Purpose
The purpose of this paper is to determine the antioxidant activity of natural polyphenols from larch wood by the amperometric method.
Design/methodology/approach
Direct measurements of ...antioxidant activity were carried out by the amperometric method in an oxidizing mode with glassy carbon as a working electrode, set potential +1.3V and using a flow-injection system with 2.2 mM phosphoric acid as the mobile phase with a flow rate of 1.2 ml/min.
Findings
The reported results show the following values of antioxidant activity for the tested compounds: (−)-secoisolariciresinol – 0.199 ± 0.002 mg/L (p < 0.05); isolariciresinol – 0.196 ± 0.002 mg/L (p < 0.05); lariciresinol - 0.222 ± 0.001 mg/L (p < 0.05); O-isopropylidene derivative of (−)-secoisolariciresinol - 0.143 ± 0.002 mg/L (p < 0.05); (+)-dihydroquercetin – 0.153 ± 0.002 mg/L (p < 0.05); and quercetin – 0.521 ± 0.001 mg/L (p < 0.05). The last product was tested as the reference of a widely used current antioxidant. General tendencies of determined values of antioxidant activity for studied compounds are in good correlation with published data as determined by the t-BuOOH-initiated lipid peroxidation method.
Practical implications
Described results show practical applicability of the amperometric method as being faster and cheaper in comparison to other methods, including oxygen radical absorbance capacity (ORAC) assay or 2,2′diphenyl-1-picrylhydrazyl (DPPH) reagent based assay.
Originality/value
The described results show the first-time application of the amperometric method for the evaluation of the antioxidant activity of phenolic compounds from larch wood.
In this work, the authors attempted to consider the influence of the geometry of the crystal lattice on the properties of nanowires, which manifest themselves in the process of uni-axial stretching. ...This work summarizes and systematizes the results of previous studies of the authors. The first group of samples – are typical FCC metal – Ni
3
Al. For these nanowires, deformation processes in directions with different packing densities of atoms , and were investigated. The second material group studied was an alloy with the non-cubic symmetry of the element cell CuAu I. Correspondingly, this sample was examined under deformation in directions corresponding to different lengths of the sides of the unit cell, and . All the investigations described in this paper were carried out by molecular dynamics method on three-dimensional models using the Morse's pair potentials.
Using the method of molecular dynamics, FCC Ni nanowires containing hydrogen atoms in octahedral and tetrahedral pores are investigated in the course of high-speed uniaxial tensile loading along the ...direction . The feature of structural transformations in Ni nanowires containing hydrogen is appearance on the stage of plastic deformation globular (spherical) formations consisting of hydrogen atoms
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