Browsing by Author "Calimli, Mehmet Harbi"

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Ecotoxicological Effects of Bimetallic Pdni/Mwcnt and Pdcu/Mwcnt Nanoparticles Onto Dna Damage and Oxidative Stress in Earthworms
(Springernature, 2022) Kokturk, Mine; Altindag, Fikret; Nas, Mehmet Salih; Calimli, Mehmet Harbi
Bimetallic nanoparticles are synthesized using two different metal elements and used recently in many fields. However, limited studies related to the ecotoxic effects of nanoparticles available in the literature. The purpose of this study is to synthesize and characterize bimetallic PdCu/MWCNT and PdNi/MWCNT NPs and investigate their ecotoxic effects on earthworms. For this purpose, we injected approximately 20 mu L of various concentrations of bimetallic PdCu/MWCNT and PdNi/MWCNT NPs (1, 10, 100, 1000, and 2000 mg/L) into the coelomic space of earthworms. We evaluated survival rate, malformations, reactive oxygen species (ROS) level, 8-OHdG content, and histopathological changes in earthworms at the 48th hour after exposure. PdCu/MWCNT and PdNi/MWCNT NPs were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) pattern, and Raman-scattering spectroscopy. Toxicological examinations showed that PdCu/MWCNT NPs reduced the survival rate of earthworms (2000 mg/L, 84%) and caused various malformations (various lesions, thinning, swelling, and rupture), but nonsignificant effects of survival rate and malformations were observed in earthworms using PdNi/MWCNT NPs. The histopathological examinations of earthworm tissues exposed with PdNi/MWCNT determined that tissues in all treatment groups had a normal histological appearance. However, at a concentration of 2000 mg/L of PdCu/MWCNT NPs, atrophy in the longitudinal muscle layer and less degenerative cells in the epidermis layer were observed in earthworm tissues. It was determined that PdNi/MWCNT and PdCu/MWCNT NPs caused significant increases in ROS levels and 8-OHdG activity in earthworm tissues after 48 h. Finally, our results demonstrated that the toxicity of PdNi/MWCNT NPs was detected to be lower than PdCu/MWCNT NPs. However, both nanoparticles may pose a toxicological risk at high concentrations (1000 and 2000 mg/L). These findings will provide valuable information to studies on the use of PdNi/MWCNT NPs in wastewater treatment systems, industrial and medical fields, which have been determined to have less ecotoxicological risk.
The Fifth Version of Atom Bond Connectivity Index (Abc5) of an Infinite Class of Dendrimers
(Natl inst Optoelectronics, 2011) Calimli, Mehmet Harbi
The atom-bond connectivity index-5(ABC(5)) is a new topological index defined as; ABC(5)(G) = Sigma(uv is an element of E(G)) root M-u + M-v - 2/MuMv where M-u denotes the product of the degrees of adjacent vertices of u. In this paper we compute this new topological index for an infinite class of dendrimers.
Has Pdcu@go Effect on Oxidant/Antioxidant Balance? Using Zebrafish Embryos and Larvae as a Model
(Elsevier Ireland Ltd, 2023) Ucar, Arzu; Yeltekin, Asli Cilingir; Kokturk, Mine; Calimli, Mehmet Harbi; Nas, Mehmet Salih; Parlak, Veysel; Atamanalp, Muhammed
Industrial products containing PdCu@GO can gain access to the aquaculture environment, causing dangerous effects on living biota. In this study, the developmental toxicity of zebrafish treated with different concentrations (50, 100, 250, 500 and 1000 mu g/L) of PdCu@GO was investigated. The findings showed that PdCu@GO administration decreased the hatchability and survival rate, caused dose-dependent cardiac malformation. Reactive oxygen species (ROS) and apoptosis were also inhibited in a dose-dependent manner, with acetylcho-linesterase (AChE) activity affected by nano-Pd exposure. As evidence for oxidative stress, malondialdehyde (MDA) level increased and superoxide dismutase (SOD), catalase (CAT) glutathione peroxidase (GPx) activities and glutathione (GSH) level decreased due to the increase in PdCu@GO concentration. Our research, it was determined that the oxidative stress stimulated by the increase in the concentration of PdCu@GO in zebrafish caused apoptosis (Caspase-3) and DNA damage (8-OHdG). Stimulation of ROS, inflammatory cytokines, tumor Necrosis Factor Alfa (TNF-alpha) and interleukin - 6 (IL-6), which act as signaling molecules to trigger proin-flammatory cytokine production, induced zebrafish immunotoxicity. However, it was determined that the in-crease of ROS induced teratogenicity through the induction of nuclear factor erythroid 2 level (Nrf-2), NF-icB and apoptotic signaling pathways triggered by oxidative stress. Taken together with the research findings, the study contributed to a comprehensive assessment of the toxicological profile of PdCu@GO by investigating the effects on zebrafish embryonic development and potential molecular mechanisms.
