Saadettin Güner
Karadeniz Technical University
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Featured researches published by Saadettin Güner.
Journal of the Science of Food and Agriculture | 1998
Saadettin Güner; Barbaros Dincer; Nigar Alemdag; Ahmet Colak; Mehmet Tufekci
Proximate composition, selected mineral (Zn, Fe, Cd, As, Hg, Pb, Ni, Cu) content and fatty acid profiles were determined in some widely consumed fish species obtained from the Black Sea. All fish species analysed individually were fairly high in protein (14·1–25·1%) and lipid (7·4–18·4%). Moisture and ash content varied within a narrow range. The mineral content was highly variable. The most abundant microelements in fish were Zn and Fe followed by Cu, and the remaining elements were present in amounts below toxic levels. Eight fatty acids (16: 0, 16:1, n-7, 18: 0, 18:1 n-9, 18: 2 n-6, 20:1 n-9, 20: 5 n-3, 22: 6 n-3) represented more than 60% of the fatty acid content. Saturated fatty acids ranged from 25·8 to 45·1%. Anchovy and whiting contained almost 35% of polyunsaturated fatty acids. The percentage of docosahexaenoic acid (DHA) exceeded that of eicosapentaenoic acid (EPA) in almost all the fish species examined, and the actual content of these acids has shown that sprat, whiting, garfish, red mullet, shad and sea bream provide the recommended daily intake of 1 g of EPA+DHA with reasonable amounts of fillet. These results indicate that biological differences existing in fish species can influence the values to be set for the standards and composition.
Biometals | 2002
Nagihan Saglam; Ahmet Colak; Kerim Serbest; Sabriye Dülger; Saadettin Güner; Serdar Karaböcek; Ali Osman Belduz
Novel homodinuclear Cu(II) (K1), heterodinuclear Cu(II)-Mn(II) (K2) and homotrinuclear Cu(II) (K3) complexes with a novel oxime-type ligand have been prepared and their nucleolytic activities on pCYTEXP were established by neutral agarose gel electrophoresis. The analyses of the cleavage products obtained electrophoretically indicate that although the examined complexes induces very similar conformational changes on supercoiled DNA by converting supercoiled form to nicked form than linear form in a sequential manner as the complex concentration or reaction period is increased, K3 is less effective than the two others. The oxime complexes were nucleolytically active at physiological pH values but the activities of K1 or K2 were diminished by increasing the pH of the reaction mixture. In contrast, K3 makes dominantly single strand nicking by producing nicked circles on DNA at almost all the applied pH values. Metal complex induced DNA cleavage was also tested for inhibition by various radical scavengers as superoxide dismutase (SOD), azide, thiourea and potassium iodide. The antioxidants inhibited the nucleolytic acitivities of the oxime complexes but SOD afforded no protection indicating that the nucleolytic mechanism involves of copper and/or manganese complex-mediated reactive oxygen species such as hydroxyl radicals being responsible for the oxidative DNA cleavage.
Journal of Pharmaceutical and Biomedical Analysis | 2002
Ömer Dalman; Mehmet Tufekci; Sinan Nohut; Saadettin Güner; Serdar Karaböcek
3-[2-[2-(2-hydroxyimino-1-methyl-propylideneamino)-ethylamino]-ethyl-imino]-butan-2-one oxime, (H(2)mdo) reacts with copper(II) to form a highly stable 1:1 complex in alkaline medium at room temperature. The complex gives a maximum absorption at 570 nm with a molar absorptivity coefficient of 0.16 x 10(4) l mol(-1) cm(-1). A spectrophotometric method using this ligand was developed and optimized in terms of pH, stability of the complex, amount of reagent required, sensitivity, linearity and tolerance limits of various foreign ions. The linear range for copper determination is 0.2-225 mg l(-1). The method is sensitive, accurate and tolerant to many foreign substances, and, all the reagents used are stable under the conditions. Moreover, the method is easy to perform for the determination of copper in pharmaceutical and biological samples.
