Biljana Bozin

Antioxidant and hepatoprotective potential of essential oils of coriander (Coriandrum sativum L.) and caraway (Carum carvi L.) (Apiaceae).

Essential oils of Coriandrum sativum L. and Carum carvi L. fruits were analyzed by gas chromatography-mass spectrometry and assayed for their in vitro and in vivo antioxidant activity and hepatoprotective effect against carbon tetrachloride (CCl(4)) damage. The in vitro antioxidant activity was evaluated as a free radical scavenging capacity (RSC), measured as scavenging activity of the essential oils on 2,2-diphenyl-1-picrylhydrazyl (DPPH(*)) and OH radicals and effects on lipid peroxidation (LP) in two systems of induction. Some liver biochemical parameters were determined in animals pretreated with essential oils and later intoxicated with CCl(4) to assess in vivo hepatoprotective effect. Tested essential oils were able to reduce the stable DPPH(*) in a dose-dependent manner and to neutralize H(2)O(2), reaching 50% neutralization with IC(50) values of <2.5 microL/mL for Carvi aetheroleum and 4.05 microL/mL for Coriandri aetheroleum . Caraway essential oil strongly inhibited LP in both systems of induction, whereas coriander essential oil exhibited prooxidant activity. In vivo investigation conferred leak of antioxidative capacity of coriander essential oil, whereas the essential oil of caraway appeared promising for safe use in folk medicine and the pharmaceutical and food industries.

Phenolic Compounds in Field Horsetail (Equisetum arvense L.) as Natural Antioxidants

In this paper, the study of antioxidant activity and phenolic composition of three different extracts (EtOAc, n-BuOH and H2O) of field horsetail (Equisetum arvense L.) is presented. The antioxidant activity has been evaluated measuring the total reducing power (expressed by Ascorbate Equivalent Antioxidant Capacity - AEAC), inhibition of lipid peroxidation, and free radical scavenging capacity (RSC) towards 2,2-diphenyl-1-picrylhydrazyl (DPPH radical) and nitric oxide (NO), respectively. In addition, the total flavonoid content (TFC) and phenolic constituents of each extract have been determined. The results obtained show that the highest RSC regarding both DPPH and NO radicals is expressed by EtOAc extract (EC50=2.37 μg/mL and EC50=90.07 μg/mL, respectively), and the lowest by H2O extract (EC50=37.2 μg/mL and EC50>333.33 μg/mL, respectively). n-BuOH extract showed the highest total reducing power (AEAC=13.40 μg/mL). Differences in the phenolic composition of examined extracts are found comparing the HPLC chemical profiles. Although, isoquercitrin is the main flavonoid in both EtOAc and n-BuOH extracts, a considerable amount of di-E-caffeoyl-meso-tartaric acid was presented in the n-BuOH extract. In H2O extract high content of phenolic acids and low percentage of flavonoids were detected.

Chemical Composition, Antioxidant and Antibacterial Properties of Achillea collina Becker ex Heimerl s.l. and A. pannonica Scheele Essential oils

The in vitro antioxidant and antimicrobial activities of two Achillea millefolium (Adanson) Koch s.l species essential oils (A. collina Becker ex Heimerl s.l. and A. pannonica Scheele, Asteraceae) originating from the Golija and Radan mountains (Serbia) were investigated. The chemical profiles of the essential oils were evaluated by GC-MS. Antioxidant activity was assessed as free radical scavenging capacity (RSC) towards 2,2-diphenyl-1-picrylhydrazil (DPPH) radicals, together with effects on lipid peroxidation (LP). Antibacterial activity was examined on 21 bacterial strains. Based on the chemical composition of the essential oil, A. collina s.l. from Mount Golija was classified as a chamazulene chemotype (tetraploid). The high percentage of oxygenated monoterpenes and absence of azulene in the essential oil obtained from A. pannonica from Radan pointing that this population is octaploid. Essential oil of A. pannonica expressed stronger antimicrobial activity on almost all tested bacteria. Furthermore, this essential oil expressed higher scavenging effects on DPPH radical (IC50 = 0.52 comparing to 0.62 μg/mL). Only in the LP evaluation, essential oil of A. collina s.l. from Golija exhibited stronger antioxidant activity (IC50 = 0.75 comparing to 2.12 μg/mL).

