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Phytochemical profile and bioactive properties of sage ( Salvia fruticosa ) and thyme ( Thymus vulgaris ) extracts
(Informa UK Limited, 2025-03-19) Kübra Aslan; Emre Erden Kopar; Kader Kelle; Hasan Karageçili; Mustafa Abdullah Yilmaz; Oguz Cakir; Saleh Alwasel; Ilhami Gulcin
We examined the phytochemical content, antioxidant, antimicrobial, anticholinergic, antidiabetic, and antiglaucoma properties of ethanol and water extracts from Salvia fruticosa (SF) and Thymus vulgaris (TV). Extracts were analyzed using four antioxidant assays, while the enzyme inhibition was tested against alpha-amylase, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and human carbonic anhydrase II (hCA II). Antimicrobial activity was evaluated against pan-resistant bacterial strains. LC-MS/MS identified rosmarinic acid as the major compound (27.61 and 34.35 mg/L in TV and SF, respectively). Ethanolic extracts had higher phenolic content (181.0 +/- 7.86 and 107.0 +/- 5.78 mu g GAE/mg for SF and TV, respectively). SF showed stronger metal-reducing capacity, while TV had superior radical scavenging ability, judging by the IC50 values (13.68 +/- 1.18 mu g/mL), defined as the concentration that reduces 50% of the enzyme activity. The highest inhibition was observed for hCA II (SF ethanolic extract, IC50 14.51 +/- 4.07 mu g/mL), AChE (SF aqueous extract, IC50 16.51 +/- 3.77 mu g/mL), and BChE (TV aqueous extract, IC50 10.60 +/- 4.93 mu g/mL). SF ethanolic extract inhibited the growth of Staphylococcus aureus and Enterococcus faecalis (11 mm at 60 mu g/mL). These findings highlight SF and TV as potential sources of natural antioxidants, enzyme inhibitors, and antimicrobials for pharmaceutical and food formulations.
Unlocking the Potential of Technology in Nursing Skills Education: A Randomized Controlled Trial
(Ataturk Universitesi, 2025-03-07) Zehra Göçmen Baykara; Nurcan Çalışkan; Deniz Ozturk; Ayişe Karadağ; Evrim Sarıtaş; Gulcan Eyuboglu; Sinan Aydoğan; Nevin Doğan; Ceyda Su Gündüz
Objective: This study aimed to determine the effect of illustrated checklists and web-access videos on nursing students' basic nursing knowledge levels and psychomotor skills. Methods: This single-blind, randomized controlled trial was conducted with 205 first-year nursing students registered in a Fundamentals of Nursing course. The students were stratified by gender and randomly assigned to the experimental and control groups using simple randomization. All students participated in theoretical lectures, demonstrations, and laboratory practices. The Intervention Group's laboratory practices were supported by illustrated checklists and web-access skill videos. Results: The intervention group's objective structured clinical exams and knowledge test scores were significantly higher than the control group's (P < .05). In total, 95.4% of the students stated that watching videos facilitated learning. Conclusion: The study found that illustrated checklists and web-accessible skill videos improved students' knowledge and skills and that the skill videos facilitated learning, increased motivation, and enhanced clinical preparation. The widespread use of illustrated checklists and web-access skill videos in nursing skills education is suggested.
Online Education on Sustainable Nutrition Affects Women's Sustainable Eating Behavior and Anthropometric Measures
(Wiley, 2025-03-12) Gülsüm Şahin‐Bodur; Esra Tunçer; Emre Duman; Selen Yilmaz; Alev Keser
Objective: To determine the effect of online sustainable nutrition education (SNE) on sustainable eating behaviors and anthropometric measurements in women. Design: In the research, a pretest-posttest quasi-experimental design was used for groups that were subjected to two different trainings. Sample: In the education group, 34 and in the control group, 51 women that between the ages of 19-50 years from six Women's Education and Culture Centers of Ankara Altındağ Municipality. Intervention: After the pretest, the Healthy Nutrition Education (HNE) group received one session of education on "healthy eating" in the second week of the study, while the SNE group received one session of education on "healthy eating" in the second week and "sustainable nutrition" in the third and fourth weeks. Participants were given SNE and its effectiveness was evaluated after 10 weeks. Results: At the end of 10 weeks, body fat percentage decreased significantly from 35.0 ± 6.7 to 33.7 ± 6.8 in the SNE group (p = 0.007). In addition, muscle mass (kg) increased significantly from 43.4[6] to 44.7[5.2] in the SNE group (p = 0.001). When covariance analysis was performed by correcting for body mass index, the group factor had an effect on body fat percentage and muscle mass (p = 0.035 and p = 0.007, respectively). After 10 weeks, the SNE group had a higher Sustainable and Healthy Eating Behaviors Scale mean score (p = 0.013), seasonal foods and avoiding food waste (p = 0.044), animal health (p = 0.003), reducing meat consumption (p = 0.022), healthy and balanced nutrition (p = 0.031), and low fat (p < 0.001) scores compared to HNE group. Conclusions: The dissemination of structured nutrition education for women is important for individuals and, thus, society to acquire and maintain positive eating practices that have an impact on physical health.
