Person: GAZİOĞLU, IŞIL
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Publication Metadata only Effect of roasting on antioxidant and anticholinesterase capacities of coffee(2014-01-01) Yilmaz, Pelin Koseoglu; Hacibekiroglu, IŞIL; Kolak, Ufuk; GAZİOĞLU, IŞILThe aim of the study was to investigate the effect of the roasting degree on total phenolic and flavonoid contents, antioxidant and anticholinesterase activities of the hexane, acetone, ethanol and water extracts of coffee. The antioxidant capacity of the water extracts prepared according to the brewing procedure of Turkish coffee was measured for the first time by 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging and cupric ion reducing antioxidant capacity (CUPRAC) assays. The in vitro anticholinesterase activity of the coffee extracts and caffeine was determined for the first time. Water extracts of the coffee samples exhibited the highest 2,2--azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) cation radical scavenging, DPPH free radical scavenging and CUPRAC effects. The hexane extract of coffee roasted for 25 min showed the highest acetylcholinesterase inhibitory activity among the tested extracts. Caffeine, which is known to have therapeutic effect against Alzheimer-s disease, was found to possess almost the same anticholinesterase activity as galanthamine. The roasting degree had an irregular effect on the antioxidant and anticholinesterase activities of the coffee extracts. The caffeine contents in extracts of coffee roasted for 25 min, which had strong anticholinesterase effect, were determined by HPLC, and the water extract was found to possess the highest caffeine content.Publication Open Access Triterpenoids and steroids isolated from Anatolian Capparis ovata and their activity on the expression of inflammatory cytokines(2020-01-01T00:00:00Z) GAZİOĞLU, IŞIL; Semen, Sevcan; Acar, Ozden Ozgun; KOLAK, Ufuk; Sen, Alaattin; TOPÇU, GÜLAÇTI; GAZİOĞLU, IŞIL; TOPÇU, GÜLAÇTIContext: Capparis L. (Capparaceae) is grown worldwide. Caper has been used in traditional medicine to treat various diseases including rheumatism, kidney, liver, stomach, as well as headache and toothache. Objective: To isolate and elucidate of the secondary metabolites of the C. ovata extracts which are responsible for their anti-inflammatory activities. Materials and methods: Buds, fruits, flowers, leaves and stems of C. ovata Desf. was dried, cut to pieces, then ground separately. From their dichloromethane/hexane (1:1) extracts, eight compounds were isolated and their structures were elucidated by NMR, mass spectroscopic techniques. The effects of compounds on the expression of inflammatory cytokines in SH-SY5Y cell lines were examined by qRT-PCR ranging from 4 to 96 mM. Cell viability was expressed as a percentage of the control, untreated cells. Results: This is a first report on isolation of triterpenoids and steroids from C. ovata with anti-inflammatory activity. One new triterpenoid ester olean-12-en-3b,28-diol, 3b-pentacosanoate (1) and two new natural steroids 5a,6a-epoxycholestan-3b-ol (5) and 5b,6b-epoxycholestan-3b-ol (6) were elucidated besides known compounds; oleanolic acid (2), ursolic acid (3), b-sitosterol (4), stigmast-5,22-dien-3b-myristate (7) and bismethyl-octylphthalate (8). mRNA expression levels as EC10 of all the tested seven genes were decreased, particularly CXCL9 (19.36-fold), CXCL10 (8.14-fold), and TNF (18.69) by the treatment of 26 mM of compound 1 on SH-SY5Y cells. Discussion and conclusions: Triterpenoids and steroids isolated from C. ovata were found to be moderate-strong anti-inflammatory compounds. Particularly, compounds 1 and 3 were found to be promising therapeutic agents in the treatment of inflammatory and autoimmune diseases.Publication Open Access An HPLC Method for the Determination of Moxifloxacin in Breast Milk by Fluorimetric Detection with Precolumn Derivatization(2017-03-01) Tekkeli, S. E. Kepekci; GAZIOGLU, IŞIL; KIZILTAS, M. V.; TEKKELİ, ŞERİFE EVRİM; GAZİOĞLU, IŞILA new, sensitive, and selective high-performance liquid chromatography (HPLC) method with fluorimetric detection was developed for the determination of moxifloxacin (MOX) in human breast milk. MOX was precolumn derivatized with fluorescamine; the fluorescent derivative was separated on an RP C18 column using a mobile phase composed of acetonitrile-10 mM orthophosphoric acid by isocratic elution with flow rate of 0.5 mL min(-1). The method was based on the measurement of the derivative using fluorescence detection at 481 nm with excitation at 351 nm. The calibration curve was linear over the range of 1-40 mu g mL(-1). Limit of detection (LOD) and limit of quantitation (LOQ) were found to be 0.3 and 1 mu g mL(-1), respectively. Intra-day and interday repeatabilities were less than 3.15%.