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Öğe Anoxybacillus sp. SO B1-Immobilized Amberlite XAD-16 for Solid-Phase Preconcentration of Cu(II) and Pb(II) and Their Determinations by Flame Atomic Absorption Spectrometry(Taylor & Francis Inc, 2015) Oral, Elif Varhan; Ozdemir, Sadin; Dolak, Ibrahim; Okumus, Veysi; Dundar, Abdurrahman; Ziyadanogullari, Berrin; Aksoy, ZehraA new method for the determination of Cu(II) and Pb(II) by flame atomic absorption spectrometry (FAAS) after preconcentrating on a column containing Anoxybacillus sp. SO B1-immobilized Amberlite XAD-16 was developed. The functional groups of Anoxybacillus sp. SO B1 immobilized on Amberlite XAD-16 were characterized in KBr tablets by Fourier transform infrared (FT-IR) spectrometry. Various parameters such as pH, amount of the adsorbent, eluent type and volume, and flow rate of the sample solution were studied. The optimum pH values of quantitative sorption for Cu(II) and Pb(II) were found to be pH 7.0 and 5.0 and Cu(II) and Pb(II) ions could be quantitatively eluted with 5.0ml of 1.0mol L-1 HCI and 10.0ml of 0.25mol L-1 HNO3, respectively. Recoveries of Cu(II) and Pb(II) were found to be 100.9 +/- 1.57% and 100.3 +/- 0.49% (N = 5), the limits of detection of Cu(II) and Pb(II) in the determination by FAAS (3s, N = 10) were found to be 0.8 and 1.6 mu g L-1, respectively. The proposed enrichment method was applied for metal ion determination from water samples such as two parts of Tigris River water in Diyarbakir and Elazig, Lake of Hazar in Elazig, and tap water in Diyarbakir. Furthermore, the accuracy of the proposed method was verified by studying the analytical recovery and by analyzing certified reference material (NCS-DC 73350 leaves of poplar).Öğe Application of continuous wavelet transforms for simultaneous estimation of domperidone and lansoprazole in capsule formulations(Elsevier B.V., 2025) Ertekin, Zehra Ceren; Büker, Eda; Oral, Elif Varhan; Dinç, ErdalUV–Vis spectroscopy remains essential in pharmaceutical research and quality control due to its accessibility, simplicity, and effectiveness. However, overlapping spectra resulting from multicomponent drug formulations present challenges. Here, we describe a signal processing strategy using continuous wavelet transform (CWT) to resolve overlapping spectra of domperidone (DMP) and lansoprazole (LSP) for simultaneous quantification. Three different wavelet functions (Symlets 3, Coiflets 1, Daubechies 10), were found to be suitable for this purpose. Linear calibration curves were constructed using the CWT zero-crossing technique and the methods were validated by analyzing a set of synthetic mixtures, intra-and inter-day samples, and standard addition samples. The assay results of commercial capsule samples were compared with those obtained by derivative spectroscopy, and no significant statistical difference was observed. The proposed CWT methods demonstrated good compliance with the label claims and proved to be reliable, versatile, fast, and cost-efficient analytical methods without the need for preliminary separation procedures.Öğe Chemical Profile of Malva Neglecta and Malvella Sherardiana by LC-MS/MS, GC/MS and Their Anticholinesterase, Antimicrobial and Antioxidant Properties With Aflatoxin-Contents(Marmara Univ, Fac Pharmacy, 2017) Hasimi, Nesrin; Ertas, Abdulselam; Oral, Elif Varhan; Yener, Ismail; Alkan, Huseyin; Boga, Mehmet; Yilmaz, Mustafa AbdullahThe purpose of the present work was to determine the phenolic and the fatty acids profiles by LC-MS/MS and GC/MS with their antioxidant, anticholinesterase and antimicrobial activities, and aflatoxin contents of Malva neglecta and Malvella sherardiana. The phenolic contents of M. neglecta and M. sherardiana were determined by LC-MS/MS. Malic and 4-OH benzoic acids were found to be the most abundant compounds in M. neglecta and M. sherardiana, respectively. On the other hand, essential oil and fatty acid compositions were determined by GC/MS analysis. The methanol extracts of the plants showed the highest effect in all antioxidant assays in this study. The methanol extract of M. neglecta showed the highest activity among the petroleum ether, acetone, methanol and water extracts against acetyl-and butyryl-cholinesterase enzymes (53.68% and 63.95% inhibition ratio, respectively). The acetone extracts of M. neglacta and M. sherardiana exhibited moderate activity against C. albicans with 18 and 17 mm inhibion zone diameter, respectively. The results of the present study is also showed that the M. neglecta and M. sherardiana can also be used as a food source due to its high phenolic acid content and good antioxidant property. Also, the samples were aflatoxin free.