Sürdürülebilir Kalkınma Amaçları
Yazarlar
- Gul, Muhammet(102)
- Güler, Ömer(69)
- Akkurt, Nevzat(68)
- Tekin, H.O.(52)
- ALMisned, Ghada(49)
- Yucesan, Melih(49)
- Celik, Erkan(45)
- Zengin, Gokhan(40)
- Serdar, Osman(39)
- Kocabaş, Mehmet(37)
- Aslan, Naim(31)
- Baskonus, Haci Mehmet(31)
- Bulut, Hasan(31)
- Mete, Suleyman(31)
- Paksoy, Mehmet Yavuz(30)
- Kök, Mediha(27)
- Ince, Muharrem(26)
- Yildirim, Ozal(26)
- Özkul, İskender(26)
- Sulaiman, Tukur Abdulkadir(25)
- Topal, Murat(25)
- Guler, Omer(24)
- Serin, Faruk(23)
- Benzer, Fulya(22)
- Erten, Fusun(22)
- Alataş, Mevlüt(21)
- Güler, Seval Hale(21)
- Baykal, Duygu Sen(20)
- Taşgın, Yahya(20)
- Kutlu, Banu(19)
- Onat, Onur(19)
- Sahin, Kazim(19)
- Tanyol, Mehtap(19)
- Torğut, Gülben(19)
- Yildirim, Numan(19)
- Kahraman, Gökhan(18)
- Orhan, Cemal(18)
- Say, Yakup(18)
- Susam, Selim Orhun(18)
- Utku, Anıl(18)
Yayınlar
- MakaleYalnız künye2020Scopus SJRQ1Evaluation of the radiation shielding capabilities of the Na2B4O7–SiO2–MoO3-Dy2O3 glass quaternary using Geant4 simulation code and Phy-X/PSD database
Aşkın, A.
The important gamma and neutron radiation shielding parameters of the Dy3+ doped (65-x)Na2B4O7–15SiO2–20MoO3-xDy2O3 (x = 0, 5, 10, 15, 20 mol%) glass quaternary system were investigated to provide decisive information for their application in radiation environment. Gamma and neutron attenuation properties of the glass systems studied here were evaluated in terms of the mass attenuation coefficient (μm), transmission fraction (TF), half value layer (HVL), mean free path (MFP), effective atomic number (Zeff), exposure buildup factors (EBF) and fast neutron removal cross-section (∑R) parameters. Investigation of the each aforementioned parameter was performed thanks to the utilization of Monte Carlo simulations along with the Phy-X/PSD database. The photon attenuation characteristics were evaluated for gamma ray energies varying between 0.284 and 5.0 MeV. This study indicated that increase of the Dy2O3 content from 0% to 20% mole, enhances the gamma shielding capability due to the increase of the parameters μm and Zeff. In this study it was also observed that ∑R increases from 0.099 to 0.107 cm−1 as the molar fraction of Dy2O3 increases.
AtıfScopus75WoS74OpenAlex82
İncele - MakaleYalnız künye2020Scopus SJRQ2Optimization of open channels using particle swarm optimization algorithm
Saplioglu, Kemal; Ozturk, Tulay Sugra Kucukerdem; Acar, Ramazan
Due to recent increasing water demand, planning and projecting of water resources has resulted in increased costs. There-fore, it is important to obtain optimum results in project planning. In this study, dimensioning of open channels used espe-cially for irrigation purposes has been studied using a particle swarm optimization algorithm to investigate optimum base width, channel height, and slope angles. The results are summarized in graphs and tables. In the study, it was found that the optimum slope angle varied between 0. 200. 45. Furthermore, it was found that increasing the slope angle significant-ly increased costs. Finally, the increase in flow increases costs but the rate of increase diminishes.
