Person: YALÇIN, BAHATTİN
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YALÇIN
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BAHATTİN
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Publication Metadata only Nutrient dynamics and eutrophication in the Sea of Marmara: Data from recent oceanographic research(ELSEVIER SCIENCE BV, 2017) YALÇIN, BAHATTİN; Yalcin, Bahattin; Artuz, M. Levent; Pavlidou, Alexandra; Cubuk, Soner; Dassenakis, ManosThis work was implemented to study the physicochemical and biological characteristics of the Sea of Marmara and the Turkish straits (TSS: Bosporus and Dardanelles straits) for the period 2010-2013 and to calculate winter and summer fluxes of nutrients (nitrates, phosphates) between the Aegean and Black Seas through the TSS. The brackish Black Sea waters reach the Dardanelles Strait with modified biochemical properties. The salinity and phosphates of the surface waters increased westwards. Biologically labile nutrients of Black Sea origin are utilized through biological processes in the Marmara Sea. On the other hand, increase of nutrients due to land based sources has led to eutrophication problems in the area. The sub surface water layer of Mediterranean origin is oxygen depleted (saturation < 30%) and rich in nutrients. Higher oxygen values indicated water mixing of the Sea of Marmara during winter 2012. Ammonium was the predominant form of inorganic nitrogen. The study area has been classified from Moderate to Bad trophic status. Izmit Bay also faced serious eutrophication problems together with hypoxic conditions below the halocline. Nutrient fluxes through the TSS showed temporal variation in the upper and lower layers related to changes in both nutrient concentrations and the water mass volume fluxes. Surface nitrates and phosphates outflux from the Sea of Marmara to the Aegean Sea was higher than the influx from the Black Sea through Bosporus strait, indicating high enrichment of nutrients in the Sea of Marmara from anthropogenic sources. (C) 2017 Elsevier B.V. All rights reserved.Publication Metadata only Synthesis and characterization of Cu(II) complexes of pyrazine-2,3-dicarboxylicacid(PERGAMON-ELSEVIER SCIENCE LTD, 2011) YALÇIN, BAHATTİN; Tascioglu, Sulin; Aydin, Adnan; Yalcin, Bahattin; Kaki, Esra; Andac, Omer; Buyukgungor, Orhan; Kosar, BasakFour copper(II) coordination polymers, {[Cu(pz(COO)(2))(H2O)](4)center dot HBr}(n) (1). {[Cu(pz(COO)(2))(NH3)(2)]center dot H2O}(n) (2), {[Cu3H2(pz(COO)(2))(4)(H2O)(3)]center dot 2H(2)O}(n) (3) and {[Cu-2(pz(COO)(2))(2)(NH3)(2)(H2O)(3)][Cu(pz(COO)(2))(NH3) (H2O)(2)][Cu(pz(COO)(2))(NH3)(H2O)]center dot 2H(2)O}(n) (4) were synthesized using pyrazine-2,3-dicarboxylic acid, CuBr2, 2-(2-aminoethylamino)ethanol/triethanol amine/ammonia in a methanol:water (1:1) solution, and the mixed ligand complexes were characterized by spectroscopic methods, thermal and elemental analysis, and magnetic susceptibility. Complexes 2 and 4 were also characterized by means of single crystal X-ray crystallography. The characterizations show that the complexes have polynuclear molecular structures, except for complex 2, and all of the complex structures form polymeric chains. Complex 4 has a pseudo-merohedral twin structure. (C) 2011 Elsevier Ltd. All rights reserved.Publication Open Access Trace metal levels in edible wild fungi(SPRINGER, 2013-03) YALÇIN, BAHATTİN; Severoglu, Z.; Sumer, S.; Yalcin, B.; Leblebici, Z.; Aksoy, A.Metal levels (cadmium, cobalt, chromium, copper, iron, nickel, lead and zinc) of seventeen different edible wild fungi species (Agaricus campestris, Calocybe gambosa, Coprinus comatus, Hericium coralloides, Hydnum repandum, H. repandum var. rufescens, Lactarius deliciosus, L. salminocolor, Macrolepiota procera, Pleurotus ostreatus, P. ostreatus var. columbinus, Ramaria aurea, R. stricta, Rhizopogon luteolus, Sparassis