologie mais également l’un des plus mal connus. En effet, ses déterminants sensoriels et moléculaires ont jusqu’à présent été peu étudiés. Grâce à une approche holistique séquencée en trois étapes, nous avons pu décrypter sensoriellement le concept du bouquet de vieillissement des vins rouges de Bordeaux. Une définition sensorielle partagée par des professionnels du vin a pu émerger, s’articulant autour de huit notes aromatiques principales : « sous-bois », « truffe », « fruits frais rouges et noirs », « épicé », « réglisse », « menthe », « grillé » et « empyreumatique ». D’autre part, nous avons pu souligner l’importance de l’expertise dans la définition d’un tel concept olfactif, nécessitant à la fois des connaissances œnologiques, des compétences sensorielles et des ressources lexicales. Par une étude moléculaire ciblée sur certaines classes de molécules aromatiques se formant et/ou conservées au cours du vieillissement en bouteille, nous avons pu identifier que plusieurs composés soufrés volatils tels le sulfure de diméthyle, le 2-furaneméthanethiol et le 3-sulfanylhexanol contribuaient activement à la typicité du bouquet de vieillissement. Présents à des teneurs significativement plus élevées dans les vins rouges exprimant un bouquet de vieillissement, nous avons montré que ces composés volatils participaient plus particulièrement aux notes aromatiques caractéristiques de sous-bois, truffe et empyreumatique. La mise en œuvre de fractionnements d’extraits de vins et de reconstitutions aromatiques, puis l’application de la GC-O et de la GC-MS sur les fractions d’intérêt ont permis par la suite d’identifier la D,L-pipéritone, un monoterpène associé pour la première fois aux nuances de menthe typiques du bouquet de vieillissement des vins rouges de Bordeaux. Enfin, nous avons montré que certains paramètres du terroir pouvaient influencer l’expression aromatique du bouquet de vieillissement. La mesure du rapport isotopique (δC13) de l’éthanol a permis de retracer l’état hydrique des vignes ayant produit les vins étudiés et a montré qu’une contrainte hydrique modérée ou forte de la vigne était favorable à cette typicité. De plus, la différence sensorielle de la note menthe observée entre les vins rouges de Bordeaux semble trouver son origine dans la nature du cépage, avec des teneurs en D,L-pipéritone significativement plus importantes dans les vins pour lesquels le Cabernet Sauvignon est le cépage prédominant. / A wine with ageing potential is noticeable by its ability to improve over time, expressing the aromatic complexity particularly expected by wine tasters. The development of wine ageing bouquet, the "signature" of the organoleptic quality of fine wines aged in bottle, is one of the most fascinating but least known phenomena in oenology. Indeed, both its sensory and molecular markers are poorly documented.A three-step holistic approach made it possible to decipher the sensory characteristics of the ageing bouquet of red Bordeaux wines. More precisely, a shared sensory definition emerged among wine professionals, structured around eight main aromatic notes: "undergrowth", "truffle", "fresh red- and black berry fruits", "spicy», "liquorice", "mint», "toasted" and "empyreumatic". Furthermore, the importance of expertise based on oenological knowledge, sensory skills, and lexical capabilities in defining olfactory concepts was highlighted. A molecular study, targeting specific classes of aromatic compounds formed and/or preserved during bottle ageing, identified dimethyl sulphide, 2-furanmethanethiol and 3-sulfanylhexanol as key contributors to the typicality of wine ageing bouquet. These volatile compounds were present in the highest concentrations in all wines with an ageing bouquet and participated more specifically in their undergrowth, truffle, and empyreumatic aromas. Subsequently, wine fractionations and aromatic reconstitutions, analyzed by both GC-O and GC-MS, were used to identify D,L-piperitone, a monoterpene which was shown for the first time to be involved in the typical mint nuances in the ageing bouquet of red Bordeaux wines. Finally, influence of some parameters of “terroir” was highlighted. Isotope ratio measurement (δC13) in ethanol of studied wines was used as an indicator of vine water status and revealed that a moderate to severe water deficit was in favor to the genesis of a wine ageing bouquet. Interestingly, the sensory difference in minty character observed in red Bordeaux wines apparently originated from grapes, as D,L-piperitone levels were significantly higher in wines where Cabernet Sauvignon was dominant

This diploma thesis researches coffee authenticity problematice, mainly focusing on the authenticity of geographic origin. In the theoretical part of this work, botanical classification is described as well as production technology and processes. The work also includes chemical composition of coffee, describing the major components and changes during production phases. It describes major production areas of the world, in terms of general description and brief history. Problematics with coffee fraud and its identification are also described. Theoretical part also includes general geological description of 17 studied coffee growing regions. Experimental part is devoted to trace amount analysis of selected elements and volatile compounds. The element analysis was conducted using mass spectrometry or optical emission spectrometry, volatile compounds were determined using gas chromatography combined with mass spectrometry detection. Results were statistically described and analyzed, resulting in several discrimination models based on geographic origin.

The presented dissertation thesis deals with the use of UV-photochemical generation of volatile compounds (UV-PVG) as a derivatization technique for the combination of high-performance liquid chromatography (HPLC) and atomic absorption spectrometry (AAS) detection. Two model elements arsenic and mercury and their compounds were selected for the speciation analysis. The work was divided into several parts that follow. In the first part of the research, the apparatus for the UV-photochemical generation of the volatile mercury compounds and their detection with a new continuum source and high-resolution atomic absorption spectrometer (HR-CS AAS) with an externally heated detection tube was constructed. The analytical method was adapted for use with atomic fluorescence detection with the aim to improve sensitivity of the determination. Furthermore, apparatus for the electrochemical generation of cold mercury vapor with AAS detection was built. The construction of the apparatus was followed by optimization of the reaction conditions (concentration and flow of electrochemical reagents: sulfuric and hydrochloric acid, mobile phase, carrier medium, flow rate of the carrier gas and localization of its introduction), determination of the analytical figures of merit, and comparation of the methods. Both...