Wood chemotaxonomy via ESI-MS profiles of phytochemical markers: the challenging case of african versus brazilian mahogany woods

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The harvesting of Brazilian mahogany (Swietenia macrophylla) is a main cause of the Brazilian Amazon deforestation and has been therefore prohibited. African mahogany (Khaya ivorensis) was then introduced for Amazon reforestation and the commercialization of such wood is legal, thus creating a challenging problem for wood certification. Herein we report that a wood chemotaxonomic method based on distinct profiles of phytochemical markers is able to promptly characterize both the native and foreign mahogany species. This challenging task has been performed via a simple, fast and unambiguous methodology using direct electrospray ionization mass spectrometry (ESI-MS) analysis of a simple methanolic extract of a tiny wood chip. Typical limonoids such as khivorin, khayanolide A and mexicanolide for African mahogany and phragmalin-type limonoids for the native Brazilian species, as well as distinct polyphenols such as catechin derivatives and cinchonain, form the characteristic phytochemical marker pools for both species. This rapid methodology could therefore be used to monitor legal and illegal mahogany tree harvesting, and hence to control Amazon deforestation. It could also be applied to create a wood certification program for African and Brazilian mahogany trees, as well as for wood certification in general.The harvesting of Brazilian mahogany (Swietenia macrophylla) is a main cause of the Brazilian Amazon deforestation and has been therefore prohibited. African mahogany (Khaya ivorensis) was then introduced for Amazon reforestation and the commercialization72085768583FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)sem informaçãosem informaçãosem informaçã

Corrole Isomers: Intrinsic Gas-phase Shapes Via Traveling Wave Ion Mobility Mass Spectrometry And Dissociation Chemistries Via Tandem Mass Spectrometry.

Corrole and four of its isomers with subtle structural changes promoted by exchange of nitrogen and carbon atoms in the corrole ring have been studied by traveling wave ion mobility mass spectrometry and collision induced dissociation experiments. Significant differences in shapes and charge distributions for their protonated molecules were found to lead to contrasting gas phase mobilities, most particularly for corrorin, the most confused isomer. Accordingly, corrorin was predicted by B3LYP/6-31g(d,p) and collisional cross section calculations to display the most compact tri-dimensional structure, whereas NCC4 and corrole were found to be the most planar isomers. Better resolution between the corrole isomers was achieved using the more polarizable and massive CO(2) as the drift gas. Sequential losses of HF molecules were found to dominate the dissociation chemistry of the protonated molecules of these corrole isomers, but their unique structures caused contrasting labilities towards CID, whereas NCC4 showed a peculiar and structurally diagnostic loss of NH(3), allowing its prompt differentiation from the other isomers.108396-40

Use of mass spectrometry for the characterization of products linked to biodiversity, green chemistry and sustainability

