Yazar "Baris, Deniz" seçeneğine göre listele

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    In Vitro Antimicrobial and Antioxidant Activity of Ethanol Extract of Three Hypericum and Three Achillea Species From Turkey
    (Taylor & Francis Inc, 2011) Baris, Deniz; Kizil, Murat; Aytekin, Cetin; Kizil, Goksel; Yavuz, Murat; Ceken, Bircan; Ertekin, A. Selcuk
    The 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 -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.
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    Novel bis(aminoalcohol)oxalamide organogelators and their diglycolylamide analogs: evaluation of gelation efficiency in various organic fluids
    (Tubitak Scientific & Technological Research Council Turkey, 2017) Colak, Mehmet; Baris, Deniz; Pirinccioglu, Necmettin; Hosgoren, Halil
    Three 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 alpha-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. H-1 NMR studies reveal the existence of temperature dependent network assembly/dissolution equilibrium and produce K-gel. 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.
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    Novel C2-symmetric macrocycles bearing diamide-diester groups
    (Amer Chemical Soc, 2008) Sunkur, Murat; Baris, Deniz; Hosgoren, Halil; Togrul, Mahmut
    We 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 H-1 NMR titration. Taking into account the host employed, important differences were observed in the K-a values of (R)-Am and (S)-Am for (S,S)-1 and (R,R)-1 hosts, K-S/K-R = 5.55 and K-R/K-S = 3.65, Delta Delta G(o) = 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.
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    Organogels as novel carriers for dermal and topical drug delivery vehicles
    (Pergamon-Elsevier Science Ltd, 2016) Uzan, Serhat; Baris, Deniz; Colak, Mehrnet; Aydin, Haluk; Hosgoren, Halil
    Aminoalcohol based bis-(aminoalcohol)oxalamides (BAOAs) (1,6-amino alcohol=leucinol, isoleucinol, valinol, phenyiglycinol, phenylalaninol and 2-amino-1-butanol) have been explored to develop drug depot systems and illustrated as a novel dermal and topical drug delivery vehicle for non-steroidal anti-inflammatory drug molecules. FAE's (Fatty acid ethyl and isopropyl esters) with different chain lengths, ethyl laurate, ethyl myristate, ethyl palmitate, isopropyl laurate, isopropyl myristate, isopropyl palmitate, have been chosen as they are biocompatible organic fluids used typically in cosmetic industry. Ibuprofen (Ib), acting as a model drug, was entrapped in the supramolecular organogels. The release behavior of Ib molecules in the supramolecular organogels was investigated by using UV-vis spectroscopy. The influence of the organogelator and drug concentration, pH values of the accepting media, and nature of solvent (different FAE's) on the release behavior of Ib was investigated under static conditions. The results indicated that the release rate of Ib from the supramolecular organogels was effectively retarded with an increase of the organogelator concentration. Also, the release rates of Ib increased on increasing the Ib content. Furthermore, the release behavior of Ib was found to be different at various pH values in buffers as accepting media. The study of the release kinetics indicated that the release behavior of Ib was in accord with the Higuchi equation and the diffusion-controlled mechanism involved in the Fickian model. These observations indicate that bis-(aminoalcohol)oxalamides gels may act as delivery vehicles for non-steroidal anti-inflammatory drug molecules and also show that the release profiles for such systems can be fine-tuned by the correct choice of gelator-FAE combination. (C) 2016 Elsevier Ltd. All rights reserved.
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    Synthesis of rigid and C2-symmetric 18-crown-6 type macrocycles bearing diamide-diester groups: enantiomeric recognition for ?-(1-naphthyl) ethylammonium perchlorate salts
    (Pergamon-Elsevier Science Ltd, 2010) Baris, Deniz; Seker, Sevil; Hosgoren, Halil; Togrul, Mahmut
    A series of rigid and chiral C-2-symmetric 18-crown-6 type macrocycles (S,S)-4, (S,S)-5, (S,S)-6 and (R,R)-2 bearing diamide-ester groups were synthesized. The binding properties of these macrocycles were examined for ot-(1-naphthypethylammonium perchlorates salts by an 1H NMR titration method. Taking into account the host employed, important differences were observed in the Ka values of (R)- and (S)-enantiomers of guests for macrocycles (S,S)-4 and (S,S)-6, Ks/KR = 3.6, and Ks/KR = 0.1 (KR/Ks = 10.3).6.,6,G= 3.19 and Delta Delta G= -5.77 kJ mol(-1), respectively. The results indicated excellent enantioselectivity of macrocyclic (S,S)-6 towards the enantiomers of alpha-(1-naphthyl)ethylammonium perchlorate salts. (C) 2010 Elsevier Ltd. All rights reserved.
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    Synthesis of rigid and C2-symmetric pyridino-15-crown-5 type macrocycles bearing diamide-diester functions: enantiomeric recognition for chiral primary organoammonium perchlorate salts
    (Pergamon-Elsevier Science Ltd, 2014) Seker, Sevil; Baris, Deniz; Arslan, Nevin; Turgut, Yilmaz; Pirinccioglu, Necmettin; Togrul, Mahmut
    Four novel C-2-symmetric macrocyclic compounds with a pyridine function and possessing amide and ester lingeages were prepared. The enantiomeric discrimination abilities of these macrocycles against alpha-phenylethylammonium and alpha-(1-naphthyl)ethylammonium perchlorate salts were measured by standard H-1 NMR titration techniques in DMSO-d(6). A binding constant ratio of 31 (Kbind(S)/Kbind(R)) for two enantiomers of alpha-(1-naphthyl)ethylammonium salt with the macrocyclic host (S,S)-4 bearing phenyl arms was observed, which corresponds to an enantiomeric discrimination of approximately 94%. Molecular dynamic calculations were performed for some of the supramolecular complexes to in order to gain insight into the mode of molecular recognition between the macrocyclic compounds and ammonium salts; these results were consistent with experimental observations, which may be relevant to those in biochemical processes occurring in organisms. (C) 2014 Elsevier Ltd. All rights reserved.
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    Two-component organogelators: combination of N?-alkanoyl-L-lysine with various N-alkanoyl-L-amino acids: additional level of hierarchical control
    (Taylor & Francis Inc, 2018) Colak, Mehmet; Baris, Deniz; Evcil, Murat; Demirel, Nadir; Hosgoeren, Halil
    Synthesis of two-component organogelation system was performed very easy and concise manner from N-epsilon-palmitoyl-L-lysine ethyl ester and N-epsilon-miristoyl-L-lysine ethyl ester in which they were used as base component and N-lauroyl-L-amino acids (amino acids:, alanine, leucine and phenylalanine as acid components.). And their organogelation properties were examined in different pharmaceutical fluids such as liquid paraffin, fatty acid ethyl, and isopropyl esters. In this way, gelation efficiency was ascertained variations of alkanoyl moieties and combination of different amino acids in the gelator structures. Characterization of gelators was performed via thermal measurement such as Tg and gel-sol enthalpy change; SEM and FTIR as optical methods.