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    Adsorption of Remazol Brilliant Blue R using ZnO fine powder: Equilibrium, kinetic and thermodynamic modeling studies
    (Elsevier, 2009) Ada, Kezban; Ergene, Aysun; Tan, Sema; Yalçın, Emine
    Zinc oxide powders with six-sided flake-like particles were prepared by homogeneous precipitation from boiling aqueous solutions that contained excess urea and 0.075 (Z075) and 0.300 (Z300) M Zn2+. The average sizes of the particles are 37 and 46 mu m, while the average sizes of the crystals are similar to 45 for Z075 and Z300 at 1000 degrees C. Equilibrium, kinetic and thermodynamic studies were carried out for the adsorption of RBBR dye from aqueous solution using both types of ZnO in the form of fine powders. The effects of pH, initial dye concentration, contact time and temperature of solution on the adsorption were studied. Langmuir, Temkin and Dubinin-Radushkevich (D-R) isotherm models were used to describe the adsorption of RBBR onto ZnO powders. The Langmuir and D-R isotherm models fit the equilibrium data better than the Temkin isotherm model. The monomolecular adsorption capacity of Z075 and Z300 was determined to be 190 and 345 mg g(-1) for RBBR, respectively. The Lagergren first-order, Ritchie second-order kinetic and intra-particle diffusion models were used for the adsorption of the dye onto ZnO powders. The Ritchie second-order model was suitable for describing the adsorption kinetics for the removal of RBBR front aqueous solution onto Z075 and Z300. Thermodynamic parameters, such as the Gibbs free energy (Delta G(#)), enthalpy (Delta H-#), entropy (Delta S-#) and equilibrium constant of activation (K-#) were calculated. These parameters showed that the adsorption process of RBBR onto Z075 and Z300 was an endothermic process of a chemical nature under the studied conditions. (C) 2008 Elsevier B.V. All rights reserved.
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    Antibacterial and antifungal activity of Heracleum sphondylium subsp artvinense
    (Academic Journals, 2006) Ergene, Aysun; Güler, Perihan; Tan, Stewart; Mirici, Semra; Hamzaoğlu, Engin; Duran, Ahmet
    Ethanol and aqueous extract of Heracleum sphondylium subsp. artvinense was investigated for their antimicrobial activities against eight bacterial species (Enterococcus feacalis, Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes, Shigella, Streptococcus pyogenes, and Corynobacterium diphtheria) and two yeast (Candida albicans and C. krusei). Both ethanol and aqueous extract of H. sphondylium subsp. artvinense showed antimicrobial activity against the gram-positive bacterium (S. aureus).
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    Antimicrobial activity of 4-subtituted-styrl-2-azetindinones
    (2005) Tan, Sema; Güner, Adar Vildan; Ergene, Aysun
    Bu çalışmada, daha önceden sentezleri yapılan 1-(substitutefenil)-4-(substiiuestril)-2-azetidinonlarin (3a-i) antimikrobiyal aktiviteleri incelenmiştir. Bütün bileşikler Gram () ve Gram (-) bakterilere ve mayaya karşı test edilmiştir. Aktivite, halkadaki substituentlerden önemli derecede etkilenmediği bulundu
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    Antimicrobial activity of 4-subtituted-styrl-2-azetindinones
    (Turkish Pharmacists Assoc, 2005) Tan, Sema; Güner, Vildan Adar; Ergene, Aysun
    In this study, antimicrobial activity of previously synthesized 1-(Substituted phenyl)-4-(substituted styryl)-2-azetidinones(3a-i) have been examined. All compounds have been tested against Gram(+) and Gram(-) bacteria and yeasts. It was found that activity is not significantly influenced by the substituents on the ring.
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    Antimicrobial Activity of Heracleum antasiaticum
    (Int Soc Horticultural Science, 2009) Ergene, Aysun; Tan, Sema; Mirici, Semra; Güler, P.; Yildirim, S.
