Beslenme ve Diyetetik Bölümü Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12514/223

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Biosynthesis of silver nanoparticles from Arum dioscoridis plant leaf aqueous extract: anticancer and antimicrobial properties
(Gültekin ÖZDEMİR, 2023) İpek, Polat; Baran, Mehmet Fırta; Yıldız, Reşit; Hatipoğlu, Abdulkerim
This study was carried out to synthesize silver nanoparticles (AgNPs) from Arum dioscoridis (AD) leaf extract and to investigate the cytotoxic and antipathogenic effects of them. The plant material had a reducing and stabilizing effect on the synthesized nanomaterial. During the plant-mediated synthesis of nanomaterials, no substances that would cause environmental pollution were used. For the structural characterization of AD-AgNPs, Ultraviolet-visible (UV-vis) Spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), Electron Dispersive X-ray (EDX) Spectroscopy, Fourier Transform Infrared (FT-IR) Spectroscopy, Transmission Electron Microscopy (TEM), X-ray Diffractometer (XRD), Atomic Force Microscopy (AFM) and Zetasizer analyses were performed. The produced AgNPs showed maximum surface plasmon resonance at 431.67 nm and had mostly spherical morphology. The zeta potential value of the nanomaterial was -9.76 mV and the average powder crystal size was 31.48 nm. The minimum inhibitory concentration (MIC) values (mg/L) of AD-AgNPs on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Candida albicans were 0.25, 2.00, 0.125, 4.00, and 1.00, respectively. After 24 and 48 hours of application by MTT [3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolium bromid] assay, the half-maximal inhibitory concentrations (IC50: μg/mL) of AD-AgNPs on human colon adenocarcinoma cell (CACO-2), human breast cancer cell (MCF-7), glioblastoma multiforme cell (T98-G), and healthy human umbilical vein endothelial cell (HUVEC) lines were determined as 2.977, 2.801, 5.694, 4.392; 2.115, 2.300, 2.612, 4.091, respectively.
Citation - WoS: 46
Citation - Scopus: 52
Corrosion behavior of mild steel in 1 M HCl with Cyclotrichium niveum as a green inhibitor
(Elsevier, 2024) Yıldız, Reşit; Arslanhan, Selim; Döner, Ali; Baran, Mehmet Fırat
Recently, green inhibitors are replacing classical inhibitors in the acid cleaning industry due to very low cost, environmentally friendly and none toxic. In this study, Cyclotrichium niveum is used as a potential green corrosion inhibitor to investigate the corrosion behavior of mild steel (MS) in chloride solution using electrochemical, morphological, structural and quantum chemical methods. Fifty-three flavonoids are detected in methanol extract of cyclotrichium niveum by LC/ESI-MS/MS. While icorr values decreased, Rp and inhibition efficiencies values derived from electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) increased in increasing inhibitor concentrations. Maximum inhibition efficiency is found to be 97.3%, that is the almost highest value, when compared to previous studies and plant extract is classified as a mixed type inhibitor with respect to the potentiodynamic polarization (PDP). The model that best fits the experimental values is the Langmuir isotherm. The temperature effect is also studied in the range of 25–55 ○C. Higher activation energy is obtained in the presence of inhibitor, suggesting that it acts as an efficient inhibitor by forming a physical barrier to the charge and mass transfer reaction, leading to reduction in corrosion rate. Scanning electron and atomic force microscopies showed the more uniform, crack and pits free structure, confirming that there is a protective film over the MS surface for inhibited solution. XPS analysis showed the existence of C, O, and Fe atoms on the MS surface. Quantum chemical calculation manifested the adsorption mechanism associated with the electronic structure of the molecules. The findings of this work can be applicable in chemical cleaning process with acid treatment.
