Tıbbi Hizmetler ve Teknikler Bölümü Koleksiyonu

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

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Citation - WoS: 11
Citation - Scopus: 12
Preconcentrations of Pb(II), Ni(II) and Zn(II) by solid phase bio-extractor using thermophilic Bacillus subtilis loaded multiwalled carbon nanotube biosorbent
(ScienceDirect, 2023) Ozdemir, Sadin; Dündar, Abdurrahman; Dizge, Nadir; Kılınç, Ersin; Balakrishnan, Deepanraj; Prasad, Kashi Sai; Senthilkumar, Natarajan
An alternative biotechnological solid phase bio-extraction (SPE) method was developed. Bacillus subtilis loaded multiwalled carbon nanotube was designed and used as biosorbent for the preconcentrations of Pb(II), Ni(II), and Zn(II). The experimental parameters such as sample flow rate, pH of sample solution, amounts of Bacillus subtilis and multiwalled carbon nanotube, volume of sample solution and reusability of column which affects the analytical characteristics of the SPE method were investigated in details. Surface structures were investigated by using FTIR, SEM. The best pH was determined as 5.0 and the percentages recoveries of Zn(II), Ni(II), and Pb(II) were determined as 99.1%, 98.7%, and 96.2%, respectively, at a flow rate of 3 mL/min. In this study, in which the profitable sample volume was determined as 400 mL and the amount of multiwalled carbon nanotube (MWCNT) as 50 mg. It was also observed that the column had a significant potential to preconcentrate Zn(II), Ni(II), and Pb(II) even after 25 reuses. The biosorption capacities for Pb(II), Ni(II) and Zn(II) were calculated as 34.2 mg/g, 36.8 mg/g and 45.5 mg/g respectively. The LOD values were calculated as 0.024 ng/mL for Pb(II), 0.029 ng/mL for Ni(II), and 0.019 ng/mL for Zn(II). The linear range was detected as 0.25–25 ng/mL. The concentrations of Pb(II), Ni(II), and Zn(II) in a variety of real food samples were determined by using developed method after application of certified reference sample.
Citation - WoS: 4
Citation - Scopus: 4
Application of Half-Sandwich Metal-Phosphinite Compounds to Biological Activities: Determine the energies of the HOMO and LUMO levels
(Wiley Online Library, 2022) Meriç, Nermin; Rafikova, Khadichakhan; Zazybin, Alexey; Güzel, Remziye; Kayan, Cezmi; Karakaş, Duygu Elma; Dündar, Abdurrahman; ISLAM, Sholpan; Okumuş, Veysi; Aydemir, Murat
Mononuclear transition metal complexes 1-(furan-2-yl)ethyldiphenyl[dichloro(η6-p-cymene)ruthenium(II)]phosphinite, (2), 1-(furan-2-yl)ethyldiphenyl[dichloro(η6-benzene) ruthenium(II)] phosphinite (3), 1-(furan-2-yl)ethyldipheny[chloro(η4-1,5-cyclooctadiene)rhodium(I)]phosphinite (4), 1-(furan-2-yl)ethyldiphenyl[dichloro (η5pentamethylcyclopentadienyl)iridium (III)] phosphinite (5) were synthesized and characterized by microanalysis, infrared, MS, and NMR spectroscopy. The biological activities of the complexes were also tested. Compounds 2 and 5 were the best complexes at DPPH radical scavenging and reducing power activity at 73.27 % and 0.41 at 200 μg/mL, respectively. The highest antimicrobial activity exhibited by complex 3 as 14 mm inhibition zone against S. aureus. All of the complexes have cleaved the DNA from the double-strand and exhibited three bands on gel electrophoresis. Moreover, cyclic voltammetry studies of the phosphinite complexes were carried out to determine the energies of the HOMO and LUMO levels as well as to estimate their electrochemical and some electronic properties.
Citation - WoS: 12
Citation - Scopus: 14
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.
