Effect of UVA radiation on interactions of infusions obtained from teasel (Dipsacus fullonum L.) with free radicals

An X-band (9.3 GHz) electron paramagnetic resonance (EPR) spectroscopy was used to examine the free radical scavenging activity of the following infusions, which were nonirradiated and exposed to UVA: root of Asparagus racemosus and herbs of Mitchella repens, Cnicus benedictus L., Galega officinalis L., and Eupatorium cannabinum L. The plant materials for obstetrics applications were chosen for analysis. The aims of these studies were to compare the free radical scavenging ability of the tested infusions and to determine the influence of UVA irradiation of the plant materials on interactions of these infusions with free radicals. Both the magnitude and kinetics of the interactions of the infusions with the model DPPH free radicals were examined. The ability to quench the free radicals for the examined plant infusions increases in the following order: Asparagus racemosus (root) < Mitchella repens (herb) < Cnicus benedictus L. (herb) < Galega officinalis L. (herb) < Eupatorium cannabinum L. (herb). The analyzed infusions differ in the kinetics of the interactions with free radicals. The fastest interactions with free radicals characterize the infusions of Galega officinalis L. herb and Eupatorium cannabinum L. herb. The infusion of Mitchella repens herb interacts with free radicals in the slowest way. UVA radiation reduces the antioxidant interactions of all tested infusions, especially the infusion of Eupatorium cannabinum L. herb, which should be protected against UVA radiation during storage. The weakest decrease of free radical scavenging activity was observed for the infusion of the root of Asparagus racemosus exposed to UVA radiation. UVA radiation affected the speed of the free radical interactions of the infusions, depending on the type of plant materials. EPR spectroscopy is useful to examine the free radical scavenging activity of plant infusions, which is helpful to find effective antioxidants for applications in obstetrics and their optimal storage conditions.

European elderberry (Sambucus nigra L.) fruits constitute a valuable source of biologically active compounds useful in the pharmaceutical industry. We aimed to determine the content of chosen polyphenolic compounds in fruit extracts from four cultivars of elderberry (Alleso, Korsor, Sampo, Samyl) and their relation to antibacterial and antifungal activity. The content of polyphenols was determined with the use of high-performance liquid chromatography (HPLC), while antimicrobial activity, including minimum inhibitory concentration (MIC), minimum bactericidal (MBC) or fungicidal (MFC) concentration, was studied with the use of microbroth dilution method. HPLC analysis revealed the presence of concentrations of cyanidin glycosides, caffeic and quercetin derivatives depending on the plant cultivar. The extracts exhibited the highest antibacterial activity against Staphylococcus spp. (MIC = 0.313 – 0.625 mg/mL) and Helicobacter pylori (MIC = 0.313 – 1.25 mg/mL) and antifungal against Candida albicans and C. parapsilosis (MIC = 0.313 – 2.5 mg/mL). Results showed that the concentration of cyanidin glycosides, caffeic and quercetin derivatives depended on the analyzed S. nigra L. cultivar and pointed towards a correlation between their high content and antimicrobial activity. These results support the idea that elderberry fruits contain bioactive compounds providing them significant antimicrobial potential.

The majority of essential oils obtained from medicinal plants have been demonstrated to be effective in the treatment of different kinds of diseases, and they are increasingly used in the diet. Due to their chemical composition, essential oils are a very interesting product of the secondary metabolism of plants, for both consumers and researchers. Among others, elderberry (Sambucus nigra L.) is mostly a woody plant, while it can rarely be found as a herbaceous perennial plant. This plant species has been used in traditional medicine because it is a very rich source of phytochemicals. The aim of this study was to identify and compare the composition of essential oils obtained from flowers and fruits of this plant, collected from the Balkan Peninsula. The oils were obtained using the Clevenger apparatus, and their composition was evaluated by gas chromatography - mass spectrometry (GC-MS). The oil composition was affected by the part of the plants used: the most abundant bioactive compounds in the essential oil of air-dried elderberry fruits were ?-damascenone (35.70%) and linalyl anthranilate (24.15%). ?-damascenone was the dominant compound in the essential oil of lyophilized elderberry fruits (38.64%), while linalool was detected in the concentration of 32.80%. In the essential oil of air-dried elderflowers, the most abundant compound was carane (13.19%). The essential oils of S. nigra shown substantial chemical composition and could be used as a potential source of natural products in the cosmetics and food industry.