Antioxidant Activity of Nepeta nuda L. ssp. nuda Essential Oil Rich in Nepetalactones from Greece

Essential oils from air-dried leaves and verticillasters of Nepeta nuda ssp. nuda from Greece were analyzed by means of gas chromatography-flame ionization detection and gas chromatography-mass spectrometry. The dominant constituent in the verticillaster oils was 4aα,7α,7aß-nepetalactone (75.7%). The main metabolites of the leaf oil were 1,8-cineole (16.7%), 4aα,7α,7aß-nepetalactone (24.7%), and caryophyllene oxide (16.3%). The oils were examined for their antioxidant activity. Neutralization of stable 2,2-diphenyl-1-picrylhydrazyl radical ranged from 10.83% (2.50 μg/mL) to 58.64% (50.00 μg/mL) for verticillaster oil and from 6.25% (2.50 μg/mL) to 57.79% (50.00 μg/mL) for leaf oil. The essential oil from verticillasters had significant effects on lipid peroxidation (in the range of 41.18-59.23%), compared to tert-butylated hydroxytoluene (37.04%). In contrast, the essential oil from leaves exhibited pro-oxidant activity at the highest concentration applied.

Biomarkers of oxidative stress in amniotic fluid and complications in pregnancy

Objective. In this study, we tried to determine whether the activities of the primary antioxidant enzymes are detectable in amniotic fluid and whether they can be used as early biomarkers of complications in pregnancy such as pregnancy-induced hypertension (PIH), gestational diabetes mellitus (GDM), and bacterial vaginosis. Methods. This was a prospective study in which amniotic fluid was taken between 16 and 19 week of gestation. In all, 161 pregnant women were divided into two groups: study group – patients with the treated local infection, PIH, and GDM, and control group – healthy pregnant women. Levels of reduced glutathione (GSH) and activities of supeoxide dismutase (SOD), glutathione peroxidase (GSH-Px), glutathione reductase (GSHR), glutathione S-transpherase (GST), xanthine oxidase (XOD) and lipid peroxidation (LP) were determined spectrophotometrically in amniotic fluid samples. Results. Concentration of malondialdehyde varied greatly between investigated groups. XOD and SOD activities, though very low, were present in amniotic fluid samples. Also, enzymes of glutathione cycle and GSH concentrations were detectable and showed certain variations. Conclusion. Parameters of oxidative stress in amniotic fluid could be altered in certain pathological conditions. Their use as clinical biomarkers is limited due to great variations of amniotic fluid volume between patients which gives favor to hemolysate or serum of pregnant women.

Chemical Profile, Antioxidant and Antibacterial Activity of Thyme and Oregano Essential Oils, Thymol and Carvacrol and Their Possible Synergism

Abstract In this study, chemical composition, antioxidant and antibacterial activities of thyme and oregano essential oils, thymol and carvacrol, as well as their possible synergism were investigated. For chemical profiling of essential oils, GC-MS analysis was performed. Antioxidant capacity was assessed throughout neutralisation of DPPH and OH radicals. For determination of antibacterial activity against selected gram-positive (Staphylococcus aureus and Bacillus cereus) and gram-negative bacteria (Salmonella Infantis, Escherichia coli O157:H7) broth micro-dilution method was used. Finally, the combination testing for potential synergy of thyme and oregano essential oils, thymol and carvacrol was performed using checkerboard method and evaluated with fractional inhibitory concentration. Thymol and carvacrol were found to be dominant components of investigated essential oils. All studied samples expressed strong antioxidant and antibacterial potential. In synergy testing, both combinations (thyme/oregano essential oils and thymol/carvacrol) were found to have additive effect (FIC=0.75). These results confirm thyme and oregano essential oils, thymol and carvacrol as well as their combinations for possible application as natural additives in different products (food, cosmetics and nutriceuticals).

Bacterial vaginosis and biomarkers of oxidative stress in amniotic fluid

Objective: In this study we tried to determine if the activities of the primary antioxidant enzymes are detectable in amniotic fluid and if they can be used as early biomarkers of complications in pregnancy connected with bacterial vaginosis. Methods: This was a prospective study in which amniotic fluid was taken between 16 and 19 weeks of gestation. 161 pregnant women were divided into two groups: study group—patients with the treated local infection and control group—healthy pregnant women. Levels of reduced glutathione, and the activities of glutathione peroxidase, glutathione reductase, glutathione S-transpherase, xanthine oxidase, superoxide dismutase and lipid peroxidation were determined spectrophotometrically in amniotic fluid samples. Results: Concentration of malonyldialdehide (product of lipid peroxidation) varied greatly between investigated groups. Xanthine oxidase and superoxide dismutase activities, though very low, were present in amniotic fluid samples. Also, enzymes of glutathione cycle and reduced glutathione concentrations were detectable and showed certain variations. Conclusion: Although, biomarkers of antioxidant activity are present in the amniotic fluid, they are not differrent between women with and without bacterial vaginosis.

