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    Advanced-designed Ru(II) complexes containing phosphinite ligands derived from chiral amino alcohols: Electrochemical behavior, DFT calculations, and biological activity
    (Elsevier Science Sa, 2025) Meric, Nermin; Isik, Ugur; Dauletbakov, Anuar; Zolotareva, Darya; Zazybin, Alexey; Sever, Mehmet Serif; Okumus, Veysi
    We report two phosphinite ligands derived from chiral amino alcohols, and their complexes with ruthenium(II). These compounds were characterized by spectroscopic methods. Then, antimicrobial, antioxidant, and DNA binding activities of the chiral Ru(II)-phosphinite complexes were tested. Complex (1R)-2-{benzyl[(1S)-1(naphthalen-1-yl)ethyl]amino}-1-phenylethyl diphenylphos- phinito[dichloro(eta 6-p-cymene)ruthenium(II)], 7 showed both the highest radical scavenging activity (90.93 +/- 0.98 %) and the highest metal chelating activity (65.45 +/- 1.46 %) at 200.0 mg l-1 concentration. In addition, all of complexes had different rates of binding activity to calf thymus DNA (CT-DNA). Moreover, extensive theoretical and experimental investigations were conducted to gain a more profound understanding of the chemical descriptors and the diverse electronic transitions taking place within the ruthenium complexes, as well as their electrochemical characteristics.
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    Anoxybacillus sp. SO B1-Immobilized Amberlite XAD-16 for Solid-Phase Preconcentration of Cu(II) and Pb(II) and Their Determinations by Flame Atomic Absorption Spectrometry
    (Taylor & Francis Inc, 2015) Oral, Elif Varhan; Ozdemir, Sadin; Dolak, Ibrahim; Okumus, Veysi; Dundar, Abdurrahman; Ziyadanogullari, Berrin; Aksoy, Zehra
    A new method for the determination of Cu(II) and Pb(II) by flame atomic absorption spectrometry (FAAS) after preconcentrating on a column containing Anoxybacillus sp. SO B1-immobilized Amberlite XAD-16 was developed. The functional groups of Anoxybacillus sp. SO B1 immobilized on Amberlite XAD-16 were characterized in KBr tablets by Fourier transform infrared (FT-IR) spectrometry. Various parameters such as pH, amount of the adsorbent, eluent type and volume, and flow rate of the sample solution were studied. The optimum pH values of quantitative sorption for Cu(II) and Pb(II) were found to be pH 7.0 and 5.0 and Cu(II) and Pb(II) ions could be quantitatively eluted with 5.0ml of 1.0mol L-1 HCI and 10.0ml of 0.25mol L-1 HNO3, respectively. Recoveries of Cu(II) and Pb(II) were found to be 100.9 +/- 1.57% and 100.3 +/- 0.49% (N = 5), the limits of detection of Cu(II) and Pb(II) in the determination by FAAS (3s, N = 10) were found to be 0.8 and 1.6 mu g L-1, respectively. The proposed enrichment method was applied for metal ion determination from water samples such as two parts of Tigris River water in Diyarbakir and Elazig, Lake of Hazar in Elazig, and tap water in Diyarbakir. Furthermore, the accuracy of the proposed method was verified by studying the analytical recovery and by analyzing certified reference material (NCS-DC 73350 leaves of poplar).
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    Antioxidant Properties of Cultured Mycelia from Four Pleurotus Species Produced in Submerged Medium
    (Taylor & Francis Inc, 2013) Dundar, Abdurrahman; Okumus, Veysi; Ozdemir, Sadin; Yildiz, Abdunnasir
    The ethanolic extracts of dried cultured mycelia of Pleurotus ostreatus, Pleurotus eryngii, Pleurotus florida, and Pleurotus sajor-caju were analyzed for antioxidant activity in different systems. Tests used are as follows: reducing power, free radical scavenging, superoxide anion radical scavenging, total antioxidant activity, metal chelating activitiy, etc.; total phenolic content was determined. The percentage inhibition of P. ostreatus, P. eryngii, P. florida, and P. sajor-caju at 20 mg/mL concentration on peroxidation in a -carotenelinoleic acid system was 57.19, 60.68, 62.12, and 58.81%, respectively. The reducing power of P. eryngii was higher than the other samples, and its value was 0.86 at 10 mg/mL concentration. P. ostreatus and P. sajor-caju proved to be better at scavenging superoxide anion radicals than the P. eryngii and P. florida. In the scavenging effect of DPPH radical test, P. ostreatus showed the highest activity potential and P. sajor-caju showed the strongest metal chelating capacity.