In the search for clean energy conversion systems, PEM fuel cells have attracted a lot of attention over the last decades. Nanostructured electrocatalysts such as porous platinum nanoparticles (NPs) are considered one of the most promising advances to lower the cost of these fuel cells and make them more commercially attractive. The efficiency of these catalysts is limited by their activity towards the oxygen reduction reaction (ORR), and most research is thus focused on understanding reaction mechanisms and improving the activity. The mechanism is well understood for alkaline conditions, but there is still some debate for that under acidic conditions. It has been shown indirectly[1],[2] that radical intermediates formed during the reaction can desorb from the catalyst surface, but direct proof is still absent. More importantly, these free radicals are suspected to be responsible for the degradation of the carbon support, leading to the deactivation of the electrocatalyst NPs[3]. We propose an approach to detect and identify the free radicals produced during the ORR using electron paramagnetic resonance (EPR) spectroscopy. EPR spectroscopy combined with spin trapping has been shown to be useful for detecting radicals produced in electrochemical reactions[4],[5]. This method relies on binding the free oxygen radicals to the spin trap DMPO, forming the stable radical complex DMPO-OH•. The DMPO-OH complex can be detected using an EPR spectrometer. Custom-made glassy carbon RDE’s with a large geometrical surface area have been designed and were loaded with Pt nanoparticles via double pulse electrodeposition. The large surface area is necessary in order to produce sufficiently large amounts of free radicals to be detectable in the EPR spectrometer. A DMPO-OH• signal is formed and increases in strength for the duration of the ORR experiments. Furthermore, we observe a direct correlation between the charge produced during the experiment and the strength of the DMPO-OH• signal. This approach, capable of detecting the free oxygen radicals produced during the ORR, is employed to shed light on the ORR mechanism at carbon electrodes loaded with Pt NPs in acidic conditions.

The pharmaceutical product is a powdered tablets containing bisoprolol fumarate that is used in the treatment of circulatory system diseases. They were examined by X-band (9.3 GHz) electron paramagnetic resonance spectroscopy. The aim of this work was to determine the influence of the physical conditions of storage on the properties and content of free radicals in this pharmaceutical product. The product was subjected to a temperature of 50 °C, UVA radiation, and UVA radiation and then a temperature of 50 °C. The amplitude, integral intensity, linewidth of EPR lines, and g factor, were analyzed. Free radicals were formed in all tested samples; thus, the product containing bisoprolol fumarate should not be stored at a temperature of 50 °C, and it should be protected from UVA radiation, which is in line with the manufacturer’s requirements. The content of free radicals in the examined product was highest after treatment at a temperature of 50 °C. The lowest free radical content characterized the product after the interaction of both UVA radiation and a temperature of 50 °C. EPR lines were not microwave saturated below a power of 70 mW, which indicates fast spin-lattice relaxation processes in the product. It has been demonstrated that free radical formation in the product containing bisoprolol fumarate depends on the type of physical factor.

Elderberry fruit is available in the market and is becoming more popular. However, winemaking techniques are under-studied with this fruit. This study aimed to determine the impact of three processing methods on elderberry wine quality. The methods were: No extended maceration followed by hot water treatment (EC0); 2 days of cold soak maceration followed by hot water (EC2) and boiled elderberry (EB) fruits before alcoholic fermentation. The results indicated that although the treatments did not cause significant differences in ethanol, glycerol, total acidity, volatile acidity and tannins, wine pHs were influenced by the treatments. Besides influencing the pH, EB treatment produced darker elderberry wine, whereas, EC2 wine had the lightest color. Treatments also influenced the final wine monophenol profiles and antioxidant capabilities. EB wine had the highest total anthocyanin content and antioxidant activities. EC2 wine had a significantly higher amount of total hydroxycinnamates compared to EC0 but was not different from EB-treated wine. The wine antioxidant capacities were significantly lower than in musts but were not different between treatments. Cold maceration in EC2 did not help the extraction of antioxidants in elderberry wine. The results indicated that heating through boiling might help disrupt fruit cells and assist in the extraction of anthocyanins. Cold soak enhanced certain compounds in elderberry wines. This research provided information for elderberry fruit wine fermentation with general processing methods.

