Open Access. Powered by Scholars. Published by Universities.®

Digital Commons Network™

Open Access. Powered by Scholars. Published by Universities.®

TÜBİTAK

Discipline
Keyword
Publication Year
Publication

Articles 2701 - 2730 of 12093

Full-Text Articles in Entire DC Network

Tuning The Mechanical Properties And Degradation Properties Of Polydioxanoneisothermal Annealing, Xiliang Liu, Shaomin Feng, Xin Wang, Jin Qi, Dong Lei, Yadong Li, Wei Bai Jan 2020

Tuning The Mechanical Properties And Degradation Properties Of Polydioxanoneisothermal Annealing, Xiliang Liu, Shaomin Feng, Xin Wang, Jin Qi, Dong Lei, Yadong Li, Wei Bai

Turkish Journal of Chemistry

Polydioxanone (PPDO) is synthesized by ring-opening polymerization of p-dioxanone, using stannous octoate as the catalyst. The polarized optical micrograph (POM) shows thes pherulite growth rate of PPDO decreases with an increase in the isothermal crystallization temperature. PPDO is compression-molded into bars, and PPDO bars are subjected to isothermal annealing at a range of temperatures (Ta = 50, 60, 70, 80, 90, and 100 °C), and correspond to three different annealing times (ta = 1h, 2h, 3h). The effect on PPDO is investigated by using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). With …


Cover And Contents Jan 2020

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Cover And Contents Jan 2020

Cover And Contents

Turkish Journal of Chemistry

No abstract provided.


Synthesis And Structural Analysis Of Nonstoichiometric Ternary Fulleride K1.5ba0.25csc60, Havva Esma Okur Kutay Jan 2020

Synthesis And Structural Analysis Of Nonstoichiometric Ternary Fulleride K1.5ba0.25csc60, Havva Esma Okur Kutay

Turkish Journal of Chemistry

The existence of cation-vacancy sites in fullerides might lead to long-range ordering and generate a new vacancy-ordered superstructure. The purpose of this work is to search whether or not long-range ordering of vacant tetrahedral sites, namely superstructure emerges in nonstoichiometric K1.5Ba0.25CsC60 fulleride. Therefore, K1.5Ba0.25CsC60 with cation-vacancy sites is synthesized using a precursor method to avoid inadequate stoichiometry control and formation of impurity phases within the target composition. For this purpose, first, phase-pure K6C60, Ba6C60 and Cs6C60 precursors are synthesized. Stoichiometric quantities of these precursors are used for further reaction with C60 to afford K1.5Ba0.25CsC60. Rietveld analysis of the high-resolution synchrotron …


Synthesis And Characterization Of Hexagonal Boron Nitride Used For Comparison Of Removal Of Anionic And Cationic Hazardous Azo-Dye: Kinetics And Equilibrium Studies, Tuba Tarhan Jan 2020

Synthesis And Characterization Of Hexagonal Boron Nitride Used For Comparison Of Removal Of Anionic And Cationic Hazardous Azo-Dye: Kinetics And Equilibrium Studies, Tuba Tarhan

Turkish Journal of Chemistry

The purpose of this study was to compare the adsorption behavior of cationic and anionic dyes onto a hexagonal boron nitride (hBN) nanostructure that was rich in a negative charge. Herein, the hBN nanostructure was synthesized using boric acid as a precursor material. The characteristic peaks of the hBN nanostructure were performed using Fourier transform infrared (FT-IR) and Raman spectroscopies. The morphology and the particle size of hBN nanostructure were determined by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). During the studies, various essential adsorption parameters were investigated, such as the initial dye concentration, pH of the dye …


Characterization And Kinetics Analysis Of The Thermal Decomposition Of The Humic Substance From Hazelnut Husk, Fatma Kara, Duygu Adigüzel, Ufuk Atmaca, Murat Çeli̇k, Jale Nakti̇yok Jan 2020

Characterization And Kinetics Analysis Of The Thermal Decomposition Of The Humic Substance From Hazelnut Husk, Fatma Kara, Duygu Adigüzel, Ufuk Atmaca, Murat Çeli̇k, Jale Nakti̇yok

