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© 2023 Elsevier LtdDue to increasing industrialization and overpopulation, the amount of toxic metals is increasing in the environment, including air, soil, water, and food. Solid phase extraction is an efficient and ideal technique to preconcentrate the toxic metals before their measurements by analytical instruments. Russula brevipes was immobilized on γ-Fe2O3 magnetic nanoparticles and employed as a SPE sorbent to preconcentrate the trace level of Pb(II), Mn(II), and Co(II). To investigate the extraction conditions, significant experimental parameters were examined in details. LODs were calculated as 0.022, 0.015, and 0.024 ng mL−1 for Pb(II), Mn(II), and Co(II), respectively. The biosorption capacities of R. brevipes immobilized γ-Fe2O3 were calculated as 43.1 mg g−1 for Pb(II), 54.9 mg g−1 for Mn(II), and 49.7 mg g−1 for Co(II). Pb(II), Mn(II), and Co(II) in food samples at trace levels were preconcentrated by applying the developed method.

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.

© 2021, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.In this work, the separations and preconcentrations of Zn(II) and Hg(II) ions on Bacillus lichenifoemis loaded onto Amberlite XAD-4 resin by solid-phase extraction has been performed. The biosorbent was characterized by using FT-IR, SEM, and EDX. pH, sample flow rate, eluent type and concentration, amount of B. licheniformis and XAD-4 resin, sample volume, and possible interfering ions effect were investigated in details as experimental variables in the SPE procedure. Limit of detection values for Zn(II) and Hg(II) were detected as 0.03 and 0.06 ng mL−1, respectively. 0.2–15 ng mL−1 linear range values were achieved for Zn(II) and Hg(II), respectively. Relative standard deviation values were found to be lower than 5%. For validation of the procedure, the certified standard reference materials (CWW-TM-D, EU-L-2, NCS ZC73O14, NCS ZC73350) were analyzed. The concentrations of Zn(II) and Hg(II) in water and food samples were measured by ICP-OES. Consequently, it can be inferred that the immobilized B. licheniformis microcolumn has ideal selectivity for Zn(II) and Hg(II) biosorption. Graphical abstract: [Figure not available: see fulltext.].

This work is focused on the synthesis of leucyl-glycine-functionalized γ-Fe2O3 magnetic nanoparticles coated by polydioxanone (γ-Fe2O3-CA-Leu-Gly-PDX) as a polyethersulphone (PES) membrane for biotechnological applications. The physicochemical characteristics were investigated by FT-IR, SEM, XRD, a vibrating sample magnetometer (VSM), and ICP-OES. The present investigation also centered on the several biological activities of γ-Fe2O3-CA-Leu-Gly-PDX. The 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and metal chelating activity was studied for evaluation of its antioxidant activity potential. It exhibited 100% DPPH radical scavenging and 93.33% metal chelating activity. With applicability to antimicrobial photodynamic therapy, DNA cleavage and antimicrobial activity, the cell viability of γ-Fe2O3-CA-Leu-Gly-PDX was investigated in detail. The γ-Fe2O3-CA-Leu-Gly-PDX demonstrated the significant biofilm inhibition activity as being 81.54% and 86.34% for P. aeruginosa and S. aureus, respectively. Moreover, a novel polyethersulphone nanocomposite membrane incorporated with γ-Fe2O3-CA-Leu-Gly-PDX was prepared. The performance of the γ-Fe2O3-CA-Leu-Gly-PDX-blended polyethersulphone (PES) membrane was investigated by measuring the antifouling and E. coli rejection. The nanocomposite membranes demonstrated remarkable antifouling properties in contrast with the pristine PES when BSA (bovine serum albumin) and E. coli were filtrated. A complete rejection was obtained by the composite membrane. After an application of the membrane study, the modified polyethersulphone (PES) membrane blended with γ-Fe2O3-CA-Leu-Gly-PDX removed 100% of the E. coli.

A solid-phase extraction method for separation-preconcentration of copper as 1-(2-pyridylazo)-2-naphthol (PAN) on Coprinus atramentaria has been presented. The copper concentration was determined by micro-sampling flame atomic absorption spectrometry (FAAS). It could be discussed that the developed method has low LOD in addition to high preconcentration factor. By considering the over advantages of recommended method, we can suggest the use of its to preconcentration of Cu(II) by routinly. The various analytical factors affecting the efficiency of extraction were optimised. Copper(II)-PAN chelate was quantitatively recovered at pH 6.0 on Coprinus atramentaria and eluted with 2 M HNO3. The limit of detection, limit of quantification, inter-day and intra-day precision values of copper were 0.7 mu g L-1, 2.33 mu g L-1, 5.31% and 5.15%, respectively. The pre-concentration factor was 70. The method was confirmed by applying the method to certified reference materials and addition-recovery tests prior to application to the determination of copper ions in various samples recovery results. The solid-phase extraction with FAAS is a successful method for the determination of copper in different samples.

WOS:000751882100006 PMID: 34695434 An ecofriendly preconcentration method was developed based on the use of Geobacillus galactosidasius sp. nov immobilized on Amberlite XAD-4 as an adsorbent for the preconcentrations of Hg and Sn. SEM-EDX performed for the investigation of surface functionality and morphology. The detailed investigations of factors such as pH of the solution, flow rate, interfering ions and sample volume have been thanks to the optimization of the preconcentration system. The optimum pHs were found as 5.0-7.0 for Hg and Sn and also the optimum flow rates were determined as 2 mL min(-1) for recovery of Hg and Sn. Under the best experimental conditions, limits of detections (LOD) were found as 0.53 ng mL(-1) for Hg and 0.27 ng mL(-1) for Sn. RSDs were calculated as 8.2% for Hg and 6.9% for Sn. The process was validated to use certified references (fish samples). ICP-OES was used to measure the levels of Hg and Sn in various real meal patterns after the devised technique was used. Concentrations of Hg and Sn were quantitively measured on gluten-free biscuit, flour, rice, Tuna fish, meat, chicken meat, potato, chocolate, coffee, tap water, energy drink and mineral water samples with low RSD. The developed method emerges as an innovative technology that will eliminate the low cost and toxic effect.