Electrocatalysis property of CuZn electrode with Pt and Ru decoration
(2021) Toprak Döşlü, Serap; DÖNER, ALİ; Yıldız, Reşit
Electrocatalysis properties strongly depend on the interaction of metallic particles and this interaction enables to change the electronic structure of alloys which enhances the catalytic activity. This property is the key factor in the developing of cost-effective and efficient Hydrogen Evolution Reaction (HER) electrocatalysts for sustainable hydrogen production. In this study, novel electrocatalysts which are decorated with Pt and Ru have been developed for HER electrocatalysis. Microscopic analysis such as scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD) and atomic force microscopy (AFM) are performed to determine the morphological and compositional structures. Electrocatalysis properties are evaluated by cathodic current-potential curves, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) in 1.0 M KOH solution. Chronoamperometry (CA) and cycle tests are used for stability/durability of electrocatalysts. Results show that a small onset potential of the porous Cu/Ni/CuZnePt is obtained for HER. Exchange current density and polarization resistance are found to be 5.39 mA cm2 and 2.0 U cm2 at overpotential of 100 mV for porous Cu/Ni/CuZnePt, respectively, indicating that Cu/Ni/CuZnePt is higher electrocatalytic properties than the others. Moreover, very low overpotentials at 10 and 40 mA cm2 are obtained on porous Cu/ Ni/CuZnePt compared with porous Cu/Ni/CuZneRu and Cu/Ni/CuZn. Porous Cu/Ni/CuZn ePt also displays excellent stability/durability in test solution. The remarkable electrocatalysis properties of porous Cu/Ni/CuZnePt can be explained due to high porous structure, leaching of Zn from the deposit, intrinsic activity of Pt as well as changing in the electronic structure. It should be considered that porous Cu/Ni/CuZnePt is of high corrosion resistance in test solution for 120 h, which makes it good candidate for HER.
Electrochemical Hydrogen Production by Using G/Ni/Ag Cathode
Yıldız, Reşit; Doğru, Mert, Başak; Toprak Döşlü, Serap
In this study graphite (G) electrode was coated with nickel and decorated with silver (G/Ni/Ag) and we used this modified electrode as cathode in alkaline water electrolysis system. The electrochemical characterization of G, G/Ni and G/Ni/Ag was achieved via cyclic voltammetry technique. Hydrogen evolution performance of electrodes was investigated via chronoamperomety, cathodic polarization curves and electrochemical impedance measurements. Results showed that hydrogen production efficiency significantly increased and charge transfer resistance of electrodes decreased via Ni/Ag multilayer.
Citation - WoS: 22
Citation - Scopus: 25
Experimental and theoretical investigation of adsorption and inhibition properties of 2-Amino-1,3,5-triazine-4,6-dithiol against corrosion in hydrochloric acid solution on mild steel
(Elsevier, 2023) Arslanhan, Selim; Yıldız, Reşit; Döner, Ali
In this work, 2-Amino-1,3,5-triazine-4,6-dithiol (2-ATD) as novel and high efficiency corrosion inhibitor has been investigated for mild steel (MS) corrosion in 0.5 M HCl solution using electrochemical methods, scanning electron microscopy (SEM), energy disperse X-ray spectroscopy (EDX), atomic force microscopy (AFM) and quantum chemical calculation methods. Potentiodynamic polarization (PDP) curves indicate that 2-ATD is mixed type inhibitor, corrosion inhibition efficiency increased with increasing inhibitor concentration and reached its value of 96.5%. Evolution of exposure time versus corrosion behavior of 2-ATD is examined in corrosive medium. While corrosion potential (Ecorr) shifted more negative values, polarization resistances (Rp) decreased after 120 h exposure time due to the corrosion process. H2 volume is measured in uninhibited and inhibited solutions (10 mM 2-ATD) after 120 h exposure time. Very low volume (3.6 mL cm-2) of H2 is obtained on MS electrode in inhibited solution after 120 h of exposure, indicating that 2-ATD covers the entire surface against aggressive attack and retards the both anodic dissolution of MS and cathodic hydrogen evolution reactions. The adsorption process proposal is the Langmuir isotherm which is most suitable. Adsorption and thermodynamic parameters show that 2-ATD has a strong adsorption effect onto MS surface and includes mixed adsorption style (physical and chemical). Corrosion current density increases with increasing temperature and high activation energy (Ea) proves the strong adsorption of 2-ATD on the MS surface. Anti-corrosion mechanism of 2-ATD is described more detail with the potential of zero charge method. SEM, EDX and AFM analysis support the obtained results of electrochemical methods and confirm the existence of protective layer and strong adsorption of 2-ATD on the MS surface. Chronoamperometry test shows that current densities are almost constant whole experiment in the presence of organic film. Finally, quantum chemical calculation method of 2-ATD in blank solution is performed to investigate the active sites for possible attachment with MS surface.