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    Biological assays and theoretical density functional theory calculations of Rh(I), Ir(III), and Ru(II) complexes of chiral phosphinite ligand
    (Wiley, 2020) Rafikova, Khadichakhan; Binbay, Nil Ertekin; Meric, Nermin; Kerimkulova, Aygul; Zazybin, Alexey; Binbay, Veysel; Okumus, Veysi
    Four metal complexes, IL-OPPh2-Ru-p-cymene (3), IL-OPPh2-Ru-benzene (4), IL-OPPh2-Ir-Cp* (5), IL-OPPh2-Rh-COD (6), have been evaluated for in vitro antioxidant activity such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power activity. Maximum scavenging activity (71.43%) was obtained with IL-OPPh2-Ru-p-cymene, whereas IL-OPPh2-Rh-COD showed the highest reducing power ability. The complexes were also studied for their antimicrobial activity against three Gram-positive and three Gram-negative bacteria. In addition, DNA binding of the complexes was evaluated using calf thymus DNA. Both Ru(II) complexes exhibited good DNA-binding activity while the other complexes did not have any activity. Furthermore, ab initio quantum calculations of four complexes were also carried out using density functional theory to better understand their chemical behaviors.
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    Biological assays, electrochemical behavior, and theoretical DFT calculations of Ru(II) complexes of chiral phosphinite based based on ?-amino alcohols: Transfer hyrogenation of ketones using a HCOOH/ Et3N mixture
    (Elsevier, 2024) Rafikova, Khadichakhan; Meric, Nermin; Binbay, Nil Ertekin; Okumus, Veysi; Sever, M. Serif; Belyankova, Yelizaveta; Tursynbek, Saniya
    Synthesis of two phosphinite ligands based on beta-amino alcohols, in high yields has been demonstrated. When we treated [Ru(arene)(mu-Cl)Cl]2 {arene:p-cymene,benzene} with chelating phosphinite ligands, we obtained neutral Ru(II)-complexes possessing the general formula [Ru(arene)phosphiniteCl2]. The structure of the ligands and complexes was confirmed using analytical and spectroscopic techniques. The quantum chemical calculations were carried out for the ruthenium complexes at the DFT/CAM-B3LYP level of theory in gas phase. The phosphinite complexes were subjected to cyclic voltammetry studies in order to determine the energies of HOMO and LUMO levels and to estimate their electrochemical and some electronic properties. Organic complex -based memory substrates were immobilized using TiO2-modified ITO electrodes, and the memory functions of phosphinite-based organic complexes were verified by chronoamperometry (CA) and open -circuit potential amperometry (OCPA). In the present study, the antioxidant potentials of ruthenium-basedp-cymene and benzene complexes through DPPH radical scavenging, metal chelating, and reducing power activities were also determined. In addition, DNA binding abilities and antimicrobial activities of these complexes against pathogenic bacteria were studied. Finally, the ruthenium complex, (2S)-1-{[(2S)-2-[(diphenylphosphanyl)oxy]propyl][(1R)-1- phenylethyl]amino}propan-2-yldiphenyl phosphinitobis[dichloro(eta 6-benzene)ruthenium(II)] also catalyzed asymmetric transfer hydrogenation of acetophenone with high conversion (up to 99%) and good enantioselectivity (ee up to 89 %), in the existence of formic acid and triethylamine in dichloromethane medium under air atmosphere.
