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    The Cytotoxicity, DNA Fragmentation, and Decreasing Velocity Induced By Chromium(III) Oxide on Rainbow Trout Spermatozoa
    (Springer, 2022) Özgür, Mustafa Erkan; Ulu, Ahmet; Gürses, Canbolat; Özcan, İmren; Samir Abbas Ali, Noma; Köytepe, Süleyman; Ateş, Burhan
    The 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 µg/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 µg/L for VSL and 87.77 µg/L for VCL. Finally, these results about Cr2O3-Ps may say to be major risk concentrations over 70 µg/L for fish reproduction in aquatic environments.
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    Immobilization of α-Amylase onto Quantum Dots Prepared from Hypericum perforatum L. Flowers and Hypericum capitatum Seeds: Its Physicochemical and Biochemical Characterization
    (Springer/Plenum Publishers, 2023) Acari, Idil Karaca; Dik, Gamze; Bakar, Busra; Ulu, Ahmet; Onal, Yunus; Ates, Burhan
    Enzyme immobilization is an effective way to increase the catalytic activity and stability of the alpha-amylase (Amy) enzyme for industrial uses. For this purpose, carbon and graphene quantum dot (QDs) structures were prepared from Hypericum perforatum L. flowers (QD-1), and Hypericum capitatum seeds (QD-2) obtained from an herbalist in Hatay province of Turkey. Structural and morphological characterization of the prepared QDs and QDs/Amy were carried out by Fourier transform infrared spectrophotometer (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and energy dispersive X-ray (EDX). Meanwhile, biochemical characterizations such as optimum pH and temperature, kinetic parameters, effects of metal ions, organic solvents, and trypsin digestion on enzyme activity were performed and compared with free Amy. The Amy enzyme was immobilized with an activity efficiency of 71.15% for QD-1/Amy, and 81.51% for QD-2/Amy under optimal conditions. The difference in activity efficiency between QD-1/Amy and QD-2/Amy was likely due to a change in the surface porosity of QDs structures. While the optimal pH value of all three forms of Amy was recorded as 6.0, their optimal temperature was found to be 40 degrees C. The activation energy (E-a) of the free Amy was found to be 4.81 kJ/mol, while it was 9.61 kJ/mol, and 3.20 kJ/mol for QD-1/Amy, and QD-2/Amy, respectively. K-m values were calculated as 1.18, 1.57, and 1.35 mg/mL for free Amy, QD-1/Amy, and QD-2/Amy, respectively, and V-max values were calculated as 37.52, 37.60, and 39.93 mu mol/min, respectively. Kinetic data revealed that the immobilized enzymes had lower substrate affinity compared to the free Amy. Besides, the QD-1/Amy and QD-2/Amy exhibited more stability than free Amy against metal ions, organic solvents as well as trypsin digestion due to the increment in conformational rigidity caused by changes in the secondary structures of the immobilized enzyme. For instance, after incubation with trypsin for 120 min, free Amy, QD-1/Amy, and QD-2/Amy retained approximately 20%, 35%, and 26% of initial activities, respectively. Finally, it can be proposed that the prepared carriers in this work may a useful to produce stable and active immobilized Amy to be used in industrial applications.
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    Investigation of toxic effects of amorphous SiO2 nanoparticles on motility and oxidative stress markers in rainbow trout sperm cells
    (Springer, 2019) Özgür, Mustafa Erkan; Ulu, Ahmet; Özcan, İmren; Balcıoğlu, Sevgi; Ateş, Burhan; Köytepe, Süleyman
    In this study, we investigated the effects of SiO2 nanoparticles (SiO2-NPs) (1, 10, 25, 50, and 100 mg/L) for 24 h in vitro on the motility parameters and oxidative stress markers such as total glutathione (TGSH), catalase (CAT), and malondialdehyde (MDA) of rainbow trout, Oncorhynchus mykiss sperm cells. Therefore, SiO2-NPs were synthesized with sol-gel reaction from tetraethoxy orthosilicate (TEOS). The prepared nanoparticle structures were characterized for chemical structure, morphology and thermal behavior employing Fourier transform infrared spectroscopy, X-ray spectroscopy, scanning electron micrograph, and thermal analysis (DTA/TGA/DSC) techniques. After exposure, there was statistically significant (p
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    Melatonin protects sperm cells of Capoeta trutta from toxicity of titanium dioxide nanoparticles
    (Springer, 2020) Özgür, Mustafa Erkan; Ulu, Ahmet; Noma, Samir Abbas Ali; Özcan, İmren; Balcıoğlu, Sevgi; Ateş, Burhan; Köytepe, Süleyman
    In this study, it was aimed to determine the protective effects of melatonin (0.01, 0.1, and 1 mM) against 10 mg/L titanium dioxide nanoparticles (TiO2-NPs) on kinematic and oxidative indices in the sperm cells of Capoeta trutta. Therefore, TiO2 nanoparticles were synthesized primarily within the scope of the study. The synthesized nanoparticles were characterized by structurally different techniques. Then, melatonin and TiO2 were applied to Capoeta trutta sperm cells by in vitro. According to our data, all doses of melatonin showed protective effects on all velocities of sperm cells such as the straight line velocity (VSL), the curvilinear velocity (VCL), and the angular path velocity (VAP) against TiO2-NPs, while 0.1 and 1 mM doses of melatonin improved the VSL value. Although TiO2-NPs increased total glutathione (tGSH), malondialdehyde (MDA) lipid peroxidation, and superoxide dismutase (SOD) compared to the control group, there were positive treatment effects for all doses of melatonin on antioxidant capacity of sperm cells. At the end of this research, it is suggested that over 0.1 mM dose of melatonin improves the velocity of sperm cells and it plays a protective role against the toxic effects of TiO2-NPs.
