Tıbbi Hizmetler ve Teknikler Bölümü Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12514/159

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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.
Association with Leptin Gene c.-2548 G > A Polymorphism, Serum Leptin Levels, and Body Mass Index in Turkish Obese Patients
(HUMANA PRESS INC, 2013) Demir, Cemil; Say Şahin, Deniz; Demir, Cemil; Çelik, M. Murat; Çelik, Mustafa; Uçar, Edip; Güneşaçar, Ramazan
Leptin is a protein hormone which plays a critical role in the regulation of both body-weight through reducing food intake and stimulating energy expenditure. Several polymorphisms in leptin gene (LEP), which encodes for leptin, have been described. However, its association with obesity is still controversial. Therefore, in the present study, we aimed to investigate whether LEP c.-2548 G > A polymorphism was associated with serum leptin levels, lipid parameters, and body mass index in Turkish obese patients. Forty-seven obese patients and 48 healthy individuals were included in the study. Blood samples were collected for DNA extraction. LEP c.-2548 G > A polymorphism were detected using polymerase chain reaction-restriction fragment length polymorphism technique. Serum leptin levels and lipid parameters were measured by ELISA and enzyme colorimetric assay techniques, respectively. GA or AA genotypes and A allele carrier frequencies of the c.-2548 G > A polymorphism in the LEP were higher in obese (38.3, 34.0 and 72.3 %) when compared with controls (14.6, 12.5, and 27.1 %; p = 0.011, 0.016, and 0.002, respectively). On the other hand, AA or AG genotypes were also related to increased serum leptin levels (p < 0.001) and body mass index (p < 0.0001). All these consequences showed that LEP -2548 AA or AG genotypes are important predictors for increased levels of leptin and BMI in Turkish obese patients and it may be a useful marker for obesity risk in our population.
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.
Covalent immobilization of benzoylformate decarboxylase from Pseudomonas putida on magnetic epoxy support and its carboligation reactivity
(Elsevier, 2014) Tural; Tarhan; Tural, Bilsen; Tuba; Servet
Epoxy attached magnetic nanoparticles were prepared and used as solid support for covalent immobi-lization and stabilization of benzoylformate decarboxylase (BFD, E.C. 4.1.1.7) fromPseudomonas putida.A three-step immobilization/stabilization procedure is applied. The enzyme is firstly covalently immobi-lized under mild experimental conditions (e.g. pH 7.0, no added MgSO4and 20◦C). Secondly, the enzymeis immobilized under more drastic conditions (higher pH values, higher ionic strengths, etc.) to facili-tate an increase in effective concentration of the enzyme on the support near the epoxide reactive sites.Thirdly, the remaining epoxy groups are blocked to stop any additional interaction between the enzymeand the support. With more drastic conditions, the loading of enzyme can be increased from 1.25 to6.70 mg enzyme per gram of support. The covalently bounded enzyme was characterized in terms ofits activity and stability for the formation of (S)-2-hydroxypropiophenone (2-HPP). The activity of theimmobilized BFD was determined to be 53.0% related to the activity of the free enzyme. The immobilizedbiocatalyst retained 95% of its original activity after five reaction cycles.
Cyclophosphamide induced oxidative stress, lipid per oxidation, apoptosis and histopathological changes in rats: Protective role of boron
(Elsevier, 2020) Cengiz, Mustafa; Şahintürk, Varol; Cetik Yildiz, Songul; Kurcanay Şahin, İlknur; Bilici, Namık; Onur Yaman, Suzan; Altuner, Yılmaz; Appak-Baskoy, Sıla; Ayhanci, Adnan
Background Cyclophosphamide (CP) is an alkylating chemotherapeutic drug used in the treatment of many types of cancer. However, as with other chemotherapeutic drugs, the use of CP is limited by the damage to healthy tissues such as testes, bladder and liver as well as cancerous tissue. Boron (B) is a trace element with many biological properties such as antioxidant, anti-apoptotic and anti-lipid per oxidation. Methods This current study aims to determine protective effects of B on CP induced testicular toxicity. The rats were divided into 4 groups (control, CP, B and B plus CP groups). The testes of experimental animals were taken for histological, apoptotic markers and biochemical analysis. Results The damage to some seminifer tubules, loss of typical appearance, thinning of seminifer epithelium and relative enlargement of the tubule lumen were watched in testis of the group that administrated CP. Moreover, Bcl-2, TAC and GSH levels decreased while TOC, OSI, MDA, Bax and Caspase-3 levels increased. On the other hand, pretreatment limited to B in the B plus CP group, testicular tissue improved. In addition, Bcl-2, GSH, TAC levels increased, Bax, MDA, TOC, OSI and caspase-3 levels decreased. Conclusion B significantly reduced testicular lipid per-oxidation and strengthened antioxidant defenses. Our results showed that pre-treatment B can protect rat testis against CP-induced testicular damage owing to its anti-lipid per oxidation, anti-oxidant and anti-apoptotic properties.