AtıfScopus6WoS6OpenAlex9İncele - MakaleYalnız künye2020Scopus SJRQ3Potential anesthetic properties of bay leaf (Laurus nobilis) essential oil compared with 2-phenoxyethanol on blue dolphin cichlid, cyrtocara moorii
Kizak, Volkan; Can, Erkan; Seyhaneyildiz Can, Şafak
The efficacy of Bay leaf (Laurus nobilis) essential oil (LnEO) as a herbal anesthetic agent was evaluated with 2-Phenoxyethanol (2-PE) in Blue Dolphin Cichlid, Cyrtocara moorii. Fish were exposed to different anesthetic concentrations and the lowest effective concentrations (LECs) were determined according to deep anesthesia (AD<3 min) and full recovery (RF<5 min) times. LnEO showed anesthetic properties, and all applied concentrations of both agents induced AD in C. moorii. The LECs of LnEO and 2-PE for C. moorii were determined as 800 µl L-1 (AD; RF → 183 ± 6.3 s; 191 ± 2.6 s) and 600 µl L-1 (AD; RF → 171 ± 3.2 s; 239 ± 4.9 s), respectively. Significant differences were found between anesthetic agents in terms of deep anesthesia and full recovery times for the same concentrations (p<0.05). Induction and recovery times decreased with increasing in LnEO concentrations. On the other hand, anesthesia times were decreased with increasing of 2-PE concentrations, while recovery times increased. Induction and recovery times for LnEO were significantly dependent on concentrations and positive relationships were recorded between AD and RF, whereas the relationship was negative in 2-PE. Bay leaf essential oil has not been used as an anesthetic agent in fish until now. Our results showed that LnEO was an effective anesthetic agent with some minor side effects on C. moorii.
AtıfScopus2OpenAlex2İncele - MakaleYalnız künye2020Scopus SJRQ1Assessment of occupational risks from human health and environmental perspectives: a new integrated approach and its application using fuzzy BWM and fuzzy MAIRCA
Gul, Muhammet; Ak, M. Fatih
Occupational safety issues encountered in the worksite environment are the issues that companies should consider in improving their operations with a view to human health and environmental awareness. Many methods with different rationales have been existed in the literature to prioritize hazards according to their risk levels and to mitigate their consequences. In this study, a new model is developed for occupational risk assessment by merging two well-known multi-criteria decision-making methods named best and worst method (BWM) and multi attribute ideal real comparative analysis (MAIRCA) under fuzzy environment. The proposed model differentiates from other similar models by three aspects. First, it considers severity of a hazard and its associated risk from the human and environmental riskiness perspectives. Secondly, it applies fuzzy BWM (F-BWM) to calculate the relative importance of three risk factors named as “probability, frequency and severity” of traditional Fine–Kinney method. Thirdly, it applies fuzzy MAIRCA (F-MAIRCA) to rank hazards according to their risk level using importance values obtained by F-BWM. To show applicability of the approach, a case study of risk assessment in a marble factory is fulfilled. Additionally, a number of validation studies including benchmarking analysis with fuzzy VIKOR and fuzzy TOPSIS methods; a sensitivity analysis by varying importance weights of risk factors are carried out to highlight the solidity of the proposed approach.
AtıfScopus80WoS70İncele - MakaleYalnız künye2020Scopus SJRQ1Teaching Shakespeare digitally: the Turkish experience
Öğütcü, Murat
Although teaching Shakespeare in Turkey naturally creates barriers of language, space and time, the use of digital humanities helped me to overcome these obstacles. My experiences at Hacettepe University, Ankara, Turkey, showed me that combining conventional methods of teaching Shakespeare in Turkey with digital tools helps to familiarise students with Shakespeare's plays both in the Early Modern English and Modern Turkish contexts. To motivate students to study Shakespeare's plays within and without the classroom environment, I used conventional methods like teacher-led assignments and methods including the use of social media and social projects which were then unconventional.
AtıfScopus4WoS3İncele - MakaleYalnız künye2020Scopus SJRQ1Mechanical, thermal, and morphological properties of powder coating waste reinforced acetal copolymer
Kismet, Yilmaz; Wagner, Manfred H.
The present study investigates the individual effects of three different thermosetting waste materials, used as fillers, on the mechanical, thermal and flow properties of acetal copolymers (POM). Different amounts ranging from 5% to 30% by weight of hydrolyzed powder coating recyclates were mixed as filler material in POM. The matrix and the fillers were first dry-mixed and then compounds were prepared through melt extrusion. The resulting compounds were cooled, granulated, and then standard tensile test bars were produced through use of an injection-molding machine. We investigated the mechanical and thermal properties of test specimens, and tensile strength, bending strength and impact strength were evaluated as a function of type and amount of filler material in the POM matrix. In addition, the change in melt flow index of POM/filler mixtures was determined, before and after extrusion. Furthermore, the morphology of the specimens was examined via electron microscopy. The results of this investigation are encouraging and present an innovative approach to reutilize hydrolyzed electrostatic powder coating wastes with thermoset structures as fillers in acetal copolymers.
