Sürdürülebilir Kalkınma Amaçları

Yazarlar

  • MakaleYalnız künye2017Scopus SJRQ1
    Purification of camel liver catalase by zinc chelate affinity chromatography and pH gradient elution: An enzyme with interesting properties

    Chafik, Abdelbasset; Essamadi, Abdelkhalid; Çelik, Safinur Yildirim; Mavi, Ahmet

    Climate change and increasing temperatures are global concerns. Camel (Camelus dromedarius) lives most of its life under high environmental stress in the desert and represent ideal model for studying desert adaptation among mammals. Catalase plays a key role in protecting cells against oxidative stress. For the first time, catalase from camel liver was purified to homogeneity by zinc chelate affinity chromatography using pH gradient elution, a better separation was obtained. A purification fold of 201.81 with 1.17% yield and a high specific activity of 1132539.37 U/mg were obtained. The native enzyme had a molecular weight of 268 kDa and was composed of four subunits of equal size (65 kDa). The enzyme showed optimal activity at a temperature of 45 °C and pH 7.2. Thiol reagents, β-Mercaptoethanol and D,L-Dithiothreitol, inhibited the enzyme activity. The enzyme was inhibited by Al3+, Cd2+ and Mg2+, whereas Ca2+, Co2+ and Ni2+ stimulated the catalase activity. Reduced glutathione has no effect on catalase activity. The Km and Vmax of the enzyme for hydrogen peroxide were 37.31 mM and 6185157 U/mg, respectively. Sodium azide inhibited the enzyme noncompetitively with Ki value of 14.43 μM, the IC50 was found to be 16.71 μM. The properties of camel catalase were different comparing to those of mammalian species. Relatively higher molecular weight, higher optimum temperature, protection of reduced glutathione from hydrogen peroxide oxidation and higher affinity for hydrogen peroxide and sodium azide, these could be explained by the fact that camel is able to live in the intense environmental stress in the desert.

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  • MakaleAçık Erişim2017Scopus SJRQ3
    The antioxidant activity, vitamin c contents, physical, chemical and sensory properties of ice cream supplemented with cornelian cherry (Cornus mas L.) paste; [Kızılcık (Cornus mas L.) ezmesi ılaveli dondurmanın antioksidan aktivitesi, C Vitamini ıçeriği, fiziksel, kimyasal ve duyusal özellikleri]

    Topdaş, Elif Feyza; Çakmakçi, Songül; Çakiroğlu, Kübra

    The aim of this research was to investigate the effect of cornelian cherry (Cornus mas L.) paste (CP) on the quality properties of ice cream. CP was added to an ice cream mix at four concentrations (0, 5, 10 and 15%, w/w) for ice cream production. The increment of CP level caused the increased of vitamin C content, a values and overrun values, whereas it decreased the viscosity of samples compared to Control ice cream sample. The results indicated that lyophilised water extracts of CP (LWECP) contain remarkable phenolic compounds. The findings showed that there is a positive correlation between the total phenolics and flavonoid contents in LWECP and ice cream samples antioxidant activity. CP has shown to be an effective source of natural antioxidants. CP may be used as a source of natural colour and flavour agent in ice cream manufacture. CP enhanced vitamin C amounts of ice cream, and improve sensory properties. In the literature surveys of Science Direct, Web of Science, Google Scholar and Scopus databases an ice cream study using cornelian cherry fruit was not found.

    • SDG 2 · Açlığa Son
    • SDG 3 · Sağlık ve Kaliteli Yaşam
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  • MakaleAçık Erişim2017Scopus SJRQ1
    Improvement in levitation force performance of bulk MgB2 superconductors through coronene powder adding

    Erdem, O.; Abdioglu, M.; Guner, S.B.; Celik, S.; Kucukomeroglu, T.

