Person: ZENGİN KURT, BELMA
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Publication Metadata only Preparation and in vitro evaluation of 5-flourouracil loaded magnetite-zeolite nanocomposite (5-FU-MZNC) for cancer drug delivery applications(2016-02-01) Sagir, Tugba; Huysal, Merve; Durmus, ZEHRA; Kurt, BELMA; Senel, Mehmet; Isik, Sevim; ZENGİN KURT, BELMAIn this work, super paramagnetic magnetite nanoparticles were synthesized onto/into zeolite, then loaded with anti-cancer drug 5-fluorouracil (5-FU). The physical properties of the prepared nanocomposite and drug loaded nanocomposite were characterized using different techniques. The drug loading and releasing behavior of the magnetic nanocarrier was investigated and the drug-loaded nanoparticles exhibited a sustained release of drug without any burst release phenomenon. Furthermore, 5-FU loaded MZNC were evaluated for its biological characteristics. The functional 5-FU-MZNC has been triggered intra-cellular release of the cancer therapeutic agent 5-fluorouracil (5-FU). Cytotoxic effects of 5-FU loaded MZNC on human gastric carcinoma (AGS) cells were determined by real time cell analysis and colorimetric WST-1 cell viability assay. Apoptosis of cells was further investigated by Annexin-V staining which indicates the loss of cell membrane integrity. According to our results, 5-FU-MZNC showed a concentration-dependent cell proliferation inhibitory function against AGS cells. Morphologic and apoptotic images were consistent with the cytotoxicity results. In conclusion, 5-FU loaded MZNC efficiently inhibit the proliferation of AGS cells in vitro through apoptotic mechanisms, and may be a beneficial agent against cancer, however further animal study is still required. (C) 2015 Elsevier Masson SAS. All rights reserved.Publication Metadata only Synthesis, antioxidant activity and SAR study of novel spiro-isatin-based Schiff bases(2018-12-01) Sönmez, Fatih; ZENGİN KURT, BELMA; Küçükislamoğlu, Mustafa; Avcı, Davut; GAZİOĞLU, IŞIL; Güneşli, Zuhal; ZENGİN KURT, BELMA; GAZİOĞLU, IŞILA new series of 21 Schiff bases of spiro-isatin was synthesized, and their DPPH, CUPRAC and ABTS cation radical scavenging abilities were investigated for antioxidant activity. The results showed that all the synthesized compounds exhibited antioxidant activity for each assay. 5 & x30d;-(2,3-Dihydroxybenzylideneamino)spiro[[1,3] dioxolane-2,3 & x30d;-indoline]-2 & x30d;-on (5c) (IC50 = 4.49 mu M, for DPPH; IC50 = 0.39 mu M, for ABTS(.+); and A(0.50) = 0.42 mu M, for CUPRAC) showed significantly better ABTS, CUPRAC and DPPH radical scavenging ability than quercetin (IC50 = 8.69 mu M, for DPPH; IC50 = 15.49 mu M, for ABTS(.+); and A(0.50) = 18.47 mu M, for CUPRAC), which is used as a standard. SAR study showed that the synthesized compounds had higher ABTS(.+) activity than DPPH and CUPRAC activities. Moreover, the compounds (5c and 5d), containing two hydroxyl groups, exhibited the highest antioxidant activities for all assays. Quantum chemical calculations were also carried out to support SAR results.Publication Metadata only Two New Co(II) Complexes of Picolinate: Synthesis, Crystal Structure, Spectral Characterization, -Glucosidase nhibition and TD/DFT Study(2019-07-01) Alturk, Suemeyye; Avci, Davut; Kurt, BELMA; Tamer, Omer; Basoglu, Adil; Sonmez, Fatih; Atalay, Yusuf; Dege, Necmi; ZENGİN KURT, BELMACo(II) complexes of 2-picolinic acid (picH) and 6-methylpyridine-2-carboxylic acid (6-MepicH) {[Co(pic)(2)2H(2)O], (1), [Co(6-Mepic)(pic)2H(2)O], (2)} were obtained and their structural and spectroscopic properties were investigated by XRD, FT-IR and UV-Vis spectroscopic techniques. The measurement of -glucosidase inhibition of the synthesized complex 2 was fulfilled by IC50 values. In order to provide further explanations about the electronic spectral properties, TD-DFT calculations in ethanol solvent and gas