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. © 2021 Elsevier Inc.

This paper proposes the use of Anoxybacillus flavithermus SO-15 immobilized on iron oxide nanoparticles (NPs) as a novel magnetized biosorbent for the preconcentrations of uranium (U) and thorium (Th). The SPE procedure was based on biosorption of U(VI) and Th(IV) on a column of iron oxide NPs loaded with dead and dried thermophilic bacterial biomass prior to U(VI) and Th(IV) measurements by ICP-OES. The biosorbent characteristicswere explored using FT-IR, SEM, and EDX. Significant operational factors such as solution pH, volume and flow rate of the sample solution, amounts of dead bacteria and iron oxide nanoparticles, matrix interference effect, eluent type, and repeating use of the biosorbent on process yield were studied. The biosorption capacities were found as 62.7 and 56.4 mg g(-1) for U(VI) and Th(IV), respectively. The novel extraction process has been successfullyapplied to the tap, river, and lake water samples for preconcentrations of U(VI) and Th(IV).

We investigated the application of fungus Phallus impudicus loaded gamma-Fe2O3 nanoparticles as a biosorbent for magnetic solid phase extractions of trace levels of Zn(II) and Cr(III) ions from natural samples before their measurements by inductively coupled plasma optical emission spectrometry. The characterization of magnetized P. impudicus was performed using the scanning electron microscope, the energy dispersive X-ray and Fourier transform infrared spectroscopy. Important experimental factors were investigated. The experimental results fitted well to the Langmuir adsorption model and pseudo-second order kinetic model. Limit of detections of targeted ions by magnetic solid phase extraction method based on use of P. impudicus were found as 10.5 ngL(-1) and 12.6 ngL(-1) respectively for Cr(III) and Zn(II). The sorption capacities of the biosorbent were 22.8 mgg(-1) for Cr(III) and 25.6 mgg(-1) for Zn(II). The preconcentration factors were achieved as 100 for both of ions. RSDs for inter- and intraday precisions were found as lower than 2.0% and 2.1% respectively for both of targeted ions. The accuracy of the recommended process was tested by recovery measurements on the certificated reference materials and successfully applied for quantification recoveries of Cr(III) and Zn(II) ions from water and food samples.

The present study explores the biosorption potential of Pleurotus ostreatus immobilized magnetic iron oxide nanoparticles for solid-phase extractions of Ni(II) and Pb(II) ions from the water and food samples. It was characterized using FTIR, FE-SEM/EDX before and after analyte ions biosorption. Important operational parameters including the effect of initial pH, the flow rate of the sample solution and volume, amount of biomass and support material, interfering ions, best eluent, column reusability were studied. The biosorption capacities of fungus immobilized iron oxide nanoparticles were found as 28.6 and 32.1 mg g−1 for Ni(II) and Pb(II), respectively. The limit of detection (LOD) and limit of quantitation (LOQ) were achieved as 0.019 and 0.062 ng mL−1 for Ni(II), 0.041 and 0.14 ng mL−1 for Pb(II), respectively. The proposed method was validated by applying to certified reference materials and successfully applied for the preconcentrations of Ni(II) and Pb(II) ions from water and food samples by ICP-OES.

Pleurolus eryngii loaded Fe2O3 magnetic nanoparticles were developed as novel magnetic solid phase bio-extractors for the preconcentrations and extractions of Co(II) and Hg(II) from real samples. The metal binding surface groups of the prepared magnetic solid phase bio-extractors were investigated by FT-IR spectrometry, SEM and EDX. Several parameters influencing the magnetic extractions and preconcentrations of Co(II) and Hg (II) were examined and optimized, including pH, flow rate, quantity of P. eryngii, quantity of Fe2O3 magnetic nanoparticle, eluent type, concentration and volume, sample volume, and foreign ions. A good reusage (35 times) was obtained with the relative standard deviation (RSD) of < 5.0% for both magnetic solid phase bio-extractors. The biosorption capacities were determined for Co(II) and Hg(II) as 25.4 mg g(-1) and 30.3 mg g(-1), respectively, using P. eryngii loaded Fe2O3 magnetic nanoparticle column. The preconcentration factors for Co(II) and Hg(II) were found as 80 and 100, respectively, when using P. eryngii loaded Fe2O3 magnetic nanoparticle column. The developed procedures were validated through analysis of the certified reference materials and successfully utilized for the determinations of Co(II) and Hg(II) in real samples by inductively coupled plasma optical emission spectrometry (ICP-OES) with satisfactory results.

In the present study, we used E. profundum loaded onto Amberlite XAD-4 resin for solid-phase extraction (SPE) of Cu(II), Ni(II), and Pb(II). Some conditions of the SPE procedure, for instance, sample flow rate, pH, eluent type and concentration, the sample volume, amount of E. profundum XAD-4 resin, and the effects of foreign in-terferences ions are discussed in detail. Surface microstructures of the biosorbent were characterized by FTIR, FE-SEM/EDX before and after loading of metals. The biosorption capacities of E. profundum were determined as 49.83, 57.12, and 64.35 mg g(-1) for Pb(II), Cu(II), and Ni(II), respectively. The LOD values were calculated as 0.031 ng mL(-1), 0.042 ng mL(-1), and 0.043 ng mL(-1) for Cu(II), Ni(II), and Pb(II), respectively. The linear range was detected as 0.25-25 ng mL(-1). RSD values were lower than 5%. The concentrations of metal ions in water and food samples were measured by ICP-OES.