Turkish Journal of Chemistry

A humic substance was obtained from hazelnut husk using an alkali extraction. The chemical and morphological structure of the humic matter was characterized via elemental analysis, Fourier transform infrared spectrometry (FTIR), nuclear magnetic resonance, Brunauer-Emmet-Teller (BET) analysis, scanning electron microscopy (SEM), and thermogravimetric-FTIR (TG-FTIR). In addition, thermal analysis measurements TG analysis-differential thermogravimetry/differential scanning calorimetry (TGA-DTG/ DSC) were performed under dynamic air conditions to better determine the origin, physical and chemical structure, and decomposition process of the humic matter. The Kissinger-Akahira-Sunose (KAS) and Flynn-Wall-Ozawa (FWO) methods were used to calculate the kinetic parameters of the high-temperature decomposition process. It was observed …


Innovational Combination Of Hetero-Bifunctional N-Peg Quinoline Scaffolds Derivatives With Improved Anticancer Activity Against Breast And Colon Cancer Cell Lines And P-Glycoprotein, Cytochrome P450 Enzyme Activity Prediction, Mahesh Gaidhane, Ajay Ghatole, Kushal Lanjewar, Kishor Hatzade Jan 2020

Innovational Combination Of Hetero-Bifunctional N-Peg Quinoline Scaffolds Derivatives With Improved Anticancer Activity Against Breast And Colon Cancer Cell Lines And P-Glycoprotein, Cytochrome P450 Enzyme Activity Prediction, Mahesh Gaidhane, Ajay Ghatole, Kushal Lanjewar, Kishor Hatzade

Turkish Journal of Chemistry

Polyethylene glycol (PEG) is a polymer that is widely used as a carrier for drug delivery systems (DDS). A library of N-PEGylated quinoline derivatives of PEG molecular weight 200 was prepared rapidly after the activation of PEGs using maleic anhydride. Quinoline with a polymer backbone is essential as new material. PEG is a water-soluble nonionic polymer approved by food and drug organizations for medicine applications. Because of its nontoxic grapheme, it is widely utilized in numerous biochemical, cosmetic, pharmaceutical, and industrialized applications. The modern SwissADME is a web tool that stretches free admittance to a pool of hasty, yet solid, …


Catalytic Activity Of Novel Thermoplastic/Cellulose-Au Nanocomposites Prepared By Cryomilling, Joanna Kwiczak Yigitbasi Jan 2020

Catalytic Activity Of Novel Thermoplastic/Cellulose-Au Nanocomposites Prepared By Cryomilling, Joanna Kwiczak Yigitbasi

Turkish Journal of Chemistry

Due to environmental concerns, increasing attention has been focused on the application and preparation of biobased polymers and their blends. In this study, cellulose, the most spread biopolymer on Earth, was used in the preparation of novel cotton/polypropylene- Au and cotton/polyethylene-Au nanocomposites via a green mechanochemical approach. First, mechanoradicals were generated by ball milling of the cotton and thermoplastics under cryo conditions, and then, these radicals were used in the reduction of Au ions to Au nanoparticles (Au NPs). Nanocomposites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The application of mechanochemistry in …


Effective Synthesis Of Bicyclodienes Via Palladium-Catalyzed Asymmetric Allylic Alkylationand Ruthenium-Catalyzed Cycloisomerization, Ni̇zam Havare Jan 2020

Effective Synthesis Of Bicyclodienes Via Palladium-Catalyzed Asymmetric Allylic Alkylationand Ruthenium-Catalyzed Cycloisomerization, Ni̇zam Havare

Turkish Journal of Chemistry

[n.3.0]Bicycles (n = 3-6) can be synthesized using palladium-catalyzed asymmetric allylic alkylation followed by rutheniumcatalyzed cycloisomerization. New types of triarylphosphino-1,2-diaminooxazoline ligands show the same high levels of enantioselectivity observed with Trost ligand when employed in Pd-catalyzed allylic alkylation reactions. The enyne products of these allylic alkylation reactions were further elaborated using a Ru-catalyzed redox isomerization process, for which a mechanism is proposed.


Effect Of Ph On Lipid Oxidation Of Red Onion Skin Extracts Treated With Washed Tilapia (Oreochromis Niloticus) Muscle Model Systems, Senem Güner, Yavuz Yağiz, Zeynal Topalcengi̇z, Hordur G. Kristinsson, George Baker, Paul Sarnoski, Bruce A. Welt, Amarat Simonne, Maurice M. Marshall Jan 2020

Effect Of Ph On Lipid Oxidation Of Red Onion Skin Extracts Treated With Washed Tilapia (Oreochromis Niloticus) Muscle Model Systems, Senem Güner, Yavuz Yağiz, Zeynal Topalcengi̇z, Hordur G. Kristinsson, George Baker, Paul Sarnoski, Bruce A. Welt, Amarat Simonne, Maurice M. Marshall

