Aysegul Peksel

The Effect of Combined Treatment with Niacin and Chromium (III) Chloride on the Different Tissues of Hyperlipemic Rats

We investigated the effects of a combined treatment with chromium (Cr) and niacin on the spleen, tongue, and lens tissues in terms of lipid peroxidation (LPO), glutathione (GSH), serum catalase (CAT), lactate dehydrogenase (LDH), serum cholesterol, and total lipid levels in normal and hyperlipemic rats. In this study, female 1-year-old Swiss albino rats were used. The rats were randomly divided into four groups. Group I rats (control) were fed with standard pellet chow. Group II rats were fed a lipogenic diet in which 2% cholesterol, 0.5% cholic acid, and 20% sunflower oil were added and were given 3% alcoholic water for 60 days. Group III rats were fed with the same lipogenic diet and were treated with a dose of 250 μg/kg body weight CrCI3·6H2O and 100 mg/kg body weight niacin, for 45 days, by gavage. The rats in group IV were fed with pellet chow and treated with 250 μg/kg body weight CrCI3·6H2O and 100 mg/kg body weight niacin, by gavage, for 45 days. After 2 weeks, the animals showed symptoms of hyperlipemia. On the 60th day, tissue and blood samples were taken. We have observed decreased CAT activity and GSH levels, increased LDH activity, cholesterol, total lipid, and LPO levels in hyperlipemic rats. Niacin and Cr administration to hyperlipemic rats increased tissue GSH levels and CAT activity and decreased tissue LPO levels and LDH activity, cholesterol, and total lipid levels compared with hyperlipemic rats. We conclude that the administration of a combination of niacin and chromium has a protective effect against oxidative damage to tongue, lens, and spleen tissues as a result of hyperlipemia.

Synthesis in solvent-free conditions, characterization and biological activity of a new Schiff-base ligand and its Cu(II) complex

A new bis-imine Schiff base (N8O2 donor, LH2) has been synthesized by melt condensation of 3-amino-1,2,4-triazole with 1,5-bis(2′-formylphenyl)-1,5-dioksapentane in 2 : 1 molar ratio, in solvent and solvent-free conditions. The ligand has been characterized using FTIR, UV–Vis, 1H NMR, 13C NMR, mass spectra, elemental analysis, and thermal (TGA-DSC) techniques. A new complex of LH2 with Cu(II) has been synthesized in solvent and solvent-free conditions. FTIR, UV–Vis mass spectra, and thermal analysis (TGA-DSC) have been used to characterize the Cu(II) complex. Thermal degradation showed that the final products were black carbon and metallic copper. Distorted octahedral geometry has been observed around CuLH2Cl2 · LH2 and its Cu(II) complex have been screened for in vitro antifungal and antioxidant activities. Antioxidation was determined for their superoxide scavenging and reducing activities. The ligand and its Cu(II) complex have strong antifungal activity against Aspergillus niger. The compounds have significant superoxide anion radical scavenging activity and reducing power against various antioxidant systems in vitro.

Effects of a combination of niacin and chromium(III)-chloride on the skin and lungs of hyperlipemic rats.

The aim of this study was to investigate the biochemical effects of niacin and chromium(III)-chloride on serum lipid peroxidation, uric and sialic acids, and the extent of lipid peroxidation and glutathione levels in skin and lung tissues of hyperlipidemic rats.In this study, female Swiss albino rats, 12 mo old, were used. They were randomly divided into four groups. Group I animals were fed with a standard pellet diet and water ad libitium. Group II rats were fed with a standard pellet diet and were treated with a dose of 250 μg/kg body weight CrCI3·6H2O and 100 mg/kg body weight niacin, for 45 d, by the gavage technique. Group III rats were fed a lipogenic diet in which 2% cholesterol, 0.5% cholic acid, and 20% sunflower oil were added to the pellet chow. In addition, the animals in this group drank water containing 3% ethanol. This regime was maintained for 60 d. The rats in group IV were maintained in the same food and drink regime as the animals in group III. After 2 wk, the animals showed symptoms of hyperlipemia and they were treated with 250 μg/kg body weight CrCI3·6H2O and 100 mg/kg body weight niacin, by gavage, for 45 d. On d 60, the blood and the skin and lungs samples were taken from animals.In the hyperlipemic groups, a reduction of the lung glutathione level and an increase in serum, lung, and skin lipid peroxidation levels and in serum sialic and uric acid were observed. In rats treated with a combination of niacin and Cr(III), the skin and serum lipid peroxidation and the sialic and uric acid levels decreased while showing an increase of lung glutathione activity. These results suggest that niacin and Cr(III), when administered in combination, have a protective effect against skin and lung tissues damage as a result of hyperlipidemia.

Antioxidant and radical scavenging activities of Asphodelus aestivus Brot. extracts

Asphodelus aestivus Brot. is a common spring-flowering geophyte encountered on the Marmara, Aegean, and Mediterrenean coasts of Turkey, which has been utilized traditionally for culinary and medicinal purposes. In the present study, different antioxidant tests were employed in order to evaluate the antioxidant activities of methanolic and acetone extracts of A. aestivus Brot. leaves. In addition, the results were compared with natural and synthetic antioxidants. The levels of total flavonoid, total chlorophyll, and total carotenoid contents of the extracts were also determined. Both extracts showed good total flavonoid content, inhibited lipid peroxidation, and showed radical scavenging activities.