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    Biosorption of 2,4-d, 2,4-DP, and 2,4-DB from aqueous solution by using thermophilic anoxybacillus flavithermus and analysis by high-performance thin layer chromatography: Equilibrium and kinetic studies
    (Wiley, 2012) Ozdemir, Sadin; Bekler, Fatma Matpan; Okumus, Veysi; Dundar, Abdurrahman; Kilinc, Ersin
    In this study, the potential biosorption characteristics of the thermophilic Anoxybacillus flavithermus (A. flavithermus) was investigated for the removal of the chlorophenoxy acid derivates, namely, 2,4-dichlorophenoxy acetic acid (2,4-D), 2,4-dichlorophenoxy propanoic acid (2,4-DP or dichlorprop), and 2,4-dichlorophenoxy butyric acid (2,4-DB). The experiments were performed for the simultaneous biosorption of the studied pesticides. Optimum biosorption conditions were determined as a function of contact time, pH of the solution, amount of biomass, and initial pesticides concentrations. The concentrations of the pesticides in the remaining solutions were simultaneously analyzed by high performance thin layer chromatography. The optimum parameters were found as pH: 4.0 for biosorption medium, 60 min of contact time, 50 mg of bacteria, and 50 mg L-1 of initial pesticides concentrations. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the pesticides by A. flavithermus as biomass. Biosorption of pesticides on to A. flavithermus showed pseudo first-order rate kinetics at different initial concentration of pesticides and different temperatures. The experimental adsorption data were fitted both the Langmuir and Freundlich adsorption models. Fourier-transform Infrared spectroscopy was used to understand the bonding mechanism of pesticides to biosorbent and surface functionality of the biosorbent The highest pesticide uptake was calculated from Langmuir isotherm and found to be 24.15 mg g-1 for 2,4-D. Among the studied pesticides, 2,4-DP showed difference adsorption behavior. According to in your comments the reason of this that 2,4-DP contain an asymmetric carbon atom, which provide a molecular chirality. (C) 2011 American Institute of Chemical Engineers Environ Prog, 2011
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    Biosorption of chlorophenoxy acid herbicides from aqueous solution by using low-cost agricultural wastes
    (Taylor & Francis Inc, 2015) Okumus, Veysi; Celik, K. Serdar; Ozdemir, Sadin; Dundar, Abdurrahman; Kilinc, Ersin
    The potential biosorption abilities of apple shell (AS), orange peel (OP), banana peel (BP), and millet waste (MW) as a bio-waste material to remove 2,4-dichlorophenoxy acetic acid (2,4-D), 2,4-dichlorophenoxy propanoic acid (2,4-DP), and 2,4-dichlorophenoxy butyric acid (2,4-DB) from aqueous solution were investigated in batch condition. Optimum biosorption conditions were determined as a function of contact time, pH of the solution, amount of biomass, and initial pesticide concentrations. The concentrations of the pesticides in the remaining solutions were simultaneously determined by high performance thin layer chromatography. Langmuir and Freundlich models were applied to describe the biosorption isotherm of the pesticides by agricultural wastes. The experimental adsorption data were fitted to Langmuir adsorption models (r(2)>0.99). It was found that adsorption of 2,4-DP was higher for all biosorbent. The highest maximum adsorption capacities of 2,4-DP were found as 40.08, 22.71, 33.26, and 45.45mg/g, respectively, for AS, OP, BP, and MW. Maximum adsorption capacity was obtained for 2,4-D as OP>MW>BP>AS, 2,4-DP as MW>AS>BP>OP, and 2,4-DB as OP>AS>BP>MW. From the results, it can be said that MW was an effective biosorbent for removal of 2,4-DP and OP was an effective biosorbent for removal of 2,4-D and 2,4-DB through the studied pesticides. Optimum biosorption conditions were determined as 60min of contact time, 100mg of biomass, AS at pH 6.0, OP at pH 6.0, MW at pH 7.0, and BP at pH 7.0. FT-IR was employed to understand the surface properties of biosorbents. According to the results, agricultural wastes have high adsorption capacity.