In this work, an alternative preconcentration process suggested based on using Tricholoma populinum as a fungal biosorbent for the sensitive preconcentration of Cu2+ and Co2+. Amberlite XAD-4 was utilized for the loading of the biomass in solid-phase extraction (SPE) procedure. It was found that T. populinum loaded with XAD-4 resin was a selective biosorbent for the preconcentration of Cu2+ and Co2+. Experimental variables in SPE procedure such as pH, the flow rate of the sample, type and concentration of eluent, amount of T. populinum and of XAD-4 resin, sample volume, and potential interfering ion effect were studied. Surface functionalities of the metal-loaded and metal-unloaded biosorbent were determined by comparing Fourier transform infrared spectroscopy spectra and scanning electron microscopy images. Limit of detection values for Cu2+ and Co2+ were found as 0.034 and 0.019 ng mL−1, respectively. The linear range was found as 0.2–15 ng mL−1 for both analytes. Relative standard deviation values were found as lower than 3.0%. Certified reference materials were applied for process validation, and also, the concentrations of Co2+ and Cu2+ were investigated in real water, vegetable, and soil samples. So, the method developed could be utilized for the preconcentrations of Cu2+ and Co2+ for routine analysis. This method can be used as an inexpensive and accessible alternative to GF-AAS or ICP-MS methods. © 2020, Islamic Azad University (IAU).

Hg(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., This academic work was linguistically supported by the Mersin Technology Transfer Office Academic Writing Center of Mersin University.

In this study, preconcentration and separation of Cu(II) and Pb(II) ions by using Fe3O4@SiO2@Bacillus pumilis before their determinations by flame atomic absorption spectrometry (FAAS) were investigated. The thermophilic Bacillus pumilis were isolated from Meyremderesi spring, Sirnak, Turkey. Effects of important parameters such as pH, adsorbent amount, eluent type, concentration and volume of eluent and sample volume on magnetic solid phase extraction (MSPE) were examined in details. The preconcentration factors for Cu(II) and Pb(II) ions were calculated as 30 and 40, respectively. The accuracy of the proposed extraction procedure was validated analysing certificated reference materials and addition - recovery tests. The concentration of copper and lead were determined in water samples from Turkey by Flame AAS after application developed preconcentration-separation method.

A new biosorbent, composed of Amberlite XAD-4 loaded with Anoxybacillus kestanboliensis, was developed and surface morphologies were investigated by SEM and FT-IR. It was used for solid phase column preconcentrations of Co(II) and Hg(II) before their measurements by ICP-OES. LODs were calculated as 0.04 and 0.06 ng mL−1 for Co(II) and Hg(II) respectively. The maximum biosorption capacities were determined as 24.3 and 27.8 mg g−1 for Co(II) and Hg(II) respectively. Preconcentration factors were achieved for Co(II) and Hg(II) as 80. The method validation was performed by analyzing certified reference materials. The new process was successfully utilized for the preconcentration of these metals in various food samples. It should be highlighted that the sensitivity of ICP-OES was critically improved by applying developed method. Hence, ICP-OES could be an effective alternative for ICP-MS and/or GF-AAS.

In this study, it was hypothesis that A. mongoliensis could be used as bioindicator for Ni (II) and Co (II). Thus, Ni (II) and Co (II) resistance, removal, bioaccumulation, and the impacts of them on antioxidant enzyme systems of thermophilic Anoxybacillus mongoliensis were investigated in details. The bioaccumulation of Ni (II) and Co (II) on the cell membrane of thermophilic A. mongoliensis, variations on surface macrostructure and functionality by FT-IR and SEM, and determination of antioxidant enzyme activities were also tested. The highest bioaccumulation values of Co (II) and Ni (II) were detected as 102.0 mg metal/g of dry bacteria at 10 mg/L for the 12th h and 90.4 mg metal/g of dry bacteria for the 24th h, respectively, and the highest Ni (II) and Co (II) cell membrane bioaccumulation capacities of A. mongoliensis were determined as 268.5 and 274.9 mg metal/g wet membrane, respectively at the 24th h. In addition, increasing on SOD and CAT activities were observed on depend of concentration of Ni (II) and Co (II) with respect to control. The antioxidant enzyme activity results also indicated that A. mongoliensis might be used as a bioindicator for Ni (II) and Co (II) pollution in environmental water specimens.

A magnetic solid-phase extraction (MSPE) method was developed for simultaneous preconcentrations of U(VI) and Th(IV) before their measurements by inductively coupled plasma optical emission spectrometry (ICP-OES). The main idea of this biotechnological application depends on the use of bacteria, thermophilic Bacillus cereus SO-14, as a solid-phase biosorbent. It was immobilized to gamma-Fe2O3 magnetic nanoparticles and used for MSPE. Characterization of the biosorbent was performed using the scanning electron microscope (SEM), the energy dispersive X-ray (EDX) and Fourier transform infrared (FT-IR) spectroscopy. Also, the the best conditions of experimental parameters were examined, and the reliability of the method developed was verified by applying the certified reference materials. Limit of detections (LODs) of the U(VI) and Th(IV) was calculated as 0.008 and 0.013 ng mL(-1) respectively. Relative standard deviations (RSDs) were found to be 1.6 and 2.4 %, respectively, for U(VI) and Th(IV). R-2 was also calculated as 0.9991. Preconcentration factors were achieved as 100 for both elements. It should be highlighted that LODs were critically improved and the sensitivity of ICP-OES was enhanced. (C) 2020 Elsevier B.V. All rights reserved.

