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Öğe The effect of Plantago major Linnaeus on serum total sialic acid, lipid-bound sialic acid, some trace elements and minerals after administration of 7,12-dimethylbenz(a)anthracene in rats(SAGE, 2012-04) Oto, Gökhan; Ekin, Suat; Özdemir, Hülya; Levent, Abdulkadir; Berber, İsmetThe present study was designed to evaluate the effect of Plantago major Linnaeus (PM) extract on serum total sialic acid (TSA), lipid-bound sialic acid (LSA), some trace elements (copper (Cu), zinc (Zn) and iron) and mineral levels (magnesium, calcium and sodium) in Wistar albino rat administrated 7,12-dimethylbenz(a)anthracene (DMBA). Rats were divided into three equal groups (n = 6). Group I comprised the control group, group II was treated with DMBA (100 mg/kg, single dose) and group III was treated with DMBA (100 mg/kg single dose) and aqueous extract of PM 100 mg/kg/day for 60 days. After 60 days, statistical analyses showed that TSA and LSA levels in DMBA and DMBA + PM groups were significantly higher compared to the control group (TSA: p < 0.01, p < 0.05; LSA: p < 0.05, p < 0.05, respectively). Serum Zn levels were decreased in subjects treated with DMBA (p < 0.01) and DMBA + PM (p < 0.05) compared to the control group values. Serum Cu levels were increased in DMBA group and PM-treated group compared to the control group values. The results of this investigation showed that the levels of TSA and LSA changed significantly, which are sensitive markers for detecting the toxic effects of DMBA. On the other hand, observed decline in Zn levels in rats from DMBA + PM group might be due to decreased generation of free radicals and oxidative stress. Results from this study suggest that PM may be partially effective in preventing carcinogenesis initiated by environmental carcinogen DMBA.Öğe Fluorescence properties and electrochemical behavior of some schiff bases derived from n-aminopyrimidine(Springer Nature, 2014-03) Gülcan, Mehmet; Doğrul, Ümit; Öztürk Ürüt, Gülsiye; Levent, Abdulkadir; Akbaş, EsvetA series of Schiff bases (L 1, L 2 and L 3 ) were prepared by refluxing aromatic aldehydes with N-Aminopyrimidine derivatives in methanol and ethanol. The structures of synthesized compounds were characterized by FTIR, 1H NMR, 13C NMR and microanalysis. The electrochemical behaviors of the Schiff base ligands were also discussed. Moreover, the evaluation of absorption and emission properties of the structures were carried out in five different solvents. The products show visible absorption maxima in the range of 304-576 nm, and emission maxima from 636 to 736 nm in all solvents tested.Öğe The varieties and characteristics of grapes grown in Southeast Anatolia Region(Batman Üniversitesi, 2020-12-31) Levent, Abdulkadir; Demir, ZülküfGrape is a fruit, called Vitis. Turkey replaces in the first sixth in growing grape, in the world. Grape has a significant place in the food industry. The antioxidants in grape seed have the effect of preventing and treating many diseases. In Turkey, the percentages of grapes, consumed in the form of wort, is about 30 %, annually. The 25 % of grape garbage is seeds. Approximately 3-6 % of grapes seeds (44000 tons) wasted annually. The foreseeing designing and manufacturing the grape squeezing machine will facilitate the work of the grape grower and will achieve the grape seeds to the economy. While the sieve diameter of grape seeds separator, separated the seeds from the garbage of the grape will be less than or equal to 2 mm (≤2 mm), the garbage from the wort is greater than or equal to 8.5 mm (≥8.5 mm), according to the seeds geometrical dimensions, gained.