Öğe Comparison of Methods for the Preconcentration of Cadmium (II) Using Amberlite XAD-16 Resin Modified with Anoxybacillus caldiproteolyticus and Geobacillus stearothermophilus as Novel Biosorbents(Taylor & Francis Inc, 2020) Enez, Baris; Oral, Elif Varhan; Fincan, Sema Aguloglu; Ziyadanogullari, BerrinThe isolation, identification and characterization of bacteria obtained from soil of Ergani Makam Mountain were performed and the results revealed that the bacteria were thermophilic Anoxybacillus caldiproteolyticus. The characterized bacteria and purchased Geobacillus stearothermophilus were immobilized on Amberlite XAD-16 in order to prepare two biosorbents for preconcentration experiments for the determination of cadmium (II) ions. The produced biosorbents were enriched separately using mini-columns and the analyte was determined by flame atomic absorption spectrometry. The effects of solution parameters were investigated for the separation and preconcentration yields. The recovery efficiencies of Amberlite XAD-16 immobilized separately with A. caldiproteolyticus and G. stearothermophilus were determined to be 98.23 +/- 2.40 and 98.93 +/- 1.3 (n = 5) for the optimum working conditions, respectively. Moreover, the Cd (II) ion was recovered with 10 mL of 1 mol L-1 of HCl and 2 mL of 0.5 mol L-1 HNO3 solutions. The optimum working conditions were determined to be at pH 6.0 and a flow rate of 2 mL min(-1) for both biosorbents. The recovery efficiencies of matrix ions were characterized to investigate the feasibility of the developed preconcentration methods. The accuracy of the proposed methods were controlled by analyzing a SCP Science EnviroMAT Waste Water, Low (EU-L-2) certified reference material. The obtained results were comparable to the certified values. These methods were also applied to the analysis of water samples from Dicle River, Hazar Lake and Diyarbakir tap water for Cd (II).Öğe Comparison of Modified Tessier and Revised BCR Sequential Extraction Procedures for the Fractionation of Heavy Metals in Malachite Ore Samples Using ICP-OES(Atomic Spectroscopy Press Ltd, 2019) Oral, Elif VarhanIn this study, two sequential extraction procedures (modified Tessier procedure and revised BCR procedure) were applied for the decomposition of Fe, Cu, Co, Pb, Zn, and Mn in the structure of malachite ore from the Keban region of Turkey. The effects and efficiency of each extraction step used in these procedures were examined. Metals analysis was performed by ICP-OES. Due to the differences in the binding forms of the metals existing in the structure of the ore and the different properties of reagents used, the concentrations of the metals were different in the extraction steps of both procedures. When the results were examined, it was found that the metal concentrations passing to the solution in each extraction step of the modified Tessier procedure were much higher than of the revised BCR procedure. Thus, it was concluded that the modified Tessier procedure is more suitable for decomposing metals in malachite ore.Öğe Comparison of Two Sequential Extraction Procedures for Trace Metal Partitioning in Ore Samples From the Keban Region in Elazig, Turkey(Atomic Spectroscopy Press Ltd, 2018) Oral, Elif VarhanThe objective of this research was to compare two sequential extraction procedures, modified Tessier and revised BCR, for the fractionation study of Fe, Cu, Co, Pb, Zn, and Mn in ore samples obtained from the Keban Region, Turkey. The efficiency and suitability of these procedures and their corresponding extraction steps for partitioning the heavy metals bound to the solid forms were tested. Metal analysis was carried out by inductively coupled plasma optical emission spectrometer (ICP-OES). The two procedures were examined and showed that there are differences in the bonding forms of the metals to ore and in the properties of the reactants used. Because of these differences, the amount of metals passing through the solution are different in the two procedures.Öğe Complexation and transport of amino acid esters and their salts with synthesised chiral novel aza crown ether derivatives(Taylor & Francis Ltd, 2014) Kazaylek, Mehmet; Kocakaya, Safak Ozhan; Oral, Elif Varhan; Colak, Mehmet; Karakaplan, MehmetThe syntheses of four aza-15-crown-5 ethers bearing phenyl and phenoxymethyl moieties attached to a stereogenic centre on the crown ring were achieved. Macrocycles have exhibited strong binding ability (K-a=5364-12,969M(-1)) and modest enantiomeric discrimination towards the enantiomers of amino acid methyl ester salts by UV titration method in CHCl3 at 25 degrees C. Computer modelling results supported experimental data providing a detailed understanding of the molecular recognition mode between hosts and guests and the likely binding sites involved. Macrocycles were used for chiral discrimination of amino acids in their zwitterionic forms or as potassium and sodium salts in transport experiments across a bulk chloroform membrane with satisfactory selectivity.