Turkish Journal of Chemistry

The aim of the study was to investigate the effect of pH on the lipid oxidation of red onion skin extracts (ROSEs) treated with washed tilapia muscle model systems (WTMS). Minced and buffered washed samples were prepared at pH 6.3 and 6.8. The WTMS were treated with2 different concentrations of red onion skin prior to storage for 5 days. Lipid oxidation was investigated via peroxide values (PVs), thiobarbituric acid reactive substances (TBARS), and the formation of volatile compounds. Fatty acid profiles of the samples were also identified. The ROSEs were able to significantly suppress the PV (~71%) and TBARS (~42%) …


Chemical Composition, And Antibacterial And Antioxidant Activities Of Essential Oils From Laggera Tomentosa Sch. Bip. Ex Oliv. Et Hiern (Asteraceae), Tokuma Getahun, Vinit Sharma, Deepak Kumar, Neeraj Gupta Jan 2020

Chemical Composition, And Antibacterial And Antioxidant Activities Of Essential Oils From Laggera Tomentosa Sch. Bip. Ex Oliv. Et Hiern (Asteraceae), Tokuma Getahun, Vinit Sharma, Deepak Kumar, Neeraj Gupta

Turkish Journal of Chemistry

Laggera tomentosa Sch. Bip. ex Oliv. et Hiern (Asteraceae), an endemic Ethiopian medicinal plant, is traditionally used to treat various ailments. Previously, the chemical constituents of the essential oil (EO) of its leaves and inflorescence were documented. However, no data about the chemical compositions of other parts of the EOs of the plant have been reported to date. Moreover, there are no previous biological activity reports on any parts of the EOs of this plant. Thus, in this study, the EOs were isolated from the stem bark and roots of this plant by hydrodistillation and analyzed using gas chromatography-mass spectrometry …


Synthesis And Electrochemical Properties Of Copper(Ii), Manganese(Iii) Phthalocyanines Bearing Chalcone Groups At Peripheral Or Nonperipheral Positions, Hüseyi̇n Baş, Nuran Kahri̇man, Zekeri̇ya Biyiklioğlu Jan 2020

Synthesis And Electrochemical Properties Of Copper(Ii), Manganese(Iii) Phthalocyanines Bearing Chalcone Groups At Peripheral Or Nonperipheral Positions, Hüseyi̇n Baş, Nuran Kahri̇man, Zekeri̇ya Biyiklioğlu

Turkish Journal of Chemistry

In this study, new chalcone compound 1, new phthalonitrile derivatives 2 and 3, new copper(II), manganese(III) phthalocyanines bearing chalcone groups at peripheral or nonperipheral positions were synthesized. Electrochemistry of tetra-(4- {(2E)-3-[2-fluoro-4-(trifluoromethyl)phenyl]prop-2-enoyl}phenoxy) substituted Co(II)Pc and Mn(III)Pcs were studied with cyclic voltammetry (CV) to determine the redox properties of the phthalocyanines. According to the results, while the CuPcs 2a and 3a showed two Pc based reduction reactions and one Pc based oxidation reaction, MnPcs 2b and 3b gave two metal-based reduction reactions. All the redox processes are shifted toward positive potentials as a result of the increased electron-withdrawing ability of the trifluoromethyl …


Newly Synthesized Peripherally Octa-Substituted Zinc Phthalocyanines Carrying Halogenterminated Phenoxy-Phenoxy Moiety: Comparative Photochemical And Photophysicalfeatures, Erkan Kirbaç, Ali̇ Erdoğmuş Jan 2020

Newly Synthesized Peripherally Octa-Substituted Zinc Phthalocyanines Carrying Halogenterminated Phenoxy-Phenoxy Moiety: Comparative Photochemical And Photophysicalfeatures, Erkan Kirbaç, Ali̇ Erdoğmuş

Turkish Journal of Chemistry

This study reports the 3 new phthalonitrile derivatives, namely 4, 5 Bis-[4-(4-bromophenoxy) phenoxy] phthalonitrile (1), 4,5 Bis-[4-(4-chlorophenoxy) phenoxy]phthalonitrile (2), and 4, 5 Bis[4-(4-fluorophenoxy) phenoxy] phthalonitrile (3). Their octasubstituted zinc phthalocyanines (4, 5, 6) are reported for the first time in this study. The resulting compounds were characterized by utilizing some spectroscopic methods, such as UV-Vis, 1HNMR, FT-IR spectroscopy, as well as mass spectraand elemental analysis. To show photosynthesizer's potential, emission (FF), singlet oxygen (1O2), and photodegradation quantum yields (ΦΔ, Φd) of octaperipherally phthalocyanines (Pcs) were performed in the solutions, such as biocompatible solvent DMSO (dimethyl sulfoxide) as well as DMF …


