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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 Synthesis, characterization and antioxidant activity of heterocyclic Schiff bases(Journal of the Chinese Chemical Society, 2020-08-04) Aral, Tarık; Dağ, Beşir; Kızılkaya, Hakan; Genç, Nusret; Erenler, RamazanSchiff base derivatives have gained great importance due to revealing a great number of biological properties. Schiff bases were synthesized by treatment of 4-amino-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (1) with various aldehydes in methanol at reflux. In addition, diamine was reacted with an aldehyde to yield the corresponding Schiff bases. The structures of synthesized Schiff bases were elucidated by spectroscopic methods such as microanalysis, 1 H-NMR, 13C-NMR, and FTIR. Antioxidant activities of synthesized Schiff bases were carried out using different antioxidant assays such as 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH• ) scavenging, 2,20 -azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, and reducing power activity. (E)-4-((1H-indol-3-yl)methyleneamino)-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one (3), (E)-1,5-dimethyl-4-((2-methyl-1H-indol-3-yl) methyleneamino)-2-phenyl-1H-pyrazol-3(2H)-one (5), (E)-1,5-dimethyl-2-phenyl-4-(thiophen-2-ylmethyleneamino)-1H-pyrazol-3(2H)-one (7), (E)-1,5-dimethyl2-phenyl-4-(quinolin-2-ylmethyleneamino)-1H-pyrazol-3(2H)-one (9), (1S,2S, N1,N2)-N1,N2-bis((1H-indol-3-yl)methylene)cyclohexane-1,2-diamine (11), and (1S,2S,N1,N2)-N1,N2-bis((2-methyl-1H-indol-3-yl)methylene)cyclohexane-1,2-diamine (12) were synthesized in high yields. Compound 5 displayed a good ABTS•+ activity. Compound 3 revealed the outstanding activity in all assays. Compound 7 has the best-reducing power ability in comparison to other synthesized compounds. Although compounds 5, 11, 12 are new, compounds 3, 7, 9 are known. Due to revealing a good antioxidant activity, the synthesized compounds (3, 5, 7) have the potential to be used as synthetic antioxidant agents.Öğe Plantago major protective effects on antioxidant status after administration of 7,12-dimethylbenz(a)anthracene in rats(Asian Pacific Organization for Cancer Prevention, 2011) Oto, Gökhan; Ekin, Suat; Özdemir, Hülya; Demir, Halit; Yaşar, Semih; Levent, Abdulkadir; Berber, İsmet; Kaki, BarışAim: The present study was designed to evaluate effects of Plantago major extract on oxidative status in Wistar albino rats administrated 7,12-dimethylbenz(a)anthracene (DMBA). Methods: Rats were divided into three equal groups of 6 animals each: Group 1 controls, group 2 treated with DMBA (100 mg/kg, single dose) and group 3 receiving the DMBA and the aqueous extract at 100 mg/kg/d for 60 days. Results: Significant decrease in catalase (P<0.05), carbonic anhydrase (p≤0.01), reduced glutathione (GSH) (P<0.01) and total protein (P<0.01) values was observed in the DMBA group compared with the healthy controls and DMBA + Plantago major groups. Conclusion: The results suggest preventive effects of Plantago major on DMBA induced oxidative damage in Wistar albino rats that might be due to decreased free radical generation.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 Simultaneous electrochemical evaluation of ascorbic acid, epinephrine and uric acid at disposable pencil graphite electrode: Highly sensitive determination in pharmaceuticals and biological liquids by differential pulse voltammetry(Elsevier, 2018) Levent, Abdulkadir; Önal, GünayAim and Objective: As is known, AA, EP and UA can also coexist in biological fluids. Therefore, the determination of the levels of these compounds in biological fluids is extremely important both for the diagnosis and treatment of the related diseases. In the presence of many interfering substances in biological fluids such as blood and urine samples, it is very important that these compounds can be selectively analyzed. Materials and Methods: All electrochemical experiments were performed using an Autolab PGSTAT 128N potentiostat. Before beginning the electrochemical measurements, the PGE was activated. The electrochemical pretreatment of PG was exercised by anodically +1.40 V for 60 s. Then, measurements were performed with CV (-0.4 V to 1.2 V) and DPV (-0.2 V to 0.7 V) for single and simultaneous voltammetric behaviour of AA, EP, and UA in the electrochemical method. Results: The anodic peak potentials of AA and UA were observed at about +0.32 V and +0.62 V, respectively. On the other hand, for EP, while anodic peak potential was observed at about +0.53 V, in the reverse scan, cathodic peak potentials were observed at about +0.41 V and +0.007 V. The39 reduction peak observed at +0.3 V with the oxidation peak observed at +0.53 V are the reversible peaks. In the method developed for the electrochemical simultaneous determination of AA, EP and UA using PGE with DPV technique in BR buffer solution (pH 4.0), the anodic peak potentials are sufficiently separated from each other. Conclusion: A voltammetric method was developed for the simultaneous determination of AA, EP and UA with PGE for the first time. Here, the most important thing is that the simultaneous determination of AA, EP and UA was successfully achieved with that targeted voltammetric method which was sensitive, low-cost, practical and well-repeated; and that these were proven to be selectively applicable in pharmaceutical products and biological liquids.