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Metabolic profiling of complex biological matrices based on liquid chromatography-mass spectrometry (LC-MS) allows detecting a wide range of metabolites with distinct concentrations and physicochemical properties. Given the complexity of samples and the necessity of a comprehensive approach in untargeted metabolomics, quality control strategies are mandatory to obtain high-quality data. The LC-MS performance must be monitored and evaluated to guarantee data reliability. In this study, a test mixture (TM) was developed, systematically evaluated, and applied to untargeted metabolomics of urine samples from individuals suspected of inborn errors of metabolism. The TM was composed of fifteen analytes that eluted across the entire gradient in reversed-phase columns and ionized in positive/negative electrospray modes. It helped set the LC-MS conditions for urine analysis, from sample reconstitution solvent to selecting the MS ion source parameters. The TM quickly indicated column stationary phase degradation during the batch analysis when employed to monitor and evaluate the LC-MS system in an untargeted metabolomic analysis. Thus, in addition to pooled QC samples, a TM can be employed in untargeted metabolomics to rapidly assess the system performance avoiding unnecessary efforts for further data treatment and multivariate analysis of poor-quality data

Soy production in Brazil is an important factor for the agro-industrial, economic, and social development of the country. The expansion of soy in the Brazilian territory is mainly due to the incorporation of new genetic characteristics into cultivars that granted resistance to the Cerrado conditions and to herbicides. Currently, Brazilian soy production is the result of genetically modified cultivars. Studies regarding the chemical composition of soybeans show that qualitative and quantitative variations can occur, depending on the region of production. This work aimed to investigate the chemical composition of soybeans produced in different cities of the Triângulo Mineiro region/MG, Brazil (Harvest 2017/2018) and stored in three warehouses located in the city of Uberaba/MG. The grain analysis was made by liquid chromatography coupled to electrospray ionization mass spectrometry (LC-MS-ESI). The classes of metabolites identified from methanolic extraction were organic acids, phenolic compounds, flavonoids, sugars, amino acids, dipeptides, nitrogenous bases, nucleosides, sphingolipids, and fatty acids. The isoflavones genistein, daidzein, glycitein, genistin, acetyldaidzin, and acetylgenistin were identified in soybeans from the three warehouses. The flavonoid eriodictyol-O-hexoside was also found. The Principal Component Analysis (PCA) from the mass spectrum data obtained by direct injection in the negative and positive modes evidenced the well-defined separation of three groups, indicating that there was variance among the soy samples from each warehouse. The samples from warehouses 1 and 3 showed greater similarity in the Hierarchical Cluster Analysis (HCA) in negative mode, while in positive mode, the samples from warehouses 2 and 3 presented greater similarity.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Reações de acoplamento Carbono-Carbono (C-C), catalisadas por paládio, estão entre as metodologias sintéticas mais importantes e usadas para a construção de estruturas moleculares orgânicas. A importância e relevância dessas metodologias foi reconhecida pela atribuição do prêmio Nobel de Química de 2010, aos pesquisadores, Heck, Negishi e Suzuki, que muito contribuíram nessa área. Estas reações normalmente são realizadas em solventes orgânicos anidros, alguns tóxicos, inflamáveis e caros. Na contramão dessas condições, tem surgido muitas alternativas, ambientalmente corretas, utilizando meios atóxicos e baratos como a água, dentro dos preceitos da Química Verde. O uso da água como solvente em reações catalisadas por paládio, para o acoplamento C-C, talvez seja umas das mais bem-vindas metodologias catalíticas em síntese orgânica, aliando eficiência, consciência ambiental e custo reduzido. Neste trabalho foram sintetizados catorze aldeídos iônicos, sendo dois com grupos de caráter aniônico (sulfonato e ácido carboxílico) e doze com grupos catiônicos, sendo seis com sítio imidazólio e seis com o sítio trifenilfosfônio, com rendimentos entre 65% e 99%. Obtido os aldeídos, estes foram submetidos a reação de condensação com a o-fenilenodiamina, obtendo-se catorze iminas com rendimentos entre 65 e 95%. Essas iminas foram utilizadas como ligantes para a obtenção de complexos iônicos de paládio(II), utilizando acetato de paládio(II) como fonte de paládio, com rendimentos que variaram entre 67% e 92%. Feita a síntese desses complexos, a próxima etapa foi a avaliação dos mesmos como catalisadores do acoplamento de Heck utilizando água como solvente. Inicialmente parâmetros como natureza da base, tipo de surfactante, temperatura e tempo de reação foram avaliados com o intuito de estabelecer a melhor condição reacional para a reação de Heck em água utilizando o bromobenzeno e estireno como substratos. Feito isso, os complexos sintetizados foram aplicados como catalisadores na reação de acoplamento e todos os complexos apresentaram uma atividade catalítica satisfatória com rendimentos variando de 54 a 100% na obtenção do produto de acoplamento. Quatro complexos de paládio(II) das bis-aminas iônicas, análogos reduzidos das bis-iminas iônicas foram obtidos com rendimentos entre 73 e 85%. Os testes de catálise do acoplamento de Heck com esses complexos como catalisadores forneceram rendimentos entre 48 e 85%, resultados próximos aos obtidos utilizando os análogos das bis-iminas. Carbon-Carbon coupling reactions catalyzed by palladium are among the most important and used synthetic methodologies for the construction of organic molecular structures. The importance and relevance of these methodologies was recognized by the award of the 2010 Nobel Prize in Chemistry to the researchers, Heck, Negishi and Suzuki, who contributed greatly in this area. These reactions are usually carried out in anhydrous organic solvents, some of which are toxic, flammable and expensive. Contrary to these conditions, many alternatives have emerged, environmentally correct, using non-toxic and cheap means such as water, within the precepts of Green Chemistry. The use of water as a solvent in palladium-catalyzed reactions for C-C coupling is perhaps one of the most welcome catalytic methodologies in organic synthesis, combining efficiency, environmental awareness and reduced cost. In this work, fourteen ionic aldehydes were synthesized, two of them with anionic groups (sulfonate and carboxylic acid) and twelve with cationic groups, six with imidazolium site and six with triphenylphosphonium site, with yields between 65 and 99%. Once the aldehydes were obtained, they were subjected to a condensation reaction with o-phenylenediamine, obtaining fourteen imines with yields between 65 and 95%. These imines, in turn, were used as binders to obtain ionic palladium(II) complexes, using palladium(II) acetate as palladium source, with yields ranging between 67 and 92%. The obtained palladium(II) complexes were used as catalysts in Heck coupling, using water as solvent. Initially parameters such as base, surfactant, temperature and time were evaluated in order to establish the best reaction condition for the Heck reaction in water using bromobenzene and styrene as substrate. After that, the synthesized complexes were applied as catalysts in the coupling reaction and all the complexes showed a satisfactory catalytic activity of 54 to 100% of yield in obtaining the coupling product. Four palladium(II) complexes of ionic bis-amines, reduced analogues of ionic bis-imines were obtained with yield between 73 and 85%. Heck coupling catalysis tests with these complexes as catalysts provided yields between 48 and 85%, results close to those obtained using the bis-imine analogues.