Orientadores: Marcos Nogueira Eberlin, Alessandra SussuliniTese (doutorado) - Universidade Estadual de Campinas, Instituto de QuímicaResumo: Atualmente, uma das demandas mais urgentes do mundo é a busca pela sustentabilidade dos processos químicos e para a preservação da biodiversidade através, também, da exploração sustentável dos recursos naturais do planeta. Sendo assim, esta tese, dividida em quatro diferentes artigos, demonstrou a aplicação de diversas modalidades de espectrometria de massas para a caracterização de matérias primas ligadas à biodiversidade brasileira (madeiras e óleos nativos provenientes da Amazônia), bem como para a prospecção e certificação de combustíveis feitos de fontes renováveis (oleaginosas e microalgas). No primeiro artigo, foi demonstrado que um método quimiotaxonômico baseado na análise de possíveis marcadores fitoquímicos distintos é capaz de caracterizar e diferenciar amostras de madeira de mogno nativo da Amazônica e de mogno Africano que vem sendo utilizado para reflorestamento de áreas desmatadas. Para isso, utilizou-se uma metodologia simples e rápida através da análise direta por espectrometria de massas e ionização por electrospray (ESI-MS) de um extrato metanólico obtido de um pequeno pedaço de madeira. Limonóides típicos como khivorin, khayanolide A e mexicanolide foram identificados para o mogno Africano; e limonóides do tipo phragmalin, assim como polifenóis distintos como derivados de catequina e cinchonain foram identificados para o mogno nativo Brasileiro, e se destacam como possíveis marcadores fitoquímicos característicos para diferenciar ambas as espécies. Essa metodologia pode, portanto, ser usada como uma ferramenta monitorar o extrativismo ilegal de árvores de mogno e para controlar o desmatamento da Amazônia, assim como pode ser aplicada para criar um programa de certificação de madeiras nativas e de espécies em extinção. O segundo artigo descreveu a otimização de uma metodologia simples para determinar com exatidão os valores de 'sigma'13C em ésteres metílicos de ácidos graxos (FAMEs) da Jatropha curcas (pinhão manso), através da técnica de cromatografia gasosa acoplada à espectrometria de massas de razão isotópica (GC-IRMS). Para isso, foi utilizada uma normalização de dois pontos usando padrões internos e externos para corrigir o fracionamento isotópico oriundo da reação de transesterificação e da análise por GC-IRMS. Observou-se que o processo de transesterificação pode levar a até 2 mUr de desvio dos valores de 'sigma'13C para o padrão interno (FAME C22: 0). Após a normalização de dois pontos, o valor médio de 'sigma'13C determinado para os FAMEs de 9 amostras diferentes de J. curcas foi 'sigma'13CVPDB = -29,51 ± 1,03 mUr, enquanto o valor obtido com a técnica de referência, (EA-IRMS) foi de -28,97 ± 0,43 mUr, que é uma assinatura típica de plantas C3. Este trabalho também demonstrou que procedimentos de qualidade devem ser aplicados para determinações de valores isotópicos exatos e rastreáveis, seguindo o princípio do tratamento idêntico para as amostras e para as referências. Já no terceiro artigo desta tese foram demonstradas estratégias para caracterizar extratos de microalgas utilizando a mobilidade iônica acoplada à espectrometria de massas (TWIM-MS). Primeiramente, os extratos de microalgas foram analisados por infusão direta na fonte ESI, sem prévia separação cromatográfica (DI-ESI-TWIM-MS). A segunda estratégia foi a análise de metabolômica e lipidômica untargeted por cromatografia líquida de ultra-eficiência (UPLC) acoplada a TWIM por análise independente de dados (DIA) - HDMSE como forma de aquisição de MS. Dezesseis biomassas de microalgas foram avaliadas por ambos os métodos. A DI-ESI-TWIM-MS pôde separar diferentes classes de metabólitos, tornando a tipificação de microalgas mais evidente. Já a análise por UPLC-HDMSE, identificou 1251 diferentes metabólitos, detalhando quimicamnete os perfis lipídicos desses extratos de biomassa de microalga. Foi possível discriminar os triacilgliceróis (TAGs) através das determinações das suas seções de choque (CCS), aumentando a confiança em suas identificações. As duas estratégias abordadas se mostraram bastante adequadas para serem aplicadas na indústria de algas, ajudanto a identificar quais são os melhores gêneros e espécies, assim como condições de cultivo, para aplicações específicas de microalgas em biotecnologia. Por fim, o quarto e último artigo desta tese se tratou de um compêndio sobre a composição de óleos de espécies nativas da Amazônia. Foram descritos os perfis de FAMEs e dos TAGs intactos de dezesseis espécies oleaginosas da Amazônia, através da técnica de GC-MS e ESI-MS. Os TAGs foram caracterizados de forma detalhada através de seus espectros de MS/MS, sendo até 40 diferentes TAGs identificados por amostra, somente nos 10 íons mais abundantes. Muitos TAGs isoméricos foram identificados para um mesmo íon precursor, mostrando que a complexidade é muito maior do que previamente relatado na literatura. Manteigas como babaçu, murumuru e manteiga de tucumã apresentaram espectros de massas muito similares entre si, apresentando mínimas variações nas abundâncias relativas de alguns TAGs. Os óleos de patauá e buriti também exibiram perfis de espectros de massas praticamente idênticos. Todas as amostras amazônicas foram comparadas a óleos comerciais como soja, milho, coco e azeite, e seus espectros de massas foram avaliados estatisticamente por meio de análise de componentes principais (PCA). Os resultados mostraram a formação de três grupos principais: manteigas, óleos com alto teor de ácido oleico e óleos com alto teor de ácido linoleico, além de algumas manteigas diferenciadas, como bacuri e cupuaçu, com composições mais próximas dos óleos do que a de outras manteigas. Espera-se que, gerando um maior conhecimento sobre a composição química desses óleos, fique mais fácil detectar possíveis adulterações em produtos que os empregam em sua composição. Além disso, incentiva-se a produção sustentável e o uso adequado dos recursos florestais Amazônicos, podendo até mesmo servir como base