AtıfScopus10WoS8OpenAlex13İncele - MakaleYalnız künye2020Scopus SJRQ1Geochemical characteristics of the adakite-like Dodurga Pluton (Central Pontides, N Turkey): implications for Middle Triassic continental arc magmatism in southern Black Sea region
Çimen, Okay
The tracing of Triassic arc magmatism is much-debated for a long time along the Sakarya Composite Terrane in Turkey and the southern Black Sea region. The Dodurga Pluton is located in the Central Pontides (N Turkey), one of the most complicated regions around the Black Sea region, and represents the first documented middle Triassic continental arc in the region. This pluton comprises of dacite porphyry and granodiorite, and displays calc-alkaline signatures, which is in agreement with arc-related and I-type magmas. The PM-normalized multi element and CN-normalized REE patterns are akin to volcanic arc granites, and characterized by LILEs and LREEs enrichments relative to HFSEs and HREEs coupled with negative Nb anomalies, which confirm derivation in a subduction-related tectonic setting. Moreover, the major and trace element systematics of the samples including higher Sr/Y ratios (22.93–101.36) and lower Yb contents (0.31–1.30 ppm) are consistent with those from adakitic melts compared to classical arc magmas. Therefore, this pluton also represents the first middle Triassic adakite-like magmatic occurrence in Turkey. Overall petrographic and geochemical signatures reported here indicate that the Dodurga Pluton might have been derived from a heterogeneous source, mixed by melts from subducted oceanic slab and lower continental crust in an active continental margin. Based on the Tethyan evolution in the Anatolian realm, three geodynamic scenarios are possible for its formation, and it could have been formed as a result of northward or southward-subduction of the Paleotethys Ocean or northward-subduction of the northern branch of Neotethys Ocean during the middle Triassic.
AtıfScopus8WoS8OpenAlex4İncele - MakaleAçık Erişim2020Scopus SJRQ1Evaluation of hospital disaster preparedness by a multi-criteria decision making approach: The case of Turkish hospitals
Ortiz-Barrios, Miguel; Gul, Muhammet; López-Meza, Pedro; Yucesan, Melih; Navarro-Jiménez, Eduardo
Considering the unexpected emergence of natural and man-made disasters over the world and Turkey, the importance of preparedness of hospitals, which are the first reference points for people to get healthcare services, becomes clear. Determining the level of disaster preparedness of hospitals is an important and necessary issue. This is because identifying hospitals with low level of preparedness is crucial for disaster preparedness planning. In this study, a hybrid fuzzy decision making model was proposed to evaluate the disaster preparedness of hospitals. This model was developed using fuzzy analytic hierarchy process (FAHP)-fuzzy decision making trial and evaluation laboratory (FDEMATEL)-technique for order preference by similarity to ideal solutions (TOPSIS) techniques and aimed to determine a ranking for hospital disaster preparedness. FAHP is used to determine weights of six main criteria (including hospital buildings, equipment, communication, transportation, personnel, flexibility) and a total of thirty-six sub-criteria regarding disaster preparedness. At the same time, FDEMATEL is applied to uncover the interdependence between criteria and sub-criteria. Finally, TOPSIS is used to obtain ranking of hospitals. To provide inputs for TOPSIS implementation, some key performance indicators are established and related data is gathered by the aid of experts from the assessed hospitals. A case study considering 4 hospitals from the Turkish healthcare sector was used to demonstrate the proposed approach. The results evidenced that Personnel is the most important factor (global weight = 0.280) when evaluating the hospital preparedness while Flexibility has the greatest prominence (c + r = 23.09).
AtıfScopus87WoS69OpenAlex97
İncele - MakaleAçık Erişim2020Scopus SJRQ11D-CADCapsNet: One dimensional deep capsule networks for coronary artery disease detection using ECG signals
Butun, Ertan; Yildirim, Ozal; Talo, Muhammed; Tan, Ru-San; Rajendra Acharya, U.
Purpose: Cardiovascular disease (CVD) is a leading cause of death globally. Electrocardiogram (ECG), which records the electrical activity of the heart, has been used for the diagnosis of CVD. The automated and robust detection of CVD from ECG signals plays a significant role for early and accurate clinical diagnosis. The purpose of this study is to provide automated detection of coronary artery disease (CAD) from ECG signals using capsule networks (CapsNet). Methods: Deep learning-based approaches have become increasingly popular in computer aided diagnosis systems. Capsule networks are one of the new promising approaches in the field of deep learning. In this study, we used 1D version of CapsNet for the automated detection of coronary artery disease (CAD) on two second (95,300) and five second-long (38,120) ECG segments. These segments are obtained from 40 normal and 7 CAD subjects. In the experimental studies, 5-fold cross validation technique is employed to evaluate performance of the model. Results: The proposed model, which is named as 1D-CADCapsNet, yielded a promising 5-fold diagnosis accuracy of 99.44% and 98.62% for two- and five-second ECG signal groups, respectively. We have obtained the highest performance results using 2 s ECG segment than the state-of-art studies reported in the literature. Conclusions: 1D-CADCapsNet model automatically learns the pertinent representations from raw ECG data without using any hand-crafted technique and can be used as a fast and accurate diagnostic tool to help cardiologists.
