Fatih Çağlar Çelikezen

DNA damaging and biochemical effects of potassium tetraborate

Potassium tetraborate (PTB) is a product resulting from the controlled reaction of potassium hydroxide, water and boric acid (BA). It is used in many areas of industry such as disinfectant, detergent and treatment of contact lenses. PTB is one of the boron compounds which is most commonly used in many areas of industry although very limited information is available concerning its toxicity. Therefore, in this study, it is aimed to determine genetic and biochemical effects of PTB in human blood cell cultures (n=4). PTB was added into culture tubes at various concentrations (0-1280 µg/ml). Micronucleus (MN) and chromosomal aberration (CA) tests were performed for genotoxic damage influences estimation. In addition, biochemical parameters (total antioxidant capacity (TAC) and total oxidative status (TOS) were examined to determine oxidative effects. The results indicated that all tested concentrations of PTB were found to be non-genotoxic. In addition, low concentrations (1.25, 2.5 and 5 µg/ml) of PTB caused increases of TAC levels. Furthermore, all concentrations of PTB were not changed the TOS levels in cultured human blood cells. Based on these results, in this study it has been reported for the first time that PTB is not genotoxic and it increases the antioxidant capacity in human peripheral blood lymphocytes.

Synthesis of the 3,5-diphenyl-1H-pyrazole and cytogenetic and oxidative alterations after exposure of cultured human whole blood cells

Abstract The 3,5-diphenyl-1H-pyrazole was obtained by condensation reaction of dibenzoylmethane and thiosemicarbazide in acetic acid under conventional heating and microwave irradiation method. The structure of the 3,5-diphenyl-1H-pyrazole confirmed by IR, 1H, and 13C NMR and X-ray diffraction and the geometry optimization was carried out using density functional theory (DFT) methods at B3LYP/6-31G, 6-31G(d), 6-31G(d, p), 6-311G(d, p), 6-311G(2d, 2p), 6-31+G(d, p), 6-311++G(d, p) levels. In addition, cytotoxic and oxidative effects were investigated in cultured human peripheral blood cells.

In vitro assessment of genotoxic and oxidative effects of zinc borate

Zinc borate is used as flame retardant for plastics and cellulose fibers, paper, rubber, and textiles. Despite its wide industrial use, there is limited information concerning its toxicity. The aim of the present study was to investigate the concentration dependence (0–280 mg L−1) of its genotoxic activity on cultured human lymphocytes by using sister chromatid exchange and chromosomal aberration assays. Total antioxidant capacity and the extent of oxidative stress were also determined. Zinc borate was found to be non-genotoxic at all tested concentrations. It exhibited antioxidant activity at concentrations lower than 40 mg L−1, and total oxidative stress levels were not changed at any applied concentration of zinc borate.

Purification and characterization of polyphenol oxidase enzyme from Iğdir apricot (Prunus armeniaca L.)

In this study, polyphenol oxidase enzyme obtained from Iğdır apricot was purified with method of affinity chromatography. The apricot cultivar “şalak” was provided from Iğdır region. To purify polyphenol oxidase enzyme, obtained from Iğdır apricot, phosphate buffer at 7.3 pH was used and the homogenate was prepared. The homogenate was applied to activate sepharose 4B-tyrosine-paminobenzoic acid affinity column. For quantitative protein analyses, fractions obtained from column, and showing activity, was performed at 595 nm with coomassie blue method. In addition, optimum pH of enzyme, its optimum temperature, ionic strength effect and inhibition kinetics of some drugs and chemicals on enzyme were investigated. Optimum pH of enzyme and its optimum temperature were found to be 6 and 30oC, respectively. Furthermore, the study carried out on the ionic strength revealed that the highest activity was observed in concentration of 0.16 M (NH4)2SO4.