Determination of hydroxymethylfurfural in Turkish honeys, pekmez (grape molasses), and jam samples by high-performance liquid chromatography with diode array detection
(Wiley Online Library, 2022) Umaz, Adil; Aydin, Firat; Umaz, Adil; Kılınc, Ersin; Arslan, Yasin; aydin, Isil
Hydroxymethylfurfural (HMF) is a chemical contaminant that is not naturally present in carbohydrate-containing food samples. The HMF amounts were changed between 4.8 and 214.1 mg/kg in honey; between 7.8 and 204.0 mg/kg in pekmez (grape molasses); between 5.9 and 22.4 mg/kg in strawberry jam; between 6.0 and 65.4 mg/kg in apricot jam; and between 9.2 and 55.9 mg/kg in cherry found by HPLC. The linear calibration plot of HMF was ranged from 0.05 to 10.0 mu g/ml. The correlation coefficient was found to be 0.99997. LOD and LOQ values were found to be 12.0 and 40.0 ng/ml, respectively. According to the experimental results, HMF amounts of four honey samples, three pekmez (grape molasses) samples, one apricot jam, and one cherry jam for investigated samples were found to be higher than the permission amount of Turkish Food Codex. Novelty impact statement Based on experimental results in this study, if the honey is in a transparent package such as a glass, it should be stored in a dark environment. It would be healthier to prefer molasses produced by reliable brands at low temperatures under vacuum instead of molasses made with traditional methods in open boilers. Generally, since jams with high HMF amount have an overcooked or even burnt flavor, this is an extremely negative situation for consumers.
Determination of zinc in dried nuts by slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS) with citric acid-coated magnetic nanoparticle (CAMNP) based solid phase extraction (SPE)
(Taylor & Francis inc, 2025) Umaz, Adil; Umaz, Adil; Aydin, Isil; Aydin, Firat
This study reports a sensitive method for trace zinc using slotted quartz tube-flame atomic absorption spectrometry (SQT-FAAS) with citric acid-coated magnetic nanoparticle-solid phase extraction (CAMNP-SPE). To increase the efficiency, we univariately optimized the pH, buffer volume, CAMNP mass, eluent concentration and volume, mixing type and time, temperature, and interaction time. The study identified the limits of detection and quantification values for CAMNP-SPE-SQT-FAAS under the specified optimum conditions to be 12.30 and 41.00 mu g L-1, respectively. The newly developed method improved the detection power of traditional FAAS by 13.25 times. The findings of this study report a sensitive and accurate method to determine trace zinc in complex matrices.
Development of Armillae mellea immobilized nanodiamond for the preconcentrations of Cr(III), Hg(II) and Zn(II)
(Analytical Biochemistry, 2021) Kılınç, Ersin; Ozdemir, Sadin; Şen, Fatih; Soylak, Mustafa
In this study, we present an environmental friend and easy procedure for simultaneous preconcentration of Cr(III), Hg(II) and Zn(II) by solid-phase extraction before their determination by inductively coupled plasma optical emission spectrometry. Armillae mellea immobilized nanodiamond was used as sorbent. During the study, critical parameters influencing the extraction performance were investigated in detail. The best parameters were found as pH 5.0, 2.0 mL min−1 of flow rate, 200 mg of Armillae mellea, 300 mL of sample volume. LOD values were found as 0.025, 0.13 and 0.038 ng mL−1, respectively for Cr(III), Hg(II) and Zn(II). By applying the developed procedure, sensitivities of ICP-OES were improved for 60 fold for Cr(III), Hg(II) and Zn(II). Their concentrations in different food samples were measured after microwave digestion and solid-phase extraction.
