Novel Cytotoxic 4-Phenylfuranocoumarins from Calophyllum dispar

Eight new 4-phenylfuranocoumarins (1−8) have been isolated from the stem bark and the fruits of Calophyllum dispar, together with three known coumarins. The structures of 1−8 were established by means of spectroscopic analysis, including extensive 2D NMR studies. Some of these furanocoumarins exhibited significant cytotoxic activity against KB cells

Évolution de la concentration en protozoaires et en ammoniaque de fermentations ruminales avec un substrat supplémenté en extraits de plantes à saponines

Yucca schidigera et Quillaja saponaria sont des plantes à saponines (PAS) utilisées en alimentation des ruminants pour optimiser la gestion de l’ammoniaque (NH3) dans le rumen, en particulier lorsque les rations sont riches en azote soluble (e.g. mise à l’herbe, manque d’énergie). Les données sur d’autres PAS sont rares bien que ces métabolites secondaires amphiphiles sont présentes dans beaucoup de végétaux. L’objectif de ce travail était de déterminer in vitro l’effet d’extraits de plantes à saponines sur l’évolution du nombre de protozoaires et sur la concentration en NH3 du fluide ruminal

Matrix for specific detection of alkaloids by MALDI-​TOF mass spectrometry

The présent invention relates to a novel bithiophenic matrix for spécifie détection of alkaloids by MALDI-TOF mass spectrometr

Caractérisation d’extraits de plantes à saponines par analyse chimique (HPLC-MSn) et activité hémolytique

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Potential of extracts from Saponaria officinalis and Calendula officinalis to modulate in vitro rumen fermentation with respect to their content in saponins

Saponins have the potential to favorably modulate rumen fermentation, but there is generally a lack of the chemical structures associated with the described effects. The activity of extracts from Calendula officinalisand Saponaria officinalis in the rumen was evaluated in vitro. The S. officinalis root extract, reduced CH4production by 8.5% and increased total VFA concentration by 25.2%. C. officinalis and S. officinalis root extracts and the S. officinalis aerial part extract decreased the acetate to propionate ratio from 8.6 to 17.4%, according to the extract. An HPLC-ELSD analysis indicated that the saponin content ranged from 43.6 to 57.6 mg/g of dry matter (DM) in the C. officinalis extracts and from 224.0 to 693.8 mg/g of DM in the S. officinalis extracts, expressed as the hederacoside C equivalent. Identification of the saponin compounds present in the extracts by HPLC–MSn suggested that the saponin profile modulated the biological activities, showing the importance of determining the structure of saponins when evaluating extracts

Identification of coumarins in DCM bark, leaf and fruit extracts from Mammea neurophylla (Calophyllaceae) by LC-PDA-MSn

4-phenyl and 4-propylcoumarins display a wide variety of biological activities including anti-oxidant and anti-inflammatory effects, antiparasitical activities against Leishmania or Plasmodium as well as antibacterial, antiviral (HIV) and cytotoxic activities. Using LC-PDA-MSn we have developed a specific protocol allowing the simultaneous and qualitative detection of 4-phenyl and 4-propylcoumarins in DCM bark, fruit and leaf extracts obtained from Mammea neurophylla. By comparison of their retention times, MS and UV data with that of authentic samples, nine, seven and five 4-phenylcoumarins could be directly identified in bark, leaf and fruit extracts respectively. On the other hand, interlocking UV spectra and ESI-MSn data analysis allowed us to deduce plausible structures of five, eight and four other coumarins in bark, leaf and fruit respectively by comparison with their reported spectral data. During this study new Mammea A/AA 9-hydroxy-cyclo F and Mammea A/AB 9-hydroxy-cyclo F were identified. We believe that this protocol will be useful in case of dereplicative studies of Mammea and related species

Turbulent Magnetic Field Amplification from Spiral SASI Modes: Implications for Core-Collapse Supernovae and Proto-Neutron Star Magnetization

We extend our investigation of magnetic field evolution in three-dimensional flows driven by the stationary accretion shock instability (SASI) with a suite of higher-resolution idealized models of the post-bounce core-collapse supernova environment. Our magnetohydrodynamic simulations vary in initial magnetic field strength, rotation rate, and grid resolution. Vigorous SASI-driven turbulence inside the shock amplifies magnetic fields exponentially; but while the amplified fields reduce the kinetic energy of small-scale flows, they do not seem to affect the global shock dynamics. The growth rate and final magnitude of the magnetic energy are very sensitive to grid resolution, and both are underestimated by the simulations. Nevertheless our simulations suggest that neutron star magnetic fields exceeding $10^{14}$ G can result from dynamics driven by the SASI, \emph{even for non-rotating progenitors}.Comment: 28 pages, 17 figures, accepted for publication in the Ap

Actions de polyphénols de Clusiaceae sur l’endothélium vasculaire

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