Citation - WoS: 65
Citation - Scopus: 70
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.
Citation - WoS: 25
Citation - Scopus: 29
Economic fast synthesis of olive leaf extract and silver nanoparticles and biomedical applications
(Taylor & Francis Online, 2021) Atalar, Mehmet Nuri; Baran, Ayşe; Baran, Mehmet Fırat; Keskin, Cumali; 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.
Citation - WoS: 12
Citation - Scopus: 12
Role of 2.4 Ghz Radiofrequency Radiation Emitted From Wi-Fi on Some Mirna and Faty Acids Composition in Brain
(Taylor & Francis inc, 2022) Dasdag, Suleyman; Akdag, Mehmet Zulkuf; Bashan, Mehmet; Kizmaz, Veysi; Erdal, Nurten; Erdal, Mehmet Emin; Yegin, Korkut
The purpose of this study is to investigate the effects of 2.4 GHz Wi-Fi exposure, which is continuously used in the internet connection by mobile phones, computers and other wireless equipment, on microRNA and membrane and depot fatty acid composition of brain cells. Sixteen Wistar Albino rats were divided equally into two groups such as sham and exposure. The rats in the experimental group (n = 8) were exposed to 2.4 GHz RFR emitted from a Wi-Fi generator for 24 h/day for one year. The animals in the control group (n = 8) were kept under the same conditions as the experimental group, but the Wi-Fi generator was turned off. At the end of the study, rats were sacrificed and brains were removed to analyze miRNA expression and membrane and depot fatty acids of brain cells. We analyzed the situation of ten different miRNA expressions and nineteen fatty acid patterns in this study. We observed that long-term and excessive exposure of 2.4 GHz Wi-Fi radiation increased rno-miR-181a-5p, phosphatidylserine (PS) and triacylglycerol (TAG) in the brain. In conclusion, 2.4 GHz Wi-Fi exposure has the potential to alter rno-miR-181a-5p expression and the fatty acid percentage of some membrane lipids such as phospholipid (PL), phosphatidylserine (PS) and triacylglycerol (TAG), which are depot fats in the brain. However, the uncontrolled use of RFRs, whose use and diversity have reached incredible levels with each passing day and which are increasing in the future, may be paving the way for many diseases that we cannot connect with today.
Investigation of toxin genes in Staphylococcus aureus strains isolated in Mustafa Kemal University Hospital
(2011) Demir Cemil; Aslantas, Ozkan; Duran, Nızamı; Ocak, S; Özer, Burcın
Aim: The aim of this study was to investigate the presence of genes encoding staphylococcal enterotoxins (SEs), exfoliative toxins (ETAs, ETBs), and toxic shock syndrome toxin-1 (TSST-1) by polymerase chain reaction (PCR) in Staphylococcus aureus strains isolated from various clinical samples from the Mustafa Kemal University Hospital. In addition, PCR-based restriction fragment length polymorphism (RFLP) analysis of the coa gene was employed to genotype the isolates. Materials and methods: A total of 120 S. aureus strains isolated from various clinical samples (blood, wounds, urine, conjuctival swabs, and tracheal aspirate) over a 1 year period, 2007-2008, were used in this study. Results: Almost 65.8% of the isolates possessed at least one toxin gene. The genes most frequently found were seg-sei (40.8%), followed by sea (30%) and eta (19.2%). Overall, 35 toxin genotypes were observed, among which the genotypes seg-sei, sea-seg-sei, and sea-see predominated at the rate of 8.3%, 5.8%, and 5%, respectively. Four coagulase genotype patterns were observed, with molecular sizes ranging from 570 to 970 bp. Coo-based RFLP analysis revealed 7 different patterns using Conclusion: Our results have revealed that toxin genes were very prevalent among S. aureus isolates, and the toxigenic isolates were independent of the genotypes obtained by PCR-RFLP of the coa gene (P > 0.05).