AtıfScopus100OpenAlex96İncele - MakaleYalnız künye2020Scopus SJRQ2Analytical and finite element solutions of continuous contact problem in functionally graded layer
Kaya, Yusuf; Polat, Alper; Özşahin, Talat Şükrü
In this study, we solve the continuous contact problem of two layers with different material properties, loaded with two rigid flat blocks and resting on a rigid plane, by analytical and finite element methods. All surfaces are assumed to be frictionless. The upper layer is the functionally graded layer (FG), the height h1, the underlying layer is homogeneous, and the height is h2. It is assumed that the FG layer is isotropic and that the shear modulus and density change exponentially. The FG layer is loaded by means of two rigid flat blocks whose external loads are Q and P (per unit thickness in z direction). In the analytical solution of the problem, stress and displacement expressions are substituted in the boundary conditions and the problem is demoted to singular integral equations where the contact stresses are the unknown functions. These singular integral equations are solved numerically using the Gauss–Chebyshev integration formulas. Two-dimensional finite element analysis of the problem is performed using the ANSYS package program. The analyses are performed for different shear modulus ratios (μ2/μ-h1), distances between the blocks ((c − b)/h1) and inhomogeneity parameters (βh1). The contact stresses under the blocks, the normal stresses (σy) between interfaces of the FG layer and the homogeneous layer and between the homogeneous layer and rigid plane are also measured. In addition, the initial separation load and the initial separation distances (χcr, λcr) of the FG layer and homogeneous layer are determined. The results are presented comparatively as graphs and tables.
AtıfScopus18WoS19OpenAlex14İncele - KitapYalnız künye2020Computational intelligence and soft computing applications in healthcare management science
Gul, Muhammet; Celik, Erkan; Mete, Suleyman; Serin, Faruk
In today's modernized world, the field of healthcare has seen significant practical innovations with the implementation of computational intelligence approaches and soft computing methods. These two concepts present various solutions to complex scientific problems and imperfect data issues. This has made both very popular in the medical profession. There are still various areas to be studied and improved by these two schemes as healthcare practices continue to develop.
AtıfOpenAlex7İncele - MakaleYayıncıda açık erişim2020Scopus SJRQ2Phytoremediaton of priority substances (Pb and Ni) by Phragmites australis exposed to poultry slaughterhouse wastewater
Topal, Murat; Arslan Topal, E. Işıl
The aim of the work was to evaluate the ability of Phragmites australis to uptake lead and nickel from the stream taking the treated poultry slaughterhouse wastewater (PSW). Pb and Ni concentrations, which are the priority substances of the water frame directive, were detected separately at the root, stem and leaf of P. australis at 50 m and 100 m from the downstream of discharge point. The uptake of Pb and Ni by P. australis followed the order of root > leaf > stem. The Ni uptake was higher than Pb uptake in P. australis exposed to poultry wastewater. As a result, P. australis exposed to PSW were found to have the ability to uptake Pb and Ni. It has been determined that P. australis can be used for removal and phytoremediation of Pb and Ni metals from PSWs.
AtıfScopus13WoS12İncele - EditoryalYalnız künye2020Preface
Gul, Muhammet; Celik, Erkan; Mete, Suleyman; Serin, Faruk
AtıfScopus1İncele - MakaleYalnız künye2020Scopus SJRQ1A manufacturing failure mode and effect analysis based on fuzzy and probabilistic risk analysis
Gul, Muhammet; Yucesan, Melih; Celik, Erkan
This study proposes an improved failure mode and effect analysis (FMEA) with fuzzy Bayesian Network (FBN) and fuzzy best-worst method (FBWM) to assess failures in plastic production. To eliminate the drawbacks of the classical risk priority number (RPN) computation of FMEA, this approach is developed. Unlike classical RPN, a new parameter hierarchy is constructed, and three sub-parameters are injected into the approach. These parameters are weighted by the aid of FBWM. Hereafter, a fuzzy rule-based system is constructed by incorporating Bayesian Network (BN). Also, a sensitivity analysis is performed to observe the final FMEA score changes in accordance with the change of subjective probability values. Finally, a comparative analysis with two approaches of classical FMEA and FBWM-based FMEA (without a fuzzy rule-based system incorporating BN) is fulfilled. The results of the study are strengthened with the experts’ opinions regarding the importance of failure modes for the final product and the whole system and supported them by experience feedback in the observed facility.