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    Tire Rubber Based Microplastic Particles Cause Adverse on Quality Parameters of Rainbow Trout Sperm Cells
    (Springer, 2024) Ozgur, Mustafa Erkan; Ulu, Ahmet; Sezer, Selda; Koytepe, Sueleyman; Ates, Burhan
    In the present study, we aimed to determine the parameters of oxidative stress markers, motility and kinematics of rainbow trout (Oncorhynchus mykiss) sperm cells exposed to different doses (0.001, 0.01, 0.1, 1.0, and 10 mg/L, in vitro 4 h) of tire rubber based microplastic particles (TRMP-Ps) the leachates procedure of rubber pieces. First of all, TRMP-Ps were prepared by abrasion method in accordance with the literature. Structural and morphological features of TRMP-Ps were determined by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM) methods, respectively. Energy dispersive X-ray (EDX) analysis technique was used to characterize the elemental composition of TRMP-Ps. Particle size of microplastic structures was measured hydrodynamically with dynamic light scattering analysis (DLS). After exposure, the effect of TRMP-Ps was defined by the observations of kinematics and antioxidant activities in sperm cells. Our findings showed that the straight line velocity, the curvilinear velocity, the angular path velocity, and the amplitude of lateral displacement of sperm cells decreased. Moreover, while the level of superoxide dismutase decreased dose-dependently against the toxicity of TRMP-Ps, no significant change was observed in the levels of malondialdehyde and total glutathione. The 4-h median effective concentrations (EC50) of TRMP-Ps based on mobility parameters of sperm ranged from 0.31 mg/L for reduced straight line velocity of sperm cells to 0.51 mg/L for reduced amplitude of lateral displacement of the spermatozoa head. Therefore, we concluded that TRMP-Ps can be a risk for the reproduction cycle of fish in aquatic environments.
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    The toxicity assessment of iron oxide (Fe3O4) nanoparticles on physical and biochemical quality of rainbow trout spermatozoon
    (Multidisciplinary Digital Publishing Institute (MDPI), 2018) Özgür, Mustafa Erkan; Ulu, Ahmet; Balcıoğlu, Sevgi; Özcan, İmren; Köytepe, Süleyman; Ateş, Burhan
    The aim of this study was to evaluate the in vitro effect of different doses (50, 100, 200, 400, and 800 mg/L) of Fe3O4 nanoparticles (NPs) at 4 degrees C for 24 h on the kinematics of rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) spermatozoon. Firstly, Fe3O4 NPs were prepared at about 30 nm from Iron (III) chloride, Iron (II) chloride, and NH3 via a co-precipitation synthesis technique. Then, the prepared Fe3O4 NPs were characterized by different instrumental techniques for their chemical structure, purity, morphology, surface properties, and thermal behavior. The size, microstructure, and morphology of the prepared Fe3O4 NPs were studied by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) spectroscopy, and scanning electron microscopy (SEM) equipped with an energy-dispersive X-ray spectrometer (EDS). The thermal properties of the Fe3O4 NPs were determined with thermogravimetric analysis (TGA), differential thermal analysis (DTA), and differential scanning calorimeter (DSC) analysis techniques. According to our results, there were statistically significant (p < 0.05) decreases in the velocities of spermatozoon after treatment with 400 mg/L Fe3O4 NPs. The superoxide dismutase (SOD) and catalase (CAT) activities were significant (p < 0.05) decrease after 100 mg/L in after exposure to Fe3O4 NPs in 24 h. As the doses of Fe3O4 NPs increases, the level of malondialdehyde (MDA) and total glutathione (tGSH) significantly (p < 0.05) increased at doses of 400 and 800 mg/L.