Citation - WoS: 1
Citation - Scopus: 2
Synthesis and Biological Properties of Axially Bis(3,4,5-Trimethoxybenzyloxy) Phthalocyaninato Silicon (IV)
(Elsevier Science S.A., 2024) Solgun, Derya Gungordu; Ozdemir, Sadin; Dundar, Abdurrahman; Agirtas, Mehmet Salih
In this study, bis(3,4,5-trimethoxybenzyloxy) phthalocyaninato silicon (IV) was obtained from the reaction of 3,4,5-trimethoxybenzyl alcohol with SiPcCl 2 . This phthalocyanine was characterized using 1 H NMR, FTIR, UV - vis and mass spectra. 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, antidiabetic, deoxyribonucleic acid (DNA) cutting, biofilm inhibition, anti -microbial and antimicrobial photodynamic therapy (aPDT) activities of newly synthesized bis(3,4,5-trimethoxybenzyloxy) phthalocyaninato silicon (IV) molecule were studied. The best activities were 41.58 % at 100 mg/L for antioxidant and 41.66 % for antidiabetic at 400 mg/L concentration. The molecule degraded the biofilm matrix formed by Pseudomonas aeruginosa and Staphylococcus aureus as 78.61 % and 89.26 %, at 50 mg/L concentration, respectively. It was observed that E. coli , which was used as a model microorganism, was inhibited at a level close to 100 % even at the lowest concentration of 50 mg/L. While double strand break was observed at 50 mg/L DNA cutting activity, it was determined that DNA was reduced to nucleotides at 100 and 200 mg/L. The Pc also displayed effective antimicrobial and aPDT abilities against pathogens. With the application of aPDT, the effectiveness of antimicrobial activity increased 2 to 4 times. These increase rates are very important. The main conclusion of the study was that the newly synthesized compound exhibited various effective biological activities such as effective antioxidant, antidiabetic, DNA cleavage, antimicrobial, aPDT, biofilm inhibition and microbial cell viability inhibition.
Citation - WoS: 24
Citation - Scopus: 27
Efficacy of antimicrobial peptide LL-37 against biofilm forming Staphylococcus aureus strains obtained from chronic wound infections
(Elsevier, 2022) Demirci, Mehmet; Yigin, Akin; Demir, Cemil
The antimicrobial peptide LL-37 showed inhibitory effects against Staphylococcus aureus strains, which often responsible for wound infections. Understanding the molecular mechanisms of biofilm-containing wound infections is important. Thus, this study aimed to investigate both the antimicrobial and biofilm efficacy of LL-37 against biofilm-positive methicillin-susceptible S. aureus (MSSA) strains and biofilm-positive methicillin-resistant S. aureus (MRSA) strains obtained from chronic wound infections and its effect on different quorum sensing and virulence genes at suboptimal concentrations. Fifteen biofilm-forming MRSA and 15 biofilm-forming MSSA strains were included in this study. The minimum inhibitory concentration (MIC) values and biofilm formation were tested by microdilution methods. Real-time PCR was performed to determine gene expression levels. MIC values for LL-37 were 89.6 mg/L and 132.3 mg/L for MSSA and MRSA strains, respectively. No statistically significant difference was found between MRSA and MSSA strains in terms of the effect of LL-37 on biofilm formation. A statistically significant difference was found between MRSA and MSSA strains for atlA, RNAIII, and agrA gene expression levels following exposure to a suboptimal concentration of LL-37. Ultimately, the required LL-37 antimicrobial concentration was quite high; however, LL-37 antibiofilm concentration may be acceptable for use in humans against biofilm-forming MRSA and MSSA strains. This is the first study to investigate to effect of a suboptimal LL-37 concentration on gene expression levels of biofilm-forming MSSA and MRSA strains. LL-37 affected quorum sensing and biofilm producing mechanisms, even at suboptimal MIC concentrations.
