Person: NOMA, Samir Abbas Ali
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NOMA
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Samir Abbas Ali
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Publication A new design to enhance the enzyme activities: Investigation of L-asparaginase catalytic performance by IMAC effect on g-C₃N₄ nanolayers(Springer, 2023-07-08) Sert, Buse; Acet, Ömür; Noma, Samir Abbas Ali; Osman, Bilgen; Odabaşı, Mehmet; Ocakoğlu, Kasim; NOMA, Samir Abbas Ali; OSMAN, BİLGEN; Fen Edebiyat Fakültesi; Kimya Bölümü; 0000-0001-8406-149X ; ABH-1773-2021; ABF-4791-2020Recently, graphite carbon nitride (g-C3N4) has come to the fore as a new material with its carbon-based two-dimensional structure, simple preparation procedure, and excellent physicochemical stability properties. This study aims to investigate the activity and kinetic studies of the L-asparaginase enzyme via immobilized metal ion affinity chromatography (IMAC) process of g-C3N4 nanolayers. Firstly, g-C3N4 nanolayers were synthetized and Ni2+ ions were binded their surfaces. The synthesized samples were investigated by SEM, ICP-MS, XRD, and FTIR. The highest L-ASNase adsorption on Ni2+-g-C3N4 nanostructures was 444.1 mg/g, at 3 mg/mL L-ASNase concentration. Optimal medium conditions for L-ASNase adsorption occurred at pH 8.0 and 25 degrees C. The immobilized enzyme showed improved stability relating to the soluble enzyme in extreme situations. On the other hand, the storage stability and reusability of the immobilized enzyme were found to be approximately 64 and 53% of the original activity after 29 days at room temperature and 10 cycles, respectively. From the Michaelis-Menten constants Km and Vmax, both of them decreased after immobilization compare to the free one. The obtained outcomes showed that the g-C3N4 is a suitable matrix for L-asparaginase immobilization with ideal catalytic efficiency and improved stability.[GRAPHICS].Publication Novel hybrid isoindole-1,3(2H)-dione compounds containing a 1H-tetrazole moiety: Synthesis, biological evaluation, and molecular docking studies(Wiley, 2022-03-07) Tan, Ayse; Kızılkaya, Serap; Ates, Burhan; Kara, Yunus; Noma, Samir A. A.; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Bölümü; ABH-1773-2021In this study, novel hybrid isoindole-1,3(2H)-dione compounds (10 and 11) carrying a 1H-tetrazole moiety were synthesized, characterized and their inhibitory properties against xanthine oxidase (XO) and carbonic anhydrase isoenzymes (hCA I and hCA II) were investigated. Allopurinol for XO and acetazolamide for carbonic anhydrase isoenzymes were used as positive standards in inhibition studies. In addition, compounds 8 and 9, which were obtained in the intermediate step, were also investigated for their inhibition effects against the three enzymes. According to the enzyme inhibition results, hybrid isoindole-1,3(2H)-dione derivatives 10 and 11 showed significant inhibitory effects against all three enzymes. Surprisingly, compound 8, containing a SCN functional group, exhibited a greater inhibitory effect than the other compounds against hCA I and hCA II. The IC50 values of compound 8 against hCA I and hCA II were found to be 3.698 +/- 0.079 and 3.147 +/- 0.083 mu M, respectively. Compound 8 (IC50 = 4.261 +/- 0.034 mu M) showed higher activity than allopurinol (IC50 = 4.678 +/- 0.029 mu M) and the other compounds against XO, as well. These results clearly show the effect of the SCN group on the inhibition. In addition, in silico molecular docking studies were performed to understand the molecular interactions between each compound and enzymes, and the results were evaluated.Publication Investigation of improved uricase release and kinetic parameters through dual affected responsive nanopolymers(Elsevier Sci Ltd, 2023-06-03) Noma, Samir Abbas Ali; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Bölümü; ABH-1773-2021Uricase suppresses the harmful effects of uric acid accumulation by the degradation of uric acid to allantoin. Maintaining enzyme stability is a major challenge. The stability issue can be avoided when using enzymes loaded into polymeric structures. For this purpose, uricase loaded into responsive nanopolymers (UO-RNPs) was synthesized. The characterizations such as SEM, FTIR, and zeta potential of UO-RNPs were performed. Maximum uricase loading to RNPs was investigated and the release performance of UO-RNPs also under variable conditions such as pH and temperature. On the other hand, loading yield (LY) and loading efficiency (LE) was founded 73.22 & PLUSMN; 3.62% and 71.24 & PLUSMN; 