phase were carried out. HSEh1PBE/6-311G(d,p) level has been used to calculate the nonlinear optics (NLO) parameters and frontier molecular orbital (FMO) energies. The experimental refractive indexes and optical band gap energies for the Co(II) complexes have been obtained using FT-IR and UV-Vis spectra, respectively. Lastly, the molecular docking study of Co(II) complexes was carried out in order to demonstrate interactions between the synthesized complexes and target protein (the template structure S. cerevisiae isomaltase).Publication Metadata only Chitosan and carboxymethyl cellulose based magnetic nanocomposites for application of peroxidase purification(2017-03-01) Kurt, BELMA; Uckaya, FATİH; Durmus, ZEHRA; ZENGİN KURT, BELMA; UÇKAYA, FATİHRecently, protein purification methods have a very wide area of research. Many of these methods are both expensive and multi-stage methods, that are needed in specific equipment. In this study, biopolymer coated magnetic nanoparticles, carboxymethyl cellulose (CMC) and chitosan (CH) coated Fe3O4 (magnetite) nanocomposites, are used in a new purification process. The structure of the synthesized magnetic nanocomposites were characterized by Fourier transform infrared (FTIR) spectrometry, X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), thermogravimetric (TGA) analysis and zeta potential for surface charge of magnetic nanocomposites. Molecular weight and purification degree of peroxidase were estimated with SDS-PAGE. Peroxidase enzyme was purified a yield of 82.55% with carboxymethyl cellulose and 76.72% with chitosan using this method. (C) 2016 Elsevier B.V. All rights reserved.Publication Metadata only Novel metal complexes containing 6-methylpyridine-2-carboxylic acid as potent α-glucosidase inhibitor: synthesis, crystal structures, DFT calculations, and molecular docking(2020-01-01T00:00:00Z) Avcı, Davut; Altürk, Sümeyye; Sönmez, Fatih; Tamer, Ömer; Başoğlu, Adil; Atalay, Yusuf; ZENGİN KURT, BELMA; Dege, Necmi; ZENGİN KURT, BELMAPublication Metadata only Novel Cu(II), Co(II) and Zn(II) metal complexes with mixed-ligand: Synthesis, crystal structure, α-glucosidase inhibition, DFT calculations, and molecular docking(2019-12-05) Avcı, D.; Altürk, Sümeyye; Sönmez, F.; Tamer, Ömer; Başoğlu, Adil; Atalay, Y.; Kurt, Belma; Dege, N.; ZENGİN KURT, BELMAPublication Metadata only Synthesis, anticholinesterase activity and molecular modeling study of novel carbamate-substituted thymol/carvacrol derivatives(2017-02-15) KURT, Belma Zengin; Gazioglu, IŞIL; Dag, AYDAN; Salmas, Ramin Ekhteiari; Kayik, Gulru; Durdagi, Serdar; Sonmez, Fatih; ZENGİN KURT, BELMA; GAZİOĞLU, IŞIL; DAĞ, AYDANNew thymol and carvacrol derivatives with the carbamate moiety were synthesized and their inhibitory effects on acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) were evaluated. 5-isopropyl-2-methylphenyl(3-fluorophenyl)carbamate (29) was found to be the most potent AChE inhibitor with IC50 values of 2.22 mu M, and 5-isopropyl-2-methylphenyl (4-fluorophenyl)carbamate (30) exhibited the strongest inhibition against BuChE with IC50 value of 0.02 mu M. Additionally, the result of H4IIE hepatoma cell toxicity assay for compounds 18, 20, 29, 30 and 35 showed negligible cell death at 0.07-10 mu M. Moreover in order to better understand the inhibitory profiles of these molecules, molecular modeling studies were applied. Binding poses of studied compounds at the binding pockets of AChE and BuChE targets were determined. Predicted binding energies of these compounds as well as structural and dynamical profiles of molecules at the target sites were estimated using induced fit docking (IFD) algorithms and post-processing molecular dynamics (MD) simulations methods (i.e., Molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) approaches). (C) 2016 Elsevier Ltd. All rights reserved.Publication Metadata only Preparation