Ecofriendly/Rapid Synthesis of Silver Nanoparticles Using Extract of Waste Parts of Artichoke (Cynara scolymus L.) and Evaluation of their Cytotoxic and Antibacterial Activities
(Hindawi, 2021) Keskin, Cumali; Baran, Ayşe; Baran, Mehmet Fırat; Irtegun Kandemir, Sevgi; Valiyeva, Mahbuba; Mehraliyeva, Sevil; Khalilov, Rovshan; Eftekhari, Aziz
Recycling wastes and providing their use in useful fields attract attention every day. In our study, with the extract prepared from the parts of the Cynara scolymus L. (artichoke) plant that is not suitable for human consumption, silver nanoparticles were easily synthesized in an ec-friendly, energy-free way. Characterization of the obtained nanoparticles was done with a UV-visible spectrophotometer (UV-Vis.), fourier transform infrared spectroscopy (FTIR), X-ray diffraction diffractometer (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), and zeta potential analysis data. In these data, it was determined that AgNPs have a maximum absorbance at 458.8 nm wavelength, a crystal nanosize of 28.78 nm, and a spherical appearance. The zeta potential of (-) 16.9 mV indicates that silver nanoparticles exhibit a stable structure. Particles show antimicrobial effects on pathogenic species at concentrations of 0.03-0.25 μg/ml, and it was determined by using the minimum inhibition concentration (MIC) microdilution method. By examining their cytotoxic effects on U118, CaCo-2, and Skov-3 cancer cell lines and healthy HDF cell lines by the MTT method, concentrations of inhibitive effects on survival were determined.
Economic fast synthesis of olive leaf extract and silver nanoparticles and biomedical applications
(Taylor & Francis Online, 2021) Keskin, Cumali; Aktepe, Necmettin; Baran, Ayşe; Baran, Mehmet Fırat; Aktepe, Necmettin; Yavuz, Ömer; İrtegun Kandemir, Sevgi
In this study, silver nanoparticles (AgNPs) were synthesized economically and simply using an environmentally friendly method with the extract obtained from agricultural waste olive leaves. AgNPs synthesized according to the analysis data were determined to have maximum absorbance at 433.5 nm wavelength, spherical appearance, 7.2 nm crystal nano size and -19.9 mV zeta potential. It was determined by the microdilution method with Minimum Inhibition Concentration (MIC) that AgNPs exert a suppressive effect on the growth of pathogen gram-negative, positive bacteria and yeast at very low concentrations. The cytotoxic effects of the particles were investigated on healthy cell lines (HDF) and cancerous cell lines (U118, CaCo-2, Skov-3). AgNPs showed up to 70% suppression in cancer cell lines.
Endohelminth Fauna of Teleost Fishes from Coasts of Şile Region of the Black Sea
(HELMINTHOLOGIA, 2021) Oğuz, Mehmet Cemal; Oğuz, Mehmet Cemal
A total of 508 fish specimens belonging to 19 species collected in the coast of Şile region of the Black sea were examined to detect the presence of endohelminths. Of this, 357 (70.27%) were found to be infected with parasites. 15 distinct helminths species were recovered including four species of nematodes, seven digenean species, one species of cestodes and three species of acanthocephalans. It was also determined that the species of nematode Hysterothylacium aduncum was the most common parasite and the most diverse endohelminth fauna was found in Gobius niger and Solea vulgaris, with five species. Furthermore, it should be noted that Capillaria gracilis is reported for the first time from the Turkish coasts. The infection rates, hosts, and parasites are listed in this paper.