Öğe Silica gel-immobilized 5-aminoisophthalohydrazide: A novel sorbent for solid phase extraction of Cu, Zn and Pb from natural water samples(Wiley Online Library, 2020-03-11) Aydın, Funda; Çakmak, Reşit; Levent, Abdulkadir; Soylak, MustafaA novel silica sorbent, silica gel‐immobilized 5‐aminoisophthalohydrazide (SiO2‐APH), was prepared by the condensation of 3‐chloropropyl‐functionalized silica gel with 5‐aminoisophthalohydrazide (APH) derived from dimethyl 5‐aminoisophthalate as a starting material and used for separation and preconcentration of Cu, Zn, and Pb metals in water samples using Flame Atomic Absorption Spectrometry (FAAS). The characterization of the new sorbent was carried out by Elemental Analysis, Thermogravimetric Analysis (TGA) and Fourier Transform Infrared Spectroscopy (FTIR). Important analytical parameters including as pH, amount of sorbent, type and amount of eluting solvent, sample volume, vortex and ultrasonic bath time, matrix ions that effect the developed SiO2‐APH‐solid phase extraction (SPE) method were investigated and optimum parameters were detected. Recoveries of examined metals were obtained as 98% for Cu and Pb and 101% for Zn. The relative standard deviation (RSD, n = 8) of Cu, Zn and Pb metals were 3.2, 2.8 and 1.6%, respectively. Limit of detections (LODs) (n = 10) were found as 2.7 μg L−1 for Cu, 7.4 μg L−1 for Zn and 3.5 μg L−1 for Pb μg L−1. The accuracy of the new method was assessed by analyzing of TMDA‐51.4 and TMDA‐70.2 certified reference materials. The results obtained for metals were in a good agreement with certified values. Addition/recovery test was applied to the real well, river, dam and stream water samples to check the accuracy of the method. The results showed that the developed SiO2‐APH‐SPE method can be effectively used as an alternative method for determination of Cu, Zn, and Pb metals in water samples.Öğe Voltammetric behavior of testosterone on bismuth film electrode: Highly sensitive determination in pharmaceuticals and human urine by square‐wave adsorptive stripping voltammetry(Wiley Online Library, 2015-03-20) Levent, Abdulkadir; Altun, Ahmet; Taş, Süleyman; Yardım, Yavuz; Şentürk, ZühreIn this paper, an electrochemical application of bismuth‐film electrode (BiFE) fabricated via ex‐situ electrodeposition onto a glassy carbon electrode for testosterone determination was investigated in aqueous and aqueous/surfactant solutions. In cyclic voltammetry, the compound showed one irreversible and adsorption‐controlled reduction peak. The BiFE revealed good linear response in the examined concentration range of 1 to 45 nmol L−1 testosterone in BrittonRobinson buffer, pH 5.0 containing 3 mmol L−1 cetyltrimethylammonium bromide. The limit of detection was 0.3 nmol L−1 (0.09 ng mL−1). Finally, the BiFE was satisfactorily applied for quantitation of testosterone in both pharmaceutical (oil‐based ampoule) and biological (human urine) samples.Öğe Voltammetric behavior of acebutolol on pencil graphite electrode: highly sensitive determination in real samples by square‑wave anodic stripping voltammetry(Iranian Chemical Society, 2017-08-22) Levent, AbdulkadirIn this work, an electrochemical investigation of acebutolol (ACE), a beta-blocker drug, was carried out in alkaline medium using pencil graphite (PG) electrode. In cyclic voltammetry, the compound displayed a reversible and adsorption-controlled oxidation peak. By using squarewave anodic stripping voltammetry, the oxidation peak current observed at +0.78 V showed a linear relationship with concentration at 0.4–7 nM interval in Britton–Robinson bufer (pH 10.0) and a detection limit of 0.09 nM. The relative standard deviation of 4.72% for the concentration level of 2.0 nM (n = 11) was also calculated. The PG electrode that is used for the frst time in this method was successfully applied to determine the ACE in pharmaceutical formulations and urine.Öğe Synthesis, characterization, quantum chemical studies and electrochemical performance of new 4,7-dihydrotetrazolo[1,5-a]pyrimidine derivatives(SpringerLink, 2019-03-22) Akbaş, Esvet; Çelik, Savaş; Ergan, Erdem; Levent, AbdulkadirIn this study, 4,7-dihydrotetrazolo[1, 5-a]pyrimidine derivatives (1–5) were prepared via Multicomponent Cyclocondensation Reactions (MCRs). All structures were determined by using FT-IR, 1H/13C NMR and elemental analyses. The compounds were investigated as corrosion inhibitors using density functional theory (DFT) at the level of B3LYP/6-31G (d, p). According to the calculations, compound 1 appears to be a good inhibitor for corrosion. In addition, the electrochemical properties of the novel systems were investigated by CV.