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    Determination of cytotoxic, anticholinesterase, antioxidant and antimicrobial activities of some wild mushroom species
    (Informa Healthcare, 2016) Dundar, Abdurrahman; Okumus, Veysi; Ozdemir, Sadin; Celik, Kadir Serdar; Boğa, Mehmet; Ozcagli, Eren
    In the performed study of methanol extraction of wild edible mushroom species; Agaricus arvensis, Agaricus campestris, Armillaria mellea, Fomes fomentarius, Coprinus micaceus, Coriolus versicolor and Lactarius deliciosus were examined for screening their cytotoxic, anticholinesterase, antioxidant and antimicrobial capacity. Phenolic acid composition of mushrooms was also analysed. L. deliciosus and F. fomentarius were generally showed the highest activities at antioxidant test systems (metal chelating, superoxide anion radical scavenging, total antioxidant, 2,2-diphenyl-1-picrylhydrazyl radical scavenging and reducing power activity tests). The highest activities at antimicrobial activity displayed by A. arvensis and as 18 ± 0.8 against to Staphylococcus aureus. The best IC50 values of mushroom methanol extracts at anticancer activities on HeLa and NRK-52E were 7.09 and 18.23 mg/mL exhibited by C. micaceus and A. campestris, respectively. The highest butyrylcholinesterase activity exhibited by L. deliciosus. Total amount of phenolic acids were found as 1,224.70 mg/kg at L. deliciosus. © 2016 The Author(s). This open access article is distributed under a Creative Commons Attribution (CC-BY) 4.0 license.
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    DNA cleavage properties and synthesis of metallophthalocyanines with 5-methyl-[1,2,4] triazolo [1, 5-a] pyrimidin-7-oxy substituents
    (Taylor & Francis Inc, 2017) Agirtas, M. Salih; Ondes, M. Yusuf; Ozdemir, Sadin; Okumus, Veysi
    The aim of the present study is to perform synthesis of novel metallophthalocyanines (pcs) with high solubility. The synthesis and characterization of 5-methyl-[1, 2, 4] triazolo [1, 5-a] pyrimidin-7-yloxy-substituted zinc, magnesium, and cobalt pcs are reported. These compounds have been characterized using electronic absorption, nuclear magnetic resonance spectroscopy, infrared, elemental analysis and mass spectra. The aggregation investigations carried out in different concentrations indicate that 5-methyl-[1, 2, 4] triazolo [1, 5-a] pyrimidin-7-yloxy-substituted pc complexes do not have any aggregation behavior for the concentration range of 1 x 10(-5) -1 x 10(-6) M in THF. DPPH radical scavenging activity, metal chelating activity, and reducing power of the compounds were evaluated. The DNA gel electrophoresis studies revealed that new phthalonitrile and its metallophthalocyanine compounds cleavaged plasmid DNA (pBR322). Additionally, the ground-state geometries of the complexes were optimized using density functional theory methods at B3LYP/6-31G (d, p) level in order to obtain information about the 3D geometries and electronic structure.