Purpose: Electron paramagnetic resonance (EPR) is a technique used to study materials with unpaired electrons (radicals). Alanine could serve as a radiation-detector material in which free radicals are produced after irradiation. Alanine has several features that make it suitable for medical dosimetry: tissue- equivalence, small size, small energy dependence of the response over a wide energy range, dose rate independence, low fading and the non-destructive readout. Last year, a new EPR spectrometer used for Alanine dosimetry was installed in the dosimetry laboratories of the Italian National Institute of Ionizing Radiation Metrology (ENEA-INMRI). In the following, we report on the methodology and preliminary results obtained on dosimeters irradiated in Ultra-High-Dose-Rate (UHDR) beam. Furthermore, an intercomparison with the EPR laboratory of the University of Palermo (UniPa) is performed. Materials and Methods: A Bruker-Elexsys spectrometer operating in the X band is used for EPR measurements in both laboratories. Alanine pellets used by ENEA are produced by Aerial (France), with 4 mm diameter, 2.3 mm height, and 35 mg average mass. These alanine pellets were calibrated in terms of absorbed dose to water in a 60Co gamma radiation at the CALLIOPE facility. Sensitivity variations of EPR spectrometer were monitored with a reference sample (alanine dosimeter irradiated at 1 kGy) measured during each section. The mean value of five repeated measurements was considered, obtained by randomly repositioning the sample in the cavity. The EPR spectrometer parameters used are: 6 mW microwave power, 2.5 mT sweep width and 1 mT modulation amplitude and 8 accumulations. Alanine pellets used by the University of Palermo are supplied by Gamma Service (Germany), with 4.9 mm diameter, 3.1 mm height, and 68.1 mg average mass. EPR experimental parameters included a 2.99 mW microwave power, a sweep width of 3 mT, an amplitude of modulation of 1 mT, and 4 accumulations. In this case, each pellet was measured four times, by modifying the orientation within the cavity, and the signal is given in terms of mean and standard deviation. The absorbed dose was estimated through a calibration curve (using a calibrated 60Co irradiation source) with doses ranging from 2.5 to 20 Gy. The sensitivity was also monitored with a standard pellet.All alanine dosimeters were irradiated in an electron UHDR beam at the CPFR (Centro Pisano Flash RadioTherapy) with a delivered dose of about 20 Gy. Specifically, the pellets were irradiated with a 9 MeV electron beam at different doses per pulse (from 0.026 Gy/p to 4 Gy/p). For each irradiation setup, nine alanine pellets were placed on a square PMMA holder array (four pellets from ENEA and five from UniPa) and irradiated at the buildup depth (about 14 mm) using solid water slabs. Results: The EPR measurements were performed in different sections and the results were normalized to the reference sample. For the ENEA pellets, the standard deviation in 5 repeated measurements is about 1%. For each irradiation setup, the comparison between pellets shows a standard deviation between 0.4% and 2%. These values corroborate the ones obtained by the intercomparison laboratory, in which the percent relative standard deviation for the same pellet is around 1 %, and between 0.6 and 3% for a set of pellets irradiated at the same dose. Conclusion: The preliminary results on the UHDR beam showed excellent reproducibility of the EPR spectrometer. Additionally, the results from the intercomparison demonstrated good agreement, despite the differences of pellet and signal acquisition parameters. In the next future, a new calibration will be planned in a clinical LINAC accelerator. Afterwards, a new set of measurements will be carried out in both conventional and UHDR beams. Furthermore, the EPR spectrometer could be applied also to study radicals in irradiated materials and in other sectors of ENEA-INMRI, as neutron dosimetry and radiodiagnostics.

New active ingredients, including those of plant origin, which could protect the skin against various harmful factors, such as UV radiation and free radicals responsible for skin ageing, are still being sought. The present study was focused on the antioxidant activity of Hippophaë rhamnoides L. and Vaccinium oxycoccos L. fruit glycolic extracts. Investigations were also carried out to evaluate the effect of UVA radiation and the storage of the sea buckthorn and European cranberry extracts at an elevated temperature of 50 °C on their interactions with free radicals. The kinetics of the interactions of the extracts with DPPH were assessed using electron paramagnetic resonance (EPR) spectroscopy. The sea buckthorn and European cranberry extracts quench the EPR signal of DPPH free radicals, which indicates their antioxidant potential. The EPR method further showed that a mixture of sea buckthorn and cranberry extracts in a volume ratio of 2:1 was more potent in quenching free radicals compared to a mixture of these extracts in a ratio of 1:2. Our findings demonstrate that long-term UVA radiation exposure reduces the ability of sea buckthorn and cranberry extracts to interact with free radicals. Moreover, storage at elevated temperatures does not affect the interaction of sea buckthorn extract with free radicals, while it alters the ability of cranberry extract to interact with free radicals. This study has demonstrated that an important factor in maintaining the ability to scavenge radicals is the storage of raw materials under appropriate conditions. H. rhamnoides and V. oxycoccos extracts can be used as valuable raw materials with antioxidant properties in the pharmaceutical and cosmetic industries.