Öğe Bor katkılı elmas elektrot ile naftalin’in voltametrik davranışı: Kare dalga anodik sıyırma voltametrisi ile miktar tayini(Süleyman Demirel Üniversitesi, 2017-04-28) Levent, AbdulkadirBu çalışmada, Naftalin bor katkılı elmas elektrot yüzeyindeki elektrokimyasal özellikleri, değişik çözelti ortamları ve geniş bir pH aralığında incelenmiştir. İlk olarak çalışma elektrotun performansını etkileyen değişkenler (destek elektrolitinin seçimi, elektrot temizleme yöntemi, iyon şiddeti ve pH, biriktirme/ölçüm çözeltisinin bileşimi, biriktirme gerilimi/süresi, voltametrik dalga formu değişkenleri); voltametri ve/ya da sıyırma voltametrisi teknikleri kullanılarak ayrıntılı olarak araştırılmıştır. Daha sonra önerilen yöntemlerin elde edilen optimum koşullarda Naftalin için doğrusallık (0.9-4.5 µM), saptama sınırı (LOD; 0.225 µM) ve kesinlik (% BSS 2.26) açısından validasyonu gerçekleştirilmiştir. Geliştirilen KD-ASV yöntemi, çeşme suyunda naftalinin analizi için standart katma yöntemi kullanılarak başarılı bir şekilde uygulanmıştır.Öğe Electrochemical performance of boron-doped diamond electrode in surfactant-containing media for ambroxol determination(Elsevier, 2014-07-17) Levent, Abdulkadir; Yardım, Yavuz; Şentürk, ZühreA novel application of boron-doped diamond electrode is introduced for the determination of ambroxol, a potential antioxidant drug belonging to the expectorant class. The electrochemical oxidation of ambroxol was first investigated by cyclic voltammetry using boron-doped diamond and glassy carbon electrodes in aqueous solutions both with and without the addition of surfactant. The compound was irreversibly oxidized in one/two steps at high positive potentials, resulting in the formation of a couple with a reduction and re-oxidation wave at less positive potentials. Special attention was given to the use of adsorptive stripping voltammetry at a surface of mildly oxidized boron-doped diamond electrode in aqueous solutions over the pH range of 1.0–10.0. Addition of anionic surfactant (sodium dodecylsulfate) to ambroxol-containing electrolyte enhanced the stripping current signal. Using square-wave stripping mode, the drug yielded a well-defined voltammetric response in phosphate buffer pH 2.5 containing 4 × 10−4 M sodium dodecylsulfate at +1.02 V (versus Ag/AgCl) (after 30 s accumulation at +0.50 V). The process could be used to determine ambroxol in the concentration range of 0.05–0.7 μM, with a detection limit of 0.010 μM (4.2 ng mL−1). The suggested method was successfully applied to pharmaceuticals and spiked human urine samples.Öğe Synthesis, characterization and experimental, theoretical, electrochemical, antioxidant and antibacterial study of a new Schiff base and its complexes(Elsevier, 2014-09-15) Baykara, Hacı; İlhan, Salih; Levent, Abdulkadir; Seyitoğlu, Mehmet Salih; Özdemir, Sadin; Okumuş, Veysi; Öztomsuk, Abdussamet; Cornejo, MauricioA new Schiff base ligand was synthesized by reaction of salicylaldehyde with 1,6-bis(4-chloro-2-aminophenoxy)hexane. Then the Schiff base complexes were synthesized by metal salts and the Schiff base. The metal to ligand ratio of metal complexes was found to be 1:1. The Cu(II) complex is proposed to be square planar and the Co(II), Ni(II), Mn(II) and Zn(II) complexes are proposed to be tetrahedral geometry. The Ti(III) and V(III) complexes are proposed to be a capped octahedron in which a seventh ligand has been added to triangular face. The complexes are non-electrolytes as shown by their molar conductivities (ΛM). The structure of metal complexes is proposed from elemental analysis, FT-IR, UV–vis, magnetic susceptibility measurements, molar conductivity measurements, Mass Spectra and thermal gravimetric analysis. In addition antimicrobial and antioxidant studies, cyclic voltammetry of the complexes, theoretical 1H NMR and HOMO–LUMO energy calculations of the new di-functional ligand were done.
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