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Öğe THE EFFECT OF UV-B ON FATTY ACID CONTENT AND RADICAL SCAVENGING ACTIVITY OF METHANOLIC EXTRACTS FROM Hypericum retusum Aucher GROWN UNDER IN VITRO CONDITIONS(Parlar Scientific Publications (P S P), 2013) Isikalan, Cigdem; Karakus, Pinar; Kuru, Ibrahim Selcuk; Celik, Kadir SerdarThe study was aimed to evaluate the effects of UV-B radiation on fatty acid content and antioxidant activity of a methanolic extract of Hypericum retusum Aucher plantlets grown under in vitro conditions. Therefore, the plantlets were exposed to UV-B radiation for different durations (Ti: 15, T-2: 30, T-3: 45, T-4: 60 min) The UV-B application led to increase in linolenic (42.84%), oleic (6.92%) and linoleic acid (28.48%) in H. retusum. The methanol extracts of plantlets grown in vitro conditions showed the strongest free radical scavenging activities at concentrations of 50, 100, and 300 mu g/mL(-1). It has been found that UV-B radiation and in vitro growth conditions have a significant effect on the accumulation of fatty acids. However, the free radical scavenging ability of H. retusum extract was decreased after UV-B application.Öğe Geochemical Multi-element ICP-OES Analysis of Borehole Waters from SE Anatolia(Atomic Spectroscopy Press Ltd, 2016) Duz, M. Zahir; Sagirdag, Mehmet; Celik, Kadir Serdar; Hasan, Mahmood A.; Kilinc, ErsinWater supply from boreholes is today used by people from rural areas of Turkey more commonly due to the reduction of available surface water. For this reason, the concentrations of Al, As, B, Be, Ca, Cd, Co, Cr, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, Pb, Se, Sn, and Zn in borehole waters of the Diyarbakir province (SE Anatolia) were determined in this study. Thirty borehole waters were sampled from different towns and villages. The samples were analyzed by inductively coupled plasma optical emission spectrometry (ICP-OES). The results of the analyses were compared with guidelines as set by Turkey, the WHO, and the EU. From the results it could be concluded that the ICP-OES method can be considered useful for the routine determination of trace elements in waters and similar matrices. For quality control purposes, the certified reference material TMDW-B Drinking Water was employed for validation. The recovery values were in the range of 93-101%. The Al, As, B, Be, Cd, Co, Cr, Hg, Mn, Mo, Ni, Pb, and Sn concentrations in the samples were found lower than the recommended LOD. The concentrations found were in the range of 12.71-111.4 mg/L for Na, 0.76-3.07 mg/L for K, 9.62-115.5 mg/L for Ca, 2.69-41.85 mg/L for Mg, 10 mu g/L.Öğe Selective preconcentration of Lanthanum(III) by Coriolus versicolor immobilised on Amberlite XAD-4 and its determination by ICP-OES(Taylor & Francis Ltd, 2014) Ozdemir, Sadin; Okumus, Veysi; Dundar, Abdurrahman; Celik, Kadir Serdar; Yuksel, Uyan; Kilinc, ErsinCoriolus versicolor, a wood fungus, was immobilised on Amberlite XAD-4 and used as solid-phase biosorbent for preconcentrations of rare earth elements. La(III), Th(IV), U(IV) and Ce(III) were subjected to solid-phase extraction procedure. We observed that La(III) was selectively preconcentrated, while other ions remained in solution at pH 6.0. 5.0mL of 1.0molL(-1) HCl was used to elaute La(III) from column. 250mg of C. versicolor loaded on 1000mg of XAD-4 was optimised as solid-phase matrix. Concentrations of ions in solutions were determined by inductively coupled plasma- optical emission spectrometry (ICP-OES). The calibration plot after preconcentration was linear in the range from 1.0 to 50.0ngmL(-1) for La(III). Limit of detection was found as 0.27ngmL(-1) for La(III) by SPE method. Relative standard deviation was found lower than 6.7% for 1.0ngmL(-1) of La(III) solution (n=10). The sensitivity of ICP-OES was improved by a factor of 46.8. The applicability of the method was validated through the analysis of certified reference samples of tea (NCS ZC-73014) and spinach (NCS ZC-73013).