Citation - WoS: 20
Citation - Scopus: 24
Kinetic and isotherm investigation into the removal of heavy metals using a fungal-extract-based bio-nanosorbent
(Environmental Technology and Innovation, 2020) Yıldırım, Ayfer; Baran, Mehmet Fırat; Acay, Hilal
Adsorption is very economical and environmentally friendly method that is commonly accepted as a promising technique for the removal of heavy metals. In this study a fungal-extract-based (FE-CB) bio-nanosorbent was prepared and used as an efficient biosorbent for the removal of heavy metals, namely Cu(II) and Ni(II), from aqueous solutions. FE-CB was characterized by scanning electron microscope, Brunauer–Emmett–Teller surface area and porosity analyzer, Fourier transform infrared, x-ray diffraction, differential scanning calorimeter, thermalgravimetric analysis and zeta potential. The Brunauer–Emmett–Teller surface area, pore volume and average pore diameter of FE-CB were 7.43 m2/g, 0.060 cm3/g, and 2.82 nm, respectively. The adsorbtion properties of FE-CB onto both Cu(II) and Ni(II) were investigated in terms of biosorbent dosage, temperature, initial concentration of Cu(II) and Ni(II) ions, pH and contact time in the batch experiments. The dependence of the biosorption mechanism on pH was revealed and the optimum pH was determined as 6 for Ni(II) and 5 for Cu(II). The Langmuir and Freundlich isothermal models and the kinetic Pseudo-first-order and Pseudo-second-order kinetic models were used to describe the adsorption performance of FE-CB. The activation energy was calculated by pseudo-second-order rate constants. In addition, thermodynamic parameters, standard Gibbs free energy, standard enthalpy and standard entropy were analyzed using the (Van't Hoff equation). The biosorption process was found to be spontaneous, favorable and endothermic.
Citation - WoS: 44
Citation - Scopus: 52
Magnetic solid phase extractions of Co(II) and Hg(II) by using magnetized C-micaceus from water and food samples
(ELSEVIER SCI LTD, 2019) Ozdemir, Sadin; Mohamedsaid, Siham Abdullah; Kilinc, Ersin; Soylak, Mustafa
A new bio-MSPE sorbent based on the use of C. micaceus and gamma-Fe2O3 magnetic nanoparticle was prepared for the preconcentrations of Co(II) and Hg(II). Critical parameters including pH, flow rate, quantity of C. micaceus, quantity of gamma-Fe2O3 magnetic nanoparticle, eluent (type, concentration and volume), sample volume, and foreign ions were examined. Surface structure and variations after interaction with Co(II) and Hg(II) of bio-MSPE sorbent were investigated by FT-IR, SEM, and EDX. The impact of bio-MSPE column reusage was also tested. The biosorption capacities were determined as 24.7 mg g(-1) and 26.2 mg g(-1), respectively for Co(II) and Hg(II). Certified reference materials were utilized to find out the accuracy of the prepared bio-MSPE method. This novel bio-MSPE method was accomplished by being applied to real food and water samples. In particular, it will be possible to make use of C. micaceus as new alternatives, in environmental biotechnology applications.