Journal of Inorganic Biochemistry | 1997
Serdar Karaböcek; Saadettin Güner; Nevin Karaböcek
Abstract Reaction of the binucleating ligand 6,6′-bis(5′-amino-3, ′4′-benzo-2′-thiapentyl)-1,11-diamino-2, 3:9, 10-dibenzo-4,8-dithiaundecane (H 4 L) with copper(II) salts in dried methanol (MeOH) results in the isolation of the mixtures of copper(I) and (II) complexes with Cl − and ClO 4 − counterions. The major products were the copper(I) complexes obtained pure after recrystallization from DMSO-MeOH. The ligands lose four protons from the amine functions to form copper(I) complexes of the general formula (Cu 2 L)X 2 , where X = Cl − , ClO 4 − . The complexes were oxidized to (Cu 4 L)X 4 with hydrogen peroxide in DMF. Cu(NO 3 ) 2 , on the other hand, gave [Cu 2 (H 4 L)(NO 4 ) 2 ](NO 3 ) 2 . The structure consists of two copper(I) and copper(II) atoms, each of which is coordinated through two thioether and two primary amine atoms. The two copper sites are linked through a saturated spiro carbon atom. The copper complexes were characterized by elemental analyses, molar conductivities, magnetic moments, and spectra (UV-Vis, IR).
Transition Metal Chemistry | 2001
Kerim Serbest; Serdar Karaböcek; Saadettin Güner; Fatma Kormali
A new ligand incorporating a dioxime moiety, 3-{2-[2-(2-hydroxyimino-1-methylpropylideneamino)ethylamino]ethylimino}butan-2-one oxime, (H2mdo), has been synthesized and its mono-, di- and trinuclear copper(II), and hetero-dinuclear copper(II)–manganese(II) complexes have been prepared and characterized by elemental analyses, magnetic moments, 1H- and 13C-n.m.r., i.r. and mass spectral studies. A mononuclear copper(II) complex of H2mdo was found to have a 1:1 metal:ligand ratio. Elemental analyses, stoichiometric and spectroscopic data of the metal complexes indicated that the metal ions are coordinated to the oxime and imine nitrogen atoms (C=N); the data support the proposed structure of H2mdo and its complexes.
Transition Metal Chemistry | 2001
Kerim Serbest; Ahmet Colak; Saadettin Güner; Serdar Karaböcek; Fatma Kormali
Novel mononuclear [Cu(HPnAO)H2O]ClO4(2), homodinuclear [Cu(PnAO)Cu(phen)(H2O)2](ClO4)2(3), homotrinuclear [Cu3(PnAO)2(H2O)2](ClO4)2(4) and heterodinuclear [Cu(PnAO)Mn(phen)2(H2O)](ClO4)2(5) complexes have been prepared from 3,3′-(1,3-propanediyldiimine)bis-(3-methyl-2-butanone)dioxime (H2PnAO) and characterized by elemental analyses, magnetic moments, i.r., u.v.–vis., and by mass spectral studies. The geometry of the metal chelates is discussed with the help of magnetic and spectroscopic measurements. I.r. spectra show that the ligand acts in a tetradentate manner and coordinates through the (C=N) and (N—H) groups. The elemental analyses, stoichiometry and the spectroscopic data of the complexes indicate that the copper(II) ions are coordinated by the ligand dianion. The heterodinuclear complex (5) displays in vitro ability to scavenge superoxide radicals produced by the xanthine–xanthine oxidase (XXO) system, using nitroblue tetrazolium as an indicator. The complex also supports aerobic growth of Escherichia coli (sodA−sodB−) in vivo in minimal media, indicating that complex (5) is a speculative potent SOD-mimic.
Food Chemistry | 1997
Mehmet Tufekci; Saadettin Güner
In recent years, Turkish black tea has been manufactured by a combination of orthodox + rotorvane + orthodox systems, especially developed for the conditions of Turkey. The optimum fermentation time of black tea manufactured by this system was investigated at the factory level by measuring the theaflavin contents during the fermentation step, which starts with rolling and ends with drying processes. Optimum fermentation times from the start of rolling in the ORO system were determined to be 83 min and 80 min for coarse tea and sieved fine tea, respectively, by theaflavin analysis. Low levels of theaflavin in Turkish black tea were attributed to the very low quality of the fresh tea leaves and of the plucking standards.