Evaluation as time-dependent of pesticides applied in pre-harvest period of grown vegetables: removal of pesticide residues in the vegetables
(Taylor & Francis Online, 2022) Umaz, Adil; Umaz, Adil; Pirinc, Vedat; Aydin, Firat
Pesticide use has benefits such as increasing the quality and amount of food required to sustain the human population. However, its harmful effects on the environment and human health are of great concern. The aim of this study was to evaluate concentrations as timedependent of the pesticide and the removal of pesticide residues in vegetable samples with the aid of the QuEChERS 2007.01 procedure. The analytical method has been validated according to SANTE/12682/2019. Good linearity (2.5–100 ng/mL, R2 > 0.99) was observed, and the recovery yields ranged from 94.76% to 104.03%, repeatability (RSDr) ranged from 2.33% to 4.59% and reproducibility (RSDwR) ranged from 4.06% to 8.40%. LOD and LOQ values were determined to be 3.00 ng/g and 10.00 ng/g, respectively. The grown tomato, eggplant and cucumber samples were sprayed with drugs against pests and diseases. Imidacloprid in the grown tomato, cucumber and eggplant samples was determined to be 0.026, 0.186 and 0.096 mg/kg, respectively. Trifloxystrobin was determined to be 0.102, 0.129 and 0.063 mg/kg, respectively. It was determined that pesticide residue in vegetable samples decreases by washing and peeling but does not disappear completely. The peeling process was determined to be more effective than washing. The concentration of pesticide residues in the shell part was found to be hight than in the whole product. Thus, it is important to consume vegetables with their skin peeled and to consume the unpeeled ones by washing them with water at least.
Isolation and Molecular Characterization of Methicillin-Resistant Staphylococci from Horses, Personnel and Environmental Sites at an Equine Hospital in Turkey
(JAPAN SOC VET SCI, 2012) Demir, Cemil; Turkyilmaz, Suheyla; Yilmaz, Mehmet Ali; Erdem, Zeynep; Demir, Cemil
The present study was carried out to assess the frequency of methicillin-resistant staphylococci (MRS) among racehorses (n=209) and veterinary personnel (n=13) as well as environmental surfaces (n=14) at an equine hospital in Adana, Turkey. In addition, species distribution, antimicrobial susceptibility, resistance genes, staphylococcal chromosomal cassette mec (SCCmec) type and clonality of these isolates were also investigated. MRS were identified by 16S rRNA sequencing, and typed by pulsed-field gel electrophoresis (PFGE). As a result, MRS was isolated in horses (48.3%), clinic staff (92.3%) and environmental samples (71.4%). Of the 123 MRS isolates, 118 isolates were identified as Staphylococcus lentus, and the remaining ones were found to be S. sciuri (n=3), S. intermedius (n=1) and S. fleuretti (n=1). All isolates were found to be susceptible against vancomycin, quinupristin-dalfopristin and rifampicin. Additionally, single or various combinations of resistance genes were detected among MRS isolates. SCCmec type II was identified in all isolates. Similar PFGE patterns were observed among MRS isolated from horses, humans, and environmental samples. Since MRS were concurrently isolated from horses and humans it is suggested that cross-transmission of MRS between horses and humans might occur. However, it cannot be ruled out that transmission is human to animal or animal to human.
Mononuclear Complexes Based on Pyrimidine Ring Azo Schiff-Base Ligand: Synthesis, Characterization, Antioxidant, Antibacterial, and Thermal Investigations
(WILEY-V C H VERLAG GMBH, 2014) Gulcan, Mehmet; Ozdemir, Sadin; Dundar, Abdurrahman; Ispir, Esin; Kurtoglu, Mukerrem
Six transition metal(II) complexes with the heterocyclic ligand HL (1), [CuL2]center dot H2O (2), [NiL2]center dot 3H(2)O (3), [CoL2]center dot 3H(2)O (4), [MnL2]center dot 3H(2)O (5), [ZnL2]center dot 2H(2)O (6), [PdLOAc]center dot H2O (7) [HL = 5-benzoyl-1-((E)-(2-hydroxy-5-((E)-phenyldiazenyl)benzylidene)amino)-4-phenylpyrimidin-2(1H)-one] were synthesized. The features of the azo Schiff bases were assigned from microanalytical, spectroscopic (IR, UV/Vis., H-1- and C-13 NMR, API-ES mass), magnetic, and molar conductivity measurements at room temperature as well as thermal analysis. The electronic absorption spectroscopy and magnetic susceptibility measurements of the complexes indicate square pyramidal arrangement for Pd-II and octahedral environment for all the other complexes. The azo Schiff base HL acts as a monobasic tridentate ligand, which commonly coordinates through the oxygen atoms of the phenol OH and the pyrimidine one group, and the nitrogen atom of the azomethine group. The thermal behaviors of the ligand and its metal complexes were studied using thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The metal complexes proved to be more thermally stable than the ligand; they decomposed at 10-30 degrees C higher temperatures. Antioxidant properties of the ligand and its metal complexes (DPPH free radical scavenging, ferrous chelating and reducing power activities) were tested. Antimicrobial activities were studied with gram-positive bacteria, which included Bacillus subtilis and Staphylococcus aureus, whereas Escherichia coli and Pseudomonas aeruginosa represented gram negative bacteria.