Citation - WoS: 35
Citation - Scopus: 39
Highly improved solar cell efficiency of Mn-doped amine groups-functionalized magnetic Fe3O4@SiO2 nanomaterial
(Wiley Online Library, 2021) Kutluay, Sinan; Horoz, Sabit; Şahin, Ömer; Ekinci, Arzu
Herein, magnetic Fe3O4@SiO2 nanomaterial functionalized with amine groups (Fe3O4@SiO2@IPA) doped with manganese (Mn) was prepared, characterized and used for solar cell application. Fe3O4@SiO2@IPA-Mn was prepared via the co-precipitation and sol-gel techniques. Energy-dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) measurements were performed to examine the structure of Fe3O4, Fe3O4@SiO2, Fe3O4@SiO2@IPA and Fe3O4@SiO2@IPA-Mn. General morphology and textural properties of the prepared magnetic nanomaterials were clarified by Brunauer-Emmett-Teller (BET) and scanning electron microscopy (SEM). In addition, Ultraviolet-visible (UV-Vis) spectroscopy and thermal gravimetric analysis (TGA) were used to have a knowledge about the energy band gap and thermal behavior of the prepared magnetic nanomaterials. The energy band gap of Fe3O4@SiO2@IPA with spinel structure was determined as approximately 2.48 eV. It was understood that Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@IPA showed type IV-H3 hysteresis cycle according to IUPAC. From the BET data, it was determined that the specific surface areas of Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@IPA were 60.85, 28.99 and 40.41 m(2)/g, respectively. The pore size distributions of Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@IPA were calculated as 8.55, 1.53 and 1.70 nm, respectively, by the BJH method. Also, it was observed that the dominant pore widths of Fe3O4, Fe3O4@SiO2 and Fe3O4@SiO2@IPA were calculated similar to 5.58, similar to 0.88 and similar to 17.92 nm, respectively, by the DFT method. Au/CuO/Fe3O4@SiO2@IPA-Mn/ZnO/SnO2: F solar cell device was created using existing Fe3O4@SiO2@IPA-Mn as a buffer layer. The power conversion efficiency (%) of Fe3O4@SiO2@IPA-Mn based solar cell device was calculated as 2.054. This finding suggest that Fe3O4@SiO2@IPA-Mn can be used as a promising sensitizer in solar cell technology. Moreover, in this study, the effectiveness of the modification of manganese (one of the transition metals, which is cheap and easily available) with magnetic nanomaterials in the use of solar cell technology was demonstrated for the first time.
Citation - WoS: 34
Citation - Scopus: 38
Fabrication and characterization of 3,4-diaminobenzophenone-functionalized magnetic nanoadsorbent with enhanced VOC adsorption and desorption capacity
(Environmental Science and Pollution Research, 2021) Ece, Mehmet Şakir; Şahin, Ömer; Kutluay, Sinan; Horoz, Sabit
The present study, for the first time, utilized 3,4-diaminobenzophenone (DABP)-functionalized Fe3O4/AC@SiO2 (Fe3O4/AC@SiO2@DABP) magnetic nanoparticles (MNPs) synthesized as a nanoadsorbent for enhancing adsorption and desorption capacity of gaseous benzene and toluene as volatile organic compounds (VOCs). The Fe3O4/AC@SiO2@DABP MNPs used in adsorption and desorption of benzene and toluene were synthesized by the co-precipitation and sol-gel methods. The synthesized MNPs were characterized by SEM, FTIR, TGA/DTA, and BET surface area analysis. Moreover, the optimization of the process parameters, namely contact time, initial VOC concentration, and temperature, was performed by applying response surface methodology (RSM). Adsorption results demonstrated that the Fe3O4/AC@SiO2@DABP MNPs had excellent adsorption capacity. The maximum adsorption capacities for benzene and toluene were found as 530.99 and 666.00 mg/g, respectively, under optimum process parameters (contact time 55.47 min, initial benzene concentration 17.57 ppm, and temperature 29.09 °C; and contact time 57.54 min, initial toluene concentration 17.83 ppm, and temperature 27.93 °C for benzene and toluene, respectively). In addition to the distinctive adsorptive behavior, the Fe3O4/AC@SiO2@DABP MNPs exhibited a high reproducibility adsorption and desorption capacity. After the fifth adsorption and desorption cycles, the Fe3O4/AC@SiO2@DABP MNPs retained 94.4% and 95.4% of its initial adsorption capacity for benzene and toluene, respectively. Kinetic and isotherm findings suggested that the adsorption mechanisms of benzene and toluene on the Fe3O4/AC@SiO2@DABP MNPs were physical processes. The results indicated that the successfully synthesized Fe3O4/AC@SiO2@DABP MNPs can be applied as an attractive, highly effective, reusable, and cost-effective adsorbent for the adsorption of VOC pollutants. Graphical abstract[Figure not available: see fulltext.]