para a criação de um selo de certificação de origem. Através de todas as diferentes aplicações apresentadas nesta tese, almeja-se contribuir com ferramentas analíticas para a proteção de espécies nativas brasileiras, bem como auxiliar nas pesquisas para o uso adequado dos seus recursos naturais do planetaAbstract: One of the most urgent demands in the world nowadays is the search for sustainability of the chemical processes and for the exploitation of natural resources of the planet. Thus, this thesis, divided in four different articles, aimed to demonstrate the application of several mass spectrometry (MS) modalities for the characterization of raw materials from Brazilian biodiversity (native woods and Amazonian oils), as well as for prospecting and certification of biofuels made from renewable sources (oilseeds and microalgae). In the first article, it is demonstrated that a wood chemotaxonomic method based on distinct profiles of phytochemical markers is able to promptly characterize both the Amazonian native and foreign mahogany species. This challenging task has been performed via a simple, fast and unambiguous methodology using direct electrospray ionization mass spectrometry (ESI-MS) analysis of a simple methanolic extract of a tiny wood chip. Typical limonoids such as khivorin, khayanolide A and mexicanolide for African mahogany and phragmalin-type limonoids for the native Brazilian species, as well as distinct polyphenols such as catechin derivatives and cinchonain, form the characteristic phytochemical marker pools for both species. This rapid methodology could therefore be used to monitor legal and illegal mahogany tree harvesting, and hence to control Amazon deforestation. It could also be applied to create a wood certification program for African and Brazilian mahogany trees, as well as for wood certification in general. The second article described the optimization of a simple methodology to accurately determine the 'sigma'13C values in Jatropha curcas FAMEs as a test case, by a two-point normalization using internal and external standards to correct the isotopic fractionation from the transesterification reaction and from the GC-IRMS analysis itself. We observed that the transesterification process may lead up to 2 mUr of deviation of 'sigma'13C values for the internal standard (FAME C22:0). After the two point normalization, the determined 'sigma'13C average value for the FAMEs of 9 different samples of J. curcas was 'sigma'13CVPDB = -29.51 ± 1.03 mUr, while the bulk value obtained with EA-IRMS was -28.97 ± 0.43 mUr, a typical signature of C3-plants. This work also demonstrates that major quality procedures must indeed be applied for accurate determinations of isotopic values, especially in GC analysis, following the identical treatment principle. In the third article, were reported strategies to characterize microalgae extracts via traveling wave ion mobility ¿ mass spectrometry (TWIM-MS). First, we analyzed microalgae extracts by direct infusion to an electrospray ion source (ESI) with no previous chromatographic separation (DI-ESI-TWIM-MS). Second, we screened metabolites and lipids in the extracts via an untargeted high throughput method by ultra-performance liquid chromatography (UPLC) coupled to TWIM using data independent analysis (DIA) ¿ MSE (UPLC-HDMSE). Sixteen different microalgae biomasses were evaluated by both approaches. DI-ESI-TWIM-MS was able, via distinct drift times, to set apart different classes of metabolites, making microalgae typification more evident. UPLC-HDMSE, identified 1251 different metabolites, providing their lipid profiles, serving, therefore, as a powerful tool to determine best biotechnological applications for algae samples. Collision-cross section determinations was able to discriminate triacylglycerols (TAGs), increasing the confidence in their identifications, serving, therefore, as a guide for biofuels production. These two approaches seem to offer powerful tools for the algae industry identifying ideal strains and culture conditions for specific biotechnology applications, saving time in the analysis, and providing a wider number of identified species. The fourth and last article in this thesis was about a compendium on Amazonian oils composition, in which a detailed fatty acids and intact TAGs of sixteen different oleaginous Amazonian species was reported, by using gas chromatography-mass spectrometry and electrospray high-resolution mass spectrometry. The TAGs were characterized by their MS/MS spectrum resulting in a detailed study about TAGs composition in these samples. Over 40 different TAGs were identified and the occurrence of isomers was remarkable, showing that TAGs complexity in these samples is much higher than reported in some previous literature about Amazonian oils composition. For samples such as babassu, murumuru and tucuma butter, the mass spectra were almost identical, presenting only minimal variations in some TAGs relative abundances. Patawa and buriti oils also displayed identical mass spectra profiles. All the Amazonian samples were compared to trivial oils such as soybean, corn, coconut and olive oil, and their mass spectra were statistically evaluated using principal component analysis (PCA). The results showed a formation of three main groups: butters, high oleic acid oils and high linoleic acids oils, plus some disconnected butters such as bacuri and cupuaçu with compositions closer to oils than to other butters. Generating a greater knowledge about the chemical composition of these oils, it is easier to detect possible adulterations in products that employ them in their composition, and additionally, encourage the sustainable production and appropriate use of Amazon forest resources, or the creation of certification of origin stamp. From the applications presented in this thesis, we are expecting to contribute with analytical tools for the protection of Brazilian native species, as well as to help the researches that leads to the proper use of planet¿s natural resourcesDoutoradoQuimica AnaliticaDoutora em Ciência