    Heracleum L. (Apiaceae) includes more than 70 species in the world. This variety is representing 17 species in Turkey of which 7 species are endemic. Heracleum antasiaticum is an endemic species for Turkey. Heracleum antasiaticum has been shown to possess medicinal value, in particular, and antimicrobial activity. Heracleum antasiaticum was assayed for their in vitro antibacterial activities against eight pathogenic bacteria, and three yeast spp. The antimicrobial activity of the ethanol extract and water extract of Heracleum antasiaticum was investigated using an agar diffusion method. Ethanolic and aqueous extract of Heracleum antasiaticum differed significantly in their activity against the test microorganisms.
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    Biobleaching of kraft cellulose pulp by Poliporus versicolor
    (Elsevier Science Bv, 2005) Ergene, Aysun; Kolankaya, N.
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    Biobleaching of kraft cellulose pulp by Poliporus versicolor
    (Elsevier Science Bv, 2005) Ergene, Aysun; Kolankaya, N
    [Abstract No tAvailable]
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    Biochemical and Molecular Characterization of Strontium-resistant Environmental Isolates of Pseudomonas fluorescens and Sphingomonas paucimobilis
    (Taylor & Francis Inc, 2013) Özer, Gamze; Ergene, Aysun; İçgen, Bülent
    Strontium resistance was investigated in strains isolated from the river Kzlrmak which has been affected by industrial and agricultural heavy metal pollution from the surrounding facilities and domestic effluents from the city Krkkale, Turkey. Strontium-resistant isolates with a minimal inhibitory concentration of 2000mg L-1 were isolated and identified as Pseudomonas fluorescens and Sphingomonas paucimobilis. Both isolates were shown to be resistant to other heavy metals like aluminum, lithium, barium, nickel and resistance to the antibiotics like aztreonam and pefloxacin. Plasmid DNA analysis, transformation and curing results revealed that the strontium resistance ability of both isolates was chromosome-encoded. Outer membrane and total protein isolation results descriptively showed that not only membrane porins but also other proteins were effective in the strontium resistance in Pseudomonas fluorescens and Sphingomonas paucimobilis.
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    Biosorption of reactive dyes on Scenedesmus obliquus
    (Elsevier Science Bv, 2005) Tan, S.; Katircioğlu, Hikmet; Öktem, Zeki; Ergene, Aysun
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    Centaurea mersinensis phytochemical composition and multi-dimensional bioactivity properties supported by molecular modeling
    (Taylor and Francis Ltd., 2024) Yırtıcı, Ümit; Ergene, Aysun; Adem, Şevki; Atalar, Mehmet Nuri; Eyüpoğlu, Volkan; Rawat, Ravi; Arat, Esra
    Various studies conducted on Centaurea species indicate that the relevant plant is good source of bioactive phytochemicals. In this study, in vitro studies were used to determine bioactivity properties of methanol extract of Centaurea mersinensis - endemic species in Turkey - on extensive basis. Furthermore, the interaction of target molecules, identified for breast cancer and phytochemicals in the extract, was investigated via in silico analyses to support findings received in vitro. Scutellarin, quercimeritrin, chlorogenic acid and baicalin were primary phytochemicals in the extract. Methanol extract and scutellarin had higher cytotoxic effects against MCF-7 (IC50=22.17 µg/mL, and IC50=8.25 µM, respectively), compared to other breast cancer cell lines (MDA-MB-231, SKBR-3). The extract had strong antioxidant properties and inhibited target enzymes, especially ?-amylase (371.69 mg AKE/g extract). The results of molecular docking indicate that main compounds of extract show high-strength bonding to the c-Kit tyrosine among target molecules identified in breast cancer, compared to other target molecules (MMP-2, MMP-9, VEGFR2 kinase, Aurora-A kinase, HER2). The tyrosinase kinase (1T46)-Scutellarin complex showed considerable stability in 150 ns simulation as per MD findings, and it was coherent with optimal docking findings. Docking findings and HOMO-LUMO analysis results corresponds with in vitro experiments. Medicinal properties of phytochemicals, which was determined to be suitable for oral use along with ADMET, were found to be within normal limits except for their polarity properties. In conclusion, in vitro and in silico studies indicated that the relevant plant yields promising results regarding its potential to develop novel and effective medicational products. Communicated by Ramaswamy H. Sarma. © 2023 Informa UK Limited, trading as Taylor & Francis Group.
