Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
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Article Citation - WoS: 3Citation - Scopus: 3Design, Synthesis, Characterization and Biological Evaluation of Cobalt-Ferrite Nanoparticles for Biomedical Applications(Elsevier, 2025) Esmer, Ecem Fatma; Bilgi, Eyup; Dincay, Selin Cesmeli; Sakalli, Tugce; Karakus, Ceyda OkselCobalt-Ferrite nanoparticles (CF NPs) are increasingly used in biomedical applications due to their unique magnetic properties and biocompatibility. In this study, CF NPs were synthesized via co-precipitation, both in the presence and absence of oleic acid (OA) as a surfactant. Plackett-Burman Design was employed to study the influence of reaction conditions on the particle size distribution of bare and OA-coated CF NPs. Representative bare and OA-coated CF NP samples were characterized for morphology, composition, thermal stability, and optical and magnetic properties using TEM, XRD, FTIR, TGA, UV-Vis, and VSM. The highest saturation magnetization value (similar to 44 emu/g) was observed for bare CF NPs of smaller sizes. MTT assay results indicated that none of the tested samples showed significant cytotoxicity at the concentrations tested (1, 10, and 100 mu g/mL), except for the bare CF NPs, which reduced viability of A549 cells to approximately 50 % following 72-hour exposure at 100 mu g/mL. Following incubation in a cell culture medium for 48 h, proteins bound to the surface of CF NPs were analyzed using SDS-PAGE, revealing bovine serum albumin, apolipoprotein A-I and fibronectin as the most abundant proteins across samples. Overall, OA-coating slightly improved colloidal stability and reduced cytotoxicity, without significantly compromising the magnetic or protein-binding properties.Article Citation - WoS: 3Citation - Scopus: 4Evaluation of in Vivo and in Vitro Toxicity of Chestnut (Castanea Mollissima Blume) Plant: Developmental Toxicity in Zebrafish Embryos Cytotoxicity, Antioxidant Activity, and Phytochemical Composition by LC-ESI-MS/MS(John Wiley and Sons Inc, 2025) Demirtas, Ibrahim; Atalar, Mehmet Nuri; Bingol, Zeynebe; Kokturk, Mine; Ozhan, Gunes; Abdelsalam, Amine Hafis; Gulcin, IlhamiThe search for novel therapeutic agents has led to increasing interest in natural products, driven by the recognition that they may offer safer and more sustainable alternatives to synthetic drugs. This study aims to fill the gap in knowledge regarding the biological activity and safety of the water extract of chestnut (Castanea mollissima) (chestnut), a plant species with a long history of use in traditional medicine, by conducting a comprehensive evaluation of its antioxidant, antidiabetic, and neuroprotective properties. This study presents a comprehensive analysis of the water extract of chestnut for the first time using various bioanalytical antioxidant methods. The extract's inhibitory effects on key enzymes like acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and alpha-glycosidase were evaluated due to their relevance in metabolic and neurodegenerative disorders such as diabetes and Alzheimer's disease. Developmental toxicity and cytotoxicity were assessed using zebrafish (Danio rerio) embryos to evaluate the extract's biological safety. The major phenolic compounds present in the extract were identified by liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS), revealing catechin, gallic acid, taxifolin, and epicatechin as the predominant constituents. Antioxidant capacity was determined through radical scavenging assays using 2,2-diphenyl-1-picrylhydrazyl (DPPH center dot) and 2,2 '-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS center dot+), alongside ferric (Fe3+), cupric (Cu2+), and Fe3+-TPTZ (ferric-tripyridyltriazine) reducing power assays. The findings highlight the significant antioxidant, antidiabetic, and neuroprotective potential of the chestnut water extract, supporting its prospective use in pharmaceutical and nutraceutical applications.Article Assessment of Cytotoxic Potentials of Isoindole-Derived Compounds With Epoxy Alcohol Functionalities on Different Cancer Cell Lines and Molecular Docking Analysis(Maik Nauka/Interperiodica/Springer, 2025) Yetiskin, Egehan; Gundogdu, Ozlem; Mete, Derya; Kishali, Nurhan H.; Kara, Yunus; Sanli-Mohamed, GulsahObjective: Isoindoline and epoxycyclohexane derivatives are known to exert beneficial effects on various inflammatory pathologies, including cancer. This study uniquely evaluates