Evaluation Of Carbonic Anhydrase And Paraoxonase Inhibition Activities And Molecular Docking Studies Of Highly Water-Soluble Sulfonated Phthalocyanines, Emre Güzel, Fati̇h Sönmez, Sultan Erkan, Kübra Çikrikci, Adem Ergün, Nahi̇t Gençer, Oktay Arslan, Makbule Koçak Jan 2020

Evaluation Of Carbonic Anhydrase And Paraoxonase Inhibition Activities And Molecular Docking Studies Of Highly Water-Soluble Sulfonated Phthalocyanines, Emre Güzel, Fati̇h Sönmez, Sultan Erkan, Kübra Çikrikci, Adem Ergün, Nahi̇t Gençer, Oktay Arslan, Makbule Koçak

Turkish Journal of Chemistry

The investigation of carbonic anhydrase and paraoxonase enzyme inhibition properties of water-soluble zinc and gallium phthalocyanine complexes (1 and 2) are reported for the first time. The binding of p-sulfonylphenoxy moieties to the phthalocyanine structure favors excellent solubilities in water, as well as providing an inhibition effect on carbonic anhydrase (CA) I and II isoenzymes and paraoxonase (PON1) enzyme. According to biological activity results, both complexes inhibited hCA I, hCA II, and PON1. Whereas 1 and 2 showed moderate hCA I and hCA II (off-target cytosolic isoforms) inhibitory activity (Ki values of 26.09 μM and 43.11 μM for hCA I …


Design Of Novel Substituted Phthalocyanines; Synthesis And Fluorescence, Dft,Photovoltaic Properties, Mehmet Sali̇h Ağirtaş, Derya Güngördü Solğun, Ümi̇t Yildiko, Abdullah Özkartal Jan 2020

Design Of Novel Substituted Phthalocyanines; Synthesis And Fluorescence, Dft,Photovoltaic Properties, Mehmet Sali̇h Ağirtaş, Derya Güngördü Solğun, Ümi̇t Yildiko, Abdullah Özkartal

Turkish Journal of Chemistry

The 4-(2-[3,4-dimethoxyphenoxy] phenoxy) phthalonitrile was synthesized as the starting material of new syntheses. Zinc, copper, and cobalt phthalocyanines were achieved by reaction of starting compound with Zn(CH3COO)2, CuCl2, and CoCl2 metal salts. Basic spectroscopic methods such as nuclear magnetic resonance electronic absorption, mass and infrared spectrometry were used in the structural characterization of the compounds. Absorption, excitation, and emission measurements of the fluorescence zinc phthalocyanine compound were also investigated in THF. Then, structural, energy, and electronic properties for synthesized metallophthalocyanines were determined by quantum chemical calculations, including the DFT method. The bandgap of HOMO and LUMO was determined to be …


Biosynthesis Of Silver Nanoparticles Using Onosma Sericeum Willd. And Evaluation Oftheir Catalytic Properties And Antibacterial And Cytotoxic Activity, Selda Doğan Çalhan, Mustafa Gündoğan Jan 2020

Biosynthesis Of Silver Nanoparticles Using Onosma Sericeum Willd. And Evaluation Oftheir Catalytic Properties And Antibacterial And Cytotoxic Activity, Selda Doğan Çalhan, Mustafa Gündoğan

Turkish Journal of Chemistry

In this study, silver nanoparticle (AgNP) synthesis was carried out using Onosma sericeum Willd. aqueous extract for the first time, with a simple, economical, and green method without the need for any other organic solvent or external reducing or stabilizing agent. A variety of AgNPs, all of different particle sizes, were synthesized by controlling the silver ion concentration, extract volume, temperature, and pH. It was determined that the optimum conditions for AgNP synthesis were 1 mM AgNO3, pH 8, 25 °C, 20 g/200 mL extract, silver nitrate, and extract ratio 5:1 (v/v). The AgNPs were defined using UV-Vis spectroscopy, field …