Experimental and theoretical study on hydrogen production by using Ag nanoparticle‐decorated graphite/Ni cathode
(2021) Yıldız, Reşit; Doğru, Mert, Başak; KARAZEHİR, TOLGA; GÜRDAL DURĞUN, YELİZ; Toprak Döşlü, Serap
In this study, graphite (G) electrode was coated with nickel and decorated with silver nanoparticles (G/Ni/Ag) with the help of galvanostatic method, and electrodes were used as a cathode in alkaline water electrolysis system. The characterization was achieved using X-ray diffraction and field emission scanning electron microscopy. Hydrogen evolution performance of electrodes was investigated via cyclic voltammetry, chronoamperometry, cathodic polarization curves, and electrochemical impedance measurements. Electrochemical results showed that hydrogen production efficiency significantly increased and charge transfer resistance decreased via G/Ni/Ag. The electrochemical water splitting performance of G/Ni/Ag, was established in a joint experimental and computational effort. Water and proton adsorption on Ag-decorated Ni surface were investigated using density functional theory. Electronic structure calculations identified the role of Ag adatom and Ni surface on water and proton adsorptions. From the computational studies, O in water was more reliable to adsorb at the bridge position of the Ag and Ni atoms, leading improved orbital overlap between H and Ni atoms and maximized chemical and physical interactions between the H2O molecules. Therefore, the Ag-decorated Ni(111) surface provides preferable adsorption site for the O atom in water and direct interactions between water Hs and available surface Ni atoms promote water dissociation.
Citation - WoS: 9
Citation - Scopus: 10
Green Synthesis of Silver Nanoparticles Derived from Papaver rhoeas L. Leaf Extract: Cytotoxic and Antimicrobial Properties
(MDPI, 2023) İpek, Polat; Yıldız, Reşit; Baran, Mehmet Fırat; Hatipoğlu, Abdülkerim; Baran, Ayşe; Sufianov, Albert; Beylerli, Ozal
In the last few decades, the search for metal nanoparticles as an alternative to cancer treatments and antibiotics has increased. In this article, the spectroscopic (ultraviolet-visible (UV-vis), electron-dispersing X-ray (EDX), and Fourier transform infrared (FT-IR)), microscopic (field emission scanning electron microscope (FE-SEM), transmission electron microscope (TEM), and atomic force microscope (AFM)), structural (X-ray diffractometer (XRD) and zetasizer), and analytic (thermogravimetric/differential thermal analyzer (TGA-DTA)) characterization of the silver nanoparticles (AgNPs) produced from Papaver rhoeas (PR) L. leaf extract are presented. PR-AgNPs are generally spherical and have a maximum surface plasmon resonance of 464.03 nm. The dimensions of the manufactured nanomaterial are in the range of 1.47-7.31 nm. PR-AgNPs have high thermal stability and a zeta potential of 36.1 mV. The minimum inhibitory concentration (MIC) values (mg L-1) of PR-AgNPs on Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Pseudomonas aeruginosa, and Candida albicans are 1.50, 0.75, 3.00, 6.00, and 0.37, respectively. In the study, the cytotoxic and proliferative effects of PR-AgNPs using the MTT (3-(4,5-dimethylthiazol-2-yl)-diphenyltetrazolium bromide) method on various cancer cell lines (CACO-2 (human colon adenocarcinoma cell), MCF-7 (human breast cancer cell), T98-G (glioblastoma multiforme cell), and healthy HUVEC (human umbilical vein endothelial cell)) cell lines are presented. After 24 and 48 h of the application, the half-maximum inhibitory concentration (IC50) values (mu g mL(-1)) of PR-AgNPs on HUVEC, CACO-2, MCF-7, and T98-G lines are 2.365 and 2.380; 2.526 and 2.521; 3.274 and 3.318; 3.472 and 3.526, respectively. Comprehensive in vivo research of PR-AgNPs is proposed to reveal their potential for usage in sectors such as nanomedicine and nanochemistry.