Hidrate Edimiş Uleksit Mineralinin Borik Asit Çözeltisindeki Kinetik Parametrelerinin İncelenmesi
(2018) Calimli, Mehmet Harbi; Tunç, Mehmet
Bor bileşiklerinin üretiminde kullanılan Uleksit çok önemli bir bor mineralidir. Bu çalışmada hidrate edilmiş uleksit minerali ve orginal mineralinin borik asit çözeltisindeki kinetik parametreleri incelenmiştir. DTA diyagramına göre 170 o C’ye kadar mineral yapısında değişim olmadığı görülmüştür. Bu sıcaklık aralığında çözünme kinetiğinin arttığı gözlendi. SEM görüntülerinden 170 o C’ye kadar mineral gözeneklerinde açılmaların arttığı, bu sıcaklıktan sonra ise azaldığı gözlemlendi. Orijinal uleksite ait kinetik parametreler değerlendirildi. Mineralin borik asitteki çözünme kinetiği aşağıda ki gibi bulundu; 1-(1-X)-1 = [2.02(Rp)-1,013[CA]0 0,4579(S.L-1)-0650(M.S)0,0545e-2649,12T-1].t
In Situ Preparation of Tio2/F-mwcnt Catalyst Using Pluronic F127 Assisted Sol-Gel Process for Sonocatalytic Degradation of Methylene Blue
(Academic Press inc Elsevier Science, 2023) Yildiz, Adnan; Yesilbas, Omer Faruk; Nas, Mehmet Salih; Calimli, Mehmet Harbi; Bayat, Ramazan; Sen, Fatih
In this study, titanium dioxide-Pluronics @F127/functionalized-multi walled carbon nanotubes (TiO2-F127f-/ MWCNT) nanocatalysts were prepared, characterized, and used in methylene blue (MB) degradation under ul-trasonic conditions. The characterization studies were performed using TEM, SEM, and XRD analyses to reveal the morphological and chemical properties of TiO2-F127/MWCNT nanocatalysts. To detect the optimum pa-rameters for MB degradation using TiO2-F127/f-MWCNT nanocatalysts, several experimental parameters were conducted at various conditions such as different temperatures, pH, catalyst amount, hydrogen peroxide (H2O2) concentration, and various reaction contents. Transmission electron microscopy (TEM) analyses showed that TiO2-F127/f-MWCNT nanocatalysts consisted of a homogenous structure and have a 12.23 nm particle size. The crystalline particle size of TiO2-F127/MWCNT nanocatalysts was found to be 13.31 nm. Scanning electron microscope (SEM) analyses revealed the surface structure of TiO2-F127/f-MWCNT nanocatalysts turned to be modified after TiO2 loaded on MWCNT. Under the optimum conditions; pH: 4, MB concentration: 25 mg/L, H2O2 concentration: 30 mol/L, reaction time: and catalyst dose: 24 mg/L, chemical oxygen demand (COD) removal efficiency reached a maximum of 92%. To detect the radical effectiveness, three scavenger solvents were tested. Reuse experiments revealed that TiO2-F127/f-MWCNT nanocatalysts retained 84.2% catalytical activity after 5 cycles. Gas chromatography-mass spectrometry (GC-MS) was successfully used to identify the generated in-termediates. Based on the experimental results, it has been suggested that center dot OH radicals are the main active species responsible for the degradation reaction in the presence of the TiO2-F127/f-MWCNT nanocatalysts.