Synthesis And Pharmacological Effects Of Novel Benzenesulfonamides Carryingbenzamide Moiety As Carbonic Anhydrase And Acetylcholinesterase Inhibitors, Mehtap Tuğrak, Hali̇se İnci̇ Gül, Bariş Anil, İlhami̇ Gülçi̇n Jan 2020

Synthesis And Pharmacological Effects Of Novel Benzenesulfonamides Carryingbenzamide Moiety As Carbonic Anhydrase And Acetylcholinesterase Inhibitors, Mehtap Tuğrak, Hali̇se İnci̇ Gül, Bariş Anil, İlhami̇ Gülçi̇n

Turkish Journal of Chemistry

N-(1-(4-Methoxyphenyl)-3-oxo-3-((4-(N-(substituted)sulfamoyl)phenyl)amino)prop-1-en-1-yl)benzamides 3a - g were designed since sulfonamide and benzamide pharmacophores draw great attention in novel drug design due to their wide range of bioactivities including acetylcholinesterase (AChE) and human carbonic anhydrase I and II (hCA I and hCA II) inhibitory potencies. Structure elucidation of the compounds was carried out by 1H NMR, 13C NMR, and HRMS spectra. In vitro enzyme assays showed that the compounds had significant inhibitory potential against hCA I, hCA II, and AChE enzymes at nanomolar levels. Ki values were in the range of 4.07 ± 0.38 - 29.70 ± 3.18 nM for hCA I and …


Computational And Biological Studies Of Novel Thiazolyl Coumarin Derivatives Synthesized Through Suzuki Coupling, Shaista Parveen, Saima Kalsoom, Rifhat Bibi, Ambreen Asghar, Abdul Hameed, Waqar Ahmed, Abbas Hassan Jan 2020

Computational And Biological Studies Of Novel Thiazolyl Coumarin Derivatives Synthesized Through Suzuki Coupling, Shaista Parveen, Saima Kalsoom, Rifhat Bibi, Ambreen Asghar, Abdul Hameed, Waqar Ahmed, Abbas Hassan

Turkish Journal of Chemistry

The current investigation presents the synthesis, computational molecular-docking and biological activity studies of arylated thiazole coumarins. Aryl substituted thiazolyl coumarin derivatives were synthesized via Suzuki cross-coupling reaction. A detailed reaction condition optimization revealed that the Pd-PEPPSI-IPent precatalyst in only 2 mol% loading resulted in the desired product with high yield. The aim of this study was to examine the antimicrobial behavior of thiazole coumarin derivatives through in vitro and in silico studies. All the compounds showed activity against both antibacterial strains, Staphylococcus aureus and Escherichia coli, except 5d. Similarly, the compounds 5a, 5b, and 5d were found to be active …


Synthesis And Molecular Docking Studies Of Quinoline Derivatives As Hiv Non-Nucleoside Reverse Transcriptase Inhibitors, Nivedita Bhardwaj, Diksha Choudhary, Akashdeep Pathania, Somesh Baranwal, Pradeep Kumar Jan 2020

Synthesis And Molecular Docking Studies Of Quinoline Derivatives As Hiv Non-Nucleoside Reverse Transcriptase Inhibitors, Nivedita Bhardwaj, Diksha Choudhary, Akashdeep Pathania, Somesh Baranwal, Pradeep Kumar

Turkish Journal of Chemistry

Quinoline moiety is an important scaffold in the field of drug discovery and drug development, with a wide range of pharmacological activities. Quinoline derivatives are potent inhibitors for reverse transcriptase, which is responsible for the conversion of single-stranded viral RNA into double-stranded viral DNA.In the present study, we have designed and synthesized 2 series, namely pyrazoline and pyrimidine containing quinoline derivatives as non nucleoside reverse transcriptase inhibitors (NNRTIs). Eleven compounds were synthesized and characterized by 1H and 13C NMR and mass spectrophotometry. The synthesized compounds were also docked on an HIV reverse transcriptase binding site (PDB: 4I2P); most of these …


Blue Tio2 Nanotube Arrays As Semimetallic Materials With Enhanced Photoelectrochemical Activity Towards Water Splitting, Naeimeh Sadat Peighambardoust, Umut Aydemir Jan 2020

Blue Tio2 Nanotube Arrays As Semimetallic Materials With Enhanced Photoelectrochemical Activity Towards Water Splitting, Naeimeh Sadat Peighambardoust, Umut Aydemir

