Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection

Permanent URI for this collectionhttps://hdl.handle.net/11147/7148

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  • Article
    Influence of Innovative Thawing Approaches on the Thermal and Chemical Structure Changes of Frozen Beef Liver
    (Springer, 2026) Avsar, Nazlican; Uzuner, Sibel
    Freezing effectively preserves meat quality, but the formation of ice crystals during the process can impact tenderness and functionality. Thawing is a critical step, as it can lead to physicochemical changes-such as protein oxidation and further ice crystal growth-that may reduce product quality and consumer appeal. Therefore, the thawing method plays a key role in determining the final quality of frozen meat. This study evaluated the physicochemical and structural characteristics of beef liver frozen at - 18 +/- 2 degrees C for 20 h and thawed using three methods: water immersion thawing (WIT), ultrasonic bath thawing (UBT), and air fryer thawing (AFT). No significant differences in drip loss were observed among the UBT, AFT, and WIT samples (p > 0.05). Color measurements (L*, a*, b*) were significantly higher in raw liver than in AFT and UBT samples (p < 0.05). Compared to raw liver and the WIT method, AF and UB thawing lowered the denaturation temperature, indicating reduced thermal stability. The lowest metmyoglobin (MetMb) content was found in the UBT sample (36.57 +/- 0.87%), followed by the AFT sample (41.71 +/- 1.29%), suggesting better pigment preservation with UB thawing. Highlights circle AF and UB thawing methods resulted in a lower denaturation temperature. circle UBT showed the lowest MetMb content, helping to minimize oxidation. circle UBT caused less damage to protein chains and better preserved structural stability. circle UBT preserved desirable aroma characteristics more effectively.
  • Article
    Comparative Optimization of Hot Water and Citric Acid Extraction Methods for Sericin Recovery From Silk Cocoons: In Vitro Antioxidant and Antidiabetic Activities
    (Springer, 2026) Sincar, Bahar; Ozdemir, Feyza; Bicakci, Beyza Tutku; Erdem, Cansu; Yalcin, Dilek; Alamri, Abdulhakeem S.; Bayraktar, Oguz
    Silk sericin, a hydrophilic protein derived from Bombyx mori cocoons, has attracted increasing interest due to its antioxidant, moisturizing, and enzyme-inhibitory properties. Efficient extraction is essential to preserve its biofunctional potential. In this study, sericin was extracted using hot water and 1.25% (w/v) citric acid using autoclave-based heating to achieve pressurized conditions above 100 degrees C. A Box-Behnken Response Surface Methodology (RSM) was applied to systematically evaluate the effects of extraction parameters (temperature and time) and to optimize five key response variables: yield, purity, molecular weight and polydispersity index (PDI), total antioxidant capacity (ABTS), and alpha-glucosidase inhibition activity. The results revealed that higher temperatures (125 degrees C) produced the maximum sericin yield, while moderate conditions (115 degrees C for 45 min) ensured better preservation of antioxidant and antidiabetic activities. Hot acid extraction resulted in significantly enhanced purity and enzymatic inhibition compared to hot water extraction. Sericin fractions above 7 kDa exhibited the strongest bioactivity, as reflected by lower IC50 values in both ABTS and alpha-glucosidase inhibition assays. The optimized hot water citric acid-based method yielded 24.00% sericin with 100.00% purity and an IC50 of 0.67 mg/mL for alpha-glucosidase inhibition. This study compares hot water and hot acid autoclave extractions using Box-Behnken design and evaluates their effects on sericin yield, purity, and bioactivities. Citric acid-based extraction produced higher purity and stronger alpha-glucosidase inhibition, while hot water extraction preserved antioxidant potential more effectively. These findings support the use of citric acid as an eco-friendly and scalable extraction agent and highlight the potential of sericin in biomedical and nutraceutical applications.