    The effect of coronene (C24H12) addition on the levitation force properties of MgB2 superconductor has been investigated for the first time in this study. The polycrystalline disk-shaped MgB2 + y wt % C24H12 samples (y = 0, 2, 4, 6, 8, 10), were synthesized by a pellet/closed tube method at 850 °C under Ar atmosphere, after hot pressing at 200 °C. XRD analysis indicates a decrease in lattice parameters of coronene added samples and confirms substitution of carbon in boron sites. An increase in lattice strain and a decrease in grain size are observed due to the carbon substitution effect. Vertical and lateral levitation force measurements under zero-field-cooled and field-cooled regimes were carried out at different temperatures of 20, 25 and 30 K. It was found that the coronene addition significantly increases the high-field critical current density of MgB2. The Jc values were obtained as 4.6 × 103 Acm−2 and 1.3 × 104 Acm−2 for pure and 4 wt % coronene added samples at 20 K and 4 T. In addition, the levitation force measurements show that 4 wt % coronene adding is very effective in increasing both the vertical and lateral levitation force performances at 20 K. The maximum levitation force for 4 wt % coronene added sample corresponds to 7.58 N/g whereas the reference sample shows 6.73 N/g at 20 K in ZFC regime. The results point out that the hydrocarbon of C24H12 is an effective carbon-containing additive for MgB2 and can be useful for optimizing the levitation performance of MgB2 superconductors for potential applications.

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  • MakaleAçık Erişim2017Scopus SJRQ2
    Highly Enantioselective Production of Chiral Secondary Alcohols with Candida zeylanoides as a New Whole Cell Biocatalyst

    Şahin, Engin; Dertli, Enes

    The increasing demand for biocatalysts in synthesizing enantiomerically pure chiral alcohols results from the outstanding characteristics of biocatalysts in reaction, economic, and ecological issues. Herein, fifteen yeast strains belonging to three food originated yeast species Candida zeylanoides, Pichia fermentans, and Saccharomyces uvarum were tested for their capability for asymmetric reduction of acetophenone to 1-phenylethanol as biocatalysts. Of these strains, C. zeylanoides P1 showed an effective asymmetric reduction ability. Under optimized conditions, substituted acetophenones were converted to corresponding optically active secondary alcohols in up to 99% enantiomeric excess and at high yields. The preparative scale asymmetric bioreduction of 4-nitroacetophenone (1m) by C. zeylanoides P1 gave (S)-1-(4-nitrophenyl)ethanol (2m) with 89% yield and > 99% enantiomeric excess. Compound 2m has been obtained in an enantiomerically pure and inexpensive form. Additionally, these results indicate that C. zeylanoides P1 is a promising biocatalyst for the synthesis of chiral alcohols in industry.

    AtıfScopus32WoS30
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  • MakaleYalnız künye2017Scopus SJRQ2
    Mechanism of capsaicin inhibition of aldose reductase activity

    Alim, Zuhal; Kilinc, Namık; Sengul, Bulent; Beydemir, Sukru

    Aldose reductase (AR) inhibitors play a vital importance as a potential therapeutic and preventive medicine when it comes to hyperglycemia associated diabetic complications. Additionally, capsaicin is used as a food additive and a drug in a number of diverse clinical trials. The aim of this study is to determine the in vitro inhibition behavior of capsaicin on AR enzyme activity, which was obtained from different rat tissues (heart, kidney, liver, and brain). We showed that AR was inhibited by capsaicin in the micromolar range and noncompetitive manner in all of the tissues. Ki values of capsaicin were found to be 8.87, 264, 535, and 597, respectively, in heart AR, kidney AR, liver AR, and brain AR. In conclusion, capsaicin may be an effective molecule when used in low concentrations to prevent diabetic complications associated with the polyol pathway.

    • SDG 3 · Sağlık ve Kaliteli Yaşam
    AtıfScopus21WoS19OpenAlex24
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  • MakaleAçık Erişim2017Scopus SJRQ2
    A new method for titania thin film production: Thermionic vacuum arc method

    Şenay, Volkan; Özen, Soner; Pat, Suat; Geçici, Birol; Korkmaz, Şadan

    In this research, transparent titania (TiO2) thin films were deposited on a glass microscope slide and on a flexible polyethylene terephthalate (PET) substrate under a high vacuum condition by means of the thermionic vacuum arc (TVA) method in a very short period of time (60 s). Optical properties and surface properties of the coated TiO2 surfaces are related to the structural changes of the coated layers due to ion energies and substrate effect. But obtained results are closely linked to literature values. Our analysis showed that the TVA method is an alternative method for low-temperature coatings and the produced films present important advantages for optical and industrial applications.