This review article describes recently developed technologies in electron paramagnetic resonance (EPR) spectroscopy and imaging. Automatic control techniques used for a continuous-wave (CW) EPR spectrometer are discussed. These techniques can solve problems created by the motion of animals. Recent developments with time-domain EPR spectroscopy are also reported. Time-domain EPR spectroscopy is a technically challenging method because of the very short relaxation time that free radicals have in biological tissue. EPR imaging techniques are also reviewed, which are able to visualize free radicals in animal subjects non-invasively. Current status and future trends in the development of instruments for EPR spectroscopy and imaging are also presented, especially for biomedical applications. An important and powerful application of in vivo EPR spectroscopy and imaging is the detection of free radicals generated in biological specimens, which are so-called bioradicals. This article reviews these bioradicals, such as reactive oxygen species (ROS), free radicals generated from xenobiotics, metal ions, and common drugs, and it especially focuses on the direct-detection of bioradicals, rather than indirect detection. Drug-induced reaction mechanisms with hydrazine-based drugs, carcinogenic nitroso compounds, and prescription drugs for patients with hypertension (nifedipine) are discussed in detail based on in vivo studies with small animals. Metal-related reactions in vivo are also discussed with irons, chromate, and manganese. Keywords: continuous-wave (CW), superoxide dismutase (SOD), automatic frequency control (AFC), automatic tuning control (ATC), imaging technology

Electron paramagnetic resonance (EPR) examination of the effect of storage conditions on properties and contents of free radicals formed in the pharmaceutical preparation containing spironolactone, taking into account physical factors such as UVA radiation and the higher temperature, was conducted. The changes in amplitude (A), integral intensity (I) and EPR linewidth (ΔBpp) of the EPR spectra and free radical contents were determined. It was obtained that free radicals are formed during storage of this preparation under three different treatments: 50 °C, under UVA radiation, and under UVA radiation and a temperature of 50 °C. During storage, the preparation containing spironolactone should be protected from temperatures 50 °C and from UVA radiation. A higher content of free radicals is formed in the tested preparation exposed to both UVA and a temperature of 50 °C, than in the preparation exposed only to UVA or only to a temperature of 50 °C. Similar integral intensities (I) were obtained for the tested preparation exposed to a temperature of 50 °C or exposed to UVA radiation. Fast spin-lattice relaxation processes occur in all tested pharmaceutical preparation samples containing spironolactone. The usefulness of EPR spectral analysis in the study of free radicals formed in pharmaceutical preparations has been confirmed.

The article describes the varieties of elderberry, and the process of black elderberry fruits ripening. External characteristics of flowers, followed by ripening of fruits, have been described. The main components useful for the human body have been identified, which are contained in the fruits of the black elderberry. The effect of elderberry fruits on the human body when used for medicinal purposes has been. Elderberry fruits have a coloring substance that must be added to confectionery creams, sweets, marshmallows, as well as to liqueurs and wine products to give the products color and nutmeg taste. Elderberry fruits can be eaten fresh, ripe, but the most delicious and more useful fruits are provided in processed form, especially in juice and dried form. The useful properties of elderberry have been described, as well as the dangerous properties that appear in case of eating unripe elderberry fruits growing in the Republic of Belarus. The detailed composition of the components of elderberry fruit has been considered, all its useful properties noted. Particular attention is paid to the chemical composition of elderberry fruit, detailed amino acid composition of elderberry fruit has been given, and the composition of anthocyanin content in juice of direct extraction from elderberry fruit has been shown. The use of elderberry pomace in the food industry for the preparation of jam, jams, confiture, preserves and other products, as well as adding to wine, alcoholic beverages, to impart nutmeg taste, in the confectionery industry to add to dough and giving the product an almond smell has been described. It is especially noted that the pomace from elderberries contains biological active substances, bioflavonoids, anthocyanins, which confirms their immediate importance and the need to use for the creation of many products for preventive and functional purposes in the food industry.

