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1
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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.
2
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Triplet States in DOPA-Melanin and in Its Complexes with Kanamycin and Copper Cu(II) Ions

80%
Najder-Kozdrowska L., Pilawa B., Buszman E., Więckowski A., Świątkowska L., Wrześniok D., Wojtowicz W.
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issue 4
613-618
EN
The mono- and biradical forms of DOPA-melanin (DOPA-eumelanin) were studied by EPR spectroscopy in 100-300 K temperature range. The existence of triplet states in DOPA-melanin was proved. The analysis of EPR spectra has shown that in DOPA-melanin and its complexes with kanamycin and Cu^{2+} ions, two kinds of paramagnetic centres exist. The first of them are in doublet ground state with spin S = 1/2 and they obey the Curie law. The paramagnetic centres of the second group are in thermally excited triplet state with spin S = 1 and in this case the Curie law is not fulfilled.
3
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Impact of Vanadium(IV)-Oxy Acetylacetonate and Vanadium(III) Acetylacetonatel on the DPPC Liposome Membranes: EPR Studies

80%
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.
4
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Antioxidant Properties and Stability of Geissospermum Reticulatum Tinctures: Lag Phase ESR and Chemometric Analysis

80%
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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ESR Studies of Paramagnetic Centers in Pharmaceutical Materials - Cefaclor and Clarithromycin as an Example

80%
Skowronska A., Wojciechowski M., Ramos P., Pilawa B., Kruk D.
Acta Physica Polonica A
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2012
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vol. 121
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issue 2
514-517
EN
Electron spin resonance (ESR) studies of two antibiotics, Cefaclor and Clarithromycin, have been performed in order to investigate concentration and dynamics of free radicals generated in these compounds due to thermal sterilization. For Cefaclor three combinations of temperature and heating time have been applied: 160°C, 170°C, 180°C for 120 min, 60 min, and 30 min, respectively, according to the pharmaceutical sterilization norm. Clarithromycin has been heated at 160°C for 120 min. The ESR lineshape has been investigated versus microwave power ranging from 2.2 mW to 70 mW. Electron spin-spin relaxation time has been estimated from the ESR lineshape analysis. Concentrations of radicals generated due to different sterilization procedures have been compared with the purpose to select the best sterilization scheme.
6
Content available remote

NMR Relaxation and ESR Lineshape of Anisotropically Rotating Paramagnetic Molecules

80%
Kubica A., Milewska A., Noinska M., Earle K., Kruk D.
Acta Physica Polonica A
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2012
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vol. 121
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issue 2
527-532
EN
The role of anisotropic rotation for electron spin resonance lineshape and nuclear magnetic relaxation dispersion profiles for paramagnetic molecules with electron spin quantum number S ≥ 1 is discussed. The ESR spectra and nuclear magnetic relaxation dispersion profiles are calculated by means of an approach based on the stochastic Liouville equation and referred to in the literature as "Swedish slow motion theory". This description is valid for arbitrary motional conditions and interaction strengths. Molecular tumbling influences the ESR spectra by modulating zero field splitting interactions. The nuclear spin relaxation is affected by the rotational motion in a twofold way: via the electron spin dynamics and as a direct source of modulations of the electron-nuclear dipole-dipole interactions. For coinciding principal axes systems of the permanent (residual, static) zero field splitting and rotational tensors the ESR lineshape is not affected by rotational anisotropy. Rotational anisotropy is important for nuclear relaxation as it is influenced by molecular rotation not only via the electron spin dynamics, but also directly by modulations of the electron spin-nuclear spin dipole-dipole interaction (when the dipole-dipole and zero field splitting frames do not coincide). The anisotropy effects depend strongly on the relative orientation of the dipole-dipole and permanent zero field splitting axes. Nevertheless, a different scenario is also possible. When the diffusion axis coincides with the dipole-dipole axis (but not with the principal axis system of the permanent zero field splitting), the nuclear spin relaxation as well as the ESR lineshape, become sensitive to the rotational anisotropy. The possible dependence of the ESR lineshape and nuclear spin relaxation on the rotational anisotropy should be carefully considered when attempting a joint analysis of ESR and nuclear magnetic relaxation dispersion results for paramagnetic molecules.
7
Content available remote

Impact of Plesiomonas Shigelloides Strain CNCTC 144/92 Lipopolysaccharide on DPPC Liposome Membranes: EPR Method

80%
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}.
8
Content available remote

Influence of Microwave Power on EPR Signal of Melanin Radical and Copper(II) Ions in DOPA-Melanin Complexes

80%
Najder-Kozdrowska L., Pilawa B., Więckowski A., Buszman E., Wrześniok D.
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EN
Electron paramagnetic resonance spectroscopy EPR was used for examination of microwave saturation in DOPA-melanin complexes with kanamycin and Cu(II) ions. The fast spin-lattice relaxation processes take place in system of paramagnetic metal ions. EPR signal of melanin radical saturated with growing of microwave power used during measurements. After adding Cu(II) ions a shortening of relaxation time is observed for EPR signal of melanin radical.
9
Content available remote

Optimization of Antioxidant Properties of Creams with Berry Extracts by Artificial Neural Networks

61%
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.
10
Content available remote

EPR Study of Gamma Irradiated Cholestanone Single Crystal

41%
Caliskan B.
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vol. 125
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issue 1
135-138
EN
Cholestanone (C_{27}H_{46}O) single crystals were irradiated with ^{60}Co-γ rays at room temperature. The spectra were recorded for different orientations of the crystal in the magnetic field at 120 K using the EPR technique. Radiation damage center was attributed to ĊHCH_2 CH_2 radical. The principal values of the hyperfine coupling tensor of the unpaired electron with the protons and the principal values of the g tensor were determined. The results were found to be in good agreement with the existing literature.
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