In Vivo Biochemical Evaluations of Some Β-Lactam Group Antibiotics on Glutathione Reductase and Glutathione S- Transferase Enzyme Activities
(Pergamon-elsevier Science Ltd, 2019) Turkan, Fikret; Huyut, Zubeyir; Huyut, Mehmet Tahir; Calimli, Mehmet Harbi
Objectives: The aim of this study was to investigate whether some of the cephalosporin group antibiotics have inhibition effects on GR and GST enzymes with important functions in the metabolic pathway. Methods: In this study, some selected cephalosporin group antibiotics on GST and GR enzyme was carried out using 96 rats. 16 groups (16 x 6) were created from these rats, divided to another 4 groups (4 x 24). The resulting groups were named as sham groups, cefazolin groups, cefuroxime groups and cefoperazone groups, respectively. The antibiotics used were injected to cefazolin, cefuroxime and cefoperazone groups. The inhibition effects of the antibiotics were measured in the different time intervals (1st, 3th, 5th, 7th). The statistical investigation of the results was performed using the SPSS software program. Results: Results revealed the complex effects of the tested substances on GR and GST activity at different time intervals and in different tissues (p < 0.05). This indicated that the tested substances could be exposed to different interactions in vivo. Conclusion: The tested antibiotics showed some significant inhibition effects on the GST and GR enzyme activity in some tissues of brain, eye and muscle. The interaction of enzyme - the drug is a key factor to highlight the toxicological mechanism. For this reason, the results obtained from in vivo experiments are crucial to explane the physiological properties of the enzymes.
In Vivo Biochemical Evaluations of Some Β-Lactam Group Antibiotics on Glutathione Reductase and Glutathione S-Transferase Enzyme Activities (Vol 231, 116572, 2019)
(Pergamon-elsevier Science Ltd, 2023) Turkan, Fikret; Huyut, Zubeyir; Huyut, Mehmet Tahir; Calimli, Mehmet Harbi
Inhibition Effects of Isoproterenol, Chlorpromazine, Carbamazepine, Tamoxifen Drugs on Glutathione S-Transferase, Cholinesterases Enzymes and Molecular Docking Studies
(Taylor & Francis inc, 2021) Turkan, Fikret; Calimli, Mehmet Harbi; Kanberoglu, Gulsah Saydan; Karaman, Muhammet
Nowadays, inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and glutathione S-transferases (GSTs) have been a very crucial issue for pharmacological treatments of several disasters. Herein, we investigated inhibition effects of Tamoxifen (TAM), Isoprenaline (ISO), Chlorpromazines (CPZ) and Carbamazepine (CBZ) on GST, AChE, BChE and then molecular structures and active sides of the tested drugs by molecular docking process. The enzyme activity results showed that nearly the whole tested drugs inhibited GST, BChE, AChE efficiently. Chlorpromazine was found to be the best inhibitor for the GST enzyme and the Ki value of this drug was found to be 42.83 +/- 8.52 nM. Besides, Isoproterenol drug with the Ki value of 51.80 +/- 9.44 nM was found to be the most effective inhibitor on the AChE enzyme. Molecular docking studies showed that the receptor-binding sites of GST, AChE, and BChE were found to 1.069, 1.090, and 1.15 of Sitecore and 0.992, 1.113, and 1.217 of Dscore, respectively. The method was validated by doing validation studies and these validations revealed that re-docked ligands located a very closed position with co-crystallized ligand into the active site for all receptors. Calculation studies for determining the possible enzyme inhibition mechanism with the used drugs revealed that amino and aromatic ring in the structure of the drugs used are effective in inhibition reactions. Communicated by Ramaswamy H. Sarma
May Pdcu@f-Mwcnt Nps Be an Ecotoxicologic Risk
(Wiley, 2023) Alak, Gonca; Yeltekin, Asli Cilingir; Kokturk, Mine; Nas, Mehmet Salih; Parlak, Veysel; Calimli, Mehmet Harbi; Atamanalp, Muhammed