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    Centaurea mersinensis phytochemical composition and multi-dimensional bioactivity properties supported by molecular modeling
    (Taylor & Francis Inc, 2024) Yirtici, Umit; Ergene, Aysun; Adem, Sevki; Atalar, Mehmet Nuri; Eyupoglu, Volkan; Rawat, Ravi; Arat, Esra
    Various studies conducted on Centaurea species indicate that the relevant plant is good source of bioactive phytochemicals. In this study, in vitro studies were used to determine bioactivity properties of methanol extract of Centaurea mersinensis - endemic species in Turkey - on extensive basis. Furthermore, the interaction of target molecules, identified for breast cancer and phytochemicals in the extract, was investigated via in silico analyses to support findings received in vitro. Scutellarin, quercimeritrin, chlorogenic acid and baicalin were primary phytochemicals in the extract. Methanol extract and scutellarin had higher cytotoxic effects against MCF-7 (IC50=22.17 mu g/mL, and IC50=8.25 mu M, respectively), compared to other breast cancer cell lines (MDA-MB-231, SKBR-3). The extract had strong antioxidant properties and inhibited target enzymes, especially alpha-amylase (371.69 mg AKE/g extract). The results of molecular docking indicate that main compounds of extract show high-strength bonding to the c-Kit tyrosine among target molecules identified in breast cancer, compared to other target molecules (MMP-2, MMP-9, VEGFR2 kinase, Aurora-A kinase, HER2). The tyrosinase kinase (1T46)-Scutellarin complex showed considerable stability in 150 ns simulation as per MD findings, and it was coherent with optimal docking findings. Docking findings and HOMO-LUMO analysis results corresponds with in vitro experiments. Medicinal properties of phytochemicals, which was determined to be suitable for oral use along with ADMET, were found to be within normal limits except for their polarity properties. In conclusion, in vitro and in silico studies indicated that the relevant plant yields promising results regarding its potential to develop novel and effective medicational products.Communicated by Ramaswamy H. Sarma
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    Cytogenetic damage in Allium cepa root meristems induced by Dursban 4 and Antracol WP 7 pesticides
    (Elsevier Science Bv, 2009) Ergene, Aysun; Tan, Sema; Yılmaz, F.; Topçu, Selim; Kaya, A.; Arslanoğlu, İlhan; Yalçın, E.
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    Cytotoxic and apoptotic effects of endemic Centaurea fenzlii Reichardt on the MCF-7 breast cancer cell line
    (Tubitak Scientific & Technical Research Council Turkey, 2017) Yirtici, Umit; Goger, Fatih; Sarimahmut, Mehmet; Ergene, Aysun
    The main purpose of this study was to analyze the cytotoxic activity of an extract obtained from Centaurea fenzlii Reichardt, and the fractions eluted from this extract, in breast cancer cells. After isolation and structural analysis of the fractions were conducted, a meaningful cytotoxic effect was indicated. The goal of the analysis was to reveal the mechanism by which this effect occurs through researching the apoptotic side of these fractions and determining the amount of several proteins that are the products of the genes. Test substances were applied to breast cancer cells and the inhibitory concentration value 50 (IC50) that caused a cytotoxic effect was determined using MTT and ATP assays. The Centaurea fenzlii Reichardt dichloromethane extracts-ethyl acetate fractions (CFDCM-EAF) exhibited a stronger growth-inhibitory effect on MCF-7 cells (45.771 mu g/mL). The apoptotic effect was studied using double staining and flow cytometry. The death rate in the cells treated with the CFDCM-EAF IC50 dose was approximately 90%: 9.2% living cells, 22.8% necrotic cells, 62.3% late apoptotic cells, and 5.8% early apoptotic cells. Structural analysis of the CFDCM-EAF, which indicated significant cytotoxic effects, was performed using chromatographic methods. Hispidulin was the major component of the CFDCM-EAF by LC-APCI-MS/MS analysis.