Preparation, spectral studies, theoretical, electrochemical and antibacterial investigation of a new Schiff base and its some metal complexes
(ELSEVIER SCIENCE BV, 2014) Ilhan, S.; Baykara, H.; Seyitoglu, M. S.; Levent, A.; Ozdemir, S.; Dundar, A.; Oztomsuk, A.; Cornejo, M. H.
A new Schiff base ligand, 1,6-Bis(2-(5-bromo-2-hydroxybenzylideneamino)-4-chlorophenoxy)hexane was synthesized. Some Schiff metal complexes of the new Schiff base were prepared by the reaction of some metal salts and the Schiff base. The complexes are non-electrolytes as shown by their molar conductivities (Lambda M). The structures of metal complexes are proposed from elemental analysis, FT-IR, UV-vis, magnetic susceptibility measurements, molar conductivity measurements, mass spectra and thermal gravimetric analysis. In addition theoretical H-1 NMR, HOMO-LUMO studies of the ligand; antimicrobial and cyclic voltammetric studies of the compounds were also carried out. In this study antioxidant and antibacterial activities of the compounds were examined via in vitro methods. (C) 2014 Elsevier B.V. All rights reserved.
Presence of Biofilm and Adhesin Genes in Staphylococcus aureus Strains Taken from Chronic Wound Infections and their Genotypic and Phenotypic Antimicrobial Sensitivity Patterns
(Photodiagnosis and Photodynamic Therapy, 2020) Demir, Cemil; Demirci, Mehmet; Yigin, Akin; Bahar Tokman, Hrisi; Çetik Yıldız, Songul
The aim of this study was to investigate some biofilm (icaA, icaD and bap) and some adhesion (clfA, fnbA, cna) genes, and also evaluate the phenotypic and genotypic antimicrobial resistance patterns of Staphylococcus aureus strains isolated from wound samples in Mardin, Turkey. A total of 220 wound samples were studied. The biofilm forming ability and resistance pattern for eleven antimicrobial agents were investigated by conventional and multiplex PCR methods. S. aureus was isolated from 112 (50.9%) of 220 wound samples. Moreover, biofilm production was found in 79 (70.5%) of the 112 S. aureus isolates. 97 (86.6%) strains of all isolates were positive for icaA and icaD, and 15 (13.4%) for bap. The adhesin genes, cna, fnbA and clfA were detected in 98 (87.5%), 87 (77.7%), and 75 (66.9%) strains, respectively. The numbers of MSSA and MRSA carrying antimicrobial resistance genes were 19 (16.96%) and 32 (28.57%) for blaZ, 9 (8.04%) and 17 (15.18%) for tetK, 6 (5.36%) and 14 (12.5%) for ermC, 2 (1.79%) and 7 (6.25%) for tetM, 0 (0%) and 5 (4.46%) for mecA, 2 (1.79%) and 4 (3.57%) for ermA, 1 (0.89%) and 2 (1.79 %) for both tetK and tetM, respectively. Our findings indicate that multiplex PCR is a reliable method for identifying biofilm and adhesin producing S. aureus. Our data also provided a nationwide surveillance of the antimicrobial resistance gene profiles of S. aureus for the accurate treatment of patients and to control the dissemination of the resistance genes.
Removal of the Anionic Dye Reactive Orange 16 by Chitosan/Tripolyphosphate/Mushroom
(Chemical Engineering and Technology, 2021) Yıldırım, Ayfer
The green composite chitosan/tripolyphosphate/mushroom (C-TPP-PEE) was synthesized and evaluated for its adsorption performance of the dye Reactive Orange 16 (RO16), by using the batch technique. Fourier-transform infrared spectroscopy, thermogravimetric analysis, and field emission scanning electron microscopy were employed to characterize the C-TPP-PEE. The maximum adsorption capacity of the RO16 dye for batch adsorption was determined as 736 mg g−1. The experimental kinetic data at equilibrium was found to be best fitted to the pseudo-second-order kinetic model. The results showed that the adsorption isotherm was best correlated to the Langmuir model. The thermodynamic data indicated that the adsorption process was spontaneous, favorable, and endothermic.
