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91.
Farhat Ullah Abdul Sadiq Abid Hussain Sajjad Ahmad Muhammad Imran 《Natural product research》2016,30(12):1440-1444
This study was designed to investigate antioxidant and anticholinesterase potential of Iris germanica var; florentina. Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory potential of plant samples were investigated by Ellman’s assay. Antioxidant activity was performed using DPPH, H2O2 and ABTS free radical scavenging assays. Total phenolics and flavonoids contents were expressed in mg GAE/g dry weight and mg RTE/g, respectively. In AChE inhibition assay, Ig.Fl, Ig.Sp and Ig.Cf fractions exhibited highest activity with IC50 values of < 0.1, 5.64 and 19 μg/mL, respectively. In BChE inhibitory assay, Ig.Fl, Ig.Sp, Ig.Cf and Ig.Cr were most active with IC50 of < 0.1, < 0.1, 31 and 78 μg/mL, respectively. In DPPH assay, Ig.Fl and Ig.Cf exhibited highest inhibition of free radicals, 80.52% (IC50 = 9 μg/mL) and 78.30% (IC50 = 8 μg/mL), respectively. In ABTS assay Ig.Cr, Ig.Cf, Ig.Fl and Ig.Sp exhibited IC50 values of < 0.1, 2, 2 and 3 μg/mL, respectively. 相似文献
92.
Ethylene polymerization was carried out by using a group of new dizirconium(IV) tetrapyrrole complexes as catalysts and MAO as co-catalyst under 1 atmosphere pressure of ethylene gas at 25 and 40°C. The highest value of catalyst activity was obtained
at 40°C by using bizirconium complexes including one calix[4]pyrrole between two zirconium centers and two terminal chlorines,
while zirconium(IV) complexes with coordinated THF, almost have not catalytic activity. The maximum catalytic activity mounted to 830 kg/mol·bar·h by Zr2(Cy4
Pyr
4)Cl4. The results show that the structure of the coordination sphere of zirconium(IV) has great influence on the rate of polymerization,
molar masses of forming polymer, and its molecular mass distribution.
Correspondence: Sajjad Mohebbi, Chemistry Department, University of Kurdistan, P.O. Box 66176-416, Sanandaj, Iran. 相似文献
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Molecular Diversity - Spirocyclic compounds fascinate the synthetic chemists due to their privileged ring system and efficacy in drug discovery. Many natural compounds comprise spirocyclic moiety... 相似文献
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Ion acoustic solitary waves in a quantum plasma, which is slowly rotating around an axis at an angle θ with the direction of magnetic field, are investigated. Quantum hydrodynamic model is under consideration with the effects of rotations which are included via Coriolis force. Fermions are degenerate and have different spin density states, that is, up and down characterized via parameter α. Linear analysis is performed by applying Fourier transformation to derive dispersion relation. For nonlinear analysis, we apply reductive perturbation method to derive Korteweg de Vries equation (KdV). The effects of variations of Coriolis force, spin polarization, and quantum parameter on characteristics of solitary structure are discussed. These results are applicable to astrophysical and laboratory plasmas. 相似文献