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Deltamethrin (DM) is being used as a substitute for organochlorines and organophosphates in pest control because of its low environmental persistence and toxicity. But it has become an environmental contaminant as it has been used widely. In this study, we investigated the effect of DM (technical grade) on the antioxidant system of adult zebrafish. For this, six-month-old fish were exposed to 2, 4 and 6 μg/L of DM for 96 h. The tissues selected were liver and ovary. Our data showed that exposure to DM increases CAT (catalase), SOD (superoxide dismutase), GPx (glutathione peroxidase, antioxidant enzymes), LPO (lipid peroxidation, non-enzymatic antioxidant) and GST (glutathioneS-transferase, detoxifying enzyme) in liver and ovary. Increased GST could detoxify the toxicant; still there could be enough DM to cause oxidative stress. It appears from our study that zebrafish used compensatory mechanisms in eliminating reactive oxygen species. These data will be useful as oxidative stress is being used as a biomarker for aquatic pollution. [ABSTRACT FROM AUTHOR]

ContextAlthough olive mill wastewater (OMWW) is a good source of bioactive phenolic compounds, disposing OMWW is a serious environmental challenge. Production of wine via fermenting OMWW may be a promising alternative to deal with OMWW. However, whether or not olive wine from OMWW still reserves its original bioactivities remains unclear. ObjectiveThis study examines antioxidant activity of olive wine fermented from OMWW. Materials and methodsHydroxytyrosol in olive oil was determined by HPLC. Total flavonoid, total polyphenol andin vitroantioxidant activities were measured by spectrophotometry. Aged mice were intragastricly administered 7, 14 and 28 mL/kg olive wine consecutively for 30 d. Afterward, levels of malonaldehyde (MDA), protein carbonyl, reduced glutathione (GSH) and activity of superoxide dismutase (SOD) were assayed in mouse plasma and liver. ResultsContents of hydroxytyrosol, total flavonoid and total polyphenol in olive wine were 0.14 ± 0.01, 0.29 ± 0.06 and 0.43 ± 0.03 mg/mL, respectively. The IC50value of olive wine to scavenge DPPH and hydroxyl free radicals was 2.5% and 3.2% (v/v), respectively. Compared with the solvent control group, olive wine with a dose of 28 mL/kg remarkably lowered mouse MDA concentration in liver, and reduced protein carbonyl level in plasma (p < 0.05). Meanwhile, olive wine at doses of 7 and 28 mL/kg notably enhanced SOD activity in both mouse plasma and liver (p < 0.05). The beneficial effect on liver was superior to that of γ-tocopherol. ConclusionThe study demonstrated that olive wine from OMWW has potential for treating oxidative stress-associated diseases. [ABSTRACT FROM PUBLISHER]

Two-dimensional free energy surfaces for four rotamers ofcis-enol malonaldehyde in water have been investigated by umbrella sampling molecular dynamics (MD) calculations. Biasing potential used in the umbrella sampling calculation was adopted to be the minus of conformational free energy preliminary obtained by the thermodynamic integration MD calculations for the rigid malonaldehyde whose stretching and bending were all fixed. The calculated free energy surface shows that, in water, a rotamer that has an intramolecular hydrogen bond is most stable among the rotamers. This is the same as that in vacuum, while order of relative stability of the other three rotamers is different in water and in vacuum. Inclusion of intramolecular vibrations changed the free energy surface little, i.e. at most 2.6 kJ/mol, which is much smaller than the solvation free energy. Free energy barriers from the most stable intramolecular hydrogen bonded rotamer to the others are lowered by hydration but they are still very high, >50 kJ/mol, such that the malonaldehyde molecule spends most of its time in water taking this conformation. Thus, reaction coordinate for intramolecular proton transfer reaction in water may be constructed assuming this rotamer. [ABSTRACT FROM AUTHOR]

An improved torsional force field for cis-enol malonaldehyde is presented. First, the conformational potential energy has been calculated by ab initio method at MP2/6-31G** level as a function of two torsional angles around C–C and C–O single bonds. Then, the calculated 2D potential energy surface has been fitted to a potential function, where cross terms of the two dihedrals are added to the ordinary single cosine terms of the optimised potentials for liquid simulations all atom (OPLS-aa) type. The optimised function excellently reproduces the energies with the standard deviation as small as 1.9 kJ/mol. The function may be used easily in the molecular dynamics calculation. [ABSTRACT FROM PUBLISHER]