Citation - WoS: 57
Citation - Scopus: 61
Investigation of the antibiotic resistance and biofilm-forming ability of Staphylococcus aureus from subclinical bovine mastitis cases
(ELSEVIER SCIENCE INC, 2016) Aslantas, Ozkan; Demir, Cemil
A total of 112 Staphylococcus aureus isolates obtained from subclinical bovine mastitis cases were examined for antibiotic susceptibility and biofilm-forming ability as well as genes responsible for antibiotic resistance, biofilm-forming ability, and adhesin. Antimicrobial susceptibility of the isolates were determined by disk diffusion method. Biofilm forming ability of the isolates were investigated by Congo red agar method, standard tube method, and microplate method. The genes responsible for antibiotic resistance, biofilm-forming ability, and adhesion were examined by PCR. Five isolates (4.5%) were identified as methicillin-resistant Staph. aureus by antibiotic susceptibility testing and confirmed by mecA detection. The resistance rates to penicillin, ampicillin, tetracycline, erythromycin, trimethoprim-sulfamethoxazole, enrofloxacin, and amoxicillin-clavulanic acid were 45.5, 39.3, 33, 26.8, 5.4, 0.9, and 0.9%, respectively. All isolates were susceptible against vancomycin and gentamicin. The blaZ (100%), tetK (67.6%), and ermA (70%) genes were the most common antibiotic-resistance genes. Using Congo red agar, microplate, and standard tube methods, 70.5, 67, and 62.5% of the isolates were found to be biofilm producers, respectively. The percentage rate of icaA, icaD, and bap genes in Staph. aureus isolates were 86.6, 86.6, and 13.4%, respectively. The adhesion molecules fnbA, can, and clfA were detected in 87 (77.7%), 98 (87.5%), and 75 (70%) isolates, respectively. The results indicated that Staph. aureus from sublinical bovine mastitis cases were mainly resistant to beta-lactams and, to a lesser extent, to tetracycline and erythromycin. Also, biofilm- and adhesion-related genes, which are increasingly accepted as an important virulence factor in the pathogenesis of Staph. aureus infections, were detected at a high rate.
Citation - WoS: 9
Citation - Scopus: 9
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.
Citation - WoS: 29
Citation - Scopus: 31
Structural analysis and biological functionalities of iron(III)- and manganese(III)-thiosemicarbazone complexes: in vitro anti-proliferative activity on human cancer cells, DNA binding and cleavage studies
(SPRINGER, 2019) Kaya, Busra; Yilmaz, Zehra Kubra; Sahin, Onur; Aslim, Belma; Tukenmez, Ummugulsum; Ulkusever, Bahri
One iron(III) and two manganese(III) complexes based on thiosemicarbazone were synthesized and characterized using analytical and spectroscopic data. The crystallographic analysis showed the square pyramid structures of the complexes. Electronic spectra analysis was performed to determine the nature of the interaction between the complexes and calf thymus DNA (CT-DNA). DNA cleavage activities of the complexes were examined by gel electrophoresis (pBR322 DNA). The cytotoxicity of the complexes was determined against human cervical carcinoma (HeLa) and human colorectal adenocarcinoma (HT-29) cell lines by MTT assay. The results indicated that complex Fe1 is bound to CT-DNA via the intercalation mode, while complexes Mn1 and Mn2 are bound to CT-DNA via groove binding and/or electrostatic interactions rather than the intercalation mode. In addition, they showed good binding activity, which followed the order of Fe1>Mn2>Mn1. Complexes were found to promote the cleavage of DNA from supercoiled form (SC, Form I) to nicked circular form (NC, Form II) without