4.61%, while storage stability and reusability of the UO-RNPs were found to be about 68% and 51% of the original activity after 4 weeks and 10 cycles, respectively. From Lineweaver-Burk plot the Km was founded 0.192 and 0.327 mM for loaded and free uricase. While V max was founded 0.131 and 0.0714 & mu;M/min for free uricase and UO-RNPs, respectively. UO-RNPs showed promising matrices for high catalytic efficiency and enhanced stability. Up until now, as far as we know, the present study of the loaded uricase into responsive nanopolymers is the first attempt of uricase enzyme in such an investigation.Publication The cytotoxicity, DNA fragmentation, and decreasing velocity induced by chromium(III) oxide on rainbow trout spermatozoa(Springernature, 2022-04-04) Özgur, Mustafa Erkan; Ulu, Ahmet; Gürses, Canbolat; Özcan, Imren; Noma, Samir Abbas Ali; Koytepe, Süleyman; Ateş, Burhan; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Bölümü; ABH-1773-2021The present study aimed to determine the cytotoxicity of chromium(III) oxide micro particles (Cr2O3-Ps) in rainbow trout (Oncorhynchus mykiss) spermatozoa. Firstly, Cr2O3-Ps were synthesized and structurally characterized the surface, morphological for particle size and thermal properties. In addition, its structural and elemental purity was determined using energy-dispersive X-ray (EDX) spectrum and elemental maps. Structural purity, thermal properties, and stability of Cr2O3 -Ps were also examined in detail by performing thermal analysis techniques. The cytotoxicity of Cr2O3-Ps was measured by the observation of velocities, antioxidant activities, and DNA damages in rainbow trout spermatozoa after exposure during 3 h in vitro incubation. The straight line velocity (VSL), the curvilinear velocity (VCL), and the angular path velocity (VAP) of spermatozoa decreased after exposure to Cr2O3-Ps. While the superoxide dismutase (SOD) and the catalase (CAT) decreased, the lipid peroxidation increased in a dose-dependent manner. However, the total glutathione (tGSH) was not affected in this period. DNA damages were also determined in spermatozoa using Comet assay. According to DNA in tail (%) data, DNA damages have been detected with gradually increasing concentrations of Cr2O3-Ps. Furthermore, all of class types which are categorized as the intensity of DNA fragmentation has been observed between 50 and 500 mu g/L concentrations of Cr2O3-Ps exposed to rainbow trout spermatozoa. At the end of this study, we determined that the effective concentrations (EC50) were 76.67 mu g/L for VSL and 87.77 mu g/L for VCL. Finally, these results about Cr2O3-Ps may say to be major risk concentrations over 70 mu g/L for fish reproduction in aquatic environments.Publication Synthesis of 1,4-disubstituted-1,2,3-Triazole derivatives for investigation of inhibition and molecular docking studies against Xanthine Oxidase(Sciencein Publications, 2023-01-01) Mirdan, Mustafa Nabeel Mirdan; Erdemir, Güler Yağız; Noma, Samir Abbas Ali; Tok, Tuğba Taşkın; Ateş, Burhan; Altundaş, Aliye; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Bölümü; ABH-1773-2021This study evaluates the inhibition effect of new 1,4-disubstituted-1,2,3-triazoles against Xanthine Oxidase supplemented by molecular modelling. Nine compounds of 1,4-disubstituted-1,2,3-triazoles by Sharpless's approach have been synthesized in this report. The structures of the synthesized compounds were characterized using FT-IR, H-1 and C-13-NMR and Mass spectroscopies Among these synthesized molecules (5bromothiophen-2-yl)(1-(3-fluorobenzyl)-1H-1,2,3-triazole-4-yl)methanone (9f) and (5-Bromothiophen-2-yl(1-(4-methoxybenzyl)-1H-1,2,3-triazole-4-yl)methanone (9h) showed better activity against Xanthine oxidase (XO) compared to allopurinol. In the light of the XO inhibition results, triazoles having of ketone moiety (9f-i) were found to be more active than triazoles of ketone-free (9a-e). These results were supported by docking models. The docking calculations of the target XO with nine available compounds showed good binding energies with favourable binding interactions. These findings were particularly evident that 9f (BE -7.29 kcal/mol) and 9h (BE -7.59 kcal/mol) are represented encouraging higher inhibition properties towards xanthine oxidase (XO), compared to allopurinol as a reference compound. Significant binding energies and interactions obtained by performing the docking studies are demonstrated, in particular, that the compounds 9f and 9h may be more potential bio compounds than the positive compounds, allopurinol, and febuxostat.Publication Design of