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1
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Impact of Vanadium(IV)-Oxy Acetylacetonate and Vanadium(III) Acetylacetonatel on the DPPC Liposome Membranes: EPR Studies

100%
Man D., Mrówka I., Wójcik A., Pytel B.
Acta Physica Polonica A
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2017
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vol. 132
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issue 1
52-56
EN
The effect of vanadium (IV)-oxy acetylacetonate (V4) and vanadium(III) acetylacetonate (V3) on the liposome membranes formed of synthetic lecithin (DPPC) was presented in this paper. Liposomes were formed during the sonication of DPPC lecithin in an aqueous medium. The concentration of the vanadium compounds changed in the range of 0% to 2.4% in molar ratio to the lecithin. The EPR technique made use of three spin probes penetrating the different areas of the membrane (as follows: TEMPO, 16-DOXYL stearic acid methyl ester, stearic acid 5-DOXYL methyl ester). TEMPO probe penetrates the interphase water-lipid (partition parameter F), the probe 16-DOXYL locates in the middle of the lipid bilayer (rotational correlation time τ), the probe 5-DOXYL gives a picture of membrane fluidity (the order parameter) just below the polar head groups. The results of our research showed the following conclusions. The change of membrane fluidity, as a function of admixture concentration, was dependent on the type of additives. TEMPO probe recorded an increase in liquidity interphase water-lipid for both admixtures: V3 and V4. 16-DOXYL probe indicated that the admixture V3 increases the fluidity in the center of the lipid bilayer. Admixture V4 significantly less impacted on the change of the membrane middle. The 5-DOXYL probe did not influence on the membrane surface portion, there were not observed significant changes under the impact of admixtures. V3 showed stronger impact on membrane fluidity.
2
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The Optimization of Antioxidant Properties of Herbal Bathing Salts

100%
Zawada K., Makarova K., Kowalska D., Wawer I.
Acta Physica Polonica A
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2017
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vol. 132
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issue 1
56-61
EN
The antioxidant properties 4 herbal infusions (of lavender flower, melissa leaf, verbena herb, and birch leaf), 2 salts (Dead Sea and Bochnia Mine salts) and 8 herbal salts (combination of herbal extract and salt) have been evaluated by 2,2-diphenyl-1-picrylhydrazyl-ESR (DPPH-ESR) test, ferric reducing antioxidant power and spin trap ESR using the Fenton reaction. The influence of herbal extracts and herbal salts on lipid membrane permeability has been studied with the spin probe ESR in the range of 293-323 K. The highest antioxidant activity was determined for melissa leaf preparations followed by birch leaf preparations in DPPH and ferric reducing antioxidant power assays whereas in the Fenton reaction the highest radical scavenging was observed for verbena herb and melissa leaf preparations. The lowest membrane permeability was observed in the presence of infusions of melissa and birch leaves, followed by corresponding herbal salts based on Bochnia Mine salt, and it was lower than in the reference system. On the other hand, lavender infusion increased the permeability of the model membrane, whereas the lavender salts decreased it. Therefore, the antioxidant activity of herbal infusions and salts towards skin could be inhibited by a lowered permeability. Thus, the combination of permeability studies with antioxidant studies in the presence of model lipids could be potentially used for optimization of other types of herbal bath salts.
3
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Impact of Plesiomonas Shigelloides Strain CNCTC 144/92 Lipopolysaccharide on DPPC Liposome Membranes: EPR Method

100%
Man D., Pytel B., Pisarek I.
Acta Physica Polonica A
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2017
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vol. 132
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issue 1
77-80
EN
Membrane fluidity measurements were performed for synthetic DPPC liposomes sonicated in aqueous solution and doped by Plesiomonas shigelloides strain CNCTC 144/92 (serotype O74:H5) lipopolysaccharide (LPS) extracted from the phenol (LPS_{PhOH}) and water (LPS_{H₂O}) phases. Concentrations of LPS in relation to DPPC ranged from 0 to 1.4% (molar ratio). The EPR spin probe method was used to describe physicochemical properties of different regions of the lipid bilayer. Since TEMPO spin probe dissolves both in the hydrophobic region of the membrane and in an aquatic environment it is possible to determine the spectroscopic partition parameter F, indicating the changes that occur in the water-lipid interface. The 16-DOXYL probe distributed in the middle of the lipid bilayer makes it possible to obtain the rotational correlation time τ parameter, which provides information about fluidity changes in the liposome membrane. Here we report that increasing concentrations (mainly in the range of 0.4-0.8%) of investigated LPS_{PhOH} and LPS_{H₂O} significantly influence spectroscopic parameters (F and τ). The surface area of the DPPC liposomes membranes was affected predominantly by LPS_{H₂O} while the lipid bilayer was most influenced by LPS_{PhOH}.
4
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Antioxidant Properties and Stability of Geissospermum Reticulatum Tinctures: Lag Phase ESR and Chemometric Analysis