concurrent formation of Form III, revealing the single-strand DNA cleavage. No significant cleavage was found in the presence of Mn1 and Mn2; however, it was observed at 2000 and 3000 mu M concentrations of Fe1. The ability of Fe1 to cleave DNA was greater than that of other complexes and these results are in conformity with their DNA-binding affinities. Cytotoxicity determination tests revealed that the complex Fe1 on HeLa and HT-29 cells exhibited a higher anti-proliferative effect than Mn1 and Mn2 (Fe1>Mn2>Mn1). These studies suggested that the complex Fe1 could be a good candidate as a chemotherapeutic drug targeting DNA. [GRAPHICS]
Citation - WoS: 46
Citation - Scopus: 53
Development of Novel Fe3O4/AC@SiO2@1,4-DAAQ Magnetic Nanoparticles with Outstanding VOC Removal Capacity: Characterization, Optimization, Reusability, Kinetics, and Equilibrium Studies
(Industrial and Engineering Chemistry Research, 2021) Ece, Mehmet Şakir; Kutluay, Sinan; Şahin, Ömer; Horoz, Sabit
The adsorption of pollutants to the surface of adsorbents plays a critical role in the effectiveness of adsorption technology for air purification applications. Herein, novel magnetic nanoparticles functionalized with 1,4-diaminoanthraquinone (1,4-DAAQ), namely, Fe3O4/activated carbon (AC)@SiO2@1,4-DAAQ, were innovatively synthesized via co-precipitation and sol-gel techniques. After that, these nanoparticles were used for high-efficiency removal of volatile organic compounds (VOCs) (i.e., benzene and toluene). The synthesized nanoparticles were characterized by various techniques such as Fourier transform IR spectroscopy, thermogravimetric analysis/differential thermal analysis, scanning electron microscopy, and Brunauer-Emmett-Teller analysis. The dynamic adsorption process of VOCs was optimized based on operating parameters. The adsorption experiments revealed that Fe3O4/AC@SiO2@1,4-DAAQ showed exceptional performance for the removal of VOCs. It was observed that for benzene, Fe3O4, AC, Fe3O4/AC, Fe3O4/AC@SiO2, and Fe3O4/AC@SiO2@1,4-DAAQ exhibited dynamic adsorption capacities of 180.25, 228.87, 295.84, 382.10, and 1232.77 mg/g, respectively. Additionally, for toluene, they exhibited dynamic adsorption capacities of 191.08, 274.53, 310.26, 421.30, and 1352.16 mg/g, respectively. This indicated that the modification of 1,4-DAAQ could greatly enhance the dynamic adsorption capacity of Fe3O4/AC@SiO2@1,4-DAAQ for VOCs. In addition to the apparent adsorptive behavior in removing VOCs, Fe3O4/AC@SiO2@1,4-DAAQ exhibited high repeatability. After ten consecutive adsorption/desorption cycles, for benzene and toluene, Fe3O4/AC@SiO2@1,4-DAAQ retained 79.36 and 78.24% of its initial adsorption capacity, respectively. According to the characterization results, the average pore diameter for Fe3O4/AC@SiO2@1,4-DAAQ was determined to be 24.46 nm, indicating that they were in the mesopore range. The adsorption mechanism of the VOCs on Fe3O4/AC@SiO2@1,4-DAAQ was clarified by investigating the isotherm and kinetic criteria in detail. Isotherm models suggested that the adsorption process of VOCs is physical. Moreover, from the analysis of diffusion-based rate-limiting kinetic models, the findings reveal a combination of intraparticle diffusion as well as film diffusion throughout the adsorption process of VOCs. In addition, it was concluded from the analysis of the mass transfer model factors that global mass transfer and internal diffusion are more effective than film diffusion. The results demonstrated that the Fe3O4/AC@SiO2@1,4-DAAQ nanoadsorbent is a promising material for the effective removal of VOCs.