crispa, Suillus bovinus, Tricholoma terreum) growing in Bolu-Turkey were measured by inductively coupled plasma optical emission spectrocopy. The obtained data were analyzed with statistical package for the social sciences statistics program. In addition, relation between metal concentrations in both soil and fungi samples were investigated. The highest metal concentrations in Bolu District, Turkey were measured in A. campestris (cadmium 0.270, chromium 2.735 and zinc 7.683), C. comatus (iron 160.12), M. procera (copper 15.990, cobalt 0.352 and nickel 3.645), R. luteolus (Pb 4.756) mg/kg dw (dry weight). As a result of the measurements, it was observed that metal uptake is related with the species of fungi and is also affected by pH and organic contents of the soil.Publication Metadata only Synthesis in water-free DMF, characterization, electrical, and gas sensing properties of bis[2-(2-aminoethylamino)ethanol]copper(II) dibromide(SPRINGER INTERNATIONAL PUBLISHING AG, 2013) YALÇIN, BAHATTİN; Tascioglu, Sulin; Yalcin, Bahattin; Dumludag, Fatih; Kaki, Esra2-(2-Aminoethylamino)ethanol (L) reacts with cupric bromide in dimethylformamide to give a mononuclear complex of Cu(II) [L2Cu]Br-2, with six-coordinate distorted octahedral geometry, in which two molecules of tridentate (N,N,O) ligand are involved. The structure was confirmed by spectroscopic methods, elemental and thermogravimetric analyses, and magnetic measurements. Optimization of possible configurations indicated the formation of the trans structure of the complex. Experimental results indicate that the investigated complex, bis[2-(2-aminoethylamino)ethanol] copper(II) bromide, behaves as a semiconductor in the studied temperature range of 298-388 K. Gas sensing properties of the film for the volatile organic compounds (VOCs): acetone, tetra-chloromethane, chloroform, ethanol, and methanol, were also investigated as a function of vapor concentration and temperature in dark. The film showed maximum sensitivity to tetrachloromethane and ethanol vapors at room temperature. Responses of the film to the tested gases are reversible.Publication Metadata only Synthesis, characterization, crystal structure, electrochemical studies and biological evaluation of metal complexes with thiosemicarbazone of glyoxylic acid(PERGAMON-ELSEVIER SCIENCE LTD, 2018) ÖZKAYA, ALİ RIZA; Huseynova, Mansura; Taslimi, Parham; Medjidov, Ajdar; Farzaliyev, Vagif; Aliyeva, Mahizar; Gondolova, Gulnar; Sahin, Onur; Yalcin, Bahattin; Sujayev, Afsun; Orman, Efe Baturhan; Ozkaya, Ali Riza; Gulcin, IlhamiCobalt and nickel nitrates form with thiosemicarbazone of glyoxylic acid (H(2)GAT) complexes of empirical composition Co(C3H4N3O2S)(2)center dot 2H(2)O, Ni(C3H4N3O2S)(2)center dot 2H(2)O and Ni(C3H6N3O2S)(2). X-ray diffraction studies have shown that the Co(HGAT)(2)center dot 2H(2)O, Ni(HGAT)(2)center dot 2H(2)O complexes are mononuclear, in which the coordination around the metal is octahedral, made up of two sulfur atoms, two nitrogen atoms and two oxygen atoms from two ligands. By the interaction of NiCl2 center dot H2O with 2-[2-(aminothioxomethyl)hydrazinyl] acetic acid (H(2)TAA) instead of the expected the metal thiosemicarbazonate complex with the hydrogenated on the azomethine group ligand was obtained. The redox properties of these compounds were also investigated by voltammetry on Pt in dimethylsulfoxide/tetrabutylammonium perchlorate. These thiosemicarbazone of glyoxylic acid derivatives had effective inhibition against alpha-glycosidase, cytosolic carbonic anhydrase I and II isoenzymes, butyrylcholinesterase and acetylcholinesterase. K-i values were found as 26.12-36.58 nM for hCA I, 20.73-40.78 nM for hCA II, 184.30-642.18 nM for AChE, 123.67-342.37 nM for BChE, and 14.66-45.62 nM for alpha-glycosidase. (C) 2018 Elsevier Ltd. All rights reserved.Publication Metadata only Synthesis and