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    Half-sandwich ruthenium(II) and iridium(III) complexes of imidazole based phosphinite ligands: antioxidant and antibacterial activities as well as electrochemical properties
    (Wiley-V C H Verlag Gmbh, 2024) Isik, Ugur; Rafikova, Khadichakhan; Meric, Nermin; Guzel, Remziye; Kerimkulova, Aygul; Akimbek, Arailym; Okumus, Veysi
    Ruthenium(II) and iridium(III) complexes of phosphinites including imidazole moiety were synthesized and characterized by microanalysis, IR, MS, and NMR spectroscopies. Antibacterial activity against Gram-positive and Gram-negative bacterial strains was assessed in all complexes. The highest radical scavenging (72.2 %) was obtained for [3-(3-chloro-2-({[dichloro(eta 6-benzene)ruthenium]diphenylphosphanyl}oxy)propyl)-1-butyl-1H-imidazol-3-ium chloride], 4 at 200 mu g/mL concentration, while [3-(3-chloro-2-({[dichloro(eta 5-pentamethylcyclopentadienyl)-iridium]diphenylphosphanyl}oxy)pro-pyl)-1-butyl-1H-imidazol-3-ium chloride], 6 demonstrated the highest antibacterial activity as 13 mm inhibition zone against E. hirea. Furthermore, optical and electrochemical featured of metal complexes containing imidazole phosphinite were investigated utilizing UV-vis absorption and cyclic voltammetry techniques. Consequently, all complexes can be proposed as metal-based charge convertible phosphinite complexes which may be employed as new generation and synergistic Dye-Sensitized Solar Cell (DSSC) materials. Ruthenium(II) and iridium(III) complexes of phosphinites including imidazole moiety are synthesized and characterized by microanalysis, IR, MS, and NMR spectroscopies. Their antibacterial activity against Gram-positive and Gram-negative bacterial strains is assessed. Furthermore, optical and electrochemical features of the metal complexes are investigated utilizing UV-vis absorption and cyclic voltammetry techniques. image
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    In vitro propagation of Diyarbakir watermelons and comparison of direct-seeded and transplanted watermelon
    (Tubitak Scientific & Technological Research Council Turkey, 2011) Okumus, Veysi; Pirinc, Vedat; Onay, Ahmet; Basaran, Davut
    A rapid protocol using shoot tip explants for micropropagation of Diyarbakir watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai] types Surme, Beyazkis and Karakis was achieved. Shoot tips from 5-day-old in vitro germinated seedlings were cultured on shoot regeneration medium for 3 weeks. The effects of the different concentrations of benzyl adenine (BA) and carbohydrate types on shoot proliferation were examined. The results confirmed that a range of 0.5-1.0 mg/L of BA was almost equally effective in promoting the shoot length of cultures in the 3 genotypes. Sucrose, in the presence of BA, was superior to other carbohydrates for the 3 genotypes studied in terms of the number of proliferated shoots and the average shoot length obtained. The highest percentage of rooting was achieved when medium supplemented with 1.0 mg/L of indole-3-butyric acid (IBA) was used for the 3 genotypes. The highest frequency of acclimatized plantlets for the 3 genotypes was 85%, 85%, and 90%, respectively, in sterile compost, when the shoots of Beyazkis, Karakis, and Surme were rooted in the IBA-supplemented rooting treatments. The Surme genotype produced a significantly higher yield and mean fruit weight than the Beyazkis and Karakis genotypes in both direct-seeded and transplanted watermelons. The main soluble sugar of the experimental types was separated, identified, and quantified using high performance liquid chromatography (H PLC). Fructose was found to be the most abundant sugar and was highly detected in Beyazkis for the seeded watermelon and in Karakis for the transplanted watermelon. This demonstrates that in vitro propagation can be used to produce high quality diploid Diyarbakir watermelon for use in breeding lines.
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    Isolation of a thermophilic Anoxybacillus flavithermus sp nov and production of thermostable ?-amylase under solid-state fermentation (SSF)
    (Bmc, 2012) Ozdemir, Sadin; Matpan, Fatma; Okumus, Veysi; Dundar, Abdurrahman; Ulutas, Mehmet Sefa; Kumru, Mert
    A new bacteria was isolated from hot-spring water of Gazligol, Afyonkarahisar in Turkey. Based on morphological and biochemical tests and 16S rRNA gene sequence analysis, the isolate belonged to the Anoxybacillus flavithermus species which has 99% similarity with the bacterium DNA. The production of alpha-amylase by thermophilic Anoxybacillus flavithermus was investigated under solid-state fermentation by using some agricultural waste as substrates. Solid substrates such as rice husk, banana husk, millet, water melon husk, lentil bran, wheat bran and maize oil cake were studied for enzyme production. Of these, rice husk was proved as the best substrate for alpha-amylase production (1,271 U/mg). The maximum alpha-amylase production was observed as 1,803 U/mg at 72 h, 1,000 mu m particle size, 70% initial moisture content (w/v), and 40% inoculum level (v/w). Among the various nitrogen sources tested, 1% peptone (3,170 U/mg) was found to be the best nitrogen source for alpha-amylase production. As additional carbon sources, 1% starch (2,364 U/mg) enhanced alpha-amylase production. The optimum temperature for the activity of alpha-amylase was found to be 70A degrees C. The enzyme was optimally active at pH 6.0 and stable in the pH range of 6.0-8.0.