Öğe A new method for preconcentration of Th(IV) and Ce(III) by thermophilic Anoxybacillus flavithermus immobilized on Amberlite XAD-16 resin as a novel biosorbent(Elsevier Science Bv, 2017) Yener, Ismail; Oral, Elif Varhan; Dolak, Ibrahim; Ozdemir, Sadin; Ziyadanogullari, RecepA novel approach has been improved for the preconcentration of Th(IV) and Ce(III) by using thermophilic Anoxybacillus flavithermus which were immobilized on Amberlite XAD-16 resin and analyzed by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). The concentration of Th(IV) and Ce(III), the eluent type and volume, the pH of model solutions, influences of matrix interference parameters, and flow rate were analyzed and optimized extraction conditions were determined. The optimum pH for quantitative sorption of Th(IV) and Ce(III) was found as 7.0 and elution of Th(IV) and Ce(III) from mini-columns was studied with 1.0 mol L-1, 5 mL HNO3 with recoveries from 100%. The precision of this method was validated by comparing the analytical recovery and certified reference materials (IAEA Soil-7). Finally, this enrichment method was used to determine Th(IV) and Ce(III) in bastnaesite ore sample. (C) 2017 Elsevier B.V. All rights reserved.Öğe Nutritional composition of potato (Solanum tuberosum L.) Haulms(Mattioli 1885, 2018) Kaplan, Mahmut; Ulger, Ismail; Kokten, Kagan; Uzun, Sati; Oral, Elif Varhan; Ozaktan, Hamdi; Temizgul, RidvanThe present study was conducted to investigate the nutritional composition of the haulms of commonly grown 5 potato (Solanum tuberosum L.) cultivars (Milva, Laura, Granola, Europrima and Jelly). Plant materials were harvested from potato production fields of Efsane Seed Company just before tuber harvest. Current findings revealed that green herbage yields of potato haulms varied between 416.51 and 670.32 kg/ da, dry herbage yields between 381.62 and 527.24 kg/da, crude protein (CP) ratios between 10.85-14.48%, crude ash (CA) ratios between 5.22 and 9.10%, acid detergent fiber (ADF) ratios between 22.46 and 33.94%, neutral detergent fiber (NDF) ratios between 47.99 and 60.91%. Gas production values varied between 33.15 and 47.56 mL, methane productions between 5.27 and 8.35 mL, metabolic energy (ME) values between 7.45 and 9.29 MJ/kg DM and organic matter digestibility (OMD) values between 50.77-63.69%. Considering the mineral content of potato haulms, iron contents varied between 47.35 and 180.07, manganese contents between 28.14 and 85.15, cobalt contents between 0.43 and 1.13, nickel contents between 3.40 and 8.60, copper contents between 10.84 and 15.35, zinc contents between 4.14 and 15.60, cadmium contents between 1.02 and 1.55 and lead contents between 6.74 and 9.80 mg/kg/DM. It was concluded based on current findings from the haulms of five different potato cultivars that haulms had quite high feed quality values. With rich mineral contents, haulms may eliminate supplementary mineral requirements of live stock. Therefore, it can be stated that haulms of all five cultivars can be used as an alternative feed source for animals.Öğe Phytochemical profile and some biological activities of three Centaurea species from Turkey(Pharmacotherapy Group, 2016) Boga, Mehmet; Alkan, Huseyin; Ertas, Abdulselam; Oral, Elif Varhan; Yilmaz, Mustafa A.; Yesil, Yeter; Goren, Ahmet C.Purpose: To characterise the phytochemical profile of whole plants of Centaurea balsamita, C. depressa and C. lycopifolia with LC-ESI-MS/MS, and as well as their antioxidant, anticholinesterase and antimicrobial activities. Methods: Organic and aqueous extracts of the three Centaurea species were evaluated for DPPH free radical, ABTS cation radical scavenging and cupric reducing antioxidant capacity (CUPRAC). Acetyl-and butyryl-cholinesterase enzyme inhibition abilities of the extracts using petroleum ether, acetone, methanol and water were studied to determine anticholinesterase activity, while antimicrobial activity was determined by disc diffusion method using appropriate antimicrobial standards and organisms. The phytochemical components of the methanol extracts were assessed by LC-MS/MS. Results: The methanol extract of C. balsamita exhibited much higher DPPH free and ABTS cation radicals scavenging