Stable electrode material for use in supercapacitor with iodine doping after sulfonation of mesoporous activated carbon particles based on microalgae biomass
(2025-01-01) Levent, Abdulkadir; Saka, Cafer
Developing appropriate electrode materials is crucial for achieving supercapacitors with high power output and extended cycle life. Among these, biomass-derived carbon electrodes hold a prominent position in supercapacitor applications. However, these electrodes need to be modified by appropriate methods to increase their performance. In this study, sulphur and iodine heteroatom functionalization was performed using a hydrothermal method on activated carbon (SPAC) derived from a microalgae precursor through potassium hydroxide activation, resulting in iodine- and sulphur-doped SPAC (iodine@S-doped SPAC). Characterization was carried out with Scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction analysis (XRD), energy-dispersive X-ray spectroscopy (EDS), and nitrogen adsorption/desorption analyses. The electrochemical properties of the resulting composite material as a supercapacitor were examined. A specific capacitance of 208.95 F/g was achieved with the iodine@S-doped SPAC supercapacitor. The maximum energy density and power density of the supercapacitor, derived from the iodine@S-doped SPAC sample, were calculated as 5.11 Wh/kg and 2000 W/kg, respectively. Additionally, the coulombic efficiency of this supercapacitor was calculated to be 87.57% at a current density of 0.06 A/g. It also exhibited a capacity retention of up to 89.72% over 1000 cycles.
Comprehensive experimental and computational analysis of endemic Allium tuncelianum: Phytochemical profiling, antimicrobial activity, and In silico studies for potential therapeutic applications
(Elsevier BV, 2025-05) Oğuzhan Özdemir; Nurten Yılmaz; Ahmad Badreddin Musatat; Tuna Demirci; Servet Çete; Emrah Yerlikaya; Mustafa Oğuzhan Kaya
Allium tuncelianum (TG), an endemic garlic species from Tunceli, Turkey, was investigated using a multidisciplinary approach combining experimental and computational methods. Density Functional Theory (DFT) calculations with B3LYP/def2-SVP/def2-TZVP basis sets were employed to analyze electronic properties, reactivity, and stability under gas and ethanol conditions. Headspace/GC-MS identified 10 major components, with diallyl disulfide (48.03 %) and 1-propene (20.72 %) as predominant. Antimicrobial assays revealed potent activity against MRSA, Salmonella paratyphi A, and E. coli, with MIC values as low as 0.063 mg/mL. Antioxidant capacity, evaluated via DPPH, metal chelating, and FRAP assays, showed promising results, with the water extract exhibiting the highest activity (1.74 mg BHT equivalent/mL). DFT and molecular docking studies highlighted key compounds as potential inhibitors of E. coli Gyrase B, with binding energies of -5.68 and -6.07 kcal/mol. ADME predictions indicated favorable drug-like properties, though some compounds showed potential CYP450 interactions and toxicity. This study provides a comprehensive understanding of TG's biochemical profile and therapeutic potential, offering insights for future research and optimization.