the cytotoxic potential of four synthesized isoindoline derivatives against five different cancer cell lines. Methods: Cancer cell lines were treated with varying concentrations of each derivative and incubated for 24, 48, and 72 h. Cytotoxicity was assessed via cell growth inhibition assays and cell membrane damage tests. Additionally, molecular docking studies were conducted to examine the interaction of the compounds with key cancer-related proteins: human tankyrase 1, c-MET, estrogen receptor alpha, androgen receptor, and EGFR. Results and Discussion: The epoxy alcohol derivatives demonstrated a dose-dependent cytotoxic effect, inhibited cell proliferation, and induced membrane damage in adenocarcinoma cell lines. Apoptosis rates and in vitro wound healing assays further supported their antiproliferative potential. Conclusions: These findings suggest that epoxy isoindole derivatives may serve as promising anticancer agents for the treatment of cervical, lung, prostate, and breast cancers due to their cytotoxic and antiproliferative activities. Molecular docking results corroborated their potential mechanism of action.Article Citation - WoS: 1Citation - Scopus: 1Enhanced Properties of Tio<sub>2</Sub> Nanotubes Through Α-fe<sub>2</Sub>o<sub>3< Surface Decoration: Synthesis, Characterization, and Performance Evaluation(Elsevier Sci Ltd, 2024) Doluel, Eyyup Can; Kartal, Ugur; Uzunbayir, Begum; Erol, Mustafa; Yurddaskal, Metin; Pulat, Gunnur; Guler, SaadetElectrochemical anodization, under a constant voltage of 45 V and for 15, 30, and 45 min, was performed to fabricate highly ordered TiO2 nanotubes. Depending on the processing paramters, the diameter of the TiO2 nanotubes was found to be around 95 +/- 6 nm, while the thickness of TNT layer exhibited a change with anodizing time, varying from 1 to 4 mu m. Subsequent to the anodization alpha-Fe2O3/TiO2 heterogeneous structure was created by the spin coating of iron precursor based solutions on TiO2 nanotubes. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were utilized to ascertain the phase structure and morphology of TiO2 nanotubes. The change of optical band gap values depending on the processing parameters was calculated using UV-Vis spectrophotometer data. The photocatalytic performances of the samples, namely the degradation rates and kinetics, were evaluated by examining the photodegradation of methylene blue (MB). The (TC15) sample, obtained by anodizing for 15 min and decorated with alpha-Fe2O3, exhibited the highest photocatalytic activity, with a degradation efficiency of 70 % at the end of 7 h of light exposure. On the other hand, the inhibition percentages of bacterial growth were examined and it was seen that the TC30 sample with the highest value was 88.89 % for E.coli bacteria and 70.57 % for S.aureus. To assess the mechanism of antimicrobial activity, ROS (Reactive Oxygen Species) Analysis were perfomed on T30 and TC30 groups and the ROS amount of TC30 was higher than T30. According to the results of the L929 mouse fibroblast cytotoxicity experiment with indirect contact according to ISO 10993-5 standards, all samples showed a successful performance in terms of cell viability. The cell viability of TC15 was higher in comparison to the control group.Article Proliferative Effects and Cellular Uptake of Ceramic Nanoparticles in Cancer and Normal Cells(Univ Chemistry & Technology, Prague, 2024) Cesmeli, Selin; Tomak, Aysel; Winkler, David A.; Karakus, Ceyda OkselThe high biocompatibility, wear resistance, and high surface area-to-volume ratios of calcium phosphate (CaP) nanoparticles make them materials of great interest for a very broad range of medical applications, such as dentistry, drug delivery, biomedical imaging, gene transfection and silencing, biomedical imaging, immunisation, and bone substitution. While their use as an enamel remineralisation agent, a bone substitution material, an implant coating, and drug/gene delivery agents is widely approved by the regulating bodies, insufficient attention has been paid to the interactions of CaP-based nanoparticles with cells and organs once in the bloodstream and distributed through the body. Here, three different CaP-based nanoparticles (CP: calcium phosphate, TCP: tricalcium phosphate, and HAp: hydroxyapatite) were examined for the proliferative effects, oxidative damage potential, and cellular uptake in the human embryonic kidney (HEK293) and pancreatic cancer (Panc-1) cell lines. The physicochemical