Rich extract on total polyphenols and antioxidant activity obtained by conventional and non-conventional methods from Ahmeur Bouamer grape seed

Conventional and non-conventional extraction methods were applied in the first time for the determination of total polyphenols from Ahmeur Bouamer, an anthoctonous variety grape seeds. Independently of the time and temperature, a positive effect of particle size parameter on maceration has been noted and relativly high concentrations in polyphenols for 500 μm (67.78 ± 0.46 mg GAE/gdm), 500-355 μm (90.95 ± 0.24 mg GAE/gdm) and 355-180 μm (114.82 ± 1.24 mg GAE/gdm) have been obtained. The higher value of yield was reached by the microwave extraction (37.74±0.32%), followed by the maceration (14.16±0.15%) and the ultrasound (6.70±0.25%). The appropriate extraction method to obtain a relatively strong antioxidant activity from seeds was the microwave with inhibition of 69.67±1.76 % and 78.05±2.05% of DPPH and ABTS+ free radicals, respectively.Keywords: Ahmeur Bouamer, extraction, grape seeds, total polyphenols, antioxidant activit

Antioxidant, antibacterial and cell toxicity effects of polyphenols Fromahmeur bouamer grape seed extracts

In this work and for the first time, significant concentrations of total polyphenols and flavonoids from Vitis vinifera L. grape seed extracts were obtained (256.15 ± 17.40 mg GAE/gdm and 14.08 ± 0.64 mg CE/gdm, respectively).The LC/MS analysis revealed richness in procyanidins. For antioxidant, antimicrobial and antifungal effects, the grape seed extract (GSE) responded positively. At 100 μg/mL, GSE induced a moderate toxicity of the order of 3.88% on 3T6 cells at the first 24 hours of treatment, whereas, its prolonged effect to 48 hours reduced this toxicity to less than 0.5%. As for the anti-proliferative effect on tumoral cell lines, a cell death of 18.39% to 23.79% and 10.30% to 20.37% was registered respectively for HeLa and BCPAP cells during 24 and 48 hours of treatment. Consequently, it is possible to consider using GSE at lower concentrations as an anti-proliferative agent without losing sight of its benefic effect on healthy cells.Keywords: grape seed extract, 3T6 cell, antioxidant, antibacterial, anti-proliferation

Catalog of Galactic Beta Cephei Stars

We present an extensive and up-to-date catalog of Galactic Beta Cephei stars. This catalog is intended to give a comprehensive overview of observational characteristics of all known Beta Cephei stars. 93 stars could be confirmed to be Beta Cephei stars. For some stars we re-analyzed published data or conducted our own analyses. 61 stars were rejected from the final Beta Cephei list, and 77 stars are suspected to be Beta Cephei stars. A list of critically selected pulsation frequencies for confirmed Beta Cephei stars is also presented. We analyze the Beta Cephei stars as a group, such as the distributions of their spectral types, projected rotational velocities, radial velocities, pulsation periods, and Galactic coordinates. We confirm that the majority of these stars are multiperiodic pulsators. We show that, besides two exceptions, the Beta Cephei stars with high pulsation amplitudes are slow rotators. We construct a theoretical HR diagram that suggests that almost all 93 Beta Cephei stars are MS objects. We discuss the observational boundaries of Beta Cephei pulsation and their physical parameters. We corroborate that the excited pulsation modes are near to the radial fundamental mode in frequency and we show that the mass distribution of the stars peaks at 12 solar masses. We point out that the theoretical instability strip of the Beta Cephei stars is filled neither at the cool nor at the hot end and attempt to explain this observation

Magnetic resonance imaging (MRI) contrast agents for tumor diagnosis

10.1260/2040-2295.4.1.23Journal of Healthcare Engineering4123-4