Applications of ion mobility mass spectrometry as an analytical technique for the study of complex mixtures and isomers separations

Orientador: Marcos Nogueira EberlinDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de QuímicaResumo: Esta dissertação apresenta uma breve introdução sobre a técnica de mobilidade iônica acoplada a espectrometria de massas (Capítulo 1) e a discussão de resultados aplicados a três subprojetos distintos. A técnica de TWIM-MS é uma técnica de separação na qual a separação em dos íons ocorre em uma cela de mobilidade iônica e é baseada em parâmetros como a seção de choque, carga, polarizabilidade, que é a capacidade de um íon ter sua densidade eletrônica distorcida pela interação com o gás de mobilidade, além de, obviamente, da estrutura tridimensional dos íons em fase gasosa. Sobre o Capitulo 2, objetivo do trabalho em petroleômica foi desenvolver e otimizar um método para a identificação de compostos polares presentes em amostras de petróleo e seus derivados como diesel e gasolina, que fosse capaz de diferenciar amostras distintas com relação essas composições, verificando quais respostas esta técnica pode fornecer nos estudos petroleômicos. Puderam ser identificadas as classes N, O2 e NO, com excelente resolução com a técnica de TWIM-MS. Entretanto, acredita-se que algumas outras classes ainda podem ser elucidadas. O CO2 se mostrou ser o melhor gás de mobilidade a ser utilizado para a resolução destas classes. A técnica de TWIM-MS também se mostrou adequada para a caracterização de gasolina e seus aditivos, entretanto mais amostras de diesel aditivado devem ser investigadas, para se descobrir porque os aditivos não puderam ser detectados através da técnica de ESI-TWIM-MS. Com relação ao estudo das estruturas em fase gasosa dos isômeros do Corrol (Capítulo 3), podese observar que o corrorin tem a estrutura tridimensional mais compacta entre todos os isômeros, enquanto NCC4 e corrol são os isômeros com maiores seções de choque e maiores drift times. Mesmo que o norrole tenha os maiores valores previstos de CCS, seu menor momento de dipolo resulta em interações mais fracas com o gás de mobilidade, e um drift time menor do que o esperado é obtido. Uma melhor resolução entre os isômeros de corrol foi alcançada usando CO2 como gás de mobilidade. Além disso, estes isômeros podem ser diferenciados monitorando íons característicos resultantes de suas fragmentações. Em conclusão, mostrou-se que a diferenciação por TWIM-MS destas estruturas pode ser conseguida através do monitoramento das diferenças entre as suas mobilidades relativas e também pelos espectros distintos de MS/MS obtidos para cada isômero. Já o Capítulo 4, visou avaliar a separação de 4 dissacarídeos isoméricos, em que se observou que a utilização de mais gases polarizáveis, tais como o CO2 na análise realizada com o Synapt G2 permite uma resolução quase na linha de base, o que não foi possível utilizando N2 como gás de mobilidade e nem na primeira geração do equipamento comercial Synapt, mesmo usando CO2 como gás de mobilidadeAbstract: This dissertation presents a brief introduction of the technique of Ion Mobility Mass Spectrometry (Chapter 1) and also the discussion of results applied to three distinct subprojects. The technique of Traveling Wave Ion Mobility Mass Spectrometry, is a separation technique in which the separation of the ions occurs in a mobility cell and is based on parameters such as collision cross-section, charge, polarizability (the capacity of an ion to have its electronic density distorted by interaction with the drift gas) and the three dimensional structure (shape) of ions in the gaseous phase. The main goal of the work performed in petroleomics (Chapter 2), was to develop and optimize a method for the identification of polar compounds present in oil samples and its derivatives, such as diesel and gasoline. The applied method was able to differentiate oil samples based on some polar components. Classes N, O2 and NO could be identified with proper resolution with TWIM-MS technique. However, it is believed that some other classes may be elucidated. CO2 was shown to be the best drift gas to be used for the separation of these classes. The technique of TWIM-MS also proved to be suitable for the characterization of gasoline and its additives, however, more samples of additive diesel must be investigated to find out why the additives could not be detected by the technique of ESI-TWIM-MS. During the study of tridimensional structures in the gaseous phase of five Corrole isomers (Chapter 3), it was observed that significant differences in shape and charge distributions for the protonated molecules lead to contrasting gas phase mobilities, most particularly for corroin, the most "confused¿ isomer. Accordingly, corroin was predicted by DFT and collisional cross section calculations to display the most compact tridimensional structure. NCC4 and corrole, on the other hand were found to be the most planar isomers. Better resolution between the corrole isomers was achieved using the more polarizable and massive CO2 as the drift gas and contrasting labilities towards CID, allowed the prompt differentiation of some isomers. Chapter 4 aimed to evaluate the separation of four isomeric disaccharides, where it was observed that the use of more polarizable gases, such as CO2, in the analysis performed with a Synapt G2 allows almost a baseline resolution for some isomeric pairs. This was not possible using N2 as drift gas with the Synapt G2, and not with the Synapt G1 using either N2 or CO2MestradoQuimica AnaliticaMestra em Químic

