[show abstract][hide abstract] ABSTRACT: In order to examine the antioxidant properties of five different extracts of Trifolium pratense L. (Leguminosae) leaves, various assays which measure free radical scavenging ability were carried out: 1,1-diphenyl-2-picrylhydrazyl, hydroxyl, superoxide anion and nitric oxide radical scavenger capacity tests and lipid peroxidation assay. In all of the tests, only the H<sub>2</sub>O and (to some extent) the EtOAc extracts showed a potent antioxidant effect compared with BHT and BHA, well-known synthetic antioxidants. In addition, in vivo experiments were conducted with antioxidant systems (activities of GSHPx, GSHR, Px, CAT, XOD, GSH content and intensity of LPx) in liver homogenate and blood of mice after their treatment with extracts of T. pratense leaves, or in combination with CCl<sub>4</sub>. Besides, in the extracts examined the total phenolic and flavonoid amounts were also determined, together with presence of the selected flavonoids: quercetin, luteolin, apigenin, naringenin and kaempferol, which were studied using a HPLC-DAD technique. HPLC-DAD analysis showed a noticeable content of natural products according to which the examined Trifolium pratense species could well be regarded as a promising new source of bioactive natural compounds, which can be used both as a food supplement and a remedy.
[show abstract][hide abstract] ABSTRACT: Combinatorial bio/chemical approach was applied to investigate dioxin-like contamination of soil and sediment at the petrochemical and organochlorine plant in Pancevo, Serbia, after the destruction of manufacturing facilities that occurred in the spring of 1999 and subsequent remediation actions.
Soil samples were analyzed for indicator polychlorinated biphenyls (PCBs) by gas chromatography/electron capture detection (GC/ECD). Prioritized soil sample and sediment samples from the waste water channel were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). Microethoxyresorufin o-deethylase (Micro-EROD) and H4IIE-luciferase bioassays were used for monitoring of dioxin-like compounds (DLC) and for better characterization of dioxin-like activity of soil samples.
Bioanalytical results indicated high dioxin-like activity in one localized soil sample, while the chemical analysis confirmed the presence of large quantities of DLC: 3.0 × 10(5) ng/g d.w. of seven-key PCBs, 8.2 ng/g d.w. of PCDD/Fs, and 3.0 × 10(5) ng/g d.w. of planar and mono-ortho PCBs. In the sediment, contaminant concentrations were in the range 2-8 ng/g d.w. of PCDD/Fs and 9-20 ng/g d.w. of PCBs.
This study demonstrates the utility of combined application of bioassays and instrumental analysis, especially for developing and transition country which do not have capacity of the expensive instrumental analysis. The results indicate the high contamination of soil in the area of petrochemical plant, and PCDD/Fs contamination of the sediment from the waste water channel originating from the ethylene dichloride production.
Environmental Science and Pollution Research 11/2010; 18(4):677-86. · 2.62 Impact Factor
[show abstract][hide abstract] ABSTRACT: New non-covalent intermolecular fullerene system containing discrete C 60 and alcohol molecules have been prepared from the saturated solutions of fullerene in toluene with ethanol, methanol and isopropanol. The formation of intercalates with alcohols R-OH , C 60 (R C 1 -C 3) has not been described in the literature yet. Pure intercalates R-OH , C 60 were obtained in the direct synthesis of C 60 in toluene with R-OH (methanol, ethanol and isopropanol). UV and IR spectra of C 2 H 5 -OH , C 60 and C 3 H 7 -OH , C 60 showed no change compared to the pristine C 60 . However, IR spectrum of the methanol intercalate contains additional peaks at 2920 and 3400 cm 21 . There has also been no change in their diffraction images concerning the d-values (the diffractograms of powder), indicating that the compounds are isostructural with C 60 . The appearance of a very intensive d 101 peak in the powder diffractogram of the methanol derivative indicates that stacking disorder is probably eliminated, which can be correlated to the additional bands in IR spectrum. Intermolecular interactions (of the type that exists in supramolecular systems) between C 60 and alcohol molecules C 1 -C 3 exist because of the speci®c energy surfaces of C 60 molecule (the consequence of its electronic, vibrational and rotational properties) and the size, inductive, spatial and geometrical characteristics of intercalants (alcohols). The size and shape of the alcohols which form intercalates with C 60 is such that they nicely ®t within the intermolecular distances of C 60 molecules (0.293 nm) in a hexagonal lattice. q 1998 Elsevier Science B.V. All rights reserved
Journal of Molecular Structure - J MOL STRUCT. 01/2008; 471(1).
[show abstract][hide abstract] ABSTRACT: In this study level of soil contamination by polychlorinated biphenyls (PCBs) and polycyclic aromatic hydrocarbons (PAHs) in two oil refineries in Vojvodina region of Serbia was assessed using combined bio/chemical approach. Toxicity of the samples, determined by microEROD analysis, could not be exclusively attributed to the content of measured PCBs and PAHs, but also to the presence of unknown dioxin-like compounds (DLC), and/or positive interactions among similarly acting chemicals. The results proved that biotests, when applied in ecotoxicological assessments, should be used either as a screening tool or initial step in effect-directed analyses.
Bulletin of Environmental Contamination and Toxicology 11/2007; 79(4):422-6. · 1.11 Impact Factor
[show abstract][hide abstract] ABSTRACT: The antioxidant properties of open cage water-soluble fullerenol C60(OH)24 were tested by measuring their ability to scavenge stable 2,2-diphenyl-1-picryl¬hy¬dra¬zyl (DPPH) free radical and reactive hydroxyl radical (∙OH) during the Fenton reaction using electron spin resonance (ESR) spectroscopy. The fullerenol, obtained by newly developed method in our laboratory, scavenged bouth type of investigated radicals in dose-dependent manner in concentration range of 0.18-0.88 mmol/l. Generally, higher concentrations (0.71-0.88 mmol/l) of fullerenol possessed better inhibition of hydroxyl radical (50-82%) than of DPPH radical (28-50%).
Fullerenol can exhibit its antioxidative properties by simultaneous hydrogen atom donation to investigated free radicals (DPPH and ∙OH). This reaction also gave rise to the generation of the fullerenol radical C60(OH)23O. which presence was confirmed by ESR. Interaction between hydroxyl radical and fullerenol also based on radical-addition reaction of 2n .OH radicals to remaining olefinic double bonds of fullerenol core to yield C60(OH)24+2n.OH (n=1-12).
[show abstract][hide abstract] ABSTRACT: Investigation of the possible nitric oxide-scavenging activity of hydroxylated derivative of fullerene, fullerenol C60(OH)24, demonstrated that it expressed direct scavenging activity toward nitric oxide radical (NO) liberated within solution of sodium nitroprusside (SNP), a well known NO donor. In parallel, pre-treatment (30') with intratesticular injection of fullerenol (60 microg/each testis) prevented NO-induced decrease of catalase, glutathione transferase and glutathione peroxidase activities in the denucleated fraction of interstitial testicular cells of adult rats 2 h after intratesticular injection of SNP (20 microg/each testis). In addition, fullerenol decreased formation of thiobarbituric acid-reactive substances (TBA-RS) with similar efficiency as butylated hydroxy toluen (BHT), a well known antioxidant. Also, fullerenol expressed certain scavenging activity toward superoxide anion (O2-) in xanthine/xanthine oxidase system. In summary, results obtained in this study confirmed free radical-scavenging activity of fullerenol, and according to our knowledge, it is the first evidence of direct NO-quenching activity of hydroxylated C60 derivative in different milieu.