The mechanisms of various metal nanoparticles (NPs) are still a matter of debate in aquatic toxicology. In order to close this gap, the number of studies on this subject is increasing. The aims of this study are to explore the interactions of PdCu@f-MWCNT NPs with zebrafish and get to know if it has an ecotoxicological risk. In this study, we synthesized, characterized PdCu@f-MWCNT NPs, and investigated its ecotoxicological effects. The chemical and morphological structures of PdCu@f-MWCNT nanomaterials were elucidated with advanced analysis techniques such as scanning electron microscope (SEM), X-ray spectrophotometer (EDX), transmission electron microscope (TEM), and X-ray diffraction (XRD) analyses. The ecotoxicological risks were investigated by conducting biochemical analyses and malformation defects in zebrafish. The results were obtained using multiple marker applications including oxidative stress parameters, proinflammatory cytokine expressions, DNA damage, and apoptosis markers. The obtained findings showed embryonic development, survival rate, and incidence of malformation increasing in parallel with the dose increase in zebrafish exposed to PdCu@f-MWCNT NPs at 10-1000 mu g/L levels. Despite the observed decreases in antioxidant enzyme activities, GSH level, AChE activity, and NRF-2 level, inductions in malondialdehyde (MDA) level, IL-6, TNF-alpha, NF-kB, DNA damage, and apoptosis levels were observed with increasing dose. Considering these findings, it has been determined that there are toxic effects in zebrafish at all levels above the concentration that we examine as a safe dose (10 mu g/L). The effects of all studied concentrations of this NP above the safe dosage, especially on oxidative stress, malformation, and immune system, were found to be quite significant. The more widespread use of nanotechnology in the future will mean more contact of aquatic organisms with NPs. As a result, it is clearly seen that these organisms, which form the important link of the food chain, and the aquatic environment are living at risk conditions.
Pdruo2/Pvp Nanomaterial as a Highly Selective, Stable, and Applicable Potentiometric Sensor for the Detection of Cr3+
(Springer Wien, 2024) Cevik, Kenan; Yildiz, Ilyas; Yildiz, Adnan; Nas, Mehmet Salih; Alma, Mehmet Hakki; Calimli, Mehmet Harbi
PdRuO2/PVP nanomaterial was synthesized using a straightforward method and characterized using advanced analytical methods such as TEM, XRD, XPS, elemental mapping and SEM. The synthesized PdRuO2/PVP nanomaterial was used as an ionophore in potentiometric sensor electrodes and successfully adapted to Cr3+ ion detection in a large number of aqueous samples. Several experimental parameters of the PdRuO2/PVP sensor such as potentiometric behavior, selectivity, repeatability, response time, pH, titration, and recovery in real samples were investigated. Potentiometric behavioral characteristics were performed in the concentration range 1 x 10(-6)-1.0 x 10(-1) M. The repeated experiments performed six times showed that there was no deviation in the measurements. The limit of detection of the PdRuO2/PVP potentiometric sensor was very low with a value of 8.6 x 10(-8) M. The potentiometric measurements showed that the synthesized PdRuO2/PVP ionophore was highly effective in detecting Cr3+ in a wide pH range of 2.0-8.0 and was found to have a shelf life of over 1 year. As a result, the synthesized PdRuO2/PVP electrode material was found to be highly selective, stable, and applicable for Cr3+ detection.
Synthesis, Characterization, and Utilization of Niceo2@f-mwcnt/Eda Nanoparticles as Electrode Materials for Supercapacitor Application
(Pergamon-elsevier Science Ltd, 2023) Yildiz, Adnan; Demirel, Serkan; Nas, Mehmet Salih; Calimli, Mehmet Harbi
Metal oxide and carbon nanotube-based materials are widely preferred in supercapacitor and electrochemical sensor applications due to their interesting physicochemical structure. In this paper, we report the synthesis, characterization, and utilization of NiCeO2@f-MWCNT/EDA nanoparticles as electrode materials for supercapacitor applications. The characterization studies of NiCeO2@f-MWCNT/EDA nanomaterials were performed using X-ray diffraction (XRD), Transmission electron microscope (TEM), and Raman spectroscopy apparatus. The characterization methods revealed a good distribution of NiCeO2 on f-MWCNT/EDA and formed a new structure of NiCeO2@f-MWCNT/EDA nanoparticles. Electrochemical studies of NiCeO2@f-MWCNT/EDA nanoparticles showed a significant specific capacitance of between 2385 and 603 Fg  1 with good cyclic stability of 1000 cycles with capacity retention between 42% and 1.4% at 10 mV/s scan rate. The obtained results reveal that the prepared NiCeO2@f-MWCNT/EDA nanoparticles are promising electrode materials for supercapacitor devices.