  • Article
    Effect of TiO2 and ZrO2 Additions on Sintering and Mechanical Properties of Dental Porcelain Material
    (Springer, 2025) Aouadja, Faycal; Toprak, Seyra; Demir, Mustafa M.; Boudchicha, Mohamed Redda
    This study investigates the influence of varying TiO2 (0-15 wt.%) and ZrO2 (15-0 wt.%) additions on the microstructure, densification, and mechanical properties of dental porcelain composites fabricated from local Algerian raw materials. The samples were produced by cold compaction and sintered at temperatures ranging from 1100 degrees C to 1250 degrees C. Advanced characterization techniques-X-ray diffraction, Fourier-transform infrared spectroscopy, and scanning electron microscopy-were employed to analyze phase evolution and microstructural morphology. The results indicated that increasing TiO2 content while decreasing ZrO2 enhanced both densification and mechanical strength. The optimal composition-15 wt.% TiO2 sintered at 1200 degrees C-achieved the highest bending strength (177 MPa) and Martens hardness (2931 MPa). TiO2 functioned as a fluxing agent, promoting grain cohesion, whereas excessive ZrO2 content led to the formation of structural defects. These findings highlight the potential of optimized formulations to meet the requirements for high-performance, biocompatible dental ceramics and support the development of sustainable porcelain using abundant natural resources.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Structural and Functional Tuning of ZIF-8 Nanoparticles Via Zinc Salt Variation and Ligand Ratio for Enhanced Drug Delivery
    (Springer, 2025) Mete, Derya; Sanli-Mohamed, Gulsah
    The clinical application of doxorubicin (DOX), a widely used chemotherapeutic agent, is limited by systemic toxicity, rapid clearance, and the development of multidrug resistance. Metal-organic frameworks (MOFs), particularly zeolitic imidazolate frameworks (ZIFs), have emerged as promising nanocarriers to overcome these limitations due to their high drug-loading capacity, pH-responsive release profiles, and favorable biocompatibility. Among them, ZIF-8 is especially attractive for its ability to selectively release drugs in acidic tumor microenvironments. However, the physicochemical and biological properties of ZIF-8 are highly sensitive to synthesis parameters, particularly the choice of zinc salt precursor and the Zn2+:ligand molar ratio. In this study, we systematically investigated the effects of four zinc salts (zinc nitrate, zinc acetate, zinc chloride, and zinc bromide) and three Zn2+:2-methylimidazole molar ratios (1:35, 1:70, and 1:200) on the synthesis, drug-loading efficiency, release behavior, and anticancer activity of DOX-loaded ZIF-8 (DOX@ZIF-8) nanoparticles. The resulting nanocarriers were characterized using scanning electron microscopy (SEM), dynamic light scattering (DLS), energy-dispersive X-ray spectroscopy (EDX), inductively coupled plasma optical emission spectroscopy (ICP-OES), thermogravimetric analysis (TGA), and Brunauer-Emmett-Teller (BET) surface area analysis. pH-responsive DOX release was evaluated under physiological (pH 7.4) and acidic (pH 5.0) conditions. Cytotoxicity was assessed in A549 lung cancer cells via the MTT assay. Additionally, in vitro time-lapse live-cell imaging and wound healing assays were conducted to evaluate intracellular drug uptake and cellular responses. Our findings highlight the critical influence of zinc salt selection and ligand ratio on the structure-property-function relationships of ZIF-8, providing valuable insights for the rational design of MOF-based nanocarriers in targeted cancer therapy.
  • Article
    Deposition of (La,Sr)CoO₃-δ and (La,Sr)₂CoO₄-δ Cathode Layers on Gadolinia-Doped Ceria by Electrospray Deposition
    (Springer, 2025) Ergen, Emre; Akkurt, Sedat
    La-, Sr-, and Co-based oxides have proven their performances in the cathode layers of intermediate temperature levels of solid oxide fuel cells (SOFC), and hence have been frequently studied. They are deposited on the electrolyte layer by chemical vapor deposition (CVD), screen printing, pulsed laser deposition (PLD), etc. The electrospray deposition (ESD) proved itself as an effective and facile method for cathode deposition. Cathode layers deposited on gadolinia-doped ceria (GDC) with the compositions of (La0.5Sr0.5)CoO3, (La0.8Sr0.2)CoO3, (La0.5Sr0.5)2CoO4, and (La0.8Sr0.2)2CoO4 are known to provide low resistance values which are critical in cell performance. In this study, ESD is used for the first time as the coating method of these compositions. Area-specific resistance (ASR) measurements made by electrochemical impedance spectroscopy (EIS) showed promising results. Particularly, the sample coated in (La0.5Sr0.5)CoO3 composition showed an ASR value of 0.11 Omega.cm2 at 700 degrees C. ESD showed the ability to control the cathode coating microstructure by controlling the spraying parameters.
  • Editorial
    Editorial: Advancing Biotechnology in Turkiye: a Dedication To All Women
    (Springer, 2025) Cadirci, Bilge Hilal; Buyukkileci, Ali Oguz; Binay, Baris
  • Article
    Citation - WoS: 3
    Citation - Scopus: 3
    Hybrid Silica Aerogels From Bridged Silicon Alkoxides: Ultralow Thermal Conductivity for Low-Temperature Applications
    (Springer, 2025) Abebe, A. M.; Biesuz, M.; Vakifahmetoglu, C.; Cassetta, M.; Soraru, G. D.
    Hybrid silica aerogels are promising materials for thermal insulation applications. Highly porous aerogels were synthesized from bridged bis(triethoxysilyl)methane BTEM and triethoxysilane TREOS silicon alkoxides via the sol-gel process. The carbon content in the hybrid aerogels decreased with increasing amounts of TREOS. Crack-free monolith aerogels were synthesized through supercritical drying, which is crucial for thermal and optical investigations. The aerogels are characterized by high BET surface areas ranging from 700 to 1400 m(2)/g, pore volumes between 2.0 and 10.5 cm(3)/g, and a maximum porosity of 95%. The thermal conductivity of the aerogels at room temperature was measured via a hot disk apparatus. The materials exhibited ultralow thermal conductivity, reaching a minimum value of 15 mW/mK. This value ranks among the lowest reported values for silica-based aerogels in the literature. Optical transmittance measurements indicated high transparency, exceeding 80% in the visible region. Therefore, these exceptional properties of low density, high optical transparency, and low thermal conductivity make these materials promising candidates for transparent insulation applications.