laccase-metal-organic framework hybrid constructs for biocatalytic removal of textile dyes(Pergamon-elsevier Science Ltd, 2022-04-01) Birhanlı, Emre; Boran, Filiz; Ulu, Ahmet; Yeşilada, Özfer; Ates, Burhan; Noma, Samir Abbas Ali; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Ana Bilim Dalı; ABH-1773-2021This study aims to present a simple and effective carrier matrix to immobilize laccase as opposed to complex and tedious immobilization processes and also to use it in the removal of textile dyes. For this purpose, Cobalt (Co) and Copper (Cu) based metal-organic frameworks (MOFs) were prepared and laccase was immobilized on two different MOFs via encapsulation. The characterization outcomes showed that laccase was well immobilized into MOF supports. Optimum pH and temperature were found for Lac/Co-MOF (pH 4.5 at 50 degrees C) and Lac/Cu-MOF (pH 5.0 at 50 degrees C). The Km (0.03 mM) and Vmax (97.4 mu mol/min) values of Lac/Cu-MOF were lower than those of Lac/Co-MOF (Km = 0.13 mM, Vmax = 230.7 mu mol/min). The immobilized laccases showed good reusability as well as improved resistance to temperature denaturation and high storage stability. For instance, the Lac/Co-MOF and Lac/Cu-MOF retained more than 58% activity after 4 weeks of storage at room temperature. Meanwhile, Lac/Co-MOF and Lac/Cu-MOF maintained 56.5% and 55.8% of their initial activity, respectively, after 12 reuse cycles. Moreover, thermal deactivation kinetic studies of immobilized laccases displayed lower k value, higher t1/2, and enhancement of thermodynamic parameters, which means better thermostability. Finally, the decolorization activities for the Lac/Co-MOF were 78% and 61% at the 5th cycle for Reactive Blue 171 andPublication Synthesis, characterization and inhibitor properties of benzimidazolium salts bearing 4-(methylsulfonyl)benzyl side arms(Elsevier, 2022-10-26) Güzel, Abdussamat; Noma, Samir Abbas Ali; Şen, Betül; Kazancı, Ali; Taşkın-Tok, Tuğba; Kolac, Turgay; Aktaş, Aydın; Ates, Burhan; Aygün, Muhittin; Gök, Yetkin; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Bölümü; ABH-1773-2021Herein, a series of N-heterocyclic carbene (NHC) precursors bearing sulfonyl moieties was prepared. 1-(4-(methylsulfonyl)benzyl)-3-alkylbenzimidazolium chloride salts were synthesized with the reaction of 1-alkylbenzimidazoles with 4-(methylsulfonyl)benzyl chloride. These compounds were characterized by using 1 H NMR, 13 C NMR, FT-IR spectroscopy and elemental analysis techniques. Molecular and crystal structures of compounds 2e and 2j were determined by using the single-crystal X-ray diffraction method. Furthermore, enzyme inhibitory properties of benzimidazolium salt were tested against xanthine oxidase (XO) and acetylcholinesterase (AChE), then determined the IC50 value range of XO were determined from 0.218 to 1.927 mu M, while the IC50 for AChE were determined from 1.328 to 5.22. Docking applications were used by using AutoDock4 in order to define the binding pose of the selected compounds, ( 2c, 2d and 2g ) and also to visualize the correlation of the generated optimal complexes. It is found that the compound 2g has good binding affinity (-11.24 kcal/mol) against AChE, on the other side, compound 2c shows the lowest binding energy (-8.32 kcal/mol) for the XO target. These findings and the defined compounds could be as potential agents to develop effective medicine for AChE and XO in the future.(c) 2022 Elsevier B.V. All rights reserved.Publication Fast curing multifunctional tissue adhesives of sericin-based polyurethane-acrylates for sternal closure(Amer Chemical Soc, 2022-09-06) Balcıoğlu, Sevgi; Noma, Samir Abbas Ali; Ulu, Ahmet; Karaaslan-Tunç, Merve Gokşin; Özhan, Onural; Koytepe, Süleyman; Parlakpınar, Hakan; Vardı, Nigar; Colak, Mehmet Cengiz; Ateş, Burhan; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Bölümü; 0000-0003-4165-0045; ABH-1773-2021The use of wire cerclage after sternal closure is the standard method because of its rigidity and strength. Despite this, they have many disadvantages such as tissue trauma, operatorinduced failures, and the risk of infection. To avoid complications during sternotomy and promote tissue regeneration, tissue adhesives should be used in post-surgical treatment. Here, we report a highly biocompatible, biomimetic, biodegradable, antibacterial, and UV-curable polyurethane-acrylate (PU-A) tissue adhesive for sternal closure as a supportive to wire cerclage. In the study, PU-As were synthesized with variable biocompatible monomers, such as silk sericin, polyethylene glycol, dopamine, and an aliphatic isocyanate 