AtıfScopus68WoS59OpenAlex68İncele - MakaleYalnız künye2020Scopus SJRQ2The effect of graphene nano-sheet (GNS) weight percentage on mechanical and corrosion properties of AZ61 and AZ91 based magnesium matrix composites
Guler, Omer; Say, Yakup; Dikici, Burak
In this study, the effect of graphene nano-sheets (GNSs) on mechanical and corrosion properties of AZ61 and AZ91 based composites was investigated, detail. GNSs have been successfully produced by the liquid phase exfoliation (LPE) method and then, added AZ61 and AZ91 matrix with 01, 0.2, and 0.5 wt% GNSs for the production of the composites. The composite compacts were produced by powder metallurgy technique and sintered for 2 h at 500 °C under Ar atmosphere. The composite characterizations were carried out by scanning and transmission electron microscopes (SEM, TEM), electron dispersive spectroscope (EDS), Raman spectroscopy, and X-ray diffraction. The mechanical properties and corrosion behaviors of the composites have been compared with compression tests and potentiodynamic scanning (PDS) techniques, respectively. The results showed that the compressive strength of the composites increased with increasing GNS amount in both the AZ61 and AZ91 matrix alloys. The most susceptible composites to corrosion for both AZ61 and AZ91 matrix were observed in the 0.5 wt% GNS containing structures. However, there is a certain ratio of GNS in the Mg matrix to achieve good corrosion resistance.
AtıfScopus29WoS25OpenAlex33İncele - MakaleYalnız künye2020Scopus SJRQ1Linear, nonlinear optical and photon attenuation properties of La3+ doped tellurite glasses
Boukhris, Imed; Kebaili, Imen; Sayyed, M.I.; Askin, A.; Rammah, Y.S.
Linear and nonlinear optical features of La3+ doped tellurite glasses in the form 75TeO2–10ZnO –5Li2O –(10-x)Nb2O5 –xLa2O3: x = 0, 0.5, 1.0, 1.5, 2.0, and 2.5 in mol% (abbreviated as La0.0. La0.5, La1.0, La1.5, La2.0, and La2.5) were investigated. Also, the γ-photons attenuation parameters were tested utilizing Geant4 simulation code. Results revealed that the molar polarizability (αmolar) takes values from 8.685 × 10−24 to 7.933 × 10−24 cm3, while the molar refraction (Rmolar) changes from 21.886 to 20.219 (cm3/mol) for La0.0 to La2.5 glasses. The static dielectric constant (εstatic) varies from 6.368 to 5.191, whereas optical electronegativity (χ*) varies from 0.690 to 0.852 for La0.0-La2.5 glasses. Non-linear optical susceptibility (χ3) decreases from 5.675 × 10−12 to 2.109 × 10−12 (esu) with increment La2O3 content in the glasses, while non-linear refractive index (n2optical) decreases from 8.472 × 10−11 to 3.488 × 10−11 (esu). The radiation attenuation characteristics for the tested glasses were investigated with the help of Geant4 code. The mass attenuation coefficient (μm) was simulated between 0.284 and 2.506 MeV. The influnce of La2O3 on the shielding parameters was examined. Among the studied glasses, La2.5 posseses the highest μm values. Also, La2.5 sample has the lowest transmission fraction, which implies that more photons can be attenuated with La2.5 glass using a thin glass layer. From the transmission fraction results, we found that thick glasses are needed to attenuate gamma rays coming at high energies. At 0.511 MeV, the half value layer (HVL) value of the La0.0 glass is 1.49 cm while, at the same energy, the HVL value of the La2.5 glass is 1.44 cm.
AtıfScopus34OpenAlex35İncele - MakaleYalnız künye2020Scopus SJRQ2Investigation of the radiation shielding capability of xPbO – (50 - x) BaO – 50 B 2O 3 glass system using Geant4, Fluka, WinXCOM and comparison of data with the experimental data
Aşkin, A.; Mutuwong, C.; Nutaro, T.; Dal, M.