activities (with IC50 of 62.65 +/- 0.97 and 24.21 +/- 0.70 mg/ml, respectively) than the other extracts. The petroleum ether extracts of the plant species exhibited moderate inhibitory activity against butyrylcholinesterase enzymes while the acetone extract of C. balsamita showed good antifungal activity against Candida albicans. Quinic acid (17513 +/- 813 mu g/g, 63874 +/- 3066 mu g/g and 108234 +/- 5195 mu g/g) was the major compound found in the methanol extracts of C. balsamita, C. depressa and C. Lycopifolia, respectively. Conclusion: These results indicate quinic acid is the major compound in the three plant species and that Centaurea balsamita has significant antioxidant, anticholinesterase and antimicrobial properties. Further studies to identify the compounds in the extracts responsible for the activities are required.Öğe Selective in vitro and in silico enzymes inhibitory activities of phenolic acids and flavonoids of food plants: Relations with oxidative stress(Elsevier Sci Ltd, 2020) Yener, Ismail; Kocakaya, Safak Ozhan; Ertas, Abdulselam; Erhan, Bahadir; Kaplaner, Erhan; Oral, Elif Varhan; Yilmaz-Ozden, TugbaIn this study, the inhibitory potentials of food originated 34 phenolic acids, and flavonoid compounds were screened against acetylcholinesterase, butyrylcholinesterase, urease, and tyrosinase enzymes. All compounds included in this study exhibited high antioxidant activity with an ignorable cytotoxic activity. In general, they also showed poor anti-urease and anti-tyrosinase activities. Compounds in aglycone form (quercetin, myricetin, chrysin, and luteolin) showed strong anticholinesterase activities. No relation was observed between the tested bioactivities except from the case that aglycone compounds exhibited a strong positive relationship between antioxidant activities and anticholinesterase activity. Interestingly, there was a relation between the molecular weights of aglycone compounds and their anticholinesterase activities. The study showed that flavonoids with molecular mass of 250-320 g/mol have high potential of anticholinesterase activities and are valuable for future experiments on animals and humans. Potential inhibitory effects of these molecules on target proteins were investigated using docking and molecular dynamics calculations.Öğe Selective in-vitro Enzymes' Inhibitory Activities of Fingerprints Compounds of Salvia Species and Molecular Docking Simulations(Shaheed Beheshti Univ, Sch Pharmacy, 2020) Kocakaya, Safak Ozhan; Ertas, Abdulselam; Yener, Ismail; Ercan, Bahadir; Oral, Elif Varhan; Akdeniz, Mehmet; Kaplaner, ErhanRecently Nutrition and Food Chemistry researches have been focused on plants and their products or their secondary metabolites having anti-alzheimer, anti-cancer, anti-aging, and antioxidant properties. Among these plants Salvia L. (Lamiaceae) species come into prominence with their booster effects due to high antioxidant contents, which have over 900 species in the world and 98 in Turkey. Some Salvia species are already in use as herbal treatment of vessel stiffness, Dementia like problems and cancer. Recently some species of Salvia are of extensive research topic. In this study, inhibitory potentials of secondary metabolites, rosmarinic acid, salvigenin, salvianolic acid A and B, tanshinone I and IIA, cyrtotanshinone, dihydrotanshinone I, carnosic acid, carnosol, and danshensu sodium salt were investigated against acetylcholinesterase, butyrylcholinesterase, urease and tyrosinase enzymes both in-vitro and in slico in detail. Elevated inhibitory effects on acetyl-and butyryl-cholinesterase of dihydrotanshinone I (IC50: 1.50 +/- 0.02 and 0.50 +/- 0.01 mu g/mL, respectively), carnasol (IC50: 11.15 +/- 0.05 ve 3.92 +/- 0.03 mu g/mL) and carnosic acid (IC50: 31.83 +/- 0.65 ve 4.12 +/- 0.04 mu g/mL) were observed. Furthermore, all other secondary metabolites were active against butyrylcholinesterase. Anti-urease (42.41 +/- 0.85%) and anti-tyrosinase (39.82 +/- 1.16%) activities of tanshinone I were also observed. Potential inhibitory effects of these molecules on target proteins were investigated using DOCK and molecular dynamics calculations. Dock score analysis and Lipinski parameters were demonstrated that these ligands are potential inhibitors against relevant enzymes. Our findings suggest that Salvia species can be utilized as a ptential source of anti-alzheimer active compounds for designing novel products.