The fungus Bovista plumbea immobilized on γ-Fe2O3 nanoparticles is shown to be a novel sorbent for magnetic solid-phase extractions of U(VI) and Th(IV). The biosorbent was characterized by FT-IR, SEM, and EDX. The effects of pH value, flow rate and volume of sample, amounts of biomass and support material, eluent type, foreign ions and repeated use of the sorbent on extraction efficiency were investigated. The sorption capacities are 41 and 44 mg g−1, respectively, for U(VI) and Th(IV). The results indicated that B. plumbea immobilized onto γ-Fe2O3 nanoparticles can be utilized as a novel material for the preconcentrations of U(VI) and Th(IV) in certified materials and in spiked tap, river and lake waters.

WOS: 000449346800022, PubMed ID: 30409581, Preconcentrations of Cu(II), Ni(II) and Pb(II) ions by using Coprinus silvaticus immobilized multiwalled carbon nanotube (MWCNT) were investigated. Effects of important parameters on preconcentration procedure were examined. The best pH values of for Cu(II), Ni(II) and Pb(II) were found to be 6.0, 6.0 and 4.0, respectively. Flow rate of sample solution was 2.0 mL min(-1), while desorption was achieved at 1.0 mL min(-1) flow rate. Preconcentration factors were achieved as 60 for Cu(II), Ni(II) and 70 for Pb(II) (by dividing initial sample volume to final volume). LODs were calculated as 0.014, 0.016 and 0.093 ng mL(-1), respectively for Cu(II), Ni(II) and Pb(II). Accuracy of the method was checked by applying to certified reference samples. Inductively coupled plasma optical emission spectrometer (ICP OES) was employed for measurements of Cu(II), Ni(II) and Pb(II) in digested baby food samples.

The utilization of the magnetized Pleurotus erygnii and Coprinus micaceus with γ-Fe2O3 nanoparticles as biosorbents for magnetic solid phase extraction (MSPE) of Cd(II) were investigated in details. The surface structures of magnetized P. erygnii and C. micaceus were investigated by the Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM) and energy dispersive X-ray (EDX). The best process conditions were tested and determined as pH 5, 3 mL min−1 flow rate, 100 mg of P. erygnii and C. micaceus on 75 mg of γ-Fe2O3 nanoparticles, 5 mL of 1 mol L−1 HCl as eluent, and 400 mL of sample volume for both biosorbents. The limit of detections (LOD) were achieved as 0.054 ng mL−1 and 0.040 ng mL−1 for magnetized P. erygnii and C. micaceus, respectively. Preconcentration factors were determined as 80 for both magnetized biosorbents. The recommended methods were validated using certificated reference materials. Cd(II) in different real samples were determined by ICP-OES (inductively coupled plasma optical emission spectrometry) after preconcentration with developed methods.

A method for preconcentration of Al(III) prior to its determination by inductively coupled plasma-optical emission spectrometry (ICP-OES) was developed because the sensitivity of ICP-OES is insufficient for trace-level measurement of Al(III). The method is based on the use of Coriolus versicolor}-immobilized $\gamma $-Fe$_{2}$O$_{3}$ magnetic nanoparticles as a solid phase sorbent. The best experimental conditions were found as pH 6.0, 2.0 mL/min flow rate, 100 mg amount of C. versicoloron 150 mg of $\gamma $-Fe$_{2}$O$_{3}$ nanoparticles, and 500 mL of sample volume. The Al(III) absorbed on biosorbent was eluted with 5.0 mL of 1.0 mol/L HCl. Limit of detection, limit of quantitation, linear range, correlation coefficient, relative standard deviation, and preconcentration factor were achieved as 0.03 ng/mL, 0.11 ng/mL, 0.2 to 20 ng/mL, 0.9994, 3%, and 100, respectively. Al(III) was preconcentrated in different water and food samples after successful results were achieved in the case of certified reference samples.

WOS: 000425615200008, Bacillus vallismortis and Bacillus mojavensis were loaded onto Amberlite XAD-4 resin and used for solid phase extraction (SPE) of uranium(VI). A quick and simple UV-Vis spectrophotometric method was used to determine U(VI) ion. The best experimental conditions were determined as being a pH of 5.0; a sample flow rate of 2.0 mL min(-1); 200.0 mg of biosorbent; 800 mg of Amberlite XAD-4, and 5.0 mL of 1 mol L-1 HCl as desorption solution for both immobilized bacteria. The preconcentration factors were achieved as 80 for both solid phase extractor. The developed methods were validated by applying to reference water and tea samples., Scientific Research Projects Unitof Siirt University, Turkey [BAP-2016-SIUFED-10], This study was supported by Scientific Research Projects Unitof Siirt University (Project code: BAP-2016-SIUFED-10), Turkey.

WOS: 000437262900016, PubMed ID: 30381167, This study deals with the preconcentrations of Ni(II) and Co(II) ions in real samples using the solid phase extraction method (SPE) before their determinations by inductively coupled plasma optical emission spectrometry (ICP-OES). Thermophilic bacterium Geobacillus stearothermophilus SO-20 (Accession number: KJ095002), loaded with Amberlite XAD-4, was utilized as a novel biosorbent. Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscope (SEM) were employed for the investigation of the bacterial surface before and after Ni(II) and Co(II) biosorption. The experimental parameters were examined to find the best conditions. The retained Ni(II) and Co(II) ions on the biosorbent were eluted by using 5.0 ml of 1.0 mol l(-1) HCI as the best eluent. The sorption capacities were found to be 16.8 mg g(-1) for Ni(II) and 21.6 mg g(-1) for Co(II). It was also successfully used for the quantification of Ni(II) and Co(II) in a river water sample, some vegetables and soil.