In this study, mass attenuation coefficient (μm), transmission fractions (T), effective atomic numbers (Z eff) and half-value layer (HVL) of the xPbO –(50 - x) BaO –50 B 2O 3 (where x=10,20,30,40mol%) glass system have been determined from the Monte Carlo simulations carried out with Geant4 and Fluka simulation toolkits and WinXCOM database software. The calculated results were compared with the experimentally obtained μm values of the selected glass in order to validate the Geant4 model of HPGe detector and Fluka model of NaI(Tl) detectors. T, Z eff and HVL shielding parameters of the studied glass system indicate that increase of PbO content from 10 to 40% results in a better shielding behaviour thanks to the high atomic number of lead.
AtıfScopus12WoS8OpenAlex12İncele - MakaleAçık Erişim2020Scopus SJRQ1Enhanced corrosion properties of biological NiTi alloy by hydroxyapatite and bioglass based biocomposite coatings
Say, Y.; Aksakal, B.
Enhanced corrosion resistance is always an obligatory property in biomedical applications. For this purpose, the surfaces of NiTi alloy were duplex coated both by Hydroxyapatite (HA)/Silver (Ag) and BioGlass (BG)/Silver (Ag) using the sol-gel method. The surface morphologies, and corrosion behaviours of the coatings were examined via SEM, EDS, XRD, and mechanically, by means of hardness as well as adhesion and corrosion tests. SEM analyses showed that the homogenous and crack-free structures were obtained in the biocomposite coatings. Spherical-like structures in the coatings were observed and pitting type of corrosion was formed in the biocomposite coated NiTi surfaces. After the corrosion tests, enhanced corrosion resistance was observed in both HA- and BG- based coatings. However, HA-based HA/Ag coatings on NiTi alloys were obtained to have higher adhesion strength as well as higher corrosion resistance compared to the BG-based biocomposite coatings. The findings in the present study can help the design of future implants with higher corrosion resistance.
AtıfScopus38WoS37OpenAlex42İncele - MakaleAçık Erişim2020Scopus SJRQ4Parameter estimation of some archimedean copulas based on minimum cramer-von-mises distance
Susam, Selim Orhun
The purpose of this paper is to introduce a new estimation method for estimating the Archimedean copula dependence parameter in the non-parametric setting. The estimation of the dependence parameter has been selected as the value that minimizes the Cramer-von-Mises distance which measures the distance between Empirical Bernstein Kendall distribution function and true Kendall distribution function. AMonte Carlo study is performedto measure the performance of thenewestimator and compared to conventional estimation methods. In terms of estimation performance, simulation results show that the proposed Minumum Cramer-von-Mises estimation method has a good performance for low dependence and a small sample size when compared with the other estimation methods. The new minimum distance estimation of the dependence parameter is applied to model the dependence of two real data sets.
AtıfScopus13WoS9OpenAlex10İncele - MakaleAçık Erişim2020Scopus SJRQ3Antioxidant effects of oleuropein on hydrogen peroxide-induced neuronal stress-an in vitro study
Kucukgul, Altug; Isgor, Mehmet M.; Duzguner, Vesile; Atabay, Meryem N.; Kucukgul, Azime
Background: Persistent oxidative stress can lead to chronic inflammation and mediate most chronic diseases including neurological disorders. Oleuropein has been shown to be a potent antioxidant molecule in olive oil leaf having antioxidative properties. Objective: The aim of this study was to investigate the protective effects of oleuropein against oxidative stress in human glioblastoma cells. Methods: Human glioblastoma cells (U87) were pretreated with oleuropein (OP) essential oil 10 µM. After 30 minutes, 100 µM H2 O2 was added to the cells for three hours. Cell survival was quantified by colorimetric MTT assay. Glutathione level, total oxidant capacity, total antioxidant capacity and nitric oxide levels were determined by using specific spectrophotometric methods. The relative gene expression level of iNOS was performed by qRT-PCR method. Results: According to viability results, the effective concentration of H2 O2 (100µM) significantly decreased cell viability and oleuropein pretreatment significantly prevented the cell losses. Oleuropein regenerated total antioxidant capacity and glutathione levels decreased by H2 O2 exposure. In addition, nitric oxide and total oxidant capacity levels were also decreased after administration of oleuropein in treated cells. Conclusion: Oleuropein was found to have potent antioxidative properties in human glioblastoma cells. However, further studies and validations are needed in order to understand the exact neuroprotective mechanism of oleuropein.
AtıfScopus23OpenAlex24İncele