The effect of UVA (315–400 nm) irradiation on Echinaceae purpureae interactions with free radicals was examined by the use of electron paramagnetic resonance (EPR) spectroscopy. The changes of antioxidant properties of E. purpureae with time of UV irradiation from 10 to 110 min (10 min steps) were determined. DPPH as the paramagnetic reference was used in this study. Changes of EPR signals of the reference after interactions with nonirradiated and UV-irradiated E. purpureae were detected. Interactions of the tested E. purpureae samples caused decrease of the EPR signal of DPPH as the result of its antioxidant properties. The decrease of the amplitude of EPR line of DPPH was lower for interactions with UV-irradiated E. purpureae. EPR examination confirmed antioxidant properties of E. purpureae. The weaker antioxidant properties of E. purpureae after UV irradiation were pointed out. E. purpureae should be storage in the dark. The tests bring to light usefulness of electron paramagnetic resonance with microwave frequency of 9.3 GHz (an X-band) in examination of storage conditions of pharmacological herbs.

Effects of UV-A irradiation and microbial fermentation on the physicochemical, microstructure and functional properties of okara

The types of free radicals formed by γ-irradiation in cellulose I and II were studied. The ESR spectra obtained with the γ-irradiated cellulose I and II were changed by contacting the fibers with water, and also the spectra for these fibers after immersion in water were varied by orientations of fiber axes to the magnetic field. These spectra seem to be related to the free radicals generated in the highly ordered regions inaccessible to water in irradiated cellulosic fibers. And the spectral differences between cellulose I and II may be due to the differences in the molecular conformation in the crystal lattices. As a model of typical amorphous regions in cellulose, decrystallized cellulose was prepared. The ESR spectrum of irradiated decrystallized cellulose was simple. When the sample was contacted with moisture, the ESR spectrum changed to a narrow singlet, which gradually decreased the intensity until the spectrum completely disappeared. By subtracting the spectrum of free radicals remaining in decrystallized cellulose after contacting with moisture from the spectrum of decrystal-lized cellulose, it was found that the types of free radicals formed in the decrystallized cellulose consisted of the overlap of narrow singlet (line width 8G, g-value 2.0050) and doublet (splitting 10G, g-value 2.0045) spectra. The singlet spectrum is attributed to alkoxyl radical formed by the rupture of glycosidic linkage at C1 or C4 position, and the doublet spectrum is ascribed to the radical formed by hydrogen abstraction from C1 position. When the ESR spectra of free radicals formed in the highly ordered regions of the irradiated cellulose I and II were added to the spectra of the singlet and doublet in adequate ratio, the constructed spectra were similar to the spectra of free radicals scavenged by water in cellulose I and II. From these facts the spectra generated by free radicals in the amorphous regions accessible to water in the irradiated cellulose I and II are considered to be composed of the ringlet and doublet formed by free radicals in the typical amorphous regions, and the spectra of other types of radicals, which are similar to the spectra for free radicals formed in crystal regions inaccessible to water. It is considered that the radicals are generated mainly in the typical amorphous regions in cellulose, since the contribution of the doublet spectrum is great in these constructed spectra for both cellulose I and II.

The immunosuppressive drugs used in solid organ transplantation or autoimmunological processes were studied by electron paramagnetic resonance (EPR) spectroscopy to estimate their free radical scavenging activity. The interactions of immunosuppressants with free radicals were examined by an X-band (9.3 GHz) EPR spectroscopy and a model of DPPH free radicals. The EPR spectra of DPPH and DPPH interacting with individual drugs were compared. Kinetic studies were performed, and the effect of ultraviolet (UV) irradiation on the free radical scavenging activity of the tested drugs was determined. The free radical scavenging activity of non-irradiated drugs decreased in the order: rapamycin>mycophenolate mofetil>ciclosporin>tacrolimus. UV irradiation increased the free radical scavenging activity of all the tested immunosuppressive drugs, and the effect was highest for tacrolimus. For the non-irradiated samples, the speed of free radical interactions decreased in the order: ciclosporin>tacrolimus>mycophenolate mofetil>rapamycin. UV irradiation only slightly affected the speed of interactions of the immunosuppressive drugs with the model DPPH free radicals. Electron paramagnetic resonance spectroscopy is useful for obtaining information on interactions of immunosuppressive drugs with free radicals. We hypothesized that the long-term immunosuppressive effects of these drugs after transplantation or during autoimmune disorders may be mediated by anti-inflammatory action in addition to the known receptor/cell cycle inhibition.