Sixty-five samples of propolis were collected from eleven regions of Cuba; methanolic extracts of propolis were prepared from all samples, and a classification method was developed using a combination of NMR, HPLC-PDA, and HPLC-ESI/MS techniques. The analysis of (1)H and (13)C NMR spectra and chromatographic profiles of all propolis extracts allowed the definition of three main types of Cuban propolis directly related to their secondary metabolite classes: brown Cuban propolis (BCP), rich in polyisoprenylated benzophenones, red Cuban propolis (RCP), containing isoflavonoids as the main constituents, and yellow Cuban propolis (YCP), probably with aliphatic compounds. Subsequently, the principal compounds of the brown and red types were characterized by HPLC-ESI/MS analysis. Instrumental techniques used are complementary; NMR was shown to be a quick and informative tool for the rapid analysis of crude propolis polar extracts and allowed the identification of the main class of secondary metabolites, while LC-PDA and LC-MS techniques were useful tools for qualitative and quantitative analysis of marker compounds of Cuban propolis.

Chemical investigation of a red-type Cuban propolis sample has led to the isolation of 11 isoflavonoids (2 isoflavones, 3 isoflavans, and 6 pterocarpans), together with gallic acid, isoliquiritigenin, and (-)-liquiritigenin. Structural determination, including the absolute stereochemistry, was accomplished by spectroscopic analysis, particularly CD and 2D NMR techniques. The fragmentation behavior of pterocarpans was studied by electrospray ionization (ESI) tandem mass spectrometry (MS/MS) using an ion-trap analyzer, and a generalized fragmentation pathway, useful in the identification and structural characterization of pterocarpans, is proposed. Isoflavonoids are reported for the first time from propolis samples.

Chemical investigation of a red-type Mexican propolis sample has led to the isolation of three new compounds, 1-(3',4'-dihydroxy-2'-methoxyphenyl)-3-(phenyl)propane (1), (Z)-1-(2'-methoxy-4',5'-dihydroxyphenyl)-2-(3-phenyl)propene (2) and 3-hydroxy-5,6-dimethoxyflavan (3), together with seven known flavanones, isoflavans, and pterocarpans. Structural determination, was accomplished by spectroscopic analysis, particularly 2D NMR and ESI-MS/MS techniques. The present study appears to be the first report on the occurrence of isoflavonoids in Mexican propolis. In addition, the presence of compounds with a 1,3-diarylpropane and 1,3-diarylpropene carbon skeleton were found for the first time in propolis. Isolated compounds 1-10 indicated the possible relation between red Mexican propolis and the genus Dalbergia.

The molecular signals and pathways that govern biotic and abiotic stress responses in sugarcane are poorly understood. Here we describe SodERF3, a sugarcane (Saccharum officinarum L. cv Ja60-5) cDNA that encodes a 201-amino acid DNA-binding protein that acts as a transcriptional regulator of the ethylene responsive factor (ERF) superfamily. Like other ERF transcription factors, the SodERF3 protein binds to the GCC box, and its deduced amino acid sequence contains an N-terminal putative nuclear localization signal (NLS). In addition, a C-terminal short hydrophobic region that is highly homologous to an ERF-associated amphiphilic repression-like motif, typical for class II ERFs, was found. Northern and Western blot analysis showed that SodERF3 is induced by ethylene. In addition, SodERF3 is induced by ABA, salt stress and wounding. Greenhouse-grown transgenic tobacco plants (Nicotiana tabacum L. cv. SR1) expressing SodERF3 were found to display increased tolerance to drought and osmotic stress.

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Three new polyprenylated benzophenone derivatives, propolones B-D (5-7), together with garcinielliptone I (8) and hyperibone B (9), were isolated from Cuban propolis. All the structures, including relative configurations, were elucidated by spectroscopic methods and computer-generated molecular modeling.

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This is the first pre-clinical report of the anti-inflammatory properties of M. indica extract and mangiferin in experimental asthma and it could be an important part of pre-clinical requirement necessary for its use to complement the treatment of this complex disease.