Textile Dyes Maxilon Blue 5g and Reactive Blue 203 Induce Acute Toxicity and Dna Damage During Embryonic Development of Danio Rerio
(Elsevier Science inc, 2021) Kokturk, Mine; Altindag, Fikret; Ozhan, Gunes; Calimli, Mehmet Harbi; Nas, Mehmet Salih
Common textile dyes used in various industrial sectors are organic compounds and considered for the aquatic environment as pollutants. The textile dye industry is one of the main sectors that have serious impacts on the environment due to a large amount of wastewater released into the ecosystem. Maxilon blue 5G (MB-5G) and Reactive Blue 203 (RB-203) are widely used textile dyes. However, their potential toxicity on living organisms remains to be elucidated. Here, we investigate the acute toxicity and genotoxicity of MB-5G and RB-203 dyes using the zebrafish embryos/larvae. Embryos treated with each dye for 96 h revealed LC50 values of acute toxicity as 166.04 mg L-1 and 278.32 mg L-1 for MB-5G and RB 203, respectively. When exposed to MB-5G and RB-203 at different concentrations (1, 10, and 100 mg L-1) for 96 h, the expression of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a marker of oxidative DNA damage, significantly increased in brain tissues as compared to control. MB-5G and RB-203 resulted in common developmental abnormalities including tail malformation, microphthalmia, pericardial edema, curved body axis, and yolk sac/pericardial edemas. Moreover, at its highest dose (100 mg L-1), RB-203 caused premature hatching after 48 h, while MG-5G did not. Our results collectively reveal that the textile dyes MB-5G and RB-203 cause genotoxicity and teratogenicity during embryonic and larval development of zebrafish. Thus, it is necessary to eliminate these compounds from wastewater or reduce their concentrations to safe levels before discharging the textile industry wastewater into the environment.
Uleksitin Borik Asit Çözeltisinde Çözünme ve Kinetik Parametre Davranışlarının İncelenmesi
(2020) Kocakerim, Mehmet Muhtar; Calimli, Mehmet Harbi; Tunç, Mehmet
Günümüzde bor ve türevleri yaygın olarak endüstri ve teknolojik alanlarda kullanılmaktadır. Bor mineralleri savunma sanayi, sağlık, mutfak ekipmanları vb. alanlarda kullanılan saf bor kimyasallarını elde etmek için ana kaynaklardır. Bu çalışmada, ilk kez, uleksitin borik asit çözeltisindeki çözünme davranışları ve kinetik paramaterleri rapor edilmiştir. Uleksiti borik asitte çözmek önemlidir, çünkü bir çözücü olarak borik asit safsızlıkların oluşumun engeller ve bu nedenle çalışmamız literatürde bir ilktir. Bu bağlamda, uleksitin çözünmesi, sıcaklıklar, asit konsantrasyonu, katı/sıvı oranı, partikül boyutu, çözünme hızı ve karıştırma hızı gibi çeşitli deneysel parametreler altında incelenmiştir. Deneysel bulgular, üleksitin çözünme kinetiğinin sıcaklık ve asit konsantrasyonundaki artış ve partikül boyutundaki azalma ile arttığını, ancak asitteki karıştırma hızı ile azaldığını göstermiştir. Ayrıca, uleksitin borik asittteki çözmesi ve aktivasyon enerjisi değerlendirildi. Sonuçta özünme kinetiğinin kimyasal kontrol modeli ile uyumlu olduğu ve aktivasyon enerjisinin 22,024 kJ mol-1 olduğu bulundu.