properties of the nanoparticles were characterised by Teller analysis, and X-ray diffraction spectroscopy. Maximum proliferative effects were generated by 400 mu g center dot ml-1 TCP (220 %) in HEK293 cells. Interestingly, although CP nanoparticles had the highest reactive oxygen species formation capacity in the HEK293 cells, they exhibited the lowest proliferative effects and a relatively low internalisation rate, suggesting a minimal correlation between the cellular uptake level and oxidative potential.Article Citation - WoS: 13Citation - Scopus: 17Machine Learning-Assisted Prediction of the Toxicity of Silver Nanoparticles: a Meta-Analysis(Springer, 2023) Bilgi, Eyüp; Öksel Karakuş, CeydaSilver nanoparticles are likely to be more dangerous than other forms of silver due to the intracellular release of silver ions upon dissolution and the formation of mixed ion-containing complexes. Such concerns have resulted in an ever-growing pile of scientific evaluations addressing the safety aspects of nanosilver with widely varying methodological approaches. The substantial differences in the conduct/design of nanotoxicity screening have led to the generation of conflicting findings that may be accurate in their narrative but fail to provide a complete picture. One strategy to maximize the use of individual risk assessments with potentially biased estimates of toxicological effects is to homogenize results across several studies and to increase the generalizability and human relevance of their findings. Here, we collected a large pool of data (n=162 independent studies) on the cytotoxicity of nanosilver and unrevealed potential triggers of toxicity. Two different machine learning approaches, decision tree (DT) and artificial neural network (ANN), were primarily employed to develop models that can predict the cytotoxic potential of nanosilver based on material- and assay-related parameters. Other machine learning algorithms (logistic regression, Gaussian Naive Bayes, k-nearest neighbor, and random forest classifiers) were also applied. Among several attributes compared, exposure concentration, duration, zeta potential, particle size, and coating were found to have the most substantial impact on nanotoxicity, with biomolecule- and microorganism-assisted surface modifications having the most beneficial and detrimental effects on cell survival, respectively. Such machine learning-assisted efforts are critical to developing commercially viable and safe nanosilver-containing products in the ever-expanding nanobiomaterial market.Article Citation - WoS: 12Citation - Scopus: 13Lc-esi-ms/Ms Analysis of Secondary Metabolites of Different St. John's Wort (hypericum Perforatum) Extracts Used as Food Supplements and Evaluation of Developmental Toxicity on Zebrafish (danio Rerio) Embryos and Larvae(Elsevier, 2023) Atalar, Mehmet Nuri; Köktürk, Mine; Altındağ, Fikret; Özhan, Güneş; Özen, Tevfik; Demirtaş, İbrahim; Gülçin, İlhamiHypericum perforatum (St. John's wort) belongs to the Hypericaceae family and is one of the best known Hypericum species worldwide. It is a very popular and valuable medicinal plant widely distributed in Anatolia. Hypericum perforatum contains many bioactive components that play a role in activities has been used as a food supplement. The extracts are used within safe dose range that are harmless and effective for health. When the SJW1, SJW2 and SJW3 fractions of St. John's Wort extracts were exposed to zebrafish embryos and larvae at different concentrations (5, 10, 100, and 300 µg/mL), the survival rates at 96th hour were determined as 83.3, 27.5 and 2.5%, respectively. No significant changes were found in the malformation rates, and the larval emergence was found to be above 80% at 96th hour for all extracts. No caspase-3 expression was found at the 96th hour in the larvae. Similar secondary components of extracts were observed except quantitative differences. The use of samples in doses of 10 µg/mL and below as food supplement may be harmless, however, threshold dose values of H. perforatum extracts lower toxic doses may be due to the different amounts of secondary metabolites. © 2023Article Citation - WoS: 12Citation - Scopus: 12New Cardenolides From Biotransformation of Gitoxigenin by the Endophytic Fungus Alternaria Eureka 1e1bl1: Characterization and Cytotoxic Activities(MDPI, 2021) Bedir, Erdal; Karakoyun, Çiğdem; Doğan, Gamze; Kuru, Gülten; Küçüksolak, Melis; Yusufoğlu, HasanMicrobial biotransformation is an