Analysis of 31 Hydrazones of Carbonyl Compounds by RRLC-UV and RRLC-MS(/MS): A Comparison of Methods

Aldehydes and ketones are volatile organic compounds (VOC) emitted into the atmosphere by a large number of natural and anthropogenic sources. Carbonyl compounds (CC) are atmospheric pollutants with known damaging effects for the human’s health. In this work, the separation of 31 carbonyl compounds (CC) in their 2,4-dinitrophenylhydrazones form was optimized by rapid resolution liquid chromatography in 9 minutes and simultaneously detected by ultraviolet and mass spectrometry with an APCI(−) as ionization source. The mass spectra of hydrazones presented the [M-H]− ions as base peak, but the MS/MS spectra showed fragments related to different structural classes of aldehydes and ketones, representing an important tool to assist structure elucidation of unknown CC in real samples. Multiple reactions monitoring (MRM) improved the sensitivity and selectivity for the quantitation method. Analytical parameters using both UV and MS (linearity, determination coefficients, detection limits, and sensitivity) were compared. The detection methods are complementary and a powerful analytical tool for the detection and quantitation of CC in complex environmental samples

Chemical Composition of Pyroligneous Acid Obtained from Eucalyptus GG100 Clone

The present study aimed to characterize the chemical composition of pyroligneous acid (PA) obtained from slow pyrolysis of the clone GG100 of Eucalyptus urophylla × Eucalyptus grandis. The efficiency of extraction of organic compounds by using different solvents—dichloromethane (DCM), diethyl ether (DE) and ethyl acetate (EA)—was evaluated. Wood discs were collected and carbonized at a heating rate of 1.25 °C/min until 450 °C. Pyrolysis gases were trapped and condensed, yielding a crude liquid product (CLP), which was refined to obtain pure PA. Then liquid–liquid extraction was carried out. Each extracted fraction was analyzed by GC-MS and the chemical compounds were identified. Experimental results showed that a larger number of chemical compounds could be extracted by using DCM and EA in comparison to diethyl ether DE. A total number of 93 compounds were identified, with phenolic compounds being the major group, followed by aldehydes and ketones, furans, pyrans and esters. Higher contents of guaiacol, phenol, cresols and furfural seem to explain the antibacterial and antifungal activity shown by PA, as reported previously in the literature. Experimental data indicated that the organic phase extracted from GG100 PA consists of a mixture of compounds similar to liquid smokes regularly used in the food industry

Structural organization and supramolecular interactions of the task-specific ionic liquid 1-methyl-3-carboxymethylimidazolium chloride: solid, solution, and gas phase structures

Using a set of different techniques, which included single crystal X-ray, NMR, UV-vis, conductivity measurements, SAXS (small angle X-rays), ESI-MS(/MS) (electrospray (tandem) mass spectrometry), and theoretical calculations, an ample study of the structural organization and supramolecular interaction of the task-specific ionic liquid 1-methyl-3-carboxymethylimidazolium chloride (named MAI.Cl) was conducted. All techniques allowed for comprehensive investigation in the solid state, solution, and gas-phase behavior of MAI.Cl. Most relevant interactions are demonstrated showing the importance of hydrogen bonding to supramolecular organization of MAI.Cl in different states and its tendency to aggregate in aqueous solutions. © 2014 American Chemical Society.Using a set of different techniques, which included single crystal X-ray, NMR, UV–vis, conductivity measurements, SAXS (small angle X-rays), ESI-MS(/MS) (electrospray (tandem) mass spectrometry), and theoretical calculations, an ample study of the structu118311787817889CAPES - COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIORCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFINEP - FINANCIADORA DE ESTUDOS E PROJETOSFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOFsem informaçãosem informaçãosem informaçãosem informaçãosem informaçãoHallett, J.P., Welton, T., Room-Temperature Ionic Liquids: Solvents for Synthesis and Catalysis. 2 (2011) Chem. 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