4,4'-methylenebis(cyclohexyl isocyanate). The highest adhesion strength was found to be 4322 kPa, and the ex vivo compressive test result was determined as 715 kPa. The adhesive was determined to be highly biocompatible (on L929 cells), biodegradable, and antibacterial (on Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus bacteria). Finally, after opening the sternum of rats, the adhesive was applied to bond the bones and cured with UV for 5 min. According to the results, there was no visible inflammation in the adhesive groups, while some animals had high inflammation in the cyanoacrylate and wire cerclage groups. These results indicate that the adhesive may be suitable for sternal fixation by preventing the disadvantages of the steel wires and promoting tissue healing.Publication Thioether-substituted benzimidazolium salts: Synthesis, characterization, crystal structure, and their inhibitory properties against acetylcholinesterase and xanthine oxidase(Elsevier, 2023-05-10) Yavuz, Kemal; Sen, Betül; Taşkın-Tok, Tuğba; Aktas, Aydın; Ateş, Burhan; Aygün, Muhittin; Gök, Yetkin; OSMAN, BİLGEN; Noma, Samir Abbas Ali; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Ana Bilim Dalı; ABF-4791-2020 ; ABH-1773-2021The sulfurous compounds are known as organosulfur, which has been associated with numerous biological activities in both natural products and synthetic organic compounds. In this work, we present the synthesis of a series of 4-(methylthio)benzyl substituted benzimidazolium salts. All compounds were characterized using NMR (1H and 13C) and FTIR spectroscopic methods as well as an elemental analysis technique. The molecular and crystal structures of the compound 1a were determined by X-ray crystallography revealing that the compound crystallized in the trigonal space group R-3. Enzyme inhibition studies demonstrated that a new series of sulfurous compounds precursors were highly potent inhibitors for xanthine oxidase (XO) and acetylcholinesterase (AChE) enzyme. The IC50 values were found in the range of 0.548 +/- 0.033 to 0.725 +/- 0.043 mu M for XO promising strategy for the treatment from gout disease, while IC50 values were found in the range 0.813 +/- 0.076 to 1.149 +/- 0.072 mu M toward AChE as the key enzyme promising strategy for the treatment of neurological disorders such as Alzheimer's disease (AD). Furthermore, pharmacodynamics studies prove the binding interaction patterns, structural orientations and drug potential of sulfide derivatives in the binding sites of xanthine oxidase (XO) and acetylcholinesterase (AChE) enzymes. Potential inhibitors (compounds 1d-f) were compared with standard compounds allopurinol (for XO) and donepezil (for AChE). Compared to the positive compound of target XO, the 4-vinylbenzyl group of potential compound 1f and the 4-methylbenzyl group of compound le more effectively formed electrostatic and hydrophobic interactions with the target's interaction site. While donepezil as standard compound interacts only at the peripheral anionic site of AChE, the related compounds interact with both regions (PAS and CAS sites) of the same target. These compounds were placed at the active sites of the respective targets by molecular docking method using AutoDock software. Binding energy, binding modes and interaction types were used to evaluate the series of 4-(methylthio)benzyl substituted benzimidazolium salts's ability to bind to each target. Binding energy lower than zero remarks spontaneous binding, and equal and/or lower than -5 kcal/mol remarks good binding. Besides XO, the related compounds show higher activity against the AChE enzyme. They can also be analyzed as strong candidate compounds in biological studies of related enzymes.Publication Synthesis of new anthraquinone compounds and evaluation of their considerable xanthine oxidase inhibitory activities(Arkat Usa Inc, 2022-01-01) Parladı, Ufuk; Yılmaz, Ülkü; Noma, Samir Abbas Ali; Ateş, Burhan; Küçükbay, Hasan; NOMA, Samir Abbas Ali; Fen Edebiyat Fakültesi; Kimya Bölümü; ABH-1773-2021A series of anthraquinone derivatives (1-11) was prepared using alkyl halides, quinizarin, and danthron. The structural analysis of new compounds was carried out by 1H, 13C NMR, IR, and UV-Vis spectroscopic techniques. Xanthine oxidase inhibitory activities of compounds were measured using allopurinol as a standard. Inhibition abilities were identified by measuring the uric acid formation at 294 nm at 37 degrees C. According to the IC50 values of the compounds, it was observed that all the compounds in the group had higher inhibition values than allopurinol.