Liquefaction/solubilization of low-rank Turkish coals by white-rot fungus (Phanerochaete chrysosporium)

Microbial coal liquefaction/solubilization of three low-rank Turkish coals (Bursa-Kestelek, Kütahya-Seyitömer and Muğla-Yatağan lignite) was attempted by using a white-rot fungus (Phanerochaete chrysosporium DSM No. 6909); chemical compositions of the products were investigated. The lignite samples were oxidized by nitric acid under moderate conditions and then oxidized samples were placed on the agar medium of Phanerochaete chrysosporium. FTIR spectra of raw lignites, oxidized lignites and liquid products were recorded, and the acetone-soluble fractions of these samples were identified by GC-MS technique. Results show that the fungus affects the nitro and carboxyl/carbonyl groups in oxidized lignite sample, the liquid products obtained by microbial effects are the mixture of water-soluble compounds, and show limited organic solubility.

Evaluation of the Antioxidative Properties of N-Acylamino-Substituted Tricyclic Imides

New N-acylamino-substituted tricyclic imides have been screened for scavenging ability against the free radical 2,2-diphenyl-1-picryl-hydrazyl (DPPH•), chelating activity on ferrous ions, and reductive potential. The results were compared with synthetic antioxidants BHT, BHA, and Trolox. The compounds exhibited different levels of antioxidant activity in all tests.

Radical scavenging and anti-acetylcholinesterase activities of aqueous extract of wild pistachio (Pistacia atlantica Desf.) leaves

The purpose of this work is to assess the radical scavenging activity, acetylcholinesterase inhibition, and proline content of an aqueous extract from wild pistachio (Pistacia atlantica Desf.) leaves. The effect of aqueous extract on superoxide radical scavenging, hydroxyl radical scavenging, N,N-dimethyl-1,4-phenylendiammoniumdichloride (DMPD·+) radical scavenging, ABTS·+ radical scavenging, nitric oxide scavenging, and β-carotene bleaching activities was examined. This study found that the aqueous extract possesses considerable amounts of flavonoids (33.52±2.04 μg catechin equivalents/mg of extract). The effect of this extract in scavenging activity of hydroxyl radical and DMPD·+ was significantly better than that of ascorbic acid and butylated hydroxyanisole (BHA). The effect of the extract in superoxide and ABTS·+ was significantly similar than that of tested standard antioxidants. The proline content of the extract was found to be 0.54±0.01 μg proline/mg of extract. Aqueous extract of P. atlantica inhibited acetylcholinesterase activity effectively with IC50 value of 58.05±0.12 μg/mL.

Radical scavenging and in vitro antifungal activities of Cu(II) and Co(II) complexes of the t-butylphenyl derivative of porphyrazine

Co(II) and Cu(II) complexes and metal-free t-butylphenyl peripherally substituted porphyrazine (Pz) have been screened for in vitro antifungal (Aspergillus niger) and antioxidant (free radical scavenging, superoxide radical scavenging, and reducing power) activities. The results were compared with synthetic antioxidants, e.g., butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), trolox, or α-tocopherol. The free radical scavenging activity of H2Pz was higher than the CuPz complex. However, CuPz complex showed higher superoxide radical scavenging activity than BHA, BHT, and trolox while H2Pz and CoPz showed weaker activity than BHA, BHT, and trolox. The reducing power of all complexes was similar to that of BHT and α-tocopherol on a per molar basis. The ligand and complexes have antifungal activity against A. niger. The compounds have significant superoxide radical scavenging activity against various antioxidant systems in vitro.

New p-Substituted Salicylaldehyde Phenylhydrazone Derivatives: Synthesis, Characterization, and Antioxidant Activities.

Abstract A series of new p-nitrophenylhydrazone derivatives 3a–f were synthesized, characterized, and investigated for their antioxidant activities. These compounds have been synthesized by refluxing (p-nitrophenyl)hydrazine with 4-sub-stituted salicylaldehydes. The structures of the compounds were established by IR, 1H- and 13C-NMR, and MS data. The antioxidant activities (free radical-scavenging activity, reducing power, metal chelating activity, and total anti-oxidant activity) of the hydrazone compounds were evaluated. All of the compounds exhibited significant activities, while compound 3a, with the shortest chain, showed the highest antioxidant activity in all of the tests.

Antioxidative properties of recently synthesised D-II-D type Schiff-base ligands

Two recently synthesised D–π–D type Schiff base ligands have been screened for their antioxidant capacity using several tests; reducing power, chelating ability on metal ions, scavenging capacity against the radicals 2,2-diphenyl-1-picrylhydrazyl, superoxide, hydroxyl, 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) and N,N-dimethyl-p-phenylenediamine dihydrochloride. The results were compared with synthetic antioxidants e.g. butylated hydroxytoluene, butylated hydroxyanisole, α-tocopherol, trolox or ascorbic acid. The results indicate that the ligands have significant hydroxyl and free radical scavenging activity, metal chelating effect and reducing power against various antioxidant systems in vitro. One ligand (L2) showed excellent activity on scavenging the ABTS radical and superoxide radical. Therefore, these ligands may be a new kind of effective scavengers of reactive oxygen species.