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    Metallo phthalocyanines bearing (2-((2-hydroxyethyl) (p-tolyl)amino)ethoxy) and (2-((2-phenoxyethyl) (p-tolyl)amino)ethoxy)phthalonitrile substituents: Synthesis, characterization, aggregation behavior, antioxidant and antibacterial activity
    (Elsevier Science Sa, 2014) Celebi, Metin; Agirtas, M. Salih; Okumus, Veysi; Ozdemir, Sadin
    The novel phthalonitrile derivatives bearing (2-((2-hydroxyethyl)(p-tolyl)amino)ethoxy) and (2-((2-phenoxyethyl)(p-tolyl)amino)ethoxy)phthalonitrile substituents at peripheral position were prepared by a nucleophilic displacement reaction. Cyclotetramerization of these phthalonitrile derivatives in the presence of corresponding metal salts gave the new metallophthalocyanines. The novel compounds were characterized by using various spectroscopic data. The aggregation investigations carried out in different concentrations indicate that phthalocyanine compounds do not have any aggregation behavior for the concentration range of 10(-4)-10(-6) M in tetrahydrofuran. In vitro three antioxidant test methods, namely diphenylpicrylhydrazyl radical scavenging activity, metal chelating activity and reducing power were used to determine the antioxidant activity of compounds. Compounds were analyzed for their antibacterial activity against some bacteria by using the disk-diffusion method. (C) 2014 Elsevier B.V. All rights reserved.
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    Metallo Phthalocyanines bearing 2-Isopropyl-6-methylpyrimidin-4-yloxy Substituents: Synthesis, Characterization, Aggregation Behavior, Antioxidant and Antibacterial Activity, and Electronic Properties
    (Wiley-V C H Verlag Gmbh, 2014) Agirtas, M. Salih; Dede, Emrah; Gumus, Selcuk; Dundar, Abdurrahman; Okumus, Veysi
    A novel phthalonitrile derivative bearing 2-isopropyl-6-methylpyrimidin-4-yloxy substituents at peripheral positions was synthesized by a nucleophilic substitution reaction. Metallophthalocyanines were obtained from the reaction of the novel phthalonitrile with metal Zn, Cu, Co, and Ni salts. The characterization of the compounds was performed using elemental analysis as well as UV/Vis, FT-IR, and H-1-NMR spectroscopy. The aggregation behaviors of phthalocyanine complexes were also investigated. These metallophthalocyanines do not show any aggregation behavior between 10 (4)-10 (6) M concentration range in THF. The antioxidant activities of the synthesized compounds were evaluated using three different tests: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, metal chelating activity, and reducing power assays. All the compounds exhibited various antioxidant activities. In addition, antimicrobial activity of the compounds was tested over four gram positive and two gram negative bacteria. Moreover, the ground-state geometries of the complexes were optimized using density functional theory (DFT) methods at B3LYP/6-31G(d,p) level in order to obtain information about the 3D arrangements and electronic structure.
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    New water soluble phenoxy phenyl diazenyl benzoic acid substituted phthalocyanine derivatives: Synthesis, antioxidant activities, atypical aggregation behavior and electronic properties
    (Elsevier Sci Ltd, 2013) Agirtas, M. Salih; Celebi, Metin; Gumus, Selcuk; Ozdemir, Sadin; Okumus, Veysi
    Novel substituted phthalonitrile derivatives were obtained by the reaction of 2-(4-hydroxyphenylazo) benzoic acid and 4,5-dichloro-1,2-dicyanobenzene, or 4-nitrophthalonitrile. Peripherally phenoxy phenyl diazenyl benzoic acid substituted zinc (II) phthalocyanine complexes, and their sodium salts were synthesized and characterized for the first time. The newly synthesized phthalocyanine complexes show excellent solubility in water. The aggregation investigations carried out in different concentrations indicate that phenoxy phenyl diazenyl benzoic acid-substituted phthalocyanine compounds do not have any aggregation behavior for the concentration range of 7.00 x 10(-5)-4.38 x 10(-6) M in DMF. The antioxidant activities of DMF solution of compounds were analyzed through radical scavenging, and chelating ability to Fe2+ cation. Additionally, new compounds did not show any antibacterial activity against some selected bacteria cultures. Moreover, the ground-state geometries of the complexes were optimized using density functional theory (DFT) methods at B3LYP/6-31G(d,p) level in order to obtain information about the 3D geometries and electronic structure. (C) 2013 Elsevier Ltd. All rights reserved.