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  • MakaleAçık Erişim2017Scopus SJRQ2
    Edible packaging film derived from mechanically deboned chicken meat proteins: Effect of transglutaminase on physicochemical properties

    Yayli, Damla; Turhan, Sadettin; Saricaoglu, Furkan Turker

    In this study, effect of transglutaminase (TGase) addition on physical, water barrier, optical and mechanical properties of mechanically deboned chicken meat protein (MDCM-P) films was investigated. When TGase was added to the films, the thickness increased, but the solubility decreased. Films treated with TGase exhibited higher water vapor permeability than control film (p<0.05). When TGase concentration increased, the L∗ values of films decreased, but a∗ and b∗ values increased. All films showed very good barrier properties against UV light. The highest tensile strength was obtained in MDCM-P films containing 3% TGase (p<0.05). The elongation at break values increased with the TGase concentration increasing from 1 to 3%, but decreased at higher enzyme concentration (p<0.05). The addition of TGase altered molecular organization and intermolecular interaction in the film matrix. TGase treated films showed smoother and ordered surface structure and homogeneous and compact microstructure. The results indicated that TGase use can be an effective approach in improving the solubility and mechanical properties of MDCM-P films.

    • SDG 2 · Açlığa Son
    AtıfScopus28WoS25OpenAlex33
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  • MakaleYalnız künye2017Scopus SJRQ4
    Structural investigation, drug likeness scoring and structure activity/property relationships applied on 1,2,3-thiadiazole derivatives, with kinase inhibitors activity

    Oukil, Oualid; Tchouar, Noureddine; Belaidi, Salah; Salah, Toufik; Cinar, Mehmet

    All calculations and the equilibrium geometries of 1,2,3-thiadiazole have been performed using ab initio/HF, MP2 and DFT methods with different basis sets. The molecular electrostatic potential surface (MESP) that reveals centers of reactivity of the molecule and substitution effects of the molecular system have been studied using the HSAB principle (Hard Soft Acid and Base). Also, the multi-parameter optimization (MPO) methods and structure activity/property relationship studies were carried out on twenty-one molecules of 1,2,3-thiadiazole derivatives which are potent VEGFR-2/KDR kinase inhibitors. In the present work results such as net charges, bond lengths, dipole moments, QSAR properties, Lipinski’s parameters, Lipophilic Efficiency (LipE), have been calculated and discussed. (Figure Presented).

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  • MakaleAçık Erişim2017Scopus SJRQ2
    Effect of XRD relative intensities of the Li (002) on surface, optical and electrochemical impedance spectroscopy analyses of the deposited LiCoO2 thin film

    Yudar, H. Hakan; Pat, Suat; Özen, Soner; Şenay, Volkan; Korkmaz, Şadan; Pat, Zerrin

    In this paper, the effect of RF power on LiCoO2 thin films was investigated using X-ray diffractometer (XRD), atomic force microscopy, UV–Vis spectrophotometer, and potentiostat. The microstructural, surface, optical and electrochemical impedance measurements were performed to LiCoO2 thin films, are used to for the fully solid-state battery cathode material. According to obtained results, the relative intensities of the Li (002) crystal phase in XRD patterns of deposited LiCoO2 thin films were increased by increasing applied RF power, for the first time. The intensity of the LiCoO2 (104) plane is nearly invariant. The relative intensities of the LiCoO2 (113) plane were decreased by increasing RF power. The peak locations of the Li (002) and LiCoO2 (104) were not changed. It was found that Li (002) relative intensities affect the all investigated parameters for the LiCoO2 thin films. Especially, transmittance value increased about 20%. The band gap of the deposited film was changed 100–300 meV drastically. Deposited samples are shown high transparency in the visible region. Randles circuit was used for the equivalent circuit model. Nyquist plots, fitting parameters values and value of the circuit elements were estimated by ZSim software.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    AtıfScopus4WoS3OpenAlex4
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  • MakaleAçık Erişim2017Scopus SJRQ2
    Taguchi Approach for Optimization of Parameters that Effect Grain Size of Cast A357 Alloy

    Çolak, M.; Dlşplnar, D.