Pure malonaldehyde is obtained by organic synthesis. In the first step, malonaldehyde sodium salt is obtained by 1,1,3,3-tetramethoxypropane acidic hydrolysis and purified by recrystallization in methanol/ether. In the second step, malonaldehyde is synthesized by reaction between malonaldehyde sodium salt and gaseous hydrochloric acid dissolved in ether at - 40 °C. Finally, malonaldehyde is purified by pumping at temperatures less than 0 °C and extracted by sublimation. [ABSTRACT FROM AUTHOR]

Our previous work has shown that treatment of nucleosides with malonaldehyde simultaneously with acetaldehyde affords stable conjugate adducts. In the present study we demonstrate that conjugate adducts are also formed in calf thymus DNA when incubated with the aldehydes. The adducts were identified in the DNA hydrolysates by their positive ion electrospray MS/MS spectra, by coelution with the 2'-deoxynucleoside standards, and, in the case of adducts exhibiting fluorescent properties, also by LC using a fluorescence detector. In the hydrolysates of double-stranded DNA (ds DNA), two deoxyguanosine and two deoxyadenosine conjugate adducts were detected and in single-stranded DNA (ss DNA) also, the deoxycytidine conjugate adduct was observed. The guanine base was the major target for the malonaldehyde-acetaldehyde conjugates and 2'-deoxyguanosine adducts were produced in ds DNA at levels of 100-500 adducts/105 nucleotides (0.7-3 nmol/mg DNA). [ABSTRACT FROM AUTHOR]

This paper reports an approach to the analysis of the local anharmonic states of motion and tunnelling of hydrogen illustrated with the molecule malonaldehyde. A potential energy function is used accurately to fit the local potential energy surface. The basis fitting functions in the potential resemble the Morse basis function, [image omitted], but are intrinsically Gaussian: [image omitted]. After rearrangement to isolate the Gaussian operators, the new form of the potential allows the direct use of mathematically friendly (Gaussian) manipulations that are needed to carry out the quantum mechanical analysis of the anharmonic features, namely tunnelling. The quantal analysis uses Cartesian harmonic oscillator basis functions together with the Talmi-Moshinsky-Smirnov methods to evaluate matrix elements of the potential energy operator. The longer term objective of this kind of work is to develop practical methods of hybrid analysis with which to treat the local atom dynamics associated with a reactive species while the rest of the dynamics are modelled as simple harmonic oscillators. The goal is eventually to have a computational theory of proton/hydrogen or small molecular group transfer reactions in condensed-phase systems. This paper addresses only the detailed local dynamical analysis. [ABSTRACT FROM AUTHOR]

The immune cells, such as phagocytes and lymphocytes, which use reactive oxygen species (ROS) for carrying out many of their functions, need appropriate levels of intracellular antioxidants to avoid the harmful effect of oxidative stress. In previous studies, we have observed changes in several functions of those leukocytes from female BALB/c mice with lethal endotoxic shock caused by intraperitoneal injection of Escherichia coli 055:B5 lipopolysaccharide (LPS) (100 mg/kg), which were associated with high ROS production. In the present study, we have investigated the redox state of the above mentioned immune cells in that lethal endotoxic shock model measuring the oxidant/antioxidant balance through the following parameters: production of ROS, proinflammatory cytokine TNFα reduced glutathione (GSH), oxidized glutathione (GSSG), superoxide dismutase (SOD) and catalase (CAT) activities, malonaldehyde (MDA) and transcription factor NF-κB expression at different times after LPS injection. The results show an increase in ROS, TNFα and MDA production in both cell types, being higher in macrophages than in lymphocytes. GSSG/GSH ratio was increased in both macrophages and lymphocytes after LPS injection. With respect to the activity of the antioxidant enzymes SOD and CAT were decreased in both macrophages and lymphocytes. The activation of the transcription factor NF-κB was stimulated in macrophages and lymphocytes. These results point out that both lymphocytes and macrophages, which are able to play an important role in host response to endotoxin, show an oxidative stress thus contributing to the pathogenesis of this septic shock. [ABSTRACT FROM AUTHOR]