76%
Sajkowska-Kozielewicz J. J., Gulik K., Makarova K., Paradowska K.
Acta Physica Polonica A
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2017
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vol. 132
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issue 1
68-73
EN
Geissospermum species are widely used in folk medicine in the Amazon region. This study was conducted to determine total phenolic and flavonoid contents of three tinctures of Geissospermum reticulatum barks from Peruvian Amazon and correlate these contents to the antioxidant activities and stability. Total content of phenolic compounds (from 694.91 to 1430.67 mg GAE/kg) and flavonoids (575.23-815.65 mg CAE/kg) were found by spectrophotometric methods. The obtained values were interpreted by artificial neural networks to describe the most beneficial conditions for tinctures. All tinctures have demonstrated the maximum of total flavonoid between 14 and 20 weeks of maceration, whereas the maximum of total flavonoid was between 25 and 30. The highest antioxidant properties were exhibited by tinctures in 3 different tests (ferric reducing ability of plasma, DPPH-ESR, oxygen radical absorbance capacity) after 35 weeks of maceration. The principal component analysis was employed to relate contents and properties. Results from the lag phase with α -(4-pyridyl-1-oxide)-N-tert-butylnitrone (POBN) spin trap studies at 60°C demonstrated that the stability of tinctures were related to total phenolic content. Thus, samples with 550-800 mg GAE/kg were more stable than those with higher total phenolic contents. The most beneficial conditions for bark tinctures depend on aimed final products, e.g. maximum of polyphenols or flavonoids and long-term stability. Further studies about content and storage conditions are needed.
5
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EMR Data on Mn(III; S=2) Ions in MnTPPCl Complex Modelled by Microscopic Spin Hamiltonian Approach

52%
Tadyszak K., Rudowicz C.
Acta Physica Polonica A
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2017
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vol. 132
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issue 1
15-19
EN
The electron magnetic resonance data on high-spin (S =2) manganese(III) 3d⁴ ion in tetraphenylporphyrinato chloride complex (MnTPPCl) obtained by high-frequency techniques are reanalysed. Preliminary results of semiempirical modeling of the spin Hamiltonian parameters for Mn(III) in MnTPPCl are presented. The microscopic spin Hamiltonian approach is utilized to predict the zero-field splitting and the Zeeman electronic parameters. It is found that for Mn(III) ions in MnTPPCl matching the experimental spin Hamiltonian parameters and the theoretical ones based on the ligand-field energy levels (Δ_{i}) within the ⁵D multiplet only may not be suitable for this system. Contributions due to the levels arising from the higher-lying ³H multiplet need to be taken into account in order to determine the reasonable values of microscopic parameters describing Mn(III) ions in MnTPPCl.
6
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Comparative Analysis of Experimental and Theoretical Zero-Field Splitting and Zeeman Electronic Parameters for Fe²⁺ Ions in FeX₂·4H₂O (X = F, Cl, Br, I) and [Fe(H₂O)₆](NH₄)₂(SO₄)₂

52%
Zając M., Rudowicz C.
Acta Physica Polonica A
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2017
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vol. 132
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issue 1
19-23
EN
Spectroscopic and magnetic properties of Fe²⁺ (3d⁶; S=2) ions at orthorhombic sites in FeX₂·4H₂O (X = F, Cl, Br, I) crystals are compared with those in [Fe(H₂O)₆](NH₄)₂(SO₄)₂ (FASH). The microscopic spin Hamiltonian modeling utilizing the package MSH/VBA enables prediction of the zero-field splitting parameters and the Zeeman electronic ones. Wide ranges of values of the microscopic parameters, i.e. the spin-orbit (λ), spin-spin (ρ) coupling constants, and the crystal-field (ligand-field) energy levels (Δp_{i}) within the ⁵D multiplet are considered to establish the dependence of the zero-field splitting parameters b_{k}^{q} (in the Stevens notation) and the Zeeman factors g_{i} on λ, ρ, and Δp_{i}. By matching the theoretical spin Hamiltonian parameters and the experimental ones measured by EMR, the suitable values of λ, ρ, and Δp_{i} are determined. The novel aspect is prediction of the fourth-rank zero-field splitting parameters and the ρ (spin-spin)-related contributions, not considered in previous studies. The MSH predictions provide guidance for high-magnetic field and high-frequency EMR measurements.
7
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Optimization of Antioxidant Properties of Creams with Berry Extracts by Artificial Neural Networks

52%
Makarova K., Zawada K., Wagner D., Skowyra J.
Acta Physica Polonica A
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2017
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vol. 132
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issue 1
44-51
EN
Oxidative stress and the excess of free radicals accelerate the ageing process of human skin. The application of skin cream with antioxidant compounds could reduce the damage caused by free radicals. In this work we studied two types of skin creams with extracts from aronia (Aronia melanocarpa), elderberry (Sambucus nigra) and bilberry (Vaccinium myrtillus) because of their high content of anthocyanins, i.e. strong natural antioxidants. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging ability of the skin creams with berry extracts were studied with ESR spectroscopy. The artificial neural networks were applied to optimize the berry extract concentration and storage time for oil-in-water and water-in-oil creams. Based on experimental results chokeberry and elderberry extracts in oil-in-water cream base revealed higher DPPH radical scavenging ability than in the corresponding water-in-oil. Artificial neural networks predicts maxima of DPPH radical scavenging for 1-week stored elderberry (2.23 mg DPPH/g) and 1-week stored chokeberry (5.84 mg DPPH/g) and bilberry (5.26 mg DPPH/g) 0.76% extracts in oil-in-water creams. The maxima of DPPH radical scavenging for water-in-oil creams were predicted for 6-week stored 0.8% aronia extract, freshly prepared 0.76% bilberry extract and 1-week stored 0.56% elderberry extract. The artificial neural networks predicted values are in good agreement with the experimental values. DPPH-EPR could be combined with artificial neural networks to optimize the extract concentration, and the type of cream base as well as to predict the effect of storage based on a limited number of experiments and samples.
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