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Öğe 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, MustafaThe 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.Öğe Investigations of Hg(II) and Pb(II) tolerance, removal and bioaccumulation and their effects on antioxidant enzymes on thermophilic Exiguobacterium profundum(Human and Ecological Risk Assessment, 2020) Kılınç, Ersin; Akkoyun, Mahire Bayramoğlu; Özdemir, SadinHg(II) and Pb(II) tolerance, removal, bioaccumulation and effects on antioxidant enzymes of thermophilic Exiguobacterium profundum were investigated. The results indicated that Hg(II) was more toxic than Pb(II) to E. profundum. E. profundum was also more tolerant in solid medium than in liquid medium for Pb(II) and Hg(II). The bacterial growth was not significantly influenced at 1.0 and 2.5 mg/L Pb(II) and Hg(II) for 24 h. The highest Hg(II) and Pb(II) bioaccumulation amounts were determined as 37.56 and 54.35 mg metal/dried bacteria, respectively. Bioaccumulation capacities of the cell membrane of E. profundum for Hg(II) and Pb(II) were determined. The different concentrations of Pb(II) and Hg(II) enhanced the SOD and CAT enzymes. In addition, variations of the surface macrostructure and the functionality of E. profundum after the interaction with Hg(II) and Pb(II) were investigated by the scanning electron microscope (SEM) and the Fourier transform infrared spectroscopy (FT-IR), respectively. This investigation obviously showed that thermophilic E. profundum can also be applied for removal and recovery of toxic metals from industrial wastewater. Clearly, a further investigation should be utilized by thermophilic microorganisms. According to antioxidant enyzme activities, E. profundum can be also used as a bioindicator for the detection of toxic metal pollution in natural water samples.Öğe Several biological properties and synthesis of 2-(4-methylthiazol-5-yl) ethoxy substitute zinc phthalocyanine(John Wiley and Sons Ltd, 2023) Güngördü Solgun, Derya; Özdemir, Sadin; Dündar, Abdurrahman; Ağırtaş, Mehmet SalihIn this study, 4-(2-(4-methylthiazol-5-yl) ethoxy) phthalonitrile (3) and zinc phthalocyanine complex (4) were synthesized and characterized. UV–vis and fluorescence spectra, aggregation, and fluorescence parameters of the zinc phthalocyanine compound were investigated. As biological properties, DPPH radical capture, antidiabetic, DNA cutting, antimicrobial, photodynamic antimicrobial, anti-biofilm activities, and microbial cell viability parameters of the compounds were determined. The highest antioxidant activity was found as 62.80% at 100 mg/L concentration with compound 4, and compound 4 also showed the best antidiabetic activity as 65.17% at 400 mg/L concentration. In DNA cutting activity, it was determined that 3 and 4 cut DNA at all concentrations. For compounds 3–4, the minimum inhibitory concentration (MIC) values were found to be 32 and 16 mg/L for Enterococcus hirae and Enterococcus feacalis, respectively. The strongest MIC value of photodynamic antimicrobial activity was achieved as 4 mg/L for E. feacalis with 4. It was observed that both compounds inhibited the microbial viability activity of Escherichia coli by 100% at concentrations of 100 mg/L. Compound 4 inhibited biofilms of Pseudomonas aureginosa and Staphylococcus aureus as 92.48% and 98.56% at 50 mg/L concentration, respectively.Öğe Solid Phase Extraction Based on the Use of Agaricus arvensis as a Fungal Biomass for the Peconcentrations of Pb and Al Prior to Their Determination in Vegetables by ICP-OES(ATOMIC SPECTROSCOPY, 2013) Kilinc, E (Kilinc, Ersin); Dündar, Abdurrahman; Özdemir, Sadin; Okumuş, VeysiA solid phase extraction (SPE) method based on the use of a fungal biomass as sorbent was developed for the preconcentrations of Pb and Al. Agaricus arvensis was immobilized on Amberlite XAD-4 and loaded onto a column. Important parameters such as pH and flow rate of the solution, amount of biosorbent and resin, volume of sample solution, which affect the efficiency of the preconcentration procedure for Pb and Al, were optimized. The effect of possible interfering ions, i.e., Cd2+, Cu2+, Ni2+, Zn2+, Co2+, Na+, K+, Ca2+, Mg2+, and Fe2+, was investigated. Experiments on the repeatability of the solid phase column showed that the same column could be used at least 30 cycles without loss of the biosorption efficiency for the recovery of Pb and Al. The limit of detection (LOD) of Pb and Al was found to be 0.10 ng m(L-1) and 0.03 ng mL(-1), respectively. The sensitivity of ICP-OES improved 39.8-fold for Pb and 39.5-fold for Al. Linearity was obtained in the concentration range of 1.25-50.0 ng mL(-1) for Pb and 0.5-50.0 ng mL(-1) for Al. The relative standard deviation (RSD) of the method under optimum conditions was lower than 8.4% (n=5) for Pb and Al, which was validated through the analysis of certified reference tea and poplar leaves samples. The biosorption capacity of immobilized Agaricus arvensis for Pb and Al was found to be 31.2 mg g(-1) and 45.7 mg g(-1), respectively. The developed method was applied to determine the concentrations of Pb and Al in various edible vegetable samples (cucumber, okra, tomato, beans, aubergine, watermelon, zucchini, pepper, melon, lettuce, roka, purslane, scallion, cress, parsley, cabbage, sugar cane, and basil) grown along the cultivated banks of the Tigris River in Diyarbakir, Turkey.Öğe Synthesis and antioxidant, aggregation, and electronic properties of 6-tert-butyl-1,4-benzodioxine substituted phthalocyanines(Turkish Journal of Chemistry, 2018) Ağırtaş, Mehmet Salih; Cabir, Beyza; Gümüş, Selçuk; Özdemir, Sadin; Dündar, AbdurrahmanAs 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.Öğe Synthesis and biological properties of axially bis − (3,4,5-trimethoxybenzyloxy) phthalocyaninato silicon (IV)(Elsevier, 2024) Güngördü Solgun, Derya; Özdemir, Sadin; Dündar, Abdurahman; Ağırtaş, Mehmet SalihIn this study, bis − (3,4,5-trimethoxybenzyloxy) phthalocyaninato silicon (IV) was obtained from the reaction of 3,4,5-trimethoxybenzyl alcohol with SiPcCl2. This phthalocyanine was characterized using 1H 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.Öğe Synthesis, characterization, aggregation behavior, antioxidant activity, and antibacterial activity of metallophthalocyanines carrying four phthalonitriles group(Editions de l'Academie Republique Populaire, 2016) Güven, M. Emin; Ağırtaş, M. Salih; Özdemir, Sadin; Dündar, AbdurrahmanA novel phthalonitrile derivative and zinc (II), cobalt (II), and cupper (II) phthalocyanines complexes were synthesis and characterized. The novel compounds have been characterized by using various spectroscopic data FTIR, UV/vis, NMR, elemental analysis etc. The aggregation investigations carried out in different concentrations indicate that 4- (4-(1-(4- phenoxyphenyl)-1-phenylethyl)phenoxy)phthalonitrile substituted phthalocyanine compounds do not have any aggregation behavior for the concentration range of 10-4-10-5 M in tetrahydrofuran. The antioxidant properties of the phthalonitrile and its phthalocyanine compounds were evaluated in three series of in vitro tests: DPPH free radical scavenging, ferrous ion chelating activity and reducing power. Antimicrobial activities of compounds were investigated.