characterization of novel 7-oxy-3-ethyl-6-hexyl-4-methylcoumarin substituted metallo phthalocyanines and investigation of their photophysical and photochemical properties(ROYAL SOC CHEMISTRY, 2019) YALÇIN, BAHATTİN; Ozdemir, Mucahit; Karapinar, Begumhan; Yalcin, Bahattin; Salan, Umit; Durmus, Mahmut; Bulut, MustafaIn this study, the synthesis of novel 7-hydroxy-3-ethyl-6-hexyl-4-methylcoumarin (1), four respective phthalonitriles; 4-(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin)phthalonitrile (2), 3-(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin)phthalonitrile (3), 4-chloro-5-(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin)phthalonitrile (4), and 4,5-bis(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin)phthalonitrile (5) and their corresponding alpha tetra, beta tetra and beta octa 7-oxy-3-ethyl-6-hexyl-4-methylcoumarin and beta octa 4-chloro-5-(7-oxy-3-ethyl-6-hexyl-4-methylcoumarin) substituted Zn(ii) (6a-9a) and In(iii) Cl (6b-9b) phthalocyanines has been performed. The novel purified compounds were characterized by standard characterization techniques such as elemental analysis, thermal analysis, FT-IR, UV-vis, H-1-NMR and MALDI-TOF mass spectrometry. All of the obtained phthalocyanines showed lipophilic behaviour with excellent solubility in organic solvents such as acetone, dichloromethane, chloroform, pyridine and ethyl acetate. The fluorescence quenching behaviour was investigated using 1,4-benzoquinone and potassium iodide as quenchers. The photophysical (fluorescence quantum yields and lifetimes) and photochemical (singlet oxygen and photodegradation quantum yields) properties of these novel phthalocyanines (6a-9a and 6b-9b) were studied in DMF. They produced high singlet oxygen (for example phi(Delta) = 0.99 for 7b) and showed appropriate photodegradation (in the order of 10(-5)) which is very important for photodynamic therapy (PDT), and thus these phthalocyanines can be used as Type II photosensitizers in PDT applications.Publication Metadata only Synthesis, Spectral Characterization and Antimicrobial Activity of Some Transition Metal Complexes of 1,3-Bis(1H-benzimidazol-2-yl)-2-oxapropane(WILEY-V C H VERLAG GMBH, 2014) YALÇIN, BAHATTİN; Tavman, Aydin; Cinarli, Adem; Gurbuz, Demet; Tan, A. Seher Birteksoz; Oksuzomer, M. A. Faruk; Tuysuz, Mayram; Gurkaynak, Mehmet Ali; Yalcin, Bahattin1,3-Bis(1H-benzimidazol-2-yl)-2-oxapropane (L) complexes with Fe(NO3)(3), CoCl2, Co(NO3)(2), Ni(NO3)(2), CuCl2, Cu(ClO4)(2), PdCl2, CdI2, Hg(NO3)(2) were synthesized and characterized by elemental analysis, molar conductivity, magnetic moment, TGA, FT-IR, NMR, ESI-MS, fluorescence spectroscopy. Also, the crystal structure of 1,3-bis(1H-benzimidazol-2-yl)-2- oxapropane] dichlorocobalt(II), [Co(L)Cl-2], complex is reported that it has distorted trigonal bipyramidal geometry. Antibacterial activities of the compounds were evaluated using the disk diffusion method against six bacteria and Candida albicans. The Hg(II) complex shows superior activity toward S. epidermidis and E. coli whereas the other complexes are ineffective except the Co(NO3)(2) complex: it showed weak activity toward all of the microorganisms.Publication Open Access Determination of carbohydrate amounts of various cheese species presented to sale in the market(2018-11-30) CEBECİ, AYBİKE; YALÇIN, BAHATTİN; GÜNEŞ, FATMA ESRA; Aybike Cebeci, Mustafa Yaman, Bahattin Yalcin, Fatma Esra GunesThe aim of this study is to determine the amounts of lactose, glucose, galactose, starch and total carbohydrates in cheese types presented to sale in the market. In the study, from different points of sale in Istanbul province 15 different types of cheese were investigated. Carbohydrate amounts of the cheeses examined were determined in two ways as theoretically (by difference method) and analytically (by HPLC). The amount of analytically determined