Turkish Journal of Chemistry

In the past years there has been a great interest in self-doped TiO2 nanotubes (blue TiO2 nanotubes) compared to undoped ones owing to their high carrier density and conductivity. In this study, blue TiO2 nanotubes are investigated as photoanode materials for photoelectrochemical water splitting. Blue TiO2 nanotubes were fabricated with enhanced photoresponse behavior through electrochemical cathodic polarization on undoped and annealed TiO2 nanotubes. The annealing temperature of undoped TiO2 nanotubes was tuned before cathodic polarization, revealing that annealing at 500 °C improved the photoresponse of the nanotubes significantly. Further optimization of the blue TiO2 nanotubes was achieved by adjusting the …


Chemical Composition, Antimicrobial, And Lipase Enzyme Activity Of Essential Oil And Solvent Extracts From Serapias Orientalis Subsp. Orientalis, İshak Eri̇k, Gözde Kiliç, Eli̇f Öztürk, Şengül Alpay Karaoğlu, Nuretti̇n Yayli Jan 2020

Chemical Composition, Antimicrobial, And Lipase Enzyme Activity Of Essential Oil And Solvent Extracts From Serapias Orientalis Subsp. Orientalis, İshak Eri̇k, Gözde Kiliç, Eli̇f Öztürk, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

The volatile components of essential oil (EO), SPME, and SPME of solvent extracts (n-hexane, methanol, and water) obtained from fresh Serapias orientalis subsp. orientalis(Soo) were analyzed by GC-FID/MS. EO of Soo gave 11 compounds in the percentage of 99.97%; capronaldehyde (37.01%), 2-(E)-hexenal (23.19%), and n-nonanal (19.05%) were found to be major constituents. SPME GC-FID/MS analyses of fresh plant and solvent extracts of Soo revealed 7, 12, 7, and 4 compounds within the range of 99.7% to 99.9%. Limonene (76.5%, 41.7%, and 61.3%) was the major compound in SPMEs of the n-hexane and methanol extracts. α-Methoxy-p-cresol (52.9%) was the main component …


Comparison Of Antioxidant Capacities And Antioxidant Components Of Commercial Bitter Melon (Momordica Charantia L.) Products, Esi̇n Akyüz, Sercan Türkoğlu, Kevser Sözgen Başkan, Esma Tütem, Mustafa Reşat Apak Jan 2020

Comparison Of Antioxidant Capacities And Antioxidant Components Of Commercial Bitter Melon (Momordica Charantia L.) Products, Esi̇n Akyüz, Sercan Türkoğlu, Kevser Sözgen Başkan, Esma Tütem, Mustafa Reşat Apak

Turkish Journal of Chemistry

In this study, the total phenolic contents and total antioxidant capacities of some commercial bitter melon products (powder, packaged powder, capsule, paste in olive oil), and of unripe and ripe fruits were determined by spectrophotometric and chromatographic methods. The total antioxidant capacities of unripe and ripe bitter melon samples, determined by using the CUPRAC (cupric reducing antioxidant capacity assay) and ABTS (2,2'-Azinobis-(3-Ethylbenzthiazolin-6-Sulfonic Acid)/HRP (horseradish peroxidase) methods, were 42.5 and 36.3 μmol TRE (Trolox equivalent) g-1, and 8.7 and 7.0 μmol TRE g-1, respectively. The TAC (total antioxidant capacity) order of the studied samples using the same 2 methods were determined …


Design, Synthesis, Cytotoxic Activity, And Apoptosis Inducing Effects Of 4- And N-Substituted Benzoyltaurinamide Derivatives, Özlem Akgül, Mümi̇n Alper Erdoğan, Dervi̇ş Bi̇ri̇m, Çağla Kayabaşi, Cumhur Gündüz, Güli̇z Armagan Jan 2020

Design, Synthesis, Cytotoxic Activity, And Apoptosis Inducing Effects Of 4- And N-Substituted Benzoyltaurinamide Derivatives, Özlem Akgül, Mümi̇n Alper Erdoğan, Dervi̇ş Bi̇ri̇m, Çağla Kayabaşi, Cumhur Gündüz, Güli̇z Armagan

Turkish Journal of Chemistry

In this study, a group of 4-substituted benzoyltaurinamide derivatives were designed, synthesized, and investigated for their anticancer activity against three cancer cell lines and one nontumorigenic cell line by MTT assay. Among the final compounds, methoxyphenyl derivatives 14, 15, 16 were found to be effective against all the tested cancerous cell lines with promising selectivity. The most active compounds were further evaluated to determine the molecular mechanism of their anticancer activity by using western blot assay and the Annexin V-FITC/PI test. Compound 14 (in SH-SY5Y and MDA-MB-231 cell lines) and 15 (in SH-SY5Y cell line) were found to induce intrinsic …