    Grain refining and modification are common foundry practice for improving properties of cast Al-Si alloys. In general, these types of treatments provide better fluidity, decreased porosity, higher yield strength and ductility. However, in practice, there are still some discrepancies on the reproducibility of the results from grain refining and effect of the refiner's additions. Several factors include the fading effect of grain refinement and modifiers, inhomogeneous dendritic structure and non-uniform eutectic modification. In this study, standard ALCAN test was used by considering Taguchi's experimental design techniques to evaluate grain refinement and modification efficiency. The effects of five casting parameters on the grain size have been investigated for A357 casting alloy. The results showed that the addition of the grain refiner was the most effective factor on the grain size. It was found that holding time, casting temperature, alloy type and modification with Sr were less effective over grain refinement.

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  • MakaleYalnız künye2017Scopus SJRQ1
    A study on some physical properties of a Pb-doped GaAs thin film produced by thermionic vacuum arc

    Şenay, Volkan; Özen, Soner; Pat, Suat; Korkmaz, Şadan

    A 155 nm Pb-doped GaAs thin film was deposited on a glass substrate by means of the thermionic vacuum arc technique in 30 s using GaAs and Pb pellets as source materials. Tools and techniques such as an optical reflectometer, UV-VIS-NIR spectrophotometer, FESEM, EDX, AFM and optical tensiometer were employed to investigate the physical properties of the produced film. From the optical investigations, the refractive index at the wavelength of 632.8 nm and optical band gap of the film were found to be 4.03 and 1.13 eV respectively. It was observed that Pb doping increased the value of refractive index and decreased the band gap value. A uniform surface morphology with fine grain covering the entire surface was observed through the FESEM and AFM studies while 50–80 nm grain size and 2.22 nm root mean square roughness values were obtained. The EDX analysis confirmed the presence of Ga, As and Pb elements in the film. The wetting experiments revealed that the contact angle value was dependent on the liquid used. The surface free energy calculated with OWRK/Fowkes and Equation of State approaches were about 26 mN/m.

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  • MakaleYalnız künye2017Scopus SJRQ2
    The surface morphology research of the BGaN thin films deposited by thermionic vacuum arc

    Özen, Soner; Pat, Suat; Şenay, Volkan; Korkmaz, Şadan

    In this paper, BGaN thin films with two different thicknesses were deposited on two different substrates and their surface morphologies were investigated. The amorphous glass and semi-crystalline polyethylene terephthalate substrates were selected. At the same time, two different deposition angles are selected with a view to the effect of deposition angle on surface morphology. The surface and optical properties were determined by using X-ray diffractometer (XRD), atomic force microscope (AFM), spectroscopic ellipsometry (SE) and optical interferometer. The thicknesses of thin films on substrates are about 30 nm and 40 nm. According to the atomic force microscope images, small-dimensional grains observed on relatively large grains. The roughness values of the thin films on the polyethylene terephthalate substrate are lower than on the glass substrate.

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  • MakaleAçık Erişim2017Scopus SJRQ1
    An energy prediction algorithm for wind-powered wireless sensor networks with energy harvesting

    Kosunalp, Selahattin

    Energy harvesting (EH) from environmental energy sources has the potential to ensure unlimited, uncontrollable and unreliable energy for wireless sensor networks (WSNs), bringing a need to predict future energy availability for the effective utilization of the harvested energy. The majority of previous prediction approaches have exploited the diurnal cycle dividing the whole day into equal-length time slots in which predictions were carried out in each slot independently. This is not, however, efficient for wind energy as it exhibits non-controllable behaviour in that the amount of energy to be harvested varies over time. This paper proposes a novel approach to predict the wind energy for EH-WSNs depending on the energy generation profile of latest condition. The distinctive feature of the proposed approach is to consider the recent conditions in current-day, instead of past-day's energy generation profiles. The performance of the proposed algorithm is evaluated using real measurements in comparison with state-of-art approaches. Results show that the proposed strategy significantly outperforms the two popular energy predictors, EWMA and Pro-Energy.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 13 · İklim Eylemi
    AtıfScopus48WoS36OpenAlex51
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  • MakaleAçık Erişim2017Scopus SJRQ1
    NOTETAKING SKILLS INSTRUCTION FOR DEVELOPMENT OF MIDDLE SCHOOL STUDENTS’ NOTETAKING PERFORMANCE

