Investigation of antioxidant vitamins (A, E, C) and lipid peroxidation levels in rats injected N-(1,3-benzothiazol-2-yl)-N-(4,5-dihydro-1H-imidazol-2-yl) amine

The present study examined the influence of synthetic N-(1,3-benzothiazol-2-yl)-N-(4,5-dihydro-1H-imidazol-2-yl) amine (2-Amdz) on levels of vitamins A, E and C and malondialdehyde (MDA) in rats. A total of 30 rats, divided into two groups, were used in the study. The control group was given only a subcutaneous injection of 250 microL 75% ethanol, every other day. The other group of rats was administered a subcutaneous injection of 2-Amdz (25 mg kg-1, dissolved in 250 microL of 75% ethanol). Injections were continued for 16 days. After the application of 2-Amdz for 16 days, the serum levels of vitamins A, E and C and malondialdehyde (MDA) were determined by HPLC. The serum vitamin A, E, and C levels decreased significantly compared to controls (p<0.05) whereas serum MDA levels were higher than control levels (p<0.005). As a result, it can be suggested that 2-Amdz induced a severe stress and more importantly, increased the amount of free radicals and significantly decreased the levels of serum antioxidant vitamins.     

Electronic structure and related properties for quasi-binary (GaP)1−x (ZnSe) x crystals

The results of pseudopotential calculations of the band structure and related electronic and optical properties of quasi-binary (GaP)_1?x (ZnSe) _x crystals in the zinc blende structure are presented. Trends in bonding and ionicity are discussed in terms of electronic charge densities. Moreover, the composition dependence of the refractive index and dielectric constants are reported. The computed values are in reasonable agreement with experimental data. The results suggest that for a proper choice of the composition x, (GaP)_1?x (ZnSe) _x could provide more diverse opportunities to achieve the desired electronic and optical properties of the crystals which would improve the performances of devices fabricated on them.     

Antimicrobial and Antioxidant Properties of Total Polyphenols of Anchusa italica Retz

Anchusa italica Retz has been used for a long time in phytotherapy. The aim of the present study was to determine the antioxidant and antibacterial activities of extracts from the leaves and roots of Anchusa italica Retz. We first determined the content of phenolic compounds and flavonoids using Folin–Ciocalteu reagents and aluminum chloride (AlCl₃). The antioxidant activity was determined using three methods: reducing power (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant capacity (TAC). The antimicrobial activity was investigated against four strains of Escherichia coli, two strains of Klebsiella pneumoniae and coagulase-negative Staphylococcus, and one fungal strain of Candida albicans. The results showed that the root extract was rich in polyphenols (43.29 mg GAE/g extract), while the leave extract was rich in flavonoids (28.88 mg QE/g extract). The FRAP assay showed a strong iron reduction capacity for the root extract (IC₅₀ of 0.11 µg/mL) in comparison to ascorbic acid (IC₅₀ of 0.121 µg/mL). The DPPH test determined an IC₅₀ of 0.11 µg/mL for the root extract and an IC₅₀ of 0.14 µg/mL for the leaf extract. These values are low compared to those for ascorbic acid (IC₅₀ of 0.16 µg/mL) and BHT (IC₅₀ 0.20 µg/mL). The TAC values of the leaf and root extracts were 0.51 and 0.98 mg AAE/g extract, respectively. In vitro, the extract showed inhibitory activity against all strains studied, with diameters of zones of inhibition in the range of 11.00–16.00 mm for the root extract and 11.67–14.33 mm for the leaf extract. The minimum inhibitory concentration was recorded for the leaf extract against E. coli (ATB:57), corresponding to 5 mg/mL. Overall, this research indicates that the extracts of Anchusa italica Retz roots and leaves exert significant antioxidant and antibacterial activities, probably because of the high content of flavonoids and polyphenols.     

Investigation of suitable digestion methods for the determination of total phosphorus in soils

Total phosphorus in five soils with different compositions which were obtained from different places were extracted by using Na(2)CO(3) fusion, HClO(4) digestion, HClO(4) + HNO(3) digestion, HF + HClO(4) digestion or NaOBr oxidation methods. In order to test the suitability of the HF + HClO(4) digestion the results obtained by this method were compared with the others above, especially the Na(2)CO(3) fusion which is accepted as a standard method. The phosphorus amount found with the HF + HClO(4) digestion method were almost the same as the phosphorus amount by the Na(2)CO(3) fusion method, while the superiority in extracting phosphorus when compared to other methods were obvious. The methods used in the study were evaluated according to the recovery of total phosphorus, ease of application and rapidity with which they were performed. Orthophosphate in the soil extracts was determined by the molybdenum blue colour method. The relationships between methods are examined statistically.     

Calculation of Two-Center Nuclear Attraction Integrals over Integer and Noninteger n-Slater Type Orbitals in Nonlined-Up Coordinate Systems

Two-center nuclear attraction integrals over Slater type orbitals with integer and noninteger principal quantum numbers in nonlined up coordinate systems have been calculated by means of formulas in our previous work (T. Özdoan and M. Orbay, Int. J. Quant. Chem. 87 (2002) 15). The computer results for integer case are in best agreement with the prior literature. On the other hand, the results for noninteger case are not compared with the literature due to the scarcity of the literature, but also compared with the limit of integer case and good agreements are obtained. The proposed algorithm for the calculation of two-center nuclear attraction integrals over Slater type orbitals with noninteger principal quantum numbers in nonlined-up coordinate systems permits to avoid the interpolation procedure used to overcome the difficulty introduced by the presence of noninteger principal quantum numbers. Finally, numerical aspects of the presented formulae are analyzed under wide range of quantum numbers, orbital exponents and internuclear distances.     

