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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 Asymmetric organocatalytic efficiency of synthesized chiral β-amino alcohols in ring-opening of glycidol with phenols(Springer Nature, 2012-04-11) Aral, Tarık; Karakaplan, Mehmet; Hoşgören, HalilA series of novel chiral β-amino alcohols 3-5 and 7-10 were synthesized by regioselective ring opening of epoxides and chiral amines with a straightforward method in high yields (up to 99 %). Kinetic resolution of racemic glycidol with phenols was achieved by using chiral amino alcohols as organocatalysts. Amino alcohols 5, 8 and 10 exhibited the highest enantioselectivities with p-cresol, phenol, and p-methoxyphenol by 63, 65, 58 % ee, respectively. The moderate enantioselectivities were observed with catalyst 9b towards all the nucleophiles (34-48 % ee). The ee values of the desired 3-aryloxy-1, 2-diols were determined by HPLC. This study presents an attractive tool for the synthesis of β-blockers and structurally complex molecules.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 Kiral amitdiol jelatörler(Kimyagerler Derneği, 2011) Barış Cebe, Deniz; Şeker, Sevil; Aydın, Haluk; Toğrul, Mahmut; Çolak, Mehmet; Hoşgören, HalilKüçük molekül kütleli organik bile iklerin gösterdi i jelle me, son zamanlarda oldukça ilgi çekmektedir. Yeni yumu ak malzeme olan jellerin ilacn yava da tlmas, iç veya d uyarcya (pH, scaklk, k, çözünen) yant veren sistemlerin dizayn; sv atk (petrol, ya gibi) ve toksik boyar maddelerin uzakla trlmas gibi uygulama alanlar vardr [1]. Ayrca tehlikeli svlarn güvenle ta nmas ve bölmeli reaksiyon veya kristallendirme kaplar olarak da kullanlabilirler [2]. Jelle me olaynn supramoleküler do as yeterince anla lmamasna kar n, genellikle mikrometre uzunlu unda ve nanometre çapnda olan jel elyaflar jelatör moleküllerinin tek yönlü ve kendili inden toplanmas sonucu olu ur. Nanometre boyutundaki bu elyaflarn birbiriyle nonkovalent (Hidrojen ba , |-| steacing, Van-der walls) etkile imler sonucu olu an ebeke (network) bölmelerinde çözücünün hapsedilmesi sonucu olu ur. A rlkça %0.05’den daha dü ük deri imlerde bile jelle ebilen çok sayda ve oldukça etkin süper jelatörler hazrlanm tr [3]. Bu çal mada kiral amitdioller sentezlenip çe itli çözücülerle jel olu turabilme özellikleri incelenmi tir. Jelatör olarak ekil 1’de yaplar verilen moleküller kullanld. Çözücü olarak toluen, ksilen, anisol, benzen gibi aromatik bazl çözücüler yannda asetonitril, etil alkol, dioksan, CHCl3, CH2Cl2 gibi çözücüler yannda n-hegzan ve CCl4 gibi apolar çözücüler ve bunlarn kar mlar denendi. Genel olarak II yaps denenen çözücülerde jelle me vermezken; en iyi jelle menin I yapsnn R grubu Sec-Bütil oldu u durumda elde edilmi tir. Elde edilen jellerin morfolojisi ve fizikokimyasal parametreleri ileride çal lacaktr.Öğe Düşük mol kütleli homo kiral bis amino alkol okzal amit jelatörler(Muğla Sıtkı Koçman Üniversitesi, 2012) Barış Cebe, Deniz; Kaya, Gülşen; Kaplan, Şeref; Çolak, Mehmet; Aydın, Haluk; Hoşgören, HalilÖğe Determination of Cu contamination in some spring and mineral waters around van by AAS after enrichment of activated carbon(Medwell, 2011) Dağ, Beşir; Kılıçel, FevziSome trace metal contamination in water is a major component in the determination of water quality. In order to supply qualify water for health of human being, terrestiral and aquatic animals is very important. Apparently, tap water and spring water qualities in many countries are effected by industrilization and over population. The main aim of this study was to detect copper metal concentration in some spring and mineral water around Van by means of Atomic Absorption Spectrometer after enrichment of activated carbon. Spring and mineral water samples were collected some different parts of city. These mineral and spring water samples were determined by a simple preconcentration method which is called activated carbon enrichment. The metal analysis was done to detect copper element. It was compared the results with standarts for drinking water quality of World Health Organization (WHO) and Europian Union drinking water standarts. As a result, copper level in the spring and mineral water around Van were generally suitable for the both criterias of World Health Organization (WHO) and Europian Union drinking water.