    Ilter, Ilhan

    The objective of this study was to investigate the effects of explicit instruction in notetaking skills on the notetaking performance of seventh-grade students at different reading ability levels. The students in the notetaking instruction condition (NTI) received classroom-based notetaking skills instruction (approximately 40 minutes) every week for 10 weeks. The comparison condition students (CNT) were asked to use conventional notetaking (CNT) that was embedded within the daily social studies lessons. The participants’ reading comprehension abilities were identified through the Sentence Verification Technique, which consisted of a 16-item expository text. A notetaking performance test (NTPT) was used to assess the effect of notetaking skills instruction on two dimensions of the participants’ notes (verbatim copying and terse value). The results demonstrated that the terse value of students’ notes in the NTI condition was significantly better than that of the students in the CNT condition. The students in the NTI condition reduced their percentage of verbatim copying and used fewer words to cover more main concepts in the NTPT that followed the instructional intervention. Surprisingly, the students at low reading ability showed the greatest gains in notetaking performance from verbatim copying to terse notetaking.

    • SDG 4 · Nitelikli Eğitim
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  • MakaleAçık Erişim2017Scopus SJRQ2
    Some approaches to multi criteria decision making based on exponential operations of simplified neutrosophic numbers

    Şahin, Rdvan; Liu, Peide

    Simplified neutrosophic set (SNS) is a powerful tool that attracts the attention of many scholars in dealing with uncertainty and vagueness. A SNS is based on a combination of simplified neutrosophic numbers (SNNs), whose its basic components are characterized by a truth-membership degree, an indeterminacy-membership degree and a falsity-membership degree of an object in evaluation data. Aggregation operators used to synthesize simplified neutrosophic information is commonly not very effective in case where the criteria weights provided by decision makers are in form of SNNs rather than exact real numbers. In this paper, we propose two new operational laws in which the bases are positive real numbers and interval numbers, respectively and the exponents are SNNs, and discuss some of their desired properties. Then we apply them to derive two weighted exponential aggregation operators, such as the simplified neutrosophic weighted exponential aggregation (SNWEA) operator and dual simplified neutrosophic weighted exponential aggregation (DSNWEA) operator. Additionally, two approaches for multi-criteria decision-making (MCDM) problems under the neutrosophic weight data are explored by applying these aggregation operators. At the end of the study, a convenient example is provided to demonstrate the availability and effectiveness of the proposed methods.

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  • MakaleAçık Erişim2017
    Concept-teaching practices in social studies classrooms: Teacher support for enhancing the development of students’ vocabulary

    İlter, İlhan

    The purpose of this study is to describe social studies teachers’ perceptions related to their practices in teaching concepts within the context of social studies instruction in order to enhance students’ vocabulary development in their classes. The study focuses on how students’ breadth and depth of vocabulary knowledge is supported by teachers’ experiences and their self-reported practices in relation to teaching social studies content. The study has a qualitative research design and has been conducted with 35 middle-school social studies teachers selected in accordance with maximum variation sampling. A semi-structured interview form has been used to determine teachers’ perceptions and viewpoints, and data has been analyzed using content analysis techniques. Results show that the teachers’ espoused practices for enhancing social studies vocabulary and for assessing its overall development process supports widely accepted understanding and ideas on effective concept teaching and alternative assessment procedures. Some examples of these practices and assessment measures include interactive word-walls (ABC graffiti), contextualized vocabulary instruction, word analogy, semantic maps, vocabulary self-collection strategy, and concept circles. However, the majority of practices reported by the teachers reflect traditional tasks and methods that ignore how new concepts were acquired and also focus more on the definitional knowledge of words. Further research should include teacher observations along with interviews to validate actual classroom practices.

    • SDG 4 · Nitelikli Eğitim
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  • MakaleYalnız künye2017Scopus SJRQ2
    Adsorptive properties of As(III) from aqueous solution using magnetic nickel ferrite (NiFe2O4) nanoparticles: Isotherm and kinetic studies

    Karcioğlu Karakaş, Zeynep; Boncukcuoğlu, Recep; Karakaş, İbrahim Hakkı

    As(III) adsorption on NiFe2O4 nanoparticles were systematically investigated by controlling parameters such as stirring rate, pH, initial arsenic concentration, contact duration, temperature, and adsorbent dose. It was observed that the amount of adsorbed arsenic concentration is strongly depended on pH and temperature. The temperature and pH give rise to significant changes in the amount of adsorbed arsenic. As compared with Langmuir and Freundlich isotherms models, the latter is found to be well suited. Pseudo-first order, pseudo-second order, and intraparticle diffusion models were applied to adsorption equilibrium data obtained from the analysis of arsenic with diverse amount of initial concentration.