Utilisation of Cu2O/CuO@N, O doped catalysts on activated carbon particles derived from biological wastes for highly active hydrogen production with sodium borohydride methanolysis
(Elsevier BV, 2025-05) Cafer Saka
Despite the significant advantages of hydrogen (H2) production via sodium borohydride (SB, NaBH4) methanolysis, it is important to further develop this reaction with more efficient and cost-effective catalysts. Here, in the first stage, pomegranate peels, which are widely consumed in the world and Turkey, were evaluated in the production of activated carbon as biowaste (PPAC). In the second stage, the obtained PPAC was hydrothermally treated with nitric acid for O atom doping on the surface (O-doped PAC). In the third stage, Cu2O/CuO and N atoms particles were doped on the O-doped PPAC by hydrothermal method (Cu2O/CuO@N, O-doped PPAC). These Cu2O/CuO@N, O doped PPAC nanoparticles were used for the first time for effective H2 production from NaBH4 methanolysis(SB/ H2P). The active regions obtained based on Cu2O, CuO, N, and O particles on the carbon support exhibited HGR values of 4775 and 40622 mL/min/gcat for PPAC and Cu2O/CuO@N, O-doped PPAC, respectively. A significant increase of approximately eight times was achieved in the hydrogen generation rate (HGR) value. The XPS, EDS, and FTIR analyses successfully confirmed both CuO particles and O, N atoms doping into the PPAC structure. The activation energy for this reaction was 29.45 kJ/mol.
Green-synthesized ZrFeO nanoparticles as efficient cathode materials in PEM fuel cells
(Elsevier BV, 2025-01) Suna Tarhan; Arzu Ekinci; Orhan Baytar; Abdurrahman Akdag; Ömer Şahin
This study explores the application of ZrFeO nanoparticles, synthesized from fig leaf extract through a green synthesis method, as cathode materials for PEM fuel cells. The nanoparticles, doped with FeO and varying Zr ratios, were combined with Pt metal and characterized using XRD, SEM, EDX, and TEM to analyze their structural and morphological properties. The particle sizes for FeO and Zr-doped FeO were determined to be 2 nm and 2.5 nm, respectively. The electrochemical active surface areas of the catalysts—Pt-FeO/C and Zr-doped variants (PtFeO/C-1 wt%Zr, PtFeO/C-5 wt%Zr, and PtFeO/C-10 wt%Zr)—were measured as 97, 154, 138, and 119 m2/gPt, respectively, demonstrating a significant enhancement in surface area with the incorporation of Zr at optimal doping levels. Catalyst retention after 250 cycles was 29% for Pt–FeO/C, 60% for 1 wt% Zr-doped Pt–ZrFeO/C, 93% for 5 wt% Zr-doped Pt–ZrFeO, and 71% for 10 wt% Zr-doped Pt–ZrFeO. Performance testing at 70 °C revealed a hierarchy of catalytic activity: Pt–ZrFeO/C > Pt–FeO/C > Pt/C. The findings highlight the potential of green-synthesized ZrFeO nanoparticles as effective support materials for cathode catalysts, offering improved performance in PEM fuel cells while markedly reducing platinum dependency. This innovative approach integrates environmental sustainability with technological progress in fuel cell applications.
Predictors of Breastfeeding Success in Postpartum Period: Delivery Type, Postpartum Support, and Postpartum Depression
(Ataturk Universitesi, 2024-12-23) Ayşegül Kılıçlı; Sidar Gül
This study aimed to investigate the association between delivery type, postpartum support need and postpartum depression on breastfeeding success in the first postpartum month. Methods: This study, conducted between August 8, 2022 and August 31, 2023, was comparative, prospective and cross‐sectional. Sample consisted of 300 women (150 vaginal, 150 cesarean section). Data were collected using Descriptive Information Form, Postpartum Support Questionnaire, Edinburgh Postpartum Depression Scale, and Bristol Breastfeeding Assessment Tool. Multiple linear regression was used to identify the predictors of breastfeeding success. Results: Those who did not received sufficient support rate was 50.7%, the presence of postpartum depression was 54.0%, and the mean breastfeeding success score was 6.4±0.9 which was moderate. Cesarean delivery (β=‐0.149, p<.01), increased need for postpartum support (β=‐0.203, p<.01) and postpartum depression (β=0.261, p<.01) were significant predictors which were explaining 21.0% of total variance in breastfeeding success. The breastfeeding success of cesarean section mothers who did not have postpartum depression but received inadequate support decreased by 20.3% compared to vaginal birth mothers. Mothers who gave birth by caesarean section, did not receive postpartum support and were at risk of postpartum depression had the lowest breastfeeding success. Conclusion: Cesarean section, postpartum support, and postpartum depression are factors that significantly affect breastfeeding success. Therefore, breastfeeding counselling services for mothers in the postpartum care process should be planned and implemented individually to address mode of delivery, need for postpartum support and postpartum depression.