WOS: 000413291700070, PubMed ID: 29037726, Hybrid nanostructures composed of gamma-Fe2O3 (maghemite) and carboxylated-multi walled carbon nanotube (cMWCNT) were used for the magnetic solid phase extractions and determination of Sudan I, II, III, IV, Para Red, Sudan Black B and Sudan Red 7B in chili products. High performance liquid chromatography (HPLC) was employed for the measurements. Limit of quantification (LOQ) values were found in the range 0.44-2.82 ng mL(-1) for analytes. The best extraction parameters were determined as pH 8.0, 40 mg of magnetic nanoparticle, 4.0 min of contact time, 0.3 mL desorption by acetonitrile. The samples were dissolved in acetone-dichloromethane-methanol (3: 2: 1, v/v/v) and diluted with acetonitrile-methanol (v/v; 80: 20) before the method was applied. Concentrations of Sudan dyes and Para Red were determined in four samples of chili powder from less than LOQ to 31.21 +/- 1.6 ng g(-1), two samples of chili tomato sauces (lower than LOQ) and two samples of ketchup (lower than LOQ)., Mardin Artuklu University [MAU-BAP-14-SHMYO-09], The present work was carried out under the financial support of Mardin Artuklu University (MAU-BAP-14-SHMYO-09).

WOS: 000444967800031, PubMed ID: 30236672, 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., Mersin Technology Transfer Office Academic Writing Center of Mersin University, Turkey, This academic work was linguistically supported by the Mersin Technology Transfer Office Academic Writing Center of Mersin University, Turkey., C. micaceusMagnetic solid phase extractionPreconcentrationCo(II)Hg(II)

WOS: 000399510500023, PubMed ID: 28285087, Bioaccumulation, resistance and preconcentration of uranium(VI) by thermotolerant Bacillus vallismortis were investigated in details. The minimum inhibition concentration of (MIC) value of U(VI) was found as 85 mg/L and 15 mg/L in liquid and solid medium, respectively. Furthermore, the effect of various U(VI) concentrations on the growth of bacteria and bioaccumulation on B. vallismortis was examined in the liquid culture media. The growth was not significantly affected in the presence of 1.0, 2.5 and 5.0 mg/L U(VI) up to 72 h. The highest bioaccumulation value at 1 mg/L U(VI) concentration was detected at the 72nd hour (10 mg/g metal/dry bacteria), while the maximum bioaccumulation value at 5 mg/L U(VI) concentration was determined at the 48th hour (50 mg metal/dry bacteria). In addition to these, various concentration of U(VI) on alpha-amylase production was studied. The alpha-amylase activities at 0, 1, 2.5 and 5 mg/L U(VI) were found as 3313.2, 3845.2, 3687.1 and 3060.8 U/mg, respectively at 48th. Besides, uranium (VI) ions were preconcentrated with immobilized B. vallismortis onto multiwalled carbon nanotube (MWCNT) and were determined by UV-vis spectrophotometry. The surface macro structure and functionalities of B. vallismortis immobilized onto multiwalled carbon nanotube with and without U(VI) were examined by FT-IR and SEM. The optimum pH and flow rate for the biosorption of U(VI) were 4.0-5.0 and 1.0 mL/min, respectively. The quantitative elution occurred with 5.0 mL of 1 mol/L HCI. The loading capacity of immobilized B. vallismortis was determined as 23.6 mg/g. The certified reference sample was employed for the validation of developed solid phase extraction method. The new validated method was applied to the determination of U(VI) in water samples from Van Lake-Turkey. (C) 2017 Elsevier Ltd. All rights reserved.

WOS: 000329486800005, Solid-phase extraction method was developed for the preconcentration of thorium (Th). Fungal biomass Agaricus bisporus was immobilized to Amberlite XAD-4 as solid-phase sorbent. The critical parameters such as pH of the sample solution, flow rate of the sample, volume of the sample, and the effect of major ions that affect the preconcentration of thorium in this system were evaluated. The optimum pH for the sorption of Th is 6.0, and quantitative elution occurs with 1.0mol L-1HCl. The loading capacity was determined as 0.079mmol g(-1). The optimized method was validated through analysis of the certified reference material of tea leaves (NCS ZC73014) and successfully applied to the determination of Th in a real ore sample with satisfactory results.

Bu çalışmada, anason (Pimpinella anisum L.) ve kimyon (Cuminum cyminum L.) tohumlarının uçucu yağ bileşenleri ile bu yağların antimikrobiyal ve antioksidan özelliklerinin belirlenmesi amaçlanmıştır. Uçucu yağ bileşenleri GC/MS cihazı ile belirlenmiştir. Yağların antimikrobiyal özellikleri disk difüzyon yöntemi ile Gram pozitif (Staphylococcus aureus ATCC 25923, Streptococcus pyogenes ATCC 19615), Gram negatif (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853) bakterileri ve maya (Candida albicans ATCC 10231) kullanılarak, antioksidan özellikler ise DPPH yöntemiyle belirlenmiştir. Anason uçucu yağının esas bileşeninin trans-anetol (% 52.94) olduğu, bunu iso-anetol (% 13.89), karyofillen oksit (% 8.55) ve karyofillen (% 4.29)’in izlediği; kimyon uçucu yağının ise sırası ile ?-pinen (% 15.77), ?- terpinen (% 15.52), 1-fenil-1-butanol (% 15.13) ve kuminik aldehit (% 12.74) içerdiği saptanmıştır. Anason uçucu yağının mikroorganizmalar üzerinde düşük, kimyon uçucu yağının ise orta derecede antimikrobiyal aktivite gösterdiği saptanmıştır. Kimyon uçucu yağı C. albicans’a karşı 22±0.9 mm’lik inhibisyon zon çapı ile yüksek antimikrobiyal aktivite göstermiştir. P. aeruginosa her iki uçucu yağa karşı direnç göstermiştir. Kimyon uçucu yağının antioksidan aktivitesi (% 75.60) askorbik asit aktivitesine (% 78.75) yakın, BHA (% 50.45) ve BHT (% 23.54) aktivitesinden daha yüksek bulunmuştur. Anason düşük antioksidan aktivite (% 23.24) göstermiş olmasına rağmen BHT ile benzer aktivite göstermiştir. Çalışmada kullanılan örneklerin aktivite sıralaması askorbik asit>kimyon>BHA>BHT>anason şeklinde gerçekleşmiştir., In this research, the essential oil components, antimicrobial and antioxidant properties of anise (Pimpinella anisum L.) and cumin (Cuminum cyminum L.) seed oils were investigated. The essential oil components determined by GC/MS instrument. The antimicrobial activity determined by disc diffusion method against the gram negative bacteria, namely Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, the gram positive bacteria namely Staphylococcus aureus ATCC 25923, Streptococcus pyogenes ATCC19615 and Candida albicans ATCC10231 as the yeast. The antioxidant activities of essential oils were carried out by DPPH free radical scavenging activity method. It was determined that the main components of the anise essential oil were trans-anethole (52.94%) followed by iso-anethole (13.89%), caryophllene oxide (8.55%) and caryophyllene (29.4%); the main components of the cumin essential oil were β-pinene (15.77%), α-terpinene (15:52%), 1-Phenyl-1-butanol (15:13%), cumic aldehyde (12.74%) respectively. Anise essential oil showed weak antimicrobial activity and cumin essential oil showed moderate antimicrobial activity against test microorganisms. Cumin essential oil showed strong antimicrobial activity against C. albicans with 22±0.9 mm inhibition zone diameter. P. aeruginosa showed resistance to both essential oils. The antioxidant activity of cumin essential oil (75.60%) was observed closer to ascorbic acid (78.75%), higher than BHA (50.45%) and BHT (23.54%). Although anise essential oil exhibited low activity, it has the similar activity with BHT. The scavenging activity of the samples decreasing order was ascorbic acid> cumin >BHA>BHT> anise.