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    The cytotoxic effect of endemic Centaurea fenzlii Reichardt on colon cancer cell lines
    (Georg Thieme Verlag Kg, 2012) Yırtıcı, Ümit; Yilmaz, F.; Serim, Gamze; Kirimer, Neşe; Ulukaya, Engin; İçgen, Bülent; Ergene, Aysun
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    Cytotoxic effects of lead and mercury ions on root tip cells of Cicer arietinum L
    (Parlar Scientific Publications (P S P), 2009) Çavuşoğlu, Kültigin; Ergene, Aysun; Yalçın, Emine; Tan, Sema; Çavuşoğlu, Kürşat; Yapar, Kürşad
    In the present study, the cytotoxic effects of different concentrations of lead (Pb) and mercury (Hg) ions on Cicer arietinum L. root tip cells were investigated. For this aim, we used the aermination percentage, root length, weight gain, mitotic index (MI), the frequency of micronucleus (MN) and chromosomal aberrations (CAs) as indicators of cytotoxicity, and correlated these data with statistical parameters. Additionally to the cytogenetic analysis, lipid peroxidation and DNA analyses were performed in root tip meristems of C. arietinum treated with Hg and Pb. The seeds were divided into 5 groups as control, Hg and Pb treatment groups. They were treated with 10 and 50 ppm doses of Hg and Pb during 7 consecutive days. The initial and final weights of all the seeds were measured by sensitive balance to determine the effects of Pb and Hg on the weight gain. As a result, there was a significant alteration in germination percentage, root length, weight gain, MI, MN and CAs frequency depending on treatment dose in the seeds exposed to Hg and Pb when compared with the controls. Heavy metal exposure significantly reduced the germination percentage, root lenght and weight gain in all the treatment groups. But, it caused an increase in the MN and CAs formation. Pb and Hg metals caused various types of CAs at a rate which increased systematically with increased levels of Pb and Hg. It was also found that Pb and Hg metals have a mitodepressive action on mitosis, and the MI was decreased depending on the dose of Pb and Hg applied. Besides, 10 and 50 ppm concentrations of Pb and Hg significantly enhanced the lipid peroxidation and caused an increase in malondialdehyde (MDA) levels at both doses. The investigated parameters (except MDA, MN and CAs frequency) were higher in the seeds exposed to Pb than those treated with Hg. In other words, Hg had much more toxic effect on plant tissues than Pb. Moreover, it was observed that the yields of DNA in the seeds treated with Pb and Hg were lower than in the controls. Hence, DNA yields exposed to Pb and Hg were run ahead on agarose gel according to the control group. The results clearly indicate that Hg and Pb have important cytotoxic effects on the root tip cells, and C arietinum seeds are very sensitive and useful as biomarker for monitoring of these effects.
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    The cytotoxic, biochemical and physiological effects of Basudin 60 EM and Cupravit ob 21 pesticides on Allium cepa
    (Elsevier Science Bv, 2009) Tan, Sema; Ergene, Aysun; Topçu, Selim; Yılmaz, Funda; Kaya, A.; Arslanoğlu, İlhan; Cavuşoğlu, Kültiğin
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    Determination of MIC and MBC Values Using Different Extraction Methods in Plants of Nigella Sativa, Cuminum Cyminum and Pimpinella Anisum L. Samples from Kırıkkale Region
    (2023) Böke, Eftal; Kaçmaz, Birgül; Ergene, Aysun
    In our study, it was aimed to investigate the antimicrobial effect of 6 plant extracts obtained with methanol by using maceration and soxlet methods from 3 plant species Nigellla sativa (Black seed), Cuminum cuminum (cumin) and Pimpinella anisum (anise) grown in Kırıkkale province by liquid microdilution method against Staphylococcus aureus (ATCC 25923) and Escherichia coli (ATCC 25922). All of the extracts of Nigellla sativa (black cumin), Cuminum cuminum (Cuminum) and Pimpinella anisum (Anise) prepared by the maceration and soxalet method showed antibacterial effects against both bacteria (inhibitory and bactericidal). it was determined that the antibacterial effect of the extracts obtained by the maceration method was higher than the extracts obtained by the soxalet method.
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    Endemik centaurea fenzlii reichardt türünün kolon ve meme kanseri hücre dizileri üzerindeki sitotoksik ve apoptotik etkisi
    (2013) Ergene, Aysun; Kırımer, Neşe; İçgen, Bülent; Yırtıcı, Ümit
    [Abstract Not Available]