    • SDG 6 · Temiz Su ve Sanitasyon
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  • MakaleYalnız künye2017Scopus SJRQ2
    Solar Pond Window Technology for Energy-Efficient Retrofitting of Buildings: An Experimental and Numerical Investigation

    Cuce, Erdem; Cuce, Pinar Mert

    Windows are responsible for an important proportion of heat loss from building envelope due to inadequate insulative characteristics of traditional glazing products. In this respect, advanced glazing solutions are of vital importance to mitigate energy demand of buildings, thus to reduce carbon emissions. Therefore, in this research, a novel glazing technology called solar pond window is introduced, and it is numerically and experimentally investigated for different design configurations. The optimum design of this novel glazing covers four 5-mm-thick glass panes, two 20-mm-thick water layers, and one 20-mm-thick Krypton layer in the middle. The average heat transfer coefficient (U-value) of the optimum case is found to be about 0.40 W/m 2 K. If air is used as insulative gas in the interlayer, the U-value of the glazing is determined to be around 0.90 W/m 2 K, which is still competitive with the U-value range of argon-filled triple-glazed windows with low-e coatings. The fabrication cost of the optimum design of solar pond window is around €120/m 2. Overall, solar pond window technology is a cost-effective and energy-efficient glazing, which has a great potential to be the future of fenestration products as well as being capable of meeting the latest building fabric standards.

    • SDG 7 · Erişilebilir ve Temiz Enerji
    • SDG 13 · İklim Eylemi
    AtıfScopus10WoS7OpenAlex9
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  • MakaleYalnız künye2017Scopus SJRQ3
    Continuous contact problem of a functionally graded layer resting on an elastic half-plane

    Öner, E.; Adiyaman, G.; Birinci, A.

    In this study, the continuous contact problem of a functionally graded layer resting on an elastic half-plane and loaded by a rigid rectangular stamp is examined. The problem is solved assuming that the functionally graded (FG) layer is isotropic and the shear modulus and mass density vary exponentially throughout the layer's thickness. However, the body force of the elastic half-plane is neglected. In addition, it is assumed that all surfaces are frictionless and only compressive stress is transferred along the contact surfaces. The mathematical problem is reduced to a singular integral equation in which the contact stress under the rigid stamp is unknown using the Fourier integral transform and boundary conditions related to the problem. This singular integral equation is solved numerically using the Gauss-Chebyshev integration formula. The dimensionless contact stress under the rigid stamp, the initial separation loads and the initial separation distances between the FG layer and the elastic half-plane are obtained for various dimensionless quantities.

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  • MakaleAçık Erişim2017Scopus SJRQ3
    Debaryomyces hansenii as a new biocatalyst in the asymmetric reduction of substituted acetophenones

    Şahin, Engin

    Chiral secondary alcohols are convenient mediator for the synthesis of biologically active compounds and natural products. In this study fifteen yeast strains belonging to three food originated yeast species Debaryomyces hansenii, Saccharomyces cerevisiae and Hanseniaspora guilliermondii were tested for their capability for the asymmetric reduction of acetophenone to 1-phenylethanol as biocatalyst microorganisms. Of these strains, Debaryomyces hansenii P1 strain showed an effective asymmetric reduction ability. Under optimized conditions, substituted acetophenones were converted to the corresponding optically active secondary alcohols in up to 99% enantiomeric excess and at high conversion rates. This is the first report on the enantioselective reduction of acetophenone by D. hansenii P1 from pastırma, a fermented Turkish meat product. The preparative scale asymmetric bio reduction of 3-methoxy acetophenone 1g by D. hansenii P1 gave (R)-1-(3-methoxyphenyl) ethanol 2g 82% yield, and >99% enantiomeric excess. Compound 2g can be used for the synthesis of (+)-NPS-R-568 [3-(2-chlorophenyl)-N-[(1R)-1-(3-methoxyphenly) ethyl] propan-1-amine] which have a great potential for the treatment of primary and secondary hyper-parathyroidism. In addition, D. hansenii P1 successfully reduced acetophenone derivatives. This study showed that this yeast can be used industrially to produce enantiomerically pure chiral secondary alcohols, which can be easily converted to different functional groups.

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