Relationship Between Geriatric Nutrition Risk Index, Urea Reduction Rate, Anthropometric Measurements and Biochemical Indicators in Adult Patients Receiving Hemodialysis Treatment: A Cross-Sectional Study
(Turkish Journal Of Health And Sport, 2022) Aslan Ceylan, Jiyan; Yıldız, Reşit
Background: It is very important to evaluate the nutritional status of patients, as malnutrition is the most common condition after hemodialysis treatment and increases the risk of mortality. We aimed to evaluate the relationships between Geriatric Nutritional Risk Index (GNRI), anthropometric measurement, biochemical markers, and Urea Reduction Rate (URR) of patients receiving hemodialysis treatment. Methods: This study included 66 patients who received hemodialysis treatment 3 days a week for at least the last 6 months. Weight, height, mid-arm circumference, waist circumference, triceps skinfold thickness, neck circumference and calf circumference of all patients were measured after the dialysis session. Predialysis blood samples were taken after an overnight fast. All laboratory parameters were measured using standard laboratory methods. In the analysis of the data, the SPSS (Statistical Package for the Social Sciences) package program was used. P value of <0.01 and <0.05 was considered as statistically significant. Results: 47% male and 53% female, with a mean age of 62.1±13.1 years, were included in the study. The mean GNRI score was 107.0±12.1, and 19.7% of the patients were found to have malnutrition. There was a positive correlation between GNRI and anthropometric measurement, negative correlation with URR. Hierarchical linear regression analysis showed that total protein and ferritin significantly predicted the GNRI. Conclusion: It is important to consider nutritional status, biochemical indicator and dialysis adequacy together for the management of chronic kidney disease. The number of studies in this field in Turkey is limited.
Citation - WoS: 12
Citation - Scopus: 12
A study for hydrogen evolution on Pt–MnCu electrocatalyst
(Elsevier, 2023) Yıldız, Reşit; Arslanhan, Selim; Döner, Ali
Electrocatalysts to be used in electrolysis, which is one of the hydrogen production methods, are very important. The development of electrocatalysts is related to the internal structure of combinated more than one metal. In the present work, the graphite substrate is coated with manganez (C/Mn), manganez-copper (C/MnCu) and this surface is modified with platinum nanoparticles (C/MnCu–Pt) using the electrodeposition method. Prepared electrocatalysts are used for characterization, hydrogen evolution reaction (HER) and stability using cyclic voltammetry (CV), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), X-ray diffraction (XRD), cathodic current-potential curves, electrochemical impedance spectroscopy (EIS) and chronoamperometry (CA). Hydrogen gas is measured in a basic environment by establishing an experimental electrolysis setup on these electrocatalysts. Results showed that binary MnCu enhances the characteristic current density of Tafel curves, reduces the polarization resistance and enhances the hydrogen gas volume compared to graphite substrate and single Mn coating. Apart from that, much more effective results are obtained on the C/MnCu–Pt electrocatalyst. Namely, a very high exchange current density (io = 5.50 mA cm−2), a very low polarization resistance (3.2 Ω cm2) and a very low overpotential (50 mV) at 10 mA cm−2 are obtained on the C/MnCu–Pt electrocatalyst. In addition to high performance, C/MnCu–Pt electrocatalyst exhibits good stability in alkaline medium.
The Study of 2, 4-Diamino-6-methly-1, 3, 5-triazine on the Corrosion Inhibition of Mild Steel in The Hydrochloric Acid Medium: Integrated Theoretical and Experimental Investigations
(Bingol University, 2023) Yıldız, Reşit
The aim of this study is the investigation of adsorption and corrosion behaviors of 2,4-Diamino-6-methly-1,3,5-triazine (2-DMT) on mild steel (MS) in 0.5 M HCI solution using many experimental and theoretical studies such as potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), adsorption isotherm, potential of zero charge (PZC), scanning electron (SEM), atomic force microscopies (AFM) and quantum chemical calculations. The results showed that 2-DMT has an outstanding anti-corrosion performance of 94.6% at an optimum concentration of 10 mM and the MS surface, which was exposed to the inhibited solution at 298 K, does not contain pits, cracks or deformations. Values of icorr are found to be 0.51, 0.22, 0.098, 0.072 and 0.039 mA cm-2 for blank solution and each concentration of 2-DMT. Hydrogen volumes are 90 and 4.6 mL cm-2 for blank solution and the existence of 10.0 mM 2-DMT, respectively. The observed adsorption is much more consistent with Langmuir. The high performance is explained by the effective adsorbing of organic matter to the MS surface. HOMO, LUMO energies and the energy gap (∆E) are -7.1980, -1.9959 and 5.2021 eV, respectively. Accordingly, it is suggested that this organic compound can be used in the industrial acid cleaning procedure.

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