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 Biological activities and phenolic-flavonoid contents of bilberry extracts(2012-12-01T00:00:00Z) Hacibekiroǧlu, IŞIL; KOLAK, Ufuk; GAZİOĞLU, IŞILPublication 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 Open Access Design, synthesis and docking study of novel coumarin ligands as potential selective acetylcholinesterase inhibitors(2017-01-01) Sonmez, Fatih; KURT, Belma Zengin; Gazioglu, IŞIL; BASILE, Livia; Dag, AYDAN; CAPPELLO, Valentina; GINEX, Tiziana; Kucukislamoglu, Mustafa; GUCCIONE, Salvatore; ZENGİN KURT, BELMA; GAZİOĞLU, IŞIL; DAĞ, AYDANNew coumaryl-thiazole derivatives with the acetamide moiety as a linker between the alkyl chains and/or the heterocycle nucleus were synthesized and in vitro tested as acetylcholinesterase (AChE) inhibitors. 2-(diethylamino)-N-(4-(2-oxo-2H-chromen-3-yl)thiazol-2-yl)acetamide (6c, IC50 value of 43 nM) was the best AChE inhibitor with a selectivity index of 4151.16 over BuChE. Kinetic study of AChE inhibition revealed that 6c was a mixed-type inhibitor. Moreover, the result of H4IIE hepatoma cell toxicity assay for 6c showed negligible cell death. Molecular docking studies were also carried out to clarify the inhibition mode of the more active compounds. Best pose of compound 6c is positioned into the active site with the coumarin ring wedged between the residues of the CAS and catalytic triad of AChE. In addition, the coumarin ring is anchored into the gorge of the enzyme by H-bond with Tyr130.Publication Metadata only Comparison of antioxidant, anticholinesterase, and antidiabetic activities of three curcuminoids isolated from Curcuma longa L.(2017-01-01) Kalaycıoğlu, Zeynep; Gazioglu, IŞIL; Erim, F. Bedia; GAZİOĞLU, IŞILAntioxidant, anticholinesterase and antidiabetic activities of three curcuminoids isolated from the Curcuma longa were simultaneously tested and compared in this study. The highest antioxidant power was detected for curcumin with the applied methods. The drug potentials of curcuminoids for Alzheimer-s disease were controlled. Bisdemethoxycurcumin (BDMC) showed substantial inhibitory activity. The activity of demethoxycurcumin (DMC) followed BDMC, whereas curcumin showed very little acetylcholinesterase inhibition activity. Antidiabetic activity of curcuminoids was evaluated by their -glucosidase inhibitory activities. All curcuminoids show activities with decreasing order as BDMC>curcumin>DMC. The significant activities of BDMC compared to its isomers and examination of chemical structures of isomers might be a starting point in designing new drugs for Alzheimer-s and Diabetes Mellitus.Publication Metadata only High performance liquid chromatographic analysis of lercanidipine in human breast milk(2019-01-01) Tekkeli, Evrim Kepekci; GAZİOĞLU, IŞIL; TIRIS, GİZEM; Onal, Cem; TEKKELİ, ŞERİFE EVRİM; GAZİOĞLU, IŞIL; TIRIS, GİZEMA simple, rapid, precise and accurate isocratic reversed phase HPLC method was developed and validated for the determination of lercanidipine hydrochloride in pharmaceutical tablets and spiked human breast milk. The chromatographic separation was achieved on C18 (250x4.6 mmx5 mu m) column using a mobile phase consisting of acetonitrile and phospate buffer (pH=4) (55:45, v/v) at a flow rate of 1.1 mL/min and UV detection at 237 nm. The linearity of the proposed method was investigated in the range of 1.0-40 mu g/mL (r(2)=0.9990). The method was validated in terms of accuracy, precision, reproducibility, specificity, robustness, and detection and quantification limits, in accordance with ICH guidelines. The proposed method is found as suitable for routine quantification of lercanidipine in human breast milk.Publication Metadata only Antioxidant and anticholinesterase activities of eleven edible plants(2011-03-01T00:00:00Z) Boga, Mehmet; Hacibekiroglu, IŞIL; Kolak, Ufuk; GAZİOĞLU, IŞILObjective: The antioxidant potential and anticholinesterase activity of eleven edible plants were investigated.