The validity and reliability study of the Turkish version of the Ethical Awareness Scale
(Informa UK Limited, 2024-12-28) Gülcan Eyüboğlu; Nevin Doğan; Arnel Böke Kiliçli; Zehra Göçmen Baykara; Aimee Milliken
The heightened focus on patient safety and the quality of nursing care in intensive care units underscores the necessity for reliable tools to evaluate nurses’ ethical awareness. This study was aimed to evaluate the psychometric properties of the Turkish version of the Ethical Awareness Scale in a sample of intensive care nurses. Data were collected from 249 intensive care nurses in Türkiye using the Turkish version of the 18-item Ethical Awareness Scale. The data were then analyzed using Rasch analysis. The Turkish version of the Ethical Awareness Scale demonstrated unidimensionality and an acceptable fit for the Rasch model. The person reliability and item reliability were 0.63 and 0.92, respectively. The Turkish version of the Ethical Awareness Scale was found to be a psychometrically valid and reliable instrument for measuring the ethical awareness levels of intensive care nurses.
Utilisation of green nitrogen-doped biomass-based hierarchical porous activated carbon particles for enhancement of electrochemical energy storage performance
(Elsevier BV, 2025-02) İlyas Genel; Yavuz Yardım; Cafer Saka
Activated carbon particles were obtained from rosehip wood-based carbon precursor by chemical activation with potassium hydroxide (RHAC). After this pyrolysis process, nitrogen-doped hierarchical porous carbon was prepared by ammonia activation (N-doped RHAC). The prepared carbonaceous materials were designed as an electrode for a supercapacitor. Standard electrochemical analyses were performed. The specific capacitance (Cs) of RHAC/GCE was determined to be 25 F/g at 2.5 mV/s and 23 F/g at 0.2 A/g. In contrast, the N-doped RHAC/GCE demonstrated significantly higher Cs values of 119 F/g at 2.5 mV/s and 121 F/g at 0.2 A/g. According to CV and GCD measurements, the N-doped RHAC material exhibited approximately a fivefold increase in specific capacitance compared to the RHAC-based electrode. A specific capacitance retention rate of 94.6 % was obtained after 1000 cycles at a current density of 1.6 A/g. The surface properties and characteristics of the obtained materials were carried out by SEM, nitrogen adsorption, Raman, FTIR, EDS and XPS analyses. EDS and XPS analyses showed that N atom doping was successful. This study suggests that rosehip tree biomass-based N atom doped carbon material is suitable for supercapacitors as an electrode.
HEMOGLOBİN VE NİTRİT BAĞIMLI TİROZİN NİTRASYONU
(2017) Karageçili, Hasan; Kılınç, Kamer
Nitric oxide (NO) reacts with oxyhemoglobin or oxymyoglobin resulting in the generation of nitrate and metHb or metMb. Unlike the case of nitrate, nitrite is not an innocuous end product of NO oxidation. Hemoproteins including several peroxidases are shown to cause nitrite oxidation in the presence of H2O2. Reactive nitrogen oxides generated in hemoprotein-catalyzed nitrite oxidation are held responsible for bactericidal and cytotoxic actions of nitrite. In this study with Griess method the oxidation of nitrite to nitrate in the presence of H2O2 by hemoglobin were searched. No nitrite oxidation was observed either in the absence of H2O2 or hemoglobin, showing that the reactive species causing nitrite oxidation is a oxoferryl complex (compound I) formed from the reaction of H2O2 with hemoglobin. In this study, similar to peroxidase enzymes, we found that hemoglobin causes the nitration of tyrosine. Hemoglobin-catalyzed tyrosine nitration was pH-dependent with the optimum pH of 6,0. Hemoglobin and H2O2 were essential components for tyrosine nitration. We have not observed any tyrosine nitration without hemoglobin even at the lowest pH studied. However during hemoglobin-catalyzed nitrite oxidation in the presence of H2O2, nitrating species are produced. We conclude that, by the series of reactions between hemoglobin, H2O2 and nitrite, nitrogen dioxide radical (NO2 - ) and/or peroxynitrite like reactive species are produced, and these species are responsible for tyrosine nitration.