Processing Impact On Tocopherols And Triglycerides Composition Of Soybean Oil And Its Deodorizer Distillate Evaluated By High-Performance Liquid Chromatography, Zahid Hussain Laghari, Syed Tufail Hussain Sherazi, Hami̇de Fi̇li̇z Ayyildiz, Mustafa Topkafa, Hüseyi̇n Kara, Sarfaraz Ahmed Mahesar, Siraj Uddin Jan 2020

Processing Impact On Tocopherols And Triglycerides Composition Of Soybean Oil And Its Deodorizer Distillate Evaluated By High-Performance Liquid Chromatography, Zahid Hussain Laghari, Syed Tufail Hussain Sherazi, Hami̇de Fi̇li̇z Ayyildiz, Mustafa Topkafa, Hüseyi̇n Kara, Sarfaraz Ahmed Mahesar, Siraj Uddin

Turkish Journal of Chemistry

In the present study, high-performance liquid chromatography (HPLC) was used for the separation of tocopherols and triglycerides of processed soybean oil and deodorizer distillate (DD). The results of normal and reversed-phase modes of HPLC revealed that concentrations of tocopherols and triglycerides content were decreased during the neutralization, bleaching, and deodorization processes. The loss of individual tocopherols ranged between 55.16% and 63.25%. During processing, triglycerides containing stearic-oleic-linoleic (SOL) moieties and palmitic-palmitic-linoleic (PPL) fragments showed greater reduction up to 38.14% and 37.69%, respectively. Among tocopherols and triglycerides; γ-tocopherol and oleic-oleic-oleic (OOO) were found to be in greater concentrations 5.53% and 19.78%, respectively …


Structural Insights Of Two Novel N-Acetyl-Glucosaminidase Enzymes Through In Silico Methods, Ari̇f Sercan Şahutoğlu, Hati̇ce Duman, Steven Alex Frese, Sercan Karav Jan 2020

Structural Insights Of Two Novel N-Acetyl-Glucosaminidase Enzymes Through In Silico Methods, Ari̇f Sercan Şahutoğlu, Hati̇ce Duman, Steven Alex Frese, Sercan Karav

Turkish Journal of Chemistry

EndoBI-1 and EndoBI-2 are two endo-β-N-acetylglucosaminidase isoenzymes that cleave N-N'-diacetylchitobiosyl moieties found in various types of native N-glycans. These N-glycans are indigestible by human infants and adults due to the lack of responsible glycosyl hydrolases and they act as selective prebiotics for a probiotic microorganism, Bifidobacterium longum subsp. infantis, in the large intestine. The selectivity and the thermostability of EndoBI-1 and EndoBI-2 suggest that these enzymes may be useful for many scientific and industrial applications. In this study, the growing numbers of homologous sequences in different databases were exploited in a comparative approach to investigate structural properties of EndoBI-1 and …


Highly Luminescent Water-Dispersed Silicon Quantum Dots For Fluorometric Determination Of Oxytetracycline In Milk Samples, Hayri̇ye Eda Şatana Kara, Burak Demi̇rhan, Buket Er Demi̇rhan Jan 2020

Highly Luminescent Water-Dispersed Silicon Quantum Dots For Fluorometric Determination Of Oxytetracycline In Milk Samples, Hayri̇ye Eda Şatana Kara, Burak Demi̇rhan, Buket Er Demi̇rhan

Turkish Journal of Chemistry

A fluorescent probe based on silicon quantum dots (SiQDs) was developed for the selective and sensitive detection of oxytetracycline (OTC) via the inner filter effect (IFE). The water-soluble fluorescent SiQD was synthesized based on the reaction of 3-Aminopropyltriethoxysilane (APTES) and sodium citrate as precursors by the one-pot hydrothermal process. The strong fluorescence emission of quantum dots (QDs) was obtained at 440 nm when excited at 350 nm and OTC had a broad absorption band between 200 and 400 nm. The excitation spectrum of SiQDs was completely overlapped with the absorption spectrum of OTC. The light at an excitation wavelength of …