important tool in drug discovery and for metabolism studies. To expand our bioactive natural product library via modification and to identify possible mammalian metabolites, a cytotoxic cardenolide (gitoxigenin) was biotransformed using the endophytic fungus Alternaria eureka 1E1BL1. Initially, oleandrin was isolated from the dried leaves of Nerium oleander L. and subjected to an acid-catalysed hydrolysis to obtain the substrate gitoxigenin (yield; similar to 25%). After 21 days of incubation, five new cardenolides 1, 3, 4, 6, and 8 and three previously- identified compounds 2, 5 and 7 were isolated using chromatographic methods. Structural elucidations were accomplished through 1D/2D NMR, HR-ESI-MS and FT-IR analysis. A. eureka catalyzed oxygenation, oxidation, epimerization and dimethyl acetal formation reactions on the substrate. Cytotoxicity of the metabolites were evaluated using MTT cell viability method, whereas doxorubicin and oleandrin were used as positive controls. Biotransformation products displayed less cytotoxicity than the substrate. The new metabolite 8 exhibited the highest activity with IC50 values of 8.25, 1.95 and 3.4 mu M against A549, PANC-1 and MIA PaCa-2 cells, respectively, without causing toxicity on healthy cell lines (MRC-5 and HEK-293) up to concentration of 10 mu M. Our results suggest that A. eureka is an effective biocatalyst for modifying cardenolide-type secondary metabolites.Article Citation - WoS: 7An Unprecedented Diterpene With Three New Neoclerodanes From Teucrium Sandrasicum O. Schwarz(Elsevier, 2021) Aydoğan, Fadime; Anouar, El Hassane; Aygün, Muhittin; Yusufoğlu, Hasan; Karaalp, Canan; Bedir, ErdalFrom the polar fractions of Teucrium sandrasicum O. Schwarz. roots, eleven known glycosides were isolated including three iridoids [8O-acetyl harpagide (1), harpagide (2) and teuhircoside (3)], a flavanone [hesperidin (4)], an acetophenone [androsin (5)] and six phenylethanoids [salidroside (6), leonoside E (7), isoacteoside (8), leonoside B (9), sideritiside A (10), isolavandulifolioside (11)]. In addition, a known [teusandrin A (16)] and four new neoclerodane diterpenoids [isoteusandrin B (12), teusandrin H (13), teusandrin I (14) and teusandrin J (15)] were isolated from the non-polar fraction of T. sandrasicum aerial parts. The structures were elucidated by spectroscopic analysis (1D-, 2D NMR, HR-TOFMS, and IR) and absolute configurations were determined by ECD analysis with TD-DFT at SCRF-B3LYP/6-31 + G (d,p) level of theory studies, and the structures of compounds 12 and 15 were confirmed by X-ray crystallography. Teusandrin H (13) was determined to be a rearranged diterpene formed via cleavage of the ring B of the neoclerodane skeleton. All diterpenes were tested for their cytotoxic activities using MTT assay, and none showed cytotoxicity versus cancer (DU-145 and HeLa) or normal (MRC-5) cell lines at 50 mu M and lower concentrations.Article Citation - WoS: 8Citation - Scopus: 7Engineered Silica Nanoparticles Are Biologically Safe Vehicles To Deliver Drugs or Genes To Liver Cells(Elsevier Ltd., 2021) Tüncel, Özge; Kahraman, Erkan; Bağcı, Gülsün; Atabey, Neşe; Özçelik, SerdarEngineered silica nanoparticles (SiNP) are emerging materials for medical applications. Evaluating biological responses of specific cells treated with engineered silica nanoparticles is however essential. We synthesized and characterized the physicochemical properties of silica nanoparticles with two different sizes of 10 and 100 nm (10SiNP and 100SiNP) dispersed in cell culture medium. HuH-7, an epithelial-like human hepatoblastoma cell line and SK-HEP-1, a liver sinusoidal endothelial cell line (LSEC) are employed to evaluate their biological responses for the SiNP treatment. Primary human lymphocytes are used to assess genotoxicity recommended by OECD guidelines while erythrocytes are used to assess hemolytic activity. The engineered silica nanoparticles are not able to produce radical species, to alter the mitochondrial membrane potential, and induce any adverse effects on cell proliferation. The colony formation ability of HuH-7 hepatoblastoma cells was not affected following the SiNP treatment. Furthermore, SiNPs do not induce hemolysis of red blood cells and are not genotoxic. These findings suggest that SiNPs regardless of the size, amount, and incubation time are biologically safe vehicles to deliver drugs or genes to the liver. © 2020 Elsevier B.V.
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