Carbonic Anyhdrase Enzyme From The Siirt Mohair Goat Liver :Purification, Characterization and Assessment of Enzyme Kinetics Against Metal Toxicity
(2017) Yerlikaya, Emrah; Karagecili, Hasan; Demirdag, Ramazan; Kaya, Mustafa Oguzhan
Because of their physiological and clinical roles, carbonic anhydrases (CAs) are the most studied enzymes. In earlier studies; CA enzymes have been purified and characterized from the tissues and erythrocytes of many organisms such as; dog, swine, sheep, chicken, bee, fish, bovine, bacteria and human. In this study, the CA enzyme has purified from Siirt Mohair Goat liver tissue with 1930.84 EU x mg-1 of specific activity, 57.28% of purification yield and 80.55 of purification folds. The purity of the purified enzyme has confirmed by SDS-PAGE. As the characterization of CA enzyme’s in Siirt Mohair Goat liver has been done; the optimum ionic strength=25 mM, the optimum pH= 8.0, the optimum temperature= 40ºC and the stable pH= 7.0 has been determined. Inhibitory effects of some metal ions have been examined on the purified CA enzyme. IC50 values of inhibiting metal ions were found as 2.24, 2.76, 2.36, 3.20, 2.55, 2.25, 3.28, 2.13, 3.10, 1.75, 2.16 and 3.50 mM for Al3+, Ni2+, Cd2+, Cu2+, Pb2+, Ba2+, Zn2+, B3+, Fe3+, Se2+, Ag+ and Co2+ respectively. As a result, CA enzyme was first purified from the
Effects of some heavy metals on the activities of carbonic anhydrase enzymes from tumorous and non-tumorous human stomach
(2015) Yerlikaya, Emrah; Demirdag, Ramazan; Kufrevioglu, Omer Irfan; Gundogdu, Cemal
In this study, in vitro effects of certain heavy metals on the human carbonic anhydrase enzyme were examined. Inhibitory effects of metal ions (Pb2+, Cu2+, Fe2+, Cr2+, Al3+, Ni2+, Mn2+, Cd2+, Zn2+, and Mg2+) were observed in tumorous and non-tumorous tissue. IC50 values were calculated for metals. The Cu2+, Zn2+, Ni2+, Cd2+ and Mg2+ IC50 values of tumorous tissue were calculated as 0.034 mM, 0.426 mM, 0.597 mM, 0.878 mM and 2.52 mM, respectively. The Cu2+, Zn2+, Ni2+, Cd2+ and Mg2+ IC50 values of non-tumorous tissue were calculated as 0.067 mM, 0.991 mM, 1.065 mM, 1.724 mM and 6.13 mM, respectively. Carbonic anhydrase activity was measured as described by Wilbur and Anderson. Hydratase activity was used to determine IC50 values. In this study, tumorous and non-tumorous human stomach tissues were selected due to the fact that among the diseases, stomach cancer has one of the highest mortality rates. Stomach cancer, a type of cancer affecting the digestive system, is a fatal disease in living systems. The effects of metals on the CA enzyme were investigated due to the extremely important role that CA enzymes play in living beings.
Inhibition Effects of Some Sulfonamides on Carbonic Anhydrase from European seabass (Dicentrachus labrax)
(2011) Erdem, Deryanur; Yerlikaya, Emrah; Ceyhun, Saltuk Bugrahan; Demirdag, Ramazan; Senturk, Murat; Erdogan, Orhan; Kufrevioglu, Omer Irfan
Alpha-carbonic anhydrase (EC: 4.2.1.1; CA) was purified from European seabass gill and liver. The purification procedure was composed of preparation of homogenate (or hemolysate) and affinity chromatography on Sepharose 4B-tyrosine-sulfanilamide. Some sulfonamides exhibited in vitro inhibitory effects on the enzyme activity. Ki constants and IC50 values for these drugs were determined by Lineweaver-Burk graphs and plotting activity % vs. [I], respectively. IC50 values of sulfanilamide, mafenide, acetazolamide, 2-amino-1,3,5-tiyadiazol-5 sulfonamide were 980 ??M, 142 ??M, 20 ??M and 34 ??M for gill carbonic anhydrase (GCA), 126 ??M, 23 ??M, 14 ??M and 2.58 ??M for liver carbonic anhydrase (LCA), respectively. Some sulfonamides exhibited much stronger inhibitory activity against GCA and LCA at low micromolar concentrations with the Ki values ranging from 0.21 to 76.0 ??M as compared with other CAs.