Öğe Electrochemical determination of melatonin hormone using a boron-doped diamond electrode(Elsevier, 2012-01) Levent, AbdulkadirIn this study, a boron-doped diamond electrode was used for the electroanalytical determination of melatonin in the pharmaceutical tablet and urine samples by square-wave voltammetry. Melatonin yielded a well-defined voltammetric response in Britton-Robinson buffer, pH 3.0 at + 0.88 V (vs. Ag/AgCl). Using the optimal square-wave voltammetry conditions, the oxidation peak was used to determine melatonin in the concentration range of 5.0 × 107 M to 4.0 × 106 M (r = 0.998, n = 8), a detection limit of 1.1 × 107 M (0.025 μg/mL) and relative standard deviation was 2.06% at the 2.0 × 106 M level (n = 10). Recoveries of melatonin were in the range of 97.67–105%, for both tablet and spiked human urine samples.Öğe In vitro antimicrobial and antioxidant activity of ethanol extract of three hypericum and three achillea species from Turkey(Taylor & Francis, 2011-02-25) Barış Cebe, Deniz; Kızıl, Murat; Aytekin, Mehmet Çetin; Kızıl, Göksel; Yavuz, Murat; Çeken Toptancı, Bircan; Ertekin, Alaattin SelçukThe present study was conducted to determine the antimicrobial, antifungal and antioxidant activity of the ethanol extract of Hypericum scabrum L (HSm), Hypericum lysimachioides var. lysimachioides (HL), and Hypericum retusum Aucher (HR) and ethanol extracts of Achillea aleppica D.C. subsp. aleppica (AA), Achillea aleppica D.C. subsp. zederbaueri (Hayek) Hub.-Mor (AZ), and Achillea biebersteinii Afan. (AB). The antioxidant properties of extracts were evaluated using different antioxidants tests, including reducing power, free radical scavenging, deoxyribose assay, metal chelating activities and determination of total phenolic compounds. The extracts obtained from Hypericum and Achillea species showed high antioxidant properties. The protective effects of plant extracts were compared with a well known antioxidant, Butilated Hydroxytoluen (BHT) and α-tocopherol. Total antioxidant activity of ethanol extracts of plants were also tested by using ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods. Antioxidative activities of plant extracts were found to be comparable with Vitamin E. The results showed that the ethanol extracts of all tested plant exhibited different activity against tested microorganisms. Since most of the studied extracts have good antimicrobial and antioxidant activity, it might be possible to use them as natural food additives that act both as antioxidants and as spices.Öğe Novel C2-symmetric macrocycles bearing diamide-diester groups: Synthesis and enantiomeric recognition for primary alkyl ammonium salts(American Chemical Society, 2008-03-12) Sünkür, Murat; Barış Cebe, Deniz; Hoşgören, Halil; Toğrul, MahmutWe synthesized a series of novel macrocycles with diamide−diester groups (S,S)-1, (S,S)-2, (S,S)-3, and (R,R)-1, derived from dimethyloxalate and amino alcohols by high dilution technique, and evaluated enantiomeric recognition properties of these macrocycles toward primary alkyl ammonium salts by 1H NMR titration. Taking into account the host employed, important differences were observed in the Ka values of (R)-Am and (S)-Am for (S,S)-1 and (R,R)-1 hosts, KS/KR = 5.55 and KR/KS = 3.65, ΔΔGo = 0.43 and −0.32 kJ mol-1, respectively. There seems a general tendency for the host to include the guests with the same absolute configuration.Öğe Yeni bir amid silika dolgu maddesinin sentezi ve hidrofilik etkileşim sıvı kromatografisi (HILIC) uygulamaları(Mustafa Kemal Üniversitesi, 2012-09) Aral, Tarık; Aral, Hayriye; Ziyadanoğulları, Berrin; Ziyadanoğulları, Recep
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