WOS: 000327367000003, Analytical performances of metal coated slotted quartz tube flame atomic absorption spectrometry (SQT-FAAS) and slotted quartz tube in situ atom trapping flame atomic absorption spectrometry (SQT-AT-FAAS) systems were evaluated for determination of Bi. Non-volatile elements such as Mo, Zr, W and Ta were tried as coating materials. It was observed that W-coated SQT gave the best sensitivity for the determination of Bi for SQT-FAAS and SQT-AT-FMS. The parameters for W-coated SQT-FAAS and W-coated SQT-AT-FAAS were optimized. Sensitivity of FAAS for Bi was improved as 4.0 fold by W-coated SQT-FAAS while 613 fold enhancement in sensitivity was achieved by W-coated SQT-AT-FAAS using 5.0 min trapping with respect to conventional FAAS. MIBK was selected as organic solvent for the re-atomization of Bi from the trapping surface. Limit of detection values for W-coated SQT-FAAS and W-coated SQT-AT-FAAS was obtained as 0.14 mu g mL(-1) and 0.51 ng mL(-1), respectively. Linear calibration plot was obtained in the range of 2.5-25.0 ng mL(-1) for W-coated SQT-AT-FAAS. Accuracy of the W-coated SQT-AT-FAAS system was checked by analyzing a standard reference material, NIST 1643e. (C) 2013 Elsevier B.V. All rights reserved., University of Dicle (DUBAP) [10-FF-31]; TUBITAK-BIDEP, The present work was carried out under the financial support of University of Dicle (DUBAP; 10-FF-31) and TUBITAK-BIDEP. The authors thank Dr. Murat Kaya from METU for his help in Raman studies.

A 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.

Five-step sequential extractions were employed to fractionation of Ni, Cr and Cu in soil polluted by anthropogenic activities and determine the mobility of the metals. Twelve samples were collected on an agricultural area that was located near an airport and intercity roads in Elazig-Turkey. Exchangeable, organically bounded, carbonate bounded, adsorbed species on Fe and Mn oxides and residual species (except silicates) of Ni, Cr and Cu were extracted into solution by using CaCl2 ,N a 4P2O7 ,N a 2EDTA, NH2OH–HCl and HNO3–H2O2, respectively. Mobile metal concentrations in fractions and total recoverable in soils were determined by using inductively coupled plasmaoptical emission spectrometry (ICP-OES). Total recoverable Ni, Cr and Cu concentrations were in the range of 40–119, 45–126 and 23–72 mg kg � 1 , respectively. It was observed that total concentrations of metals in some of the samples were higher than the permitted values. The sum of the mobile percentages of metals was found to be lower than 50%. The Ni, Cr and Cu percentages for exchangeable species are in the ranges of 0.18–1.64, 0.03–0.59 and 0.42–2.53%, respectively.

This review (160 refs). covers the current state of the art of microbacteria-based sorbents for preconcentration of metal ions at trace levels. We highlight advantages and major challenges of the techniques and discuss future perspectives of both batch and column-based methods. Particular attention is paid to the preconcentration of metal ions using resin-immobilized microbacteria for solid phase extractions. We also discuss detection methods including UV–vis spectrophotometry, FAAS, ICP-OES and ICP-MS. Analytical figures of merit are compared, and examples are given for the application to a variety of samples including food, beverages, alloys, water, soil, and geological samples.

WOS: 000384777400055, PubMed ID: 27542497, A novel solid phase extraction method was developed for simultaneous preconcentration-separation of Co2+, Cr6+, Hg2+ and Pb2+ ions prior to their determinations in food samples by ICP-OES. Thermophilic Bacillus altitudinis immobilized nanodiamond was used as a new biosorbent. SEM and FT-IR analysis were studied to characterize the biosorbent. The optimum pH values of quantitative biosorption for Co2+, Cr6+, Hg2+ and Pb2+ were found to be 5.0, 6.0, 6.0 and 6.0, respectively. A flow rate of 3.0 mL min(-1) was selected as optimum for all metal ions. 5 mL of 1 mol/L HCl was used as eluent. Preconcentration factor was achieved as 80. LODs were calculated as 0.071, 0.023, 0.016 and 0.034 ng mL(-1), respectively for Hg2+, Co2+, Cr6+ and Pb2+. The biosorption capacities were calculated for Co2+, Cr6+, Hg2+ and Pb2+ as 26.4, 30.4, 19.5, and 35.2 mg/g, respectively. The developed method was successfully applied to food samples to determine analyte concentrations. (C) 2016 Published by Elsevier Ltd.