Transition Metal Chemistry | 2001
Kerim Serbest; Serdar Karaböcek; Saadettin Güner
A new binucleating ligand incorporating four oxime groups, butane-2,3-dione O-[4-aminooxy-2,3-bis-(2-hydroxyimino-1-methyl-propylideneaminooxymethyl)-but-2-enyl]-dioxime, (H4mto), has been synthesized and its dinuclear cobalt(III), copper(II), and homo- and hetero-tetranuclear copper(II)–manganese(II) complexes have been prepared and characterized by 1H- and 13C-n.m.r., i.r., magnetic moments and mass spectral studies. Elemental analyses, stoichiometric and spectroscopic data indicate that the metal ions in the complexes are coordinated to the oxime nitrogen atoms (C=N) and the data support the proposed structure for H4mto and its complexes. Moreover, dinuclear cobalt(III) and copper(II) complexes of H4mto have a 2:1 metal:ligand ratio.
Biometals | 2000
Sabriye Dülger; Nagihan Saglam; Ali Osman Belduz; Saadettin Güner; Serdar Karaböcek
Novel homotetranuclear Cu(II) and heteronuclear Cu(II)-Mn(II) complexes with tetrathioether-tetrathiol moiety have been prepared and their DNA relaxation activities with plasmid pCYTEXP (5kb) were electrophoretically established. The cleavage products analyzed by neutral agarose gel electrophoresis indicated that the interaction of the metal complexes with supercoiled plasmid DNA yielded linear, nicked or degraded DNA. The relaxation activities of both homo- and heterotetranuclear (SK4) complexes are time- and concentration-dependent. The findings suggest that SK4 with potent nucleolytic activity is a good nuclease substitute in the presence of cooxidant. Furthermore, the observation of induction of DNA into smaller fragments by SK4 is also significant.
Transition Metal Chemistry | 1998
Serdar Karaböcek; Saadettin Güner; Nevin Karaböcek
The novel binucleating ligand, 6,6 prime-methylene-bis(5 prime-amino-3 prime,4 prime-benzo-2 prime-thiapentyl)-1,11-diamino-2,3:9,10-dibenzo-4,8-dithiaundecane (H4L) was prepared and reacted with copper(II) salts in dry MeOH to yield mixtures of copper(I) and copper(II) complexes with Cl- and ClO-4 counter ions. The amine functions on the ligand release protons to form copper(I) complexes: (Cu2L)X2, where X=Cl−, ClO4-. The complexes were oxidized to (Cu2L)X4 with H2O2 in DMF; Cu(NO3)2 gave a different complex, [Cu2(H4L)(NO3)2](NO3)2, as regards proton releasing ability, coordination and oxidation number. Evidence for the structures of this new tetraamino-tetrathioether ligand and its copper complexes is provided by 1H-, 13C-n.m.r., mass, u.v.–vis., i.r. spectra, elemental analyses, molar conductivities and magnetic moments.The novel binucleating ligand, 6,6 prime-methylene-bis(5 prime-amino-3 prime,4 prime-benzo-2 prime-thiapentyl)-1,11-diamino-2,3:9,10-dibenzo-4,8-dithiaundecane (H4L) was prepared and reacted with copper(II) salts in dry MeOH to yield mixtures of copper(I) and copper(II) complexes with Cl- and ClO-4 counter ions. The amine functions on the ligand release protons to form copper(I) complexes: (Cu2L)X2, where X=Cl−, ClO4-. The complexes were oxidized to (Cu2L)X4 with H2O2 in DMF; Cu(NO3)2 gave a different complex, [Cu2(H4L)(NO3)2](NO3)2, as regards proton releasing ability, coordination and oxidation number. Evidence for the structures of this new tetraamino-tetrathioether ligand and its copper complexes is provided by 1H-, 13C-n.m.r., mass, u.v.–vis., i.r. spectra, elemental analyses, molar conductivities and magnetic moments.