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    Novel Cobalt(II), Zinc(II) Phthalocyanines Bearing Discrete Substituents: Synthesis, Characterization, Aggregation Behavior, Electrochemical Properties, and Antioxidant Activity
    (Taylor & Francis Inc, 2014) Agirtas, M. Salih; Cabir, Beyza; Dundar, Abdurrahman; Okumus, Veysi; Ceyhan, Gokhan
    A new phthalonitrile derivative bearing 3,4,5-trimethoxy- benzyloxy and chloro-substituents at peripheral position was prepared by a nucleophilic displacement reaction. Cyclotetramerization of phthalonitrile derivative in dimethylsulfoxide (DMSO) gave the metallophthalocyanines. Novel Co(II), Zn(II) phthalocyanines (Pcs) were obtained from the reaction 4-[(3,4,5-trimethoxybenzyloxy]-5-chlorophthalonitrile and metal salts. The novel compounds have been characterized by using elemental analysis, UV-Vis, FTIR, H-1-NMR spectral data. The aggregation behaviors of Co(II), Zn(II) Pcs were also investigated. These metallophthalocyanines do not show any aggregation behavior between 1.2 x 10(-5) and 4.0 x 10(-6) M concentration range in DMF. The antioxidant activities of Pcs were investigated antioxidant assays such as free radical scavenging ability of 1,1-diphenyl-2-picryl-hydrazyl (DPPH) and ferrous ion chelating ability. Furthermore, the redox properties of the Pcs complexes were investigated by using cyclic voltammetry.
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    Pleurotus eryngii immobilized Amberlite XAD-16 as a abstract insert solid-phase biosorbent for preconcentrations of Cd2+ and Co2+ and their determination by ICP-OES (vol 99, pg 502, 2012)
    (Elsevier Science Bv, 2013) Ozdemir, Sadin; Okumus, Veysi; Kilinc, Ersin; Bilgetekin, Havin; Dundar, Abdurrahman; Ziyadanogullari, Berrin
    [Abstract Not Available]
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    Preconcentration with Bacillus subtilis-Immobilized Amberlite XAD-16: Determination of Cu2+ and Ni2+ in River, Soil, and Vegetable Samples
    (Taylor & Francis Inc, 2015) Okumus, Veysi; Ozdemir, Sadin; Kilinc, Ersin; Dundar, Abdurrahman; Yuksel, Uyan; Baysal, Zubeyde
    Solid-phase extraction (SPE) method was developed for the preconcentration of Cu2+ and Ni2+ before their determination by inductively coupled plasma optical emission spectrometry (ICP-OES). Bacillus subtilis-immobilized Amberlite XAD-16 was used as biosorbent. Effects of critical parameters such as pH, flow rate of samples, amount of Amberlite XAD-16 and biosorbent, sample volume, eluent type, and volume and concentration of eluent on column preconcentration of Cu2+ and Ni2+ were optimized. Applicability of the method was validated through the analysis of the certified reference tea sample (NCS ZC73014). Sensitivity of ICP-OES was improved by 36.4-fold for Cu2+ and 38.0-fold for Ni2+ by SPE-ICP-OES method. Limit of quantitation (LOQ) was found to be 0.7 and 1.1ng/ml for Cu2+ and Ni2+, respectively. Concentrations of Cu2+ and Ni2+ were determined by ICP-OES after application of developed method. Relative standard deviations (RSDs) were lower than 4.9% for Cu2+ and 7.9% for Ni2+. The Tigris River that irrigates a large agricultural part of Southeast Turkey is polluted by domestic and industrial wastes. Concentrations of Cu2+ and Ni2+ were determined in water, soil, and some edible vegetables as a biomonitor for heavy metal pollution.