In this study, bioaccumulation and heavy metal resistance of Cd2+, Cu2+, Co2+ and Mn2+ ions by thermophilic Geobacillus thermantarcticus and Anoxybacillus amylolyticus was investigated. The bacteria, in an order with respect to metal resistance from the most resistant to the most sensitive, was found to be Mn2+ > Co2+ > Cu2+ > Cd2+ for both G. thermantarcticus and A. amylolyticus. It was determined that the highest metal bioaccumulation was performed by A. amylolyticus in Mn2+ (28,566 μg/g dry weight), and the lowest metal bioaccumulation was performed by A. amylolyticus in Co2+ (327.3 μg/g dry weight). The highest Cd2+ capacities of dried cell membrane was found to be 36.07 and 39.55 mg/g membrane for G. thermantarticus and A. amylolyticus, respectively, and the highest Cd2+ capacities of wet cell membrane was found to be 14.36 and 12.39 mg/g membrane for G. thermantarcticus and A. amylolyticus, respectively.

Asphaltite, originating from petroleum, contains many kinds of mineral elements derived from its generation. These elements exist in different forms which may change throughout the asphaltite combustion process. Chemical fractionation of nickel (Ni) is necessary for risk assessment of asphaltite based bottom ash (ABBA). This study presents the concentration and fractionation of Ni in bottom ash of asphaltite (Sirnak, SE Anatolia, Turkey). Determination of total Ni in ash was performed in two stage microwave-acid digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES). Dry ashing is used for the almost complete elimination of organic materials prior to analyte determination. A seven-step sequential extraction process to fractionation of Ni from ABBA was investigated. Total Ni concentration in the ABBA was found to be 568.15 mg kg -1 . The most abundant form of Ni in the ABBA was Ni as sulfide (301.23 mg kg -1 ). Relative abundances of the remaining Ni fractions in ABBA follow the order: Reducible (83.23 mg kg -1 ) > Water soluble (77.94 mg kg -1 ) > Carbonate (35.67 mg kg -1 ) > Exchangeable (28.11 mg kg -1 ) > Oxidisable (25.19 mg kg -1 ) > Residual (16.78 mg kg -1 ). Assessment of chemical, mineralogical, morphological and

WOS: 000392037500051, PubMed ID: 27856038, In this study, uranium(VI) tolerance and bioaccumulation were investigated by using thermo-tolerant Bacillus mojavensis. The level of U(VI) was measured by UV-VIS spectrophotometry. The minimum inhibition concentration (MIC) value of U(VI) was experimented. Bacterial growth was not affected in the presence of 1.0 and 2.5 mg/L U(VI) at 36 h and the growth was partially affected in the presence of 5 mg/L U(VI) at 24 h. What was obtained from this study is that there was diversity in the various periods of the growth phases of metal bioaccumulation capacity, which was shown by B. mojavensis. The maximum bioaccumulation capacities were found to be 12.8, 22.7, and 48.2 mg/g dried bacteria, at 24th hours at concentration of 1.0, 2.5 and 5 mg/L U(VI), respectively. In addition to these, U(VI) has been pre-concentrated on B. mojavensis immobilized MWCNT. Several factors such as pH, flow rate of solution, amount of biosorbent and support materials, eluent type, concentration and volume, the matrix interference effect on retention have been studied, and extraction conditions were optimized. Preconcentration factor was achieved as 60. Under the optimized conditions, the limit of detection (LOD) and quantification (LOQ) were calculated as 0.74 and 2.47 mu g/L. The biosorption capacity of immobilized B. mojavensis was calculated for U(VI) as 25.8 mg/g. The results demonstrated that the immobilized biosorbent column could be reused at least 30 cycles of biosorption and desorption with the higher than 95% recovery. FT-IR and SEM analysis were performed to understand the surface properties of B. mojavensis. (C) 2016 Elsevier Ltd. All rights reserved.

Experimental variables in continuous flow hydride generation inductively coupled plasma-optical emission spectrometry (CF-HG-ICP-OES) were optimized for determination of bismuth. Concentrations of NaBH4, HCl, and NaOH, flow rates of NaBH4, sample solution, waste and carrier argon, radio frequency power, lengths of reaction, and stripping coils were optimized to obtain lower detection limits. Under optimum conditions, the detection limit was calculated as 0.16 ng mL−1, and the calibration plot was linear between 1.0–50.0 ng mL−1. An improvement in detection limit of 5.75 times by CF-HG-ICP-OES was reached vs. ICP-OES. Relative standard deviation (RSD) for ten replicate measurements of 10.0 ng mL−1 Bi was calculated as 3.9%. Effect of possible interferic ions on Bi signal was evaluated. Accuracy of method was verified by using a standard reference material, SRM 1643e. Results found for Bi were in satisfactory agreement with certified values. The proposed method was then employed to determine trace concentra...

Sensitivity of flame atomic absorption spectrometry (FAAS) for Bi determination was improved by slotted quartz tube (SQT) that was used also for atom trapping (AT). The trapped analyte was released by aspirating a small volume of organic solvent after a reasonable analyte collection time. Sensitivity was improved by 2.9 times by SQT-FAAS and 256 times by SQT-AT-FAAS with respect to FAAS. Optimum trapping period was found to be 6.0 min (36.0 mL of solution). Limit of detection (LOD) for SQT-AT-FAAS was found to be 1.6 ng mL− 1. %RSD was calculated as 4.0% for five replicate measurements of 7.5 ng mL− 1 Bi by SQT-AT-FAAS. Accuracy of the method developed was checked by analyzing a standard reference material of simulated fresh water (NIST 1643e) and result found was in good agreement with the certified one. The method can be applied in any laboratory equipped with a flame AA spectrometer. The consumption of time and sample volume is fairly low and application is simple and easy.