Selective preconcentration of Lanthanum(III) by Coriolus versicolor immobilised on Amberlite XAD-4 and its determination by ICP-OES
(TAYLOR & FRANCIS LTD, 2014) Ozdemir, Sadin; Okumus, Veysi; Dundar, Abdurrahman; Celik, Kadir Serdar; Yuksel, Uyan; Kilinc, Ersin
Coriolus versicolor, a wood fungus, was immobilised on Amberlite XAD-4 and used as solid-phase biosorbent for preconcentrations of rare earth elements. La(III), Th(IV), U(IV) and Ce(III) were subjected to solid-phase extraction procedure. We observed that La(III) was selectively preconcentrated, while other ions remained in solution at pH 6.0. 5.0mL of 1.0molL(-1) HCl was used to elaute La(III) from column. 250mg of C. versicolor loaded on 1000mg of XAD-4 was optimised as solid-phase matrix. Concentrations of ions in solutions were determined by inductively coupled plasma- optical emission spectrometry (ICP-OES). The calibration plot after preconcentration was linear in the range from 1.0 to 50.0ngmL(-1) for La(III). Limit of detection was found as 0.27ngmL(-1) for La(III) by SPE method. Relative standard deviation was found lower than 6.7% for 1.0ngmL(-1) of La(III) solution (n=10). The sensitivity of ICP-OES was improved by a factor of 46.8. The applicability of the method was validated through the analysis of certified reference samples of tea (NCS ZC-73014) and spinach (NCS ZC-73013).
Synthesis and antioxidant, aggregation, and electronic properties of 6-tert-butyl-1,4-benzodioxine substituted phthalocyanines
(Turkish Journal of Chemistry, 2018) Dündar, Abdurrahman; Cabir, Beyza; Gümüş, Selçuk; Özdemir, Sadin; Dündar, Abdurrahman
As a starting material, 7-tert-butyldibenzo [b,e] [1,4] dioxine-2,3-dicarbonitrile was prepared by the reac- tion of 4-tert-butylcatechol with 4,5-dichlorophthalonitrile. Metallophthalocyanine complexes ( 4 { 7 ) were obtained by cyclotetramerization of 7-tert-butyldibenzo [b,e] [1,4] dioxine-2,3-dicarbonitrile. All compounds were characterized by elemental analysis and other spectroscopic methods (IR, UV/Vis, and 1 H NMR). Phthalocyanine compounds remained nonaggregated in tetrahydrofuran at the studied concentration ranges. Metallophthalocyanines ( 4 { 7 ) were tested for their antioxidant activities. The antioxidant activity processes included evaluation of radical-scavenging activity, chelat- ing activity, and reducing power. These compounds were compared to standard antioxidant ascorbic acid. The electronic data of the new compounds were obtained by computational calculations at the B3LYP/6-31G (d,p) level of theory.
Synthesis and Characterization of Bionanomaterials and Evaluation of Their Antioxidant, Antibacterial, and DNA Cleavage Activities
(Chemistry Select, 2021) Tarhan, Tuba; Dündar, Abdurrahman; Okumuş, Veysi; Çulha, Mustafa
In this study, the hexagonal boron nitride (hBN) (1), poly-levodopa (P-L(DP) (2), P-L(DP) coated hBN (hBN@P(L-DP)) (3), and silver nanoparticles (AgNPs) decorated hBN@P(L-DP) (hBN@P(L-DP)-AgNPs) (4) were synthesized and characterized by multiple spectroscopic techniques. Additionally, their biological properties such as antioxidant, antibacterial, and DNA cleavage activities were determined. It is worth noting that, products 3 and 4 were newly synthesized structures. The antioxidant activities of all the nanomaterials 1, 2, 3, and 4 nanomaterials were investigated using some tests such as DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging and reducing power ability. Among the synthesized nanomaterials, product 2 exhibited the highest radical scavenging (64.8±1.94 %) and reducing power activity (0.61±0.017) at a concentration of 200 mg L−1. Product 4 was determined to have antibacterial activity against all three Gram-positive and three Gram-negative test bacteria. In addition, all the nanomaterials were tested for cleavage activity using pBR 322 plasmid DNA, as a result of which it was determined that only product 4 showed the ability of cleavage from both chains of DNA.

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