carbohydrate of white cheese types was lower than the theoretically calculated amount (P<0.05). However, there was no statistically significant difference between the theoretical and analytically calculated carbohydrate amounts of kashar and other cheese types (P>0.05). In addition, it was determined that the amount of carbohydrates of ripened cheeses was lower than carbohydrate amounts in fresh cheeses. Consequently, analytical calculation of carbohydrate amount gives more accurate results. This should be taken into account when evaluating the macronutrient content of cheese.Publication Metadata only Investigation of Heavy Metal Level and Mineral Nutrient Status in Widely Used Medicinal Plants' Leaves in Turkey: Insights into Health Implications(HUMANA PRESS INC, 2018) YALÇIN, BAHATTİN; Ozyigit, Ibrahim Ilker; Yalcin, Bahattin; Turan, Senay; Saracoglu, Ibrahim Adnan; Karadeniz, Sedat; Yalcin, Ibrahim Ertugrul; Demir, GokselThe use of plants in treatments has been as old as humanity and it has preserved its popularity for centuries til now because of their availability, affordability and safeness. However, despite their widespread use, safety and quality issues have been major concerns in the world due to industrial- and anthropogenic-based heavy metal contamination risks. Thus, this study was attempted to analyze the heavy metal levels and mineral nutrient status of widely used medicinal plants in Turkey to have insights about their health implications on humans. The plant concentrations of B, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb and Zn were analyzed by ICP-OES in the leaves of 44 medical plants purchased from herbal markets of three different districts of Istanbul/Turkey. The measured lowest to highest concentrations were 0.065-79.749 mg kg(-1) B, 921.802-12,854.410 mg kg(-1) Ca, 0.020-0.558 mg kg(-1) Cd, 0.015-4.978 mg kg(-1) Cr, 0.042-8.489 mg kg(-1) Cu, 34.356-858.446 mg kg(-1) Fe, 791.323-15,569.349 mg kg(-1) K, 102.236-2837.836 mg kg(-1) Mg, 4.915-91.519 mg kg(-1) Mn, 10.224-3213.703 mg kg(-1) Na, 0.001-5.589 mg kg(-1) Ni, 0.003-3.636 mg kg(-1) Pb and 2.601-36.102 mg kg(-1) Zn. Those levels in plants were in acceptable limits though some elements in some plants have high limits which were not harmful. Variations (above acceptable limits) in element concentrations also indicated that these plants could be contaminated with other metals and that genetic variations may influence accumulation of these elements at different contents. Overall, analyzed medicinal plants are expected not to pose any serious threat to human health.Publication Metadata only Cu(II) complex with thiosemicarbazone of glyoxylic acid as an anion ligand in a polymeric structure(ELSEVIER SCIENCE BV, 2019) YALÇIN, BAHATTİN; Huseynova, Mansura Teyfur; Aliyeva, Mahizar Nacaf; Medjidov, Ajdar Akber; Sahin, Onur; Yalcin, BahattinA new complex of Cu(II), the composition Cu(C3H7N3O4S)center dot H2O, the reaction of thiosemicarbazone glyoxylic acid with copper nitrate in an aqueous medium was synthesised. X-ray diffraction analysis established the composition of the complexes was studied by IR, UV electronic absorption and EPR spectroscopy, and thermogravimetry. Thermogravimetry shows five stages of decomposition in the temperature range 90-990 degrees C. The magnetic susceptibility of the complex is studied. The value of mu(eff) for the complex is 1.76 BM, which is close to the value of one unpaired electron (1.73 BM). The ligand coordinates with the metal atom and consists of monoanionic Cu(C3H7N3O4S)center dot H2O polymeric complex connected by Cu-N bonds with neighbouring molecules. The metal centre coordinates with the oxygen of carboxylic, sulfur of thiolic and nitrogen of the azomethine group. The X-ray data and ESR spectra specify a distorted square pyramidal environment around Cu(II) ion. (C) 2018 Elsevier B.V. All rights reserved.