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Öğe Characterisation and biological activities of synthesised copper oxide nanoparticles from the Pimpinella anisum L. aqueous extract(Akademiai Kiado Zrt, 2024) Sucu, S.; Demir, N.Nanoparticles can be synthesised by several methods. Due to the long duration, high cost, and toxic by-products of chemical and physical methods, the biological method has become more preferred. Among various sources such as bacteria, fungi, or yeast, the use of plants in biological synthesis has proven to be the most ideal. Many metals can be used in the biological method, including copper oxide (CuO). In this study, copper oxide nanoparticles (CuONPs) were synthesised using Pimpinella anisum L. aqueous extract. For characterisation of the CuONPs, UV-Visible Spectroscopy (UV-Vis), Scanning Electron Microscopy (SEM), Energy Dispersion Spectroscopy (EDS), and Fourier Transform Infrared Spectroscopy (FT-IR) analyses were performed. The biological activity of the P. anisum extract and CuONPs was determined using DNA cleavage (agarose gel electrophoresis), antioxidant (1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and hydrogen peroxide scavenging activity), mutagenic (Ames/Salmonella test), and catalytic (methylene blue degradation) activities. In DNA cleavage activity test, CuONPs completely denatured DNA at high concentrations (100 and 200 mu g mL(-1)) due to their oxidative activity. The results showed that both the extract and CuONPs have antioxidant properties in DPPH and hydrogen peroxide scavenging activities. According to the mutagenicity, CuONPs did not have a mutagenic effect. In catalytic activity, CuONPs degraded methylene blue within 240 min by 99.45%.Öğe DFT Calculation, Molecular Docking, Biological Activity, and Crystal Structure of (E)-2-((4-tert-Butylbenzylimino)Methyl)-4-Methoxy-Phenol(Pleiades Publishing Inc, 2019) Zeyrek, C. T.; Tumer, Y.; Kiraz, A.; Demir, N.; Yapar, G.; Boyacioglu, B.; Yildiz, M.(E)-2-((4-tert-butylbenzylimino)methyl)-4-methoxyphenol is synthesized by the reaction of 4-tert-buthylbenzylamine with 5-methoxysalicylaldehyde. The structure of the Schiff base is investigated by FT-IR, UV-visible, and H-1 NMR, C-13 NMR, and X-ray data. Moreover, the molecular structure, molecular electrostatic potential surfaces (MEP), frontier molecular orbitals, and nonlinear optical properties (NLO) are also investigated by density functional theory (DFT) calculations. The experimental and calculated results show that the phenol-imine form of the compound is more favoured than the keto-amine form. The most energy favourable docked structures are obtained from the rigid molecular docking of the compound with DNA. The compound binds at the active site of DNA proteins by weak non-covalent interactions. UV-Vis spectroscopy studies of the interactions between the compounds and calf thymus DNA (CT-DNA) show that the compounds interact with CT-DNA via the electrostatic and intercalative binding. The compound inhibits the frameshift and base pair mutations in the absence of S9 mix with a high inhibition rate. Also, the molecular docking is made to identify the interaction between the ligand and DNA.Öğe DNA binding, DNA cleavage, antimicrobial activities, antimutagenic and anticancer studies of a Schiff base and its complexes(Wiley-Blackwell, 2016) Yildirim, N.; Demir, N.; Yildiz, M.[Anstract Not Available]Öğe Green synthesis of silver nanoparticles using Sorghum bicolor var. technicum seed extract, their characterisation and investigation of biological activities(Akademiai Kiado Zrt, 2023) Dalgic, B.; Demir, N.Synthesis of nanoparticles can be long and costly processes using physical and chemical methods. Biological synthesis of nanoparticles is known to be cheaper and easier than other methods. In this study, silver nanoparticles (AgNP) were obtained by biological synthesis, also known as green synthesis, using Sorghum bicolor var. technicum (Korn) Stapf ex Holland seed extract, popularly known as sorghum. AgNPs were characterised by SEM, EDS, TEM, FT-IR, and UV-Vis Spectroscopy. SEM images confirmed that the shape of AgNPs was spherical. TEM analysis showed that the average sizes of AgNPs ranged from 51 to 56 nm. EDS analysis confirmed the presence of AgNPs by detecting a silver ion peak at 3 KeV. UV-Vis spectroscopy analyses indicated that the brown-burgundy colour of AgNPs exhibited maximum absorbance at 450 nm. The biological activities of the extract and AgNPs were investigated through antimicrobial, antibiofilm, antioxidant, mutagenic, and DNA cleavage