Competitive Biosorption of Azo-Dyes in Aqueous Solution on Magnetic Biosorbent Nanoparticles
(2018) Tarhan, Tuba; Tural, Bilsen; Tural, Servet
Abstract— In this study, glutaraldehyde cross-linked magnetic chitosan nanoparticles (GMCNs) were prepared through crosslinking modification of magnetic chitosan nanoparticles (MCNs) using glutaraldehyde as crosslinker that exhibited excellent adsorption performance Reactive Black 5 (RB5) and Metanil Yellow (MY) in dyes mixture solution. The characterization of synthesized GMCNs was performed by fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM) analyses. Adsorption characteristics of dyes mixture solution on to GMCNs have been studied and results indicated that the adsorption capacities were affected by initial dye concentrations and contact time. The adsorption of dyes mixture solution experiments were well fitted the pseudo-second-order reaction. The technique used in this study offers a convenient and economical method for the preparation of nanoparticles, which can facilitate a higher adsorption capacity and thus more efficient adsorption of dyes in an aqueous solution compared with nature or other synthetic materials Keywords— Azo Dye, Biosorption, Biosorption isotherm, Biosorption kinetics, Magnetic Biosorbent
Citation - WoS: 22
Citation - Scopus: 24
Boletus edulis loaded with gamma-Fe2O3 nanoparticles as a magnetic sorbent for preconcentration of Co(II) and Sn(II) prior to their determination by ICP-OES
(SPRINGER WIEN, 2018) Özdemir, Sadin; Yalçın, M. Serkan; Kılınç, Ersin; Soylak, Mustafa
The authors show that the fungus Boletus edulis loaded with gamma-Fe2O3 nanoparticles is a viable sorbent for magnetic solid phase extraction of trace levels of Co(II) and Sn(II). The surface structure of immobilized magnetized B. edulis was characterized by FT-IR, SEM and EDX. Experimental parameters were optimized. Following elution with 1 M HCl, the ions were quantified by ICP-OES. The limits of detection are 21 pg.mL(-1) for Co(II), and 19 pg.mL(-1) for Sn(II). The preconcentration factors are 100 for both ions. The sorption capacities of the sorbent are 35.8 mg.g(-1) for Co(II) and 29.6 mg.g(-1) for Sn(II). The method was applied to the analysis of certificated reference materials and gave >= 95% recoveries with low RSDs. It was also successfully applied to the quantification of Co(II) and Sn(II) in spiked environmental and food samples.
Citation - WoS: 20
Citation - Scopus: 25
Thermophilic Geobacillus galactosidasius sp nov loaded gamma-Fe2O3 magnetic nanoparticle for the preconcentrations of Pb and Cd
(ELSEVIER SCI LTD, 2016) Ozdemir, Sadin; Kilinc, Ersin; Okumus, Veysi; Poli, Annarita; Nicolaus, Barbara; Romano, Ida
Thermophilic bacteria, Geobacillus galactosidasius sp nov. was loaded on gamma-Fe2O3 magnetic nanoparticle for the preconcentrations of Pb and Cd by solid phase extraction before ICP-OES. pH and flow rate of the solution, amounts of biosorbent and magnetic nanoparticle, volume of sample solution, effects of the possible interferic ions were investigated in details. Linear calibration curves were constructed in the concentration ranges of 1.0-60 ng mL (1) for Pb and Cd. The RSDs of the method were lower than 2.8% for Pb and 3.8% for Cd. Certified and standard reference samples of fortified water, wastewater, poplar leaves, and simulated fresh water were used to accurate the method. LOD values were found as 0.07 and 0.06 ng mL (1) respectively for Pb and Cd. The biosorption capacities were found as 34.3 mg g (1) for Pb and 37.1 mg g (1) for Cd. Pb and Cd concentrations in foods were determined. Surface microstructure was investigated by SEM-EDX. (C) 2015 Elsevier Ltd. All rights reserved.

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