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Chemical analysis of Brasilimeria Stach, 1949 (Hexapoda, Collembola, Neanuridae) hemolymphatic secretion, and description of a new species

Norberto P. Lopes 1 Francisco J. B. Mendonc? a-Junior 1 0 Laborato ?rio de Sistema ?tica de Colembolla e Conservac ?a?o, Department of Biological Sciences, State University of Para ??ba , Joa?o Pessoa-PB ... . Author Contributions Conceptualization: Douglas Zeppelini, Norberto P. Lopes. Formal analysis: Douglas Zeppelini, Gabriel C. Queiroz, Francisco J. B. Mendonc?a-Junior. Methodology: Norberto P. Lopes

Aplicação da química quântica computacional no estudo de processos químicos envolvidos em espectrometria de massas

The field of application of mass spectrometry (MS) has increased considerably due to the development of ionization techniques. Other factors that have stimulated the use of MS are the tandem mass spectrometry (MS/MS) and sequential mass spectrometry (MSn) techniques. However, the interpretation of the MS/MS and MSn data may lead to speculative conclusions. Thus, various quantum...

Differential metabolic and biological profiles of Lychnophora ericoides mart. (Asteraceae) from different localities in the Brazilian "campos rupestres

Gerais State were collected in March 1998, by Leonardo Gobbo Neto and Norberto P. Lopes at: Ibiraci (NPL284; S 20°20'046', W 047°08'229''; 1090 m altitude), Delfinópolis (NPL123; S 20°20'550'', W 046

Metabolic profile and safety of piperlongumine

Fernanda de Lima Moreira Maísa D. Habenschus Thiago Barth Lucas M. M. Marques Alan Cesar Pilon Vanderlan da Silva Bolzani Ricardo Vessecchi Norberto P. Lopes Anderson R. M. de Oliveira OPEN Piperlongumine

Characterisation of Flavonoid Aglycones by Negative Ion Chip-Based Nanospray Tandem Mass Spectrometry

November 2011 Academic Editor: Michael Niehues Copyright © 2012 Paul J. Gates and Norberto P. Lopes. This is an open access article distributed under the Creative Commons Attribution License, which

Fundamentals and Applications of Analytical Chemistry in Natural Products

2012 Copyright © 2012 Norberto P. Lopes et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and ... flavonoids were readily identified. Norberto P. Lopes Ernani Pinto Michael Niehues Paul J. Gates Ricardo Vessecchi

Tannins Possessing Bacteriostatic Effect Impair Pseudomonas aeruginosa Adhesion and Biofilm Formation

Plants produce many compounds that are biologically active, either as part of their normal program of growth and development or in response to pathogen attack or stress. Traditionally, Anadenanthera colubrina, Commiphora leptophloeos and Myracrodruon urundeuva have been used by communities in the Brazilian Caatinga to treat several infectious diseases. The ability to impair...

Clusiaxanthone and tocotrienol Series from Clusia pernambucensis and their antileishmanial activity

Phytochemical analysis of the ethyl acetate extract from the stem bark of Clusia pernambucensis G. Mariz, Clusiaceae, a Brazilian Cerrado species, led to the isolation and full characterization of a new xanthone, 1,7-dihydroxy-2-(3-methyl-2-butenyl)-6',6'-dimethylpyrano(2',3':3,4)xanthone, namely clusiaxanthone. Four previously unreported tocotrienols from this species were also...

Fragmentation studies on tetronasin by accurate-mass electrospray tandem mass spectrometry

We report here the first full fragmentation study of tetronasin 1. Fragmentation was carried out by high-resolution ESI-CID-MSn. The formulae of the fragment ions were determined by accurate mass measurements. It is demonstrated that the fragmentation routes observed derive essentially from a first loss of water via two different mechanisms. One minor route consists of a charge...

Variabilidade sazonal do teor de saponinas de Baccharis trimera (Less.) DC (Carqueja) e isolamento de flavona

The aim of this study was to evaluate the seasonal effect on the foam index and the isolation and structural identification of a chemical constituent (flavone) of Baccharis trimera. The culture staminate samples of B. trimera were realized in the experimental cultivation area of the Universidade de Ribeirão Preto - Unaerp, in Ribeirão Preto, state of São Paulo, Brazil from...