Öğe Trace Element Analysis by ICP-MS and Chemometric Approach in Some Euphorbia Species: Potential to become a Biomonitor(Shaheed Beheshti Univ, Sch Pharmacy, 2019) Yener, Ismail; Temel, Hamdi; Tokul-Olmez, Ozge; Firat, Mehmet; Oral, Elif Varhan; Akdeniz, Mehmet; Senturk, KeremIn this study, the branch, leaves, flowers, roots and mixed parts of different nine Euphorbia species were analyzed for their trace element contents by using ICP-MS. The samples were digested by concentrated nitric acid and hydrogen peroxide in a microwave by ICP-MS before the analysis. The accuracy and precision of the method was evaluated by CRM 1573a Tomato Leaves. Trace element contents accumulated in different parts of each sample were contrasted. Minitab Statistical Software Inc., programme was used for the multivariate analysis of 12 toxic metals of seeds, roots, branches, leaves, flowers, and mixed parts of Euphorbia species collected from Diyarbakir, Kayseri, Malatya, Mardi'', Trabzon, and Van cities.When the studied Euphorbia species are compared in terms of their metal contents; V, Tl, Cr, and Ni metals in E. eriophora, Ba in E. aleppica, As and Co metals in E. segtieriana, Ag and Se metals in E. craspedia, Cu and Cd metals in E. fistulosa, Cs and Pb metals in E. grisophylla, Zn in E. macroclada and also Rb and Sr metals in E. denticulata were determined higher. It was determined that the studied species accumulated some metals at highly amounts especially in the root and leaf parts. In general, it can be said that Euphorbia species have high potential to become a biomonitor. For this reason, it can be predicted that these species will be used as ornamental plants in landscape architecture due to both their toxic metals retention properties and their beautiful appearance.Öğe Trace element analysis in some salvia species by inductively coupled plasma-mass spectrometry (Icp-ms) and chemometric approach(Marmara University, 2020) Tunay, Zeki; Yener, İsmail; Oral, Elif Varhan; Demirkoz, Aslı Barla; Ölmez, Özge Tokul; Fırat, Mehmet; Öztürk, Mehmet; Aydın, Işıl; Aydın, Fırat; Ertaş, AbdülselamIn this study, the stems, leaves, flowers, roots and mixed all parts of five Salvia species were analyzed for their trace element (Li, Be, V, Cr, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Ag, Cd, Cs, Ba, Hg, Tl, Pb, and U) contents using ICP-MS. The seeds, roots leaves, flowers, and mixed parts of each species were digested by concentrated nitric acid and hydrogen peroxide in a microwave by before ICP-MS the analysis. The accuracy and precision of the method were evaluated by CRM 1573a Tomato Leaves. Trace element contents in different parts of each sample were compared. Concentration of toxic elements (As, Cd, Hg and Pb) were lower than those declared by WHO, except Cr content. Cr content in the root sections of Salvia suffruticosa (SFR), S. hydrangea (SHR), S. trichoclada (STR), S. xanthocheila (SXR), leaf samples of S. kronenburgii (SKL) and S. xanthocheila (SXL). also the Cr content in the leaf sections of Salvia kronenburgii (SKL) Salvia xanthocheila (SXL) was found high. When consider the daily metal (Zn, Cu, Sr, Ba and Ni) needs It was concluded that these Salvia species can be nutritive sources. In addition, Salvia samples were classified by utilizing chemometric techniques such as Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA). While the first two main components explained 55.30% of the total variance, the first six main components explained 89.60% of total variance. © 2020 Marmara University Press.Öğe Trace Elemental Analysis of Allium Species by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) with Multivariate Chemometrics(Taylor & Francis Inc, 2019) Oral, Elif Varhan; Tokul-Olmez, Ozge; Yener, Ismail; Firat, Mehmet; Tunay, Zeki; Terzioglu, Pinar; Aydin, FiratAerial parts and roots of the 12 Allium species collected from five localities of Turkey were studied for trace elements (Ag, As, Cd, Co, Cr, Cu, Ni, Pb, Se, Tl, V, and Zn) using inductively coupled plasma mass spectrometry (ICP-MS). A tomato leaves certified reference material was used to characterize the accuracy and precision of the analysis. Each Allium species contained Se (315-2740 mu g/kg), Tl (2.75-71 mu g/kg), V (77-6790 mu g/kg), and Zn (3.73-26.6 mg/kg) which can meet the necessary daily intake of these minerals. In addition, chemometric analyses were performed using correlation analysis, principal component analysis, and hierarchical cluster analysis to determine the association of 12 trace elements in the Allium species. Using chemometrics, the distribution of elements between aerial parts and roots, and geographic collection localities of Allium species were also examined. This study is important the consumers because of the wide consumption of Allium species. This report is the first detailed characterization of the metal content of Allium species.