Fabrication And Characterization Of Boric Acid-Crosslinked Ethyl Cellulose And Polyvinyl Alcohol Films As Potential Drug Release Systems For Topical Drug Delivery, Nasrin Aliasgharlou, Farzin Asghari Sana, Saba Khoshbakht, Pezhman Zolfaghari, Hamed Charkhian Jan 2020

Fabrication And Characterization Of Boric Acid-Crosslinked Ethyl Cellulose And Polyvinyl Alcohol Films As Potential Drug Release Systems For Topical Drug Delivery, Nasrin Aliasgharlou, Farzin Asghari Sana, Saba Khoshbakht, Pezhman Zolfaghari, Hamed Charkhian

Turkish Journal of Chemistry

In this study, boric acid (BA) is employed as a crosslinking agent to improve the characteristics of two commonly used polymeric films, ethyl cellulose (EC) and polyvinyl alcohol (PVA), for topical drug delivery applications. The developed films are characterized by FTIR spectroscopy and SEM analysis. The results show that the surfaces of the prepared films are even and transparent, except for the BA-modified EC sample. The initial cumulative release for erythromycin (EM) is found to be 0.30 and 0.36 mg/mL for EC and PVA films, which drops to 0.25 and 0.20 mg/mL after BA crosslinking, respectively, after 1 h at …


Synthesis, Antioxidant And Antimicrobial Properties Of Novel Pyridyl-Carbonyl Thiazoles As Dendrodoine Analogs, Zafer Şahi̇n, Sevde Nur Bi̇lteki̇n, Leyla Yurttaş, Şeref Demi̇rayak Jan 2020

Synthesis, Antioxidant And Antimicrobial Properties Of Novel Pyridyl-Carbonyl Thiazoles As Dendrodoine Analogs, Zafer Şahi̇n, Sevde Nur Bi̇lteki̇n, Leyla Yurttaş, Şeref Demi̇rayak

Turkish Journal of Chemistry

Marine compound dendrodoine was first obtained from tunicate species (Dendrodo grossularia). It has a five-membered ring, namely, it is a heterocycle thiadiazole, which is found rarely in natural sources. Following its biological activities, novel analogs have been investigated recently. Synthesis of the analogs for this study is realized with uncommon thiazole closure, including methylene-carbonyl condensation. Structures are elucidated by NMR (1H, 13C) and HRMS spectrums. As an alkaloid derivative, antioxidant properties were evaluated with DPPH and FRAP assays and antimicrobial effect with microdilution method. Among the series, 3bc-3cf showed higher antioxidant activity than those having 3 or 4-pyridyl substituents. There …


Influence Of Annealing On Photoelectric Characteristics And Stability Of Elements Based On Si-Bi$_{2}$Te$_{3-X}$Se$_{X}$, Gurban Ahmadov Jan 2020

Influence Of Annealing On Photoelectric Characteristics And Stability Of Elements Based On Si-Bi$_{2}$Te$_{3-X}$Se$_{X}$, Gurban Ahmadov

Turkish Journal of Physics

In the manufacture of Bi$_{2}$Te$_{3-x}$Se$_{x}$-based elements using two sources of the deposited substance, they were initially annealed at a temperature of 150-200 \textdegree Ñ in a low vacuum. Heat treatment led to a slight increase in short circuit current and an increase in open circuit voltage. When the elements were heated in high vacuum, as well as in atmospheres of argon, nitrogen, hydrogen, helium and other gases, irreversible changes in the characteristics were not detected. Heat treatment of elements at a temperature of 100--150 \textdegree C in oxygen always improves their performance. It is assumed that annealing stimulates the growth …


Stable Anisotropic Single-Layer Of Rete$_2$: A First Principles Prediction, Mehmet Yağmurcukardeş Jan 2020

Stable Anisotropic Single-Layer Of Rete$_2$: A First Principles Prediction, Mehmet Yağmurcukardeş

Turkish Journal of Physics

In order to investigate the structural, vibrational, electronic, and mechanical features of single-layer ReTe$_2$ first-principles calculations are performed. Dynamical stability analyses reveal that single-layer ReTe$_2$ crystallize in a distorted phase while its 1H and 1T phases are dynamically unstable. Raman spectrum calculations show that single-layer distorted phase of ReTe$_2$ exhibits 18 Raman peaks similar to those of ReS$_2$ and ReSe$_2$. Electronically, single-layer ReTe$_2$ is shown to be an indirect gap semiconductor with a suitable band gap for optoelectronic applications. In addition, it is found that the formation of Re-units in the crystal induces anisotropic mechanical parameters. The in-plane stiffness and …