Estudo da formação, estabilidade e reatividade de ions na fase gasosa atraves de espectrometria de massas pentaquadrupolar e calculos teoricos de orbitais moleculares

Orientador: Marcos Nogueira EberlinDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de QuimicaMestrad

Sintese, estrutura, reatividade e propriedades de ions convencionais, distonicos e não-classicos na fase gasosa : aplicações da espectrometria de massa pentaquadrupolar

Orientador : Marcos N. EberlinTese (doutorado) - Universidade Estadual de Campinas, Instituto de QuimicaDoutorad

Simultaneous Extraction And Analysis By High Performance Liquid Chromatography Coupled To Diode Array And Mass Spectrometric Detectors Of Bixin And Phenolic Compounds From Annatto Seeds.

This study was designed to identify and quantify the carotenoids and phenolic compounds from annatto seeds using high performance liquid chromatography coupled to diode array and mass spectrometer detectors (HPLC-DAD-MS/MS). Furthermore, using response surface methodology, an optimized procedure for simultaneous extraction of these compounds was established. In addition to bixin, known to be the main carotenoid in annatto seeds, hypolaetin and a caffeoyl acid derivative were identified as the main phenolic compounds. The optimized procedure involved 15 extractions using acetone:methanol:water (50:40:10, v/v/v) as solvent, a solid-liquid ratio of 1:9 (m/v) and an extraction time of 5 min. Validation data indicated that the HPLC method proposed provided good linearity, sensitivity, procedure accuracy, system precision and suggested its suitability for the simultaneous analysis of phenolic compounds and carotenoids in annatto seeds.121857-6

Cloud point method applied to the Apolipoprotein A-I extraction from human plasma and its identification by tandem mass spectrometry

This work describes the extraction of the apolipoprotein A-I (apoA-I) from human plasma using the cloud point extraction (CPE). The CPE was carried out with a nonionic surfactant (5 % w/v Triton® X-114), and the presence of a salting-out effect (10 % w/v NaCl) promoted biocompatible separation conditions at room temperature and pH 6.8. The apoA-I present in the surfactant-rich phase was identified by tandem mass spectrometry after two-dimensional gel electrophoresis

N-glycan utilization by bifidobacterium gut symbionts involves a specialist β-Mannosidase

Bifidobacteria represent one of the first colonizers of human gut microbiota, providing to this ecosystem better health and nutrition. To maintain a mutualistic relationship, they have enzymes to degrade and use complex carbohydrates non-digestible by their hosts. To succeed in the densely populated gut environment, they evolved molecular strategies that remain poorly understood. Herein, we report a novel mechanism found in probiotic Bifidobacteria for the depolymerization of the ubiquitous 2-acetamido-2-deoxy-4-O-(β-d-mannopyranosyl)-d-glucopyranose (Man-β-1,4-GlcNAc), a disaccharide that composes the universal core of eukaryotic N-glycans. In contrast to Bacteroidetes, these Bifidobacteria have a specialist and strain-specific β-mannosidase that contains three distinctive structural elements conferring high selectivity for Man-β-1,4-GlcNAc: a lid that undergoes conformational changes upon substrate binding, a tryptophan residue swapped between the two dimeric subunits to accommodate the GlcNAc moiety, and a Rossmann fold subdomain strategically located near to the active site pocket. These key structural elements for Man-β-1,4-GlcNAc specificity are highly conserved in Bifidobacterium species adapted to the gut of a wide range of social animals, including bee, pig, rabbit, and human. Together, our findings uncover an unprecedented molecular strategy employed by Bifidobacteria to selectively uptake carbohydrates from N-glycans in social hosts4314732747FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2015/26982-0; 2016/00740-2We would like to thank Brazilian Synchrotron Light Laboratory (LNLS) and Brazilian Biosciences National Laboratory (LNBio) for the provision of time on the MX2 and SAXS1 beamlines, and ROBOLAB facility. We thank Esther Lorizolla Cordeiro for providing illustrations for figure preparation. This work was supported by Grant No. 2015/26982-0 from São Paulo Research Foundation (FAPESP) (to M.T.M.). RLC was supported by FAPESP Grant No. 2016/00740-

Evaluation Of Proteome Alterations Induced By Cadmium Stress In Sunflower (helianthus Annuus L.) Cultures.

The present study evaluates, at a proteomic level, changes in protein abundance in sunflower leaves in the absence or presence (at 50 or 700mg) of cadmium (as CdCl2). At the end of the cultivation period (45 days), proteins are extracted from leaves with phenol, separated by two-dimensional difference gel electrophoresis (2-D DIGE), and excised from the gels. The differential protein abundances (for proteins differing by more than 1.8 fold, which corresponds to 90% variation) are characterized using nESI-LC-MS/MS. The protein content decreases by approximately 41% in plants treated with 700mg Cd compared with control plants. By comparing all groups of plants evaluated in this study (Control vs. Cd-lower, Control vs. Cd-higher and Cd-lower vs. Cd-higher), 39 proteins are found differential and 18 accurately identified; the control vs. Cd-higher treatment is that presenting the most differential proteins. From identified proteins, those involved in energy and disease/defense (including stress), are the ribulose bisphosphate carboxylase large chain, transketolase, and heat shock proteins are the most differential abundant proteins. Thus, at the present study, photosynthesis is the main process affected by Cd in sunflowers, although these plants are highly tolerant to Cd.119170-17

A binuclear silver complex with L-buthionine sulfoximine: synthesis, spectroscopic characterization, DFT studies and antibacterial assays{

A binuclear silver(I) complex with the amino acid L-buthionine sulfoximine (BSO) of composition Ag 2 C 8 H 16 N 2 O 3 S was synthesized and characterized by chemical and spectroscopic measurements, and DFT (density functional theory) studies. Solid-state 13 C nuclear magnetic resonance (SSNMR) and infrared vibrational spectroscopy (IR) analyses indicate the coordination of the nitrogen and carboxylate groups of the amino acid moiety to one of the silver atoms, while coordination to the second silver atom occurs through the nitrogen of the sulfoximine group. ESI-QTOF-MS measurements show the maintenance of the binuclear structure in solution. DFT studies confirm the proposed structure as a minimum of the potential energy surfac