Variability of Content and Composition of Mentha aquatica L. (Lamiaceae) Essential Oil in Different Phenophases

Abstract The content and chemical composition of Mentha aquatica L. (Lamiaceae) essential oil during three phenophases (before flowering, flowering and after flowering) was compared. Quantities of the essential oils were determined according to the European Pharmacopoeia 4ed 12 and chemical profiles by GC-MS. The highest content of the essential oil was found before flowering stage (0.73%). The main constituent of the essential oil through all the three phenophases was menthofuran (19.0–24.5%), followed by 1,8-cineole (11.8–20.2%), E-caryophyllene (6.7–16.6%) and viridiflorol (7.6–9.0%). Although the composition of the essential oil in all the three investigated phenophases was generaly similar, some qualitative differences were observed (presence of α-guaiene, γ-murolene, valencene and germacrene B only before flowering, linalool and pulegone in the flowering stage, and α-thujene, geranyl acetate, α-bisabolol oxide and 1-octene-3-ol acetate after flowering). Furthermore, the differences in quantities of all compounds present in the essential oils were also recorded. However, the qualitative composition of main constituents of the essential oil in all the three investigated stages led to the suggestion that the menthofuran, as the major compound could be used as the stable chemosystematic marker in the Mentha aquatica L. taxonomy.

The Phenolics of the Ornithogalum umbellatum L. (Hyacinthaceae): Phytochemical and Ecological Characterization.

Ornithogalum umbellatum L. is a widely distributed species in Europe, that exhibits considerable variability at ecological, morphological, anatomical, and karyological level. Previous reports of the chemical investigations among Ornithogalum species indicate significant diversity of the secondary metabolites, as well. Knowing that environment affects the phenolic composition in plants to a large extent, the main objective of the research was to define relationship between phytochemical and ecological characters. To estimate an environmental influence on these results, plant material was collected at four habitats that differ in ecological factors and belong to two biogeographical regions: the Balkan Peninsula and the Pannonian Plane. Measured phytochemical characters are yield of dry extract, total phenolic and flavonoid contents, the presence of selected phenolic compounds as well as free‐radical scavenging activity (neutralization of DPPH and OH radicals). Results revealed that all analyzed phytochemical parameters differ between investigated O. umbellatum samples. The moisture level of habitat has the highest correlation, either positive or negative, with most of phytochemical characters, and is followed by temperature and soil reaction. Light intensity and nitrogen level have mostly moderate correlation coefficient with phytochemical characters. More complex correlation is revealed between ecological factors and nine phenolic compounds, with three observed patterns of relationship.

Effect of ELF-EMF on antioxidant status and micronuclei in K562 cells and normal lymphocytes

The effect of ELF-EMF on DNA through changes in antioxidative enzyme activities has not been sufficiently explored yet. The aim of this study was to determine ELF-EMF effect on antioxidative enzymes in cancer cell line and genotoxic potential on normal human lymphocytes. K562 cells were exposed to 50 Hz ELF-EMF (40 μT, 100 μT; 3 h, 24 h) and spectrophotometric determination of lipid peroxidation and antioxidative enzyme activities was conducted. Genotoxicity of ELF-EMF (50 Hz, 100 μT) was investigated by cytokinesis-block micronucleus assay in a normal human lymphocytes (exposure 24 h and 48 h). Results demonstrated that ELF-EMF did not alter the process of lipid peroxidation and superoxide dismutase activity. Catalase activity was increased only after application of 100 μT EMF for 24 h. Glutathione-S-transferase and -reductase activities were increased. Treatment with 100 μT ELF-EMF (24 h, 48 h) significantly reduced micronuclei incidence, while cell proliferation was significantly increased. Results indicate that 50 Hz ELF-EMF (40 μT, 100 μT) are week stressors which alone cannot generate enough ROS to induce process of lipid peroxidation in cancer cell line but strong enough to induce response of antioxidative system. Furthermore, 100 μT ELF-EMF in human lymphocytes did not exhibit genotoxic potential during 24 h and 48 h treatment, but stimulated cell proliferation.