Geobacillus thermoleovorans subsp stromboliensis, was immobilized on an Amberlite XAD-4 ion exchanger and used as a solid phase extractant for the preconcentration of U(VI) ions prior to their determination by UV-VIS spectrophotometry. Parameters affecting the preconcentration (such as the pH value of the sample solution, the concentration of U(VI), the volume and type of eluent, the flow rate and the effect of potentially interfering ions) were studied. The optimum pH for the sorption of U(VI) was found to be pH 5.0. 5.0 mL of 1 M hydrochloric acid were used to eluate the U(VI) from the column. The loading capacity is 11 mg g−1. The limits of detection and quantification are 2.7 and 9.0 μg L−1, respectively, and relative standard deviations are

A new method based on the use of high-performance thin-layer chromatography (HPTLC) was developed for the simultaneous determination of the plant growth hormones, indole acetic acid, indole butyric acid, and absisic acid in in vitro seedling of watermelon. The measurements were performed at the associate maximum absorption wavelength of hormones. Calibration plots were constructed in the range of 50–600 ng per spot for indole acetic acid, 50–600 ng per spot for indole butyric acid, and 50–600 ng per spot for absisic acid. The limits of quantification (LOQs) determined experimentally were as follows: 10, 10, and 6 ng per spot, respectively, for indole acetic acid, indole butyric acid, and absisic acid. The method was successfully applied to watermelon tissues exposed to Cu2+, Co2+, and Pb2+ for determination of its indole acetic acid, indole butyric acid, and absisic acid concentrations.

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. © 2011 American Institute of Chemical Engineers Environ Prog, 2011

This study reports in vitro anticholinesterase, antioxidant and antimicrobial effects of the n-hexane, dichloromethane, ethanol and ethanol-water extracts prepared from Pistacia terebinthus L. fruits and Pistacia khinjuk Stocks seeds as well as their total phenolic and flavonoid contents, and fatty acid compositions. Ethanol and ethanol-water extracts of both species exhibited higher anticholinesterase activity than galanthamine. Among ABTS, DPPH and CUPRAC assays, the highest antioxidant capacity of the extracts was found in the last one. P. terebinthus ethanol extract being rich in flavonoid content showed the best cupric reducing effect. All extracts possessed no antimicrobial activity. The main fatty acid in P. terebinthus fruits (52.52%) and P. khinjuk seeds (59.44%) was found to be oleic acid. Our results indicate that P. terebinthus fruits and P. khinjuk seeds could be a good source of anticholinesterase compounds, and could be phytochemically investigated.

A method has been developed for the preconcentration of Th prior to its determination by UV-vis spectrophotometry after complexation with Arsenazo III. A column was packed with Amberlite XAD-4 resin containing immobilized Bacillus sp. as a solid phase extractant. Parameters such as pH of the solution and sample, the concentration of Th, the volume and type of eluent, flow rate and effect of matrix interference were studied. The optimum pH for the sorption of Th is 5.0, and quantitative eluation occurs with 1 mol L-1 HCl. The tolerance limits of some electrolytes were also studied. The loading capacity was determined to be 17.2 mg g−1. The method was applied to the determination of Th in real ore sample and validated by analyzing a certified reference samples (NCS DC-73350; poplar leaves).

Cadmium and nickel ions have been preconcentrated on Geobacillus thermoleovorans subsp. stromboliensis, immobilized on Amberlite XAD-4, and were determined by flame atomic absorption spectrometry (FAAS). Parameters such as pH, amount of adsorbent, eluent type and volume, flow rate of solution and the matrix interference effect on retention have been studied, and extraction conditions were optimized. Elution of Cd(II) and Ni(II) from minicolumns was carried out with 1.0 M hydrochloric acid or nitric acid with recoveries from 97 to 100%. The sorption capacity is 0.0373 and 0.0557 mmol g−1 for Cd(II) and Ni(II), respectively. The detection limits were 0.24 μg L−1 for cadmium and 0.3 μg L−1 for nickel. The relative standard deviations of the procedure were below 10%. The procedure was validated by analyzing certified reference materials and applied to the determination of Cd(II) and Ni(II) in natural water and food samples.

Biosorption of each of the ions Cd 2+ , Cu 2+ , Ni 2+ , Zn 2+ and Mn 2+ on Geobacillus toebii sub.sp. decanicus (G1) and Geobacillus thermoleovorans sub.sp. stromboliensis (G2) in a batch stirred system was investigated. The equilibrium adsorptive quantity was determined to be a function of the solution pH, contact time, biomass concentration, initial metal concentrations and temperature. The results obtained from biosorption experiments are used to understand the driving forces that govern the interaction between metal ions and a biosorbent. The experimental results were fitted well to the Scatchard plot, Langmuir, Freundlich, Dubinin–Radushkevich (D–R) isotherms. According to the parameters of the Langmuir isotherms, the maximum biosorption capacities of Cd 2+ , Cu 2+ , Ni 2+ , Zn 2+ and Mn 2+ for G2 were 38.8, 41.5, 42, 29 and 23.2 mg/g, respectively, while 29.2, 48.5, 21, 21.1 and 13.9 mg/g for G1, respectively. The mean free energy values evaluated from the D–R model indicated that the biosorptions of studied heavy metal ions onto bacteria were taken place by physical interaction. The biosorption mechanisms of studied metal ions on to the biosorbents were analysed by FT-IR spectra of G1 and G2 with and without metal ions. The first order and second order coefficients were obtained at 298, 308, 318 and 343 K. The experimental results were used to calculate the thermodynamic parameters.