Purification and Characterization of a-Carbonic Anhydrase II from Sheep Liver and Examining the Inhibition Effect of Kanamycin on Enzyme Activity
(2012) Comakli, Veysel; Yerlikaya, Emrah; Demirdag, Ramazan; Kufrevioglu, Omer Irfan
Sheep carbonic anhydrase - II (SCA-II) (E.C: 4.2.1.1) was purified from sheep liver and some characteristic properties were investigated. The enzyme was purified approximate 43.1-fold with a yield of 38.6%, and a specific activity of 4000 EU/mg proteins. For the enzyme, optimum pH, optimum temperature, optimum ionic strength and stable pH were determined to be 7.5, 40 ºC, 10 mM and 8.5, respectively. The molecular weight was found 29 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Kanamycin exhibited in vitro inhibitory effect on the enzyme activity.
Purification of CA Isoenzymes from Human Cancerous Colon Tissue and Inhibitory Effects of Some Analgesics on Enzyme Activity
(2012) Demirdag, Ramazan; Yerlikaya, Emrah; Kufrevioglu, Omer Irfan; Gundogdu, Cemal
Carbonic Anhydrase (CA) is an enzyme which is responsible for the hydration of carbon dioxide to carbonic acid and it also takes places in many biological processes in the living organisms. In this study, CA isoenzymes (CA II and CA IX) together were purified 78.4 fold with a yield of 54.86 and specific activity of 106.67 by using Sepharose 4B-L-tyrosine sulfanilamide affinity chromatography. In SDS-PAGE molecular weights of CA II and CA IX were calculated as 29 kDa and 56 kDa respectively. Besides inhibitory effects of some analgesics on purified total enzyme was investigated. IC50 values were found as 0.0077, 0.025, 0.011 and 0.04 mM for dexketoprofen, pethidine, phenyramidol and tramadol respectively.
Siirt Tiftik Keçisi Böbrek Dokusundan Karbonik Anhidraz Enziminin Saflaştırılması, Karakterizasyonu ve Bazı Biyokimyasal Özelliklerinin Araştırılması
(2016) Yerlikaya, Emrah; Karagecili, Hasan; Demirdag, Ramazan; Kaya, Mustafa Oguzhan
Carbonic anhydrase (CA) (E.C:4.2.1.1) is a group of metalloenzyme containing zinc widely distributed from the simplest organisms such as bacteria to the most complex organisms such as plants and animals. CA inhibitors are some of the principal drugs used in the management of canine and feline glaucoma. In earlier studies; CA enzymes successfully have been purified and characterized from many living things such as; sheep, chicken, fish, bovine and human. In this study, the CA enzyme has purified from Siirt Mohair Goat kidney tissue with 902.9 EU x mg-1 of specific activity, 50.19% of purification yield and 83.54 of purification folds by using Sepharose-4B-L-tyrosine-sulfonamide affinity column. The purity of the purified enzyme has confirmed by SDS-PAGE. As the characterization of CA enzyme’s in Siirt Mohair Goat kidney has been done; the optimum ionic strength=25mM, the optimum pH=8.5, the optimum temperature=45ºC and the stable pH=7.0 has been determined. Inhibitory effects of Al3+, Ni2+, Cd2+, Pb2+, Ba2+, Zn2+, B3+, Fe3+, Se2+, Ag+ and Co2+ metal ions have been examined on the purified CA enzyme. Inhibition graphics have been drawn in order to find the IC50 values of metals showing inhibition.