activity analyses. The extract exhibited the highest MIC value against Gram-positive bacterium Bacillus subtilis (0.62 mu g mL-1), whereas AgNPs demonstrated the highest antimicrobial activity specifically against Gram-negative bacterium Escherichia coli (0.31 mu g mL-1). The antibiofilm results revealed that the extract displayed the highest percentage of biofilm inhibition against B. subtilis, while AgNPs exhibited notable efficacy against both Candida albicans yeast and Pseudomonas aeruginosa bacterium. The antioxidant activities were evaluated using DPPH' and ABTS' thorn methods, and it was determined that both samples had high antioxidant activity. Mutagenicity of the extract and AgNPs were evaluated by the Ames/Salmonella test using two strains of Salmonella typhimurium (TA98 and TA100). The mutagenic activity of the extract increased depending on the concentration for both strains, while AgNP did not show mutagenicity at any concentration. The agarose gel electrophoresis method showed that the extract and AgNPs cleaved DNA in the presence of an oxidising agent.Öğe Synthesis and spectral, antimicrobial, anion sensing, and DNA binding properties of Schiff base podands and their metal complexes(Maik Nauka/Interperiodica/Springer, 2015) Yildiz, M.; Tan, E.; Demir, N.; Yildirim, N.; Unver, H.; Kiraz, A.; Mestav, B.Schiff base podands have been synthesized by reaction of triethylene glycol bis(4-aminophenyl) ether with salicylaldehyde, 5-substituted salicylaldehydes, and 2-hydroxy-1-naphthaldehyde. Manganese(II), iron(II), cobalt(II), nickel(II), and copper(II) complexes have been prepared from the salicylaldehyde-based podand via reaction with MCl2 center dot nH(2)O. The structures of the ligands and complexes have been studied by elemental analysis, FT-IR and UV-visible spectroscopy, H-1 and C-13 NMR, and thermogravimetric analysis. The UV-visible spectral and TG data suggest tetrahedral geometry of the metal complexes. The antimicrobial activities of the ligands and metal complexes have been evaluated as minimum inhibitory concentrations with respect to bacteria and yeast cultures. The interaction of the Schiff base podands with calf thymus DNA has been investigated by UV-visible spectroscopy, and intercalative binding to DNA has been found. The anion recognition ability of all Schiff base podands has been examined by UV-visible spectroscopy. A visually detectable color change has been observed upon addition of fluoride, cyanide, hydroxide, and acetate ions due to formation of 1: 1 H-complexes and/or deprotonation of the receptor. No significant color change has been observed upon addition of other anions such as dihydrogen phosphate, bromide, iodide, thiocyanate, perchlorate, and hydrogen sulfate.Öğe Synthesis of Silver Nanoparticles Using Porella pinnata L. Extract and Evaluation of Biological Activity(Pleiades Publishing Inc, 2024) Simsek, O.; Demir, N.; Erdener, D.; Karakas, I.; Dogru, N. HaciogluDeveloping an eco-friendly method for producing nanomaterials is an area of significant research and commercial interest owing to its numerous applications in various disciplines. This study used a simple green synthesis approach to produce silver nanoparticles (AgNPs) using Porella pinnata L. aqueous extract. Phytochemical constituents of P. pinnata were identified by Gas Chromatography and Mass Spectroscopy (GC-MS). The optical, structural, and morphological characteristics of the AgNPs were found using UV visible absorption spectroscopy (UV-Vis), Fourier transform infrared spectroscopy (FTIR), Zeta Potential, and scanning electron microscope (SEM). The AgNPs had an average size of 76-84 nm and were mostly spherical. Considering the antimicrobial and antibiofilm activity results, both aqueous extract and AgNP have significant activities against different microorganisms based on the disc diffusion, broth microdilution, and antibiofilm methods. The P. pinnata and AgNPs extracts were significantly inhibited all test culture especially Acinetobacter baumanii ATCC 19606. The agarose gel electrophoresis method showed that extract and AgNP both cleaved DNA by hydrolytic and oxidative. Although both P. pinnata and AgNP extracts have dose-dependent antioxidant activity, AgNP is more effective. Thus, green synthesis AgNPs may be a new alternative therapeutic agent for infection therapy.Öğe Synthesis, antimicrobial activity, genotoxicity, DNA binding and DNA cleavage studies of new glycine methyl ester derivative Schiff base(Wiley-Blackwell, 2016) Yildirim, M. A.; Demir, N.; Yildiz, M.; Unver, H.[Anstract Not Available]