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    Preparation and spectral studies of boronate ester modified magnetite iron nanoparticles (Fe3O4@APTES-B) as a new type of biological agents
    (Elsevier, 2022) Kilic, Ahmet; Karatas, M. Emin; Beyazsakal, Levent; Okumus, Veysi
    We have designed two novel magnetite targeting biological agents (Fe3O4@APTES-B-(1,B-2)) with a core of Fe3O4 and a shell made of boronate esters (APTES-B) to improve the biological effectiveness of magnetite Fe3O4 nanoparticles (MNPs). Initially, two boronate esters (B-1) and (B-2) have been prepared by 3,4dihydroxybenzaldehyde and phenylboronic acid and/or butylboronic acid using a Dean-Stark apparatus to remove the water formed during the esterification reactions. Then, the APTES-B-1,(2) compounds have been synthesized via boronate esters and APTES in the presence of 1-2 drops of formic acid as catalyst. Finally, magnetite Fe3O4 NPs were added to APTES-B-1,B-2 compounds to afford boronate ester modified magnetite iron nanoparticles (Fe3O4@APTES-B-1,B-2) at ambient temperature, respectively. The boronate esters (B-1) and (B-2), APTES-B-1,B-2 compounds, and boronate ester modified magnetite iron nanoparticles (Fe3O4@APTES-B-1,B-2) were characterized using a combination of NMR (H-1, C-13, and B-11), FT-IR, UV-Vis, LC-MS/MS, elemental analysis (CHN), XRD, SEM-EDX, EDX mapping, BET, and TG-DTA). Then, the antioxidant, antimicrobial and DNA binding activities of newly synthesized target compounds were tested. These results suggest that all compounds are also one of the propitious drug candidates and are worthy of further investigation. (C) 2022 Elsevier B.V. All rights reserved.
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    Preparation and spectroscopic properties of bioactive 1, 2, 3-triazole-linked boronate esters for use in antioxidant, antimicrobial, and DNA binding studies
    (Elsevier Science Sa, 2023) Kilic, Ahmet; Alshhab, Anas; Okumus, Veysi
    In this article, the preparation, spectral evaluation, and biological studies of bioactive 1, 2, 3-triazole-linked boronate esters are reported. The bioactive 1, 2, 3-triazole group linked-boronate esters have been designed and obtained by azido-functionalized boronate ester with different alkyne molecules via click chemistry approach under mild conditions. The prepared boronate esters (B 1-5 ) were characterized us-ing NMR ( 1 H, 13 C, and 11 B) spectra, FT-IR spectra, UV-Vis spectra, LC-MS/MS spectra, elemental analy-sis, and melting point measurement techniques. After all structures of synthesized boronate esters were characterized in detail, the antimicrobial (antioxidant and antibacterial) and DNA binding properties of newly prepared boronate esters were investigated. The bioactive 1, 2, 3-triazole-linked boronate ester (B 5 ) showed the highest radical scavenging (71.59 +/- 1.85%) and reducing power activity (0.476 +/- 0.01) at 200.0 mu g/mL concentration. According to the method of reducing power activity, the compound (B 5 ) exhibited the strongest activity with 0.476 +/- 0.014. The anti-bacterial activity of all boronate esters (B 1-5 ) was determined with four pathogenic bacteria. It was determined that only the 1, 2, 3-triazole-linked boronate ester (B 5 ) showed low activity against two bacteria (8 mm for S. aureus and 10 mm for E. hirae), while other boronate esters were found to have no activity. According to electrophoresis results using calf thymus DNA (CT-DNA), 1, 2, 3-triazole-linked boronate esters (B 3-5 ) were determined to have DNA binding activity. (c) 2023 Elsevier B.V. All rights reserved.