C→N Migrations of the ethoxycarbonyl group in reactions of ortho-substituted aryl isocyanates with the 1,3-zwitterion derived from triisopropylphosphine and ethyl 2-cyanoacrylate

The reactions of meta—para-substituted aryl isocyanates with phosphorus-containing 1,3-zwitterions, which proceed with the CN migration of the CO₂Et group to form the corresponding carbamates, were extended to ortho-substituted aryl isocyanates. The influence of the steric and electronic effects of the ortho substituents in the aromatic rings of aryl isocyanates on the ease of this rearrangement is qualitatively considered.     

Assesment of dimethyl phthalate removal from aqueous phase using barium hexaferrite containing magnetic beads

The barium hexaferrite (BaFe(12)O(19)) containing magnetic poly (ethylene glycol dimethacrylate-vinyl pyridine; mag-poly [EGDMA-VP]) beads (average diameter=53-212 μm) were synthesized and characterized. Their use as an adsorbent in the removal of dimethyl phthalate (DMP) from an aqueous solution was investigated. The mag-poly (EGDMA-VP) beads were prepared by copolymerizing of 4-vinyl pyridine (VP) with ethylene glycol dimethacrylate (EGDMA). The mag-poly (EGDMA-VP) beads were characterized by N(2) adsorption/desorption isotherms (BET), vibrating sample magnetometer (VSM), X-ray powder diffraction (XRD), elemental analysis, scanning electron microscope (SEM), and swelling studies. At a fixed solid/solution ratio, the various factors affecting the adsorption of DMP from aqueous solutions such as pH, initial concentration, contact time, and temperature were analyzed. The maximum DMP adsorption capacity of the mag-poly (EGDMA-VP) beads was determined as 96.2 mg/g at pH 3.0, 25 °C. All the isotherm data can be fitted with both the Langmuir and the Dubinin-Radushkevich isotherm models. The pseudo-first-order, pseudo-second-order, Ritch-second-order, and intraparticle diffusion models were used to describe the adsorption kinetics. The thermodynamic parameters obtained indicated the exothermic nature of the adsorption. The DMP adsorption capacity did not change after 10 batch successive reactions, demonstrating the usefulness of the magnetic beads in applications.     

Heavy Metal Removal from Synthetic Solutions with Magnetic Beads Under Magnetic Field

The aim of this study is to prepare magnetic beads which can be used for the removal of heavy metal ions from synthetic solutions. Magnetic poly(ethylene glycol dimethacrylate‐vinyl imidazole) [m‐poly(EGDMA‐VIM)] beads were produced by suspension polymerization in the presence of magnetite Fe₃O₄ nano‐powder. The specific surface area of the m‐poly(EGDMA‐VIM) beads was found to be 63.1 m²/g with a size range of 150–200 µm in diameter and the swelling ratio was 85%. The average Fe₃O₄ content of the resulting m‐poly(EGDMA‐VIM) beads was 12.4%. The maximum binding capacities of the m‐poly(EGDMA‐VIM) beads were 32.4 mg/g for Cu²⁺, 45.8 mg/g for Zn²⁺, 84.2 mg/g for Cd²⁺and 134.5 mg/g for Pb²⁺. The affinity order on mass basis is Pb²⁺>Cd²⁺>Zn²⁺>Cu²⁺. Equilibrium data agreed well with the Langmuir model. pH significantly affected the binding capacity of the magnetic beads. Binding of heavy metal ions from synthetic wastewater was also studied. The binding capacities were 26.2 mg/g for Cu²⁺, 33.7 mg/g for Zn²⁺, 54.7 mg/g for Cd²⁺ and 108.4 mg/g for Pb²⁺. The magnetic beads could be regenerated up to about 97% by treating with 0.1 M HNO₃. These features make m‐poly(EGDMA‐VIM) beads a potential candidate for support of heavy metal removal under magnetic field.     

Multipronged Biomimetic Approach To Create Optically Tunable Nanoparticles

Current biomimetics for medical applications use a single biomimetic approach to imitate natural structures, which can be insufficient for reconstructing structurally complex natural systems. Multipronged efforts may resolve these complexities. To achieve interesting nanostructure‐driven optical properties, a dual‐biomimetic system contained within a single nanoagent was engineered to recapitulate chlorosomes, efficient light‐harvesting organelles that have unique dye assemblies and tunable photonic properties. A series of chlorin dyes was synthesized, and these hydrophobic assemblies were stabilized inside a high‐density lipoprotein, a second biomimetic that enabled in vivo utility. This system resulted in tunable tumor imaging of intact (photoacoustic) and disrupted (activatable fluorescence) nanostructures. The successful demonstration of this multipronged biomimetic approach opens the door for reconstruction of complex natural systems for biomedical applications.