Öğe Novel bis(aminoalcohol)oxalamide organogelators and their diglycolylamide analogs: evaluation of gelation efficiency in various organic fluids(TÜBİTAK, 2017-11-10) Çolak, Mehmet; Pirinççioğlu, Necmettin; Hoşgören, Halil; Barış Cebe, DenizThree modular types of bis(aminoalcohol)oxalamides (1, 4, and 7) and bis(aminoalcohol)diglycolylamide (8) gelators have been prepared by the reaction of the respective aminoalcohols with oxalyl and digycolyl methylesters as potential low-molecular-weight organogelators. The gelation properties of these amides have been evaluated in various aromatic organic solvents (xylene, toluene, isopropyl benzene, and aromatic ether type organic fluids such as anisole or α-phenylethylmethylether) as well as the long-chain aliphatic alcohols (1-hexanol, 1-octanol, 2-octanol, and aromatic 1- phenylethanol). The compounds with sec-butyl and ethyl side chains produce good gelation properties in both aromatic and other organic fluids. Furthermore, the common oxalamide linker present in the gelators was replaced by an extended diglycolylamide linker (8) and its behaviors were compared with the benzylic oxalamide analog (3). The gelator (8) gives the best results with aromatic fluid and lauric acid ethyl ester. 1 H NMR studies reveal the existence of temperaturedependent network assembly/dissolution equilibrium and produce Kgel . FTIR was employed to see the effect of hydrogen bonding in the formation of gel network. Thermodynamic parameters regarding gel-to-sol transition were collected with van’t Hoff relationships.Öğe Separation, optimization, and quantification of cytokinins by a recently developed amide-embedded stationary phase(Taylor & Francis, 2017-07-06) Aral, Hayriye; Haşimi, Duygu; Aral, Tarık; Levent, Abdulkadir; Ziyadanoğulları, BerrinIn this study, some plant growth regulators known as cytokinins [kinetin (K), zeatin (Z), thidiazuron (TDZ), benzylaminopurine (BAP), and dimethylallylaminopurine (AAP)] were separated by HPLC using an amide-embedded mixed-mode stationary phase which was synthesized by Aral et al. in recent years. The effect of mobile phase content, mobile phase pH, buffer concentration, and temperature on separation process was studied. In addition, a quantitative determination of cytokinins from Salvia limbata extract was studied, and some validation parameters such as limit of detection (LOD), limit of quantification (LOQ), and relative standard deviation (RSD) were calculated as a range of 0.03–0.1, 0.1–0.26 mg/L, and 0.03–0.08, respectively.Öğe Chemical constituents and biological activities of cirsium leucopsis, c. sipyleum, and c. eriophorum(Walter de Gruyter, 2015-03-19) Boğa, Mehmet; Köseoğlu Yılmaz, Pelin; Barış Cebe, Deniz; Fatima, Mashhad; Siddiqui, Bina S.; Kolak, UfukTwo endemicCirsiumspecies,C. leucopsisDC. andC. sipyleumO. Schwarz, andC. eriophorum(L.) Scop. growing in Turkey were investigated to establish their secondary metabolites, fatty acidcompositions, and antioxidant and anticholinesterase potentials. Spectroscopic methods were usedto elucidate the structures of thirteen known compounds (p-hydroxy-benzoic acid, vanillic acid,cis-epoxyconiferyl alcohol, syringin, balanophonin, 1′-O-methyl-balanophonin, apigenin, kaempferol-3-O-β-D-glucopyranoside, kaempferol-3-O-α-L-rhamnopyranoside, taraxasterol, taraxasterol acetate,β-sitosterol,β-sitosterol-3-O-β-D-glucopyranoside).cis-Epoxyconiferyl alcohol and 1′-O-methyl-balanophonin were isolated for the first time fromCirsiumspecies. Palmitic acid (47.1 %) was foundto be the main fatty acid ofC. leucopsis, linoleic acid in bothC. sipyleum(42.1 %) andC. eriophorum(37.8 %). Assays ofβ-carotene bleaching, scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) freeradicals, 2,2-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium (ABTS) cation radicals,and superoxide anion radicals, as well as cupric reducing antioxidant capacity (CUPRAC) were usedto determine the antioxidant activities of the extracts and isolated compounds. Vanillic acid, balano-phonin, and kaempferol-3-O-α-L-rhamnopyranoside exhibited strong antioxidant activity. Taraxa-sterol was a potent inhibitor of acetyl- and butyrylcholinesterase activity, respectively.Öğe Enantioselevtive compexation of chiral lariat crown ethers and chiral primary alkylamonum perchlorates(Turkish Journal Chemistry, 2011-02-01) Aral, Tarık; Köylü, Mehmet Zafer; Kocakaya, Şafak Özhan; Karakaplan, Mehmet; Hoşgören, HalilIn order to investigate the enantiomeric recognition abilities toward 2 chiral alkylammonium perchlorates (AmI, AmII) by 1 H-NMR titration method in CDCl 3, 4 chiral lariat ethers 8-11 with a (p-methoxyphenoxy) methyl flexible side arm were used. The most effective enantiomeric recognition was obtained by LCEs 9 and 11 toward AmII, by KR /KS 6.58 and KS /KR 6.63, respectively. The effect of macroring size, subunit of macroring, and side arm appeared to have strong influence on the binding ability of these alkylammonium ions.