and characterization of platinum (Pt) and palladium (Pd) nanoparticle decorated graphene sheets and their utilization for the elimination of basic fuchsin and indigo carmine dyes(2016-01-01) Kurt, BELMA; Durmus, ZEHRA; Durmus, Ali; ZENGİN KURT, BELMAIn this study, graphene nano sheets, prepared with chemical oxidation and reduction routes via modified-Hummer method, were successfully decorated with platinum (Pt) and palladium (Pd) nanoparticles. Structural and morphological features of resulted graphene-metal nanocomposites were characterized with FT-IR, XRD, SEM and TEM methods. Anti-oxidant activity (AOA) values of nanocomposites were determined. The IC50 values of Pt-graphene and Pd-graphene nanocomposites were found to be 46.1 and 90.2 mg/mL, respectively based on the ABTS method and 80.2 and 143.7 mg/mL according to the DPPH method. It was found that the graphene-metal nanocomposites exhibited superior free radical scavenging activity compared to several types of noble metal nano particles although the nanocomposites consist of much lower amount of active metal sites than the nano-crystalline metal powders. It was consequently reported that the graphene-metal nanocomposites could be successfully used for the photocatalytic elimination of fuchsin and indigo carmine dyes under light irradiation. (C) 2015 Elsevier Masson SAS. All rights reserved.Publication Metadata only A new series of asymmetric bis-isatin derivatives containing urea/thiourea moiety: Preparation, spectroscopic elucidation, antioxidant properties and theoretical calculations(2021-09-05T00:00:00Z) YAKAN, Hasan; Serdar ÇAVUŞ, M.; KURT, BELMA; MUĞLU, Halit; SÖNMEZ, Fatih; GÜZEL, Emre; ZENGİN KURT, BELMA© 2021 Elsevier B.V.In the present study, design, synthesis, characterization, and investigation of antioxidant properties of novel asymmetric bis-isatin derivatives (1-8) containing urea/thiourea moiety are reported for the first time. FT-IR, 1H-NMR, and 13C-NMR spectroscopic methods and elemental analysis were used to elucidate the structures of the synthesized compounds. Their CUPRAC and ABTS cation radical scavenging abilities were investigated for antioxidant activity. The bis-isatins containing urea moiety (compounds 1-4) did not show ABTS activity, while those containing the thiourea moiety (compounds 5-8) showed moderate ABTS activity. Besides, all bis-isatins were observed to exhibit CUPRAC activity at a low micromolar level The 1-(5-chloro-2-oxoindolin-3-ylidene)-5-(2-oxoindolin-3-ylidene)thiocarbonohydrazide (compound 5) showed the highest ABTS activity with IC50 value of 18.44 µM; on the other hand, the 1-(5-chloro-2-oxoindolin-3-ylidene)-5-(5-methoxy-2-oxoindolin-3-ylidene)carbonohydrazide (compound 2) had the strongest CUPRAC activity with A0.50 value of 0.600 µM. Both spectroscopic and antioxidant properties of the compounds were examined computationally, and the structure-activity relationship was investigated theoretically by comparing with experimental data. The ground state geometries and chemical reactivity parameters of the compounds were calculated using the B3LYP hybrid functional with 6-311++g(2d,2p) and 6-31g(d) basis sets. After determining the local electron affinity of the compounds, the Laplacian bond order and intrinsic bond strength indexes (independent gradient model-δgIGMH and IBSIIGMH descriptors based on Hirshfeld approach) of hydrogen bonds at possible reactive sites were calculated and associated with the antioxidant properties of the compounds.Publication Metadata only A novel series of M(II) complexes of 6-methylpyridine-2-carboxylic acid with 4(5)methylimidazole: Synthesis, crystal structures, α-glucosidase activity, density functional theory calculations and molecular docking(2019-07-01) Avcı, Davut; Altürk, Sümeyye; Sönmez, Fatih; Tamer, Ömer; Başoğlu, Adil; Atalay, Yusuf; Zengin Kurt, Belma; Dege, Necmi; ZENGİN KURT, BELMA