INHIBITORY EFFECTS OF SOME PESTICIDES AND METALS ON CARBONIC ANHYDRASE PURIFIED FROM SHABUT FISH BARBUS GRYPUS ) GILL TISSUE
(2019) Yerlikaya, Emrah
Carbonic anhydrase enzyme catalyzes the reversible inter-conversion of CO2 and HCO3. The enzyme is crucial for the osmotic balance and acid–base regulation in the fish. It is well-known that gills of fish play the most important role in acid–base relevant ion transfer, the transfer of H+ and/or HCO3, for the maintenance of systemic pH. Many researches have shown that fish are the species that is the most susceptible to environmental toxins. In addition, these toxins firstly encounter the gill tissue in fish. In this study, the carbonic anhydrase enzyme was purified 198.6-folds with 58.8% yield from Shabut Fish (Barbus grypus) gill tissue by Sepharose-4B-L-tyrosine-sulfanilamide affinity column. The specific activity was determined as 2.92 EU/mg protein. The molecular weight determined by sodium dodecyl sulfate–polyacrylamide gel electrophoresis was found to be about 29.9 kDa. Inhibitory effects of some pesticides (Spinosad and Dimethoate) and metal ions (Al3+, Cu2+, Ba2+, Fe2+, Mn2+, Se2+) were examined on the purified carbonic anhydrase enzyme. Inhibition graphics were drawn in order to find the IC50 values of metals and pesticides showing inhibition. The kinetic parameters of this enzyme were determined for its esterase activity, with 4-nitrophenyl acetate as substrate.
PURIFICATION, CHARACTERIZATION OF GLUTATHIONE S-TRANSFERASE FROM THE GILL TISSUE OF LAKE VAN FISH AND INHIBITION EFFECTS OF SOME METAL IONS AND PESTICIDES
(2019) Zaric, Yakup; Yerlikaya, Emrah; Demirdag, Ramazan
Glutathione-S-Transferases (GSTs) are xenobiotic metabolizing enzymes that protect cells from toxic drugs and environmental electrophiles. Furthermore, these enzymes have effected the regulators of oxidative stress and toxicity [1]. In earlier studies; GST enzymes have been purified and characterized from many living things such as sheep, bird, fish, bacterium, bovine and human. This study proves the purification and characterization of GST enzyme (E.C. 2.5.1.18) from the Gill Tissue of Lake Van Fish by affinity chromatography. Inhibitory effects of some metal ions and pesticides on GST activity were determined with using the CDNB method under in vitro conditions. Purification degree for the purified enzyme was controlled by SDS-PAGE. Optimal pH, optimal ionic strength, optimal temperature and stable pH were determined as 7.3, 120 mM, 35°C, 8.0, respectively. Inhibitory effects of Al3+, Ba2+, B3+ and Se2- metal ions and Oxamyl, Diniconazole, Carbofuran, Tebuconazole and Atrazine pesticides have been examined on the purified GST enzyme. Inhibition graphics have been drawn in order to find the IC50 values of metals and pesticides showing inhibition from Activity % -[Inhibitor] graphs. Consequently, in vitro inhibition rank order was determined as Al3+ > Ba2+ > Se2- > B3+ for metal ions, Carbofuran > Tebuconazole > Oxamyl > Atrazine > Diniconazole for pesticides.
Purification of carbonic anhydrase-II from sheep liver and inhibitory effects of some heavy metals on enzyme activity
(2012) Demirdag, Ramazan; Yerlikaya, Emrah; Kufrevioglu, Omer Irfan
In this study; sheep carbonic anhydrase-II (SCA-II) (E.C: 4.2.1.1) was purified from sheep liver and in vitro effects of heavy metals on the enzyme was examined. SCA-II isozyme was purified with about 203 purification fold, a specific activity of 2320 EU/mg-protein and a yield of 72 by using Sepharose-4B-L tyrosine-sulfanilamide affinity gel chromatography. Purity of the SCA-II enzyme was verified by SDS-PAGE technique and subunit molecular mass of the enzyme was found as 29 kDa. In addition to this, inhibitory effects of some metal ions on the enzyme were examined. In this study, sheep liver tissue was chosen; because the liver is an organ in which metal wastes of air, water and food are collected and it is easy to obtain the liver tissue. Because of the very important duties of CA enzyme on living beings, the effect of metals on the CA enzyme was investigated.

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