  • Article
    Citation - Scopus: 1
    Investigating Early-Stage Mineralization Behavior and Bioactivity of Acid-Free Bioactive Glass 45s5 With Enhanced Dissolution Kinetics
    (Springer, 2025) Tuncer, Melisa; Yucesoy, Deniz T.; Karakus, Ceyda Oksel
    Nanostructured bioactive glass (BG) was synthesized through an acid-free sol-gel route (bioglass-AF) and the conventional acid-catalyst sol-gel process (bioglass-AC). The aim here is to eliminate the risk of residual acidic components in the BG while enhancing its functionality through nano-scale propduction. Scanning electron microscopy revealed the presence of highly porous structures and dense agglomerates composed of particles with a mean diameter of 45 nm in both samples. Bioglass-AC and bioglass-AF had specific surface areas of 1.48 m(2)/g and 2.73 m(2)/g, respectively, with an average pore size of similar to 5 nm. Faster mineralization kinetics were evident in bioglass-AF, compared to bioglass-AC, in Hepes-buffered salt solution. Following 14 days of immersion in artificial saliva, bioglass-AC and bioglass-AF lost 16% and 20% of their initial weight, respectively, confirming their bioactivity. None of the synthesized BGs stimulated cell growth up to 24 h but longer exposure to moderate concentrations (1.25 and 2.5 mg/mL) of bioglass-AF significantly enhanced cell viability, reaching 170% at 48 h. Overall, the comparative in vitro investigations proved that nano-structured 45S5 bioglass powders with improved mineralization and dissolution kinetics can be produced with an acid-free route, eliminating the risk of residual acidic components in the final product.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Imbalance in Redox Homeostasis Is Associated With Neurodegeneration in the Murine Model of Tay-Sachs Disease
    (Springer, 2025) Basirli, Hande; Ates, Nurselin; Seyrantepe, Volkan
    BackgroundTay-Sachs disease is a neurodegenerative disorder characterized by a build-up of GM2 ganglioside in the brain, which results in progressive central nervous system dysfunction. Our group recently generated Hexa-/-Neu3-/- mice, a murine model with neuropathological abnormalities similar to the infantile form of Tay-Sachs disease. Previously, we reported progressive neurodegeneration with neuronal loss in the brain sections of Hexa-/-Neu3-/- mice. However, the relationship between the severity of neurodegeneration and the imbalance in redox homeostasis was not yet clarified in Hexa-/-Neu3-/- mice. Here, we evaluated whether neurodegeneration is associated with oxidative stress in the tissues and cells of Hexa-/-Neu3-/- mice and neuroglia cells from Tay-Sachs patients.Methods and resultsCell death and oxidative stress-related markers were evaluated in four brain regions and fibroblasts of 5-month-old WT, Hexa-/-, Neu3-/-, and Hexa-/-Neu3-/- mice and human neuroglia cells using Western blot, RT-PCR, and immunohistochemistry analyses. We further analyzed oxidative stress levels in the samples using flow cytometry analyses. We discovered neuronal death, alterations in intracellular ROS levels, and damaging effects of oxidative stress, especially in the cerebellum and fibroblasts of Hexa-/-Neu3-/- mice.ConclusionsOur results showed that alteration in redox homeostasis might be related to neurodegeneration in the murine model of Tay-Sachs Disease. These findings suggest that targeting the altered redox balance and increased oxidative stress might be a rational therapeutic approach for alleviating neurodegeneration and treating Tay-Sachs disease.
  • Article
    Citation - WoS: 1
    Citation - Scopus: 1
    Euler–Euler Numerical Model for Transport Phenomena Modeling in a Natural Circulation Loop Operated by Nanofluids
    (Springer, 2025) Kamenik, B.; Vovk, N.; Elcioglu, E.B.; Sezgin, F.; Ozyurt, E.; Karadeniz, Z.H.; Ravnik, J.
    This paper explores a computational approach to model multiphase heat transfer and fluid flow in a natural circulation loop utilizing nanofluids. We propose and implement an Euler–Euler framework in a CFD environment, incorporating an innovative boundary condition to preserve mass conservation during thermophoretic particle flux. The model’s accuracy is verified through a one-dimensional example, by comparing results against both an Euler–Lagrange model and an in-house finite volume solution. Experimental validation is conducted with aluminum oxide nanofluids at varying nanoparticle concentrations. We prepared the nanofluids and measured their thermophysical properties up to 60∘C. We assess the thermal performance of the nanofluid in natural circulation loop at different heating powers via experiment and numerical simulations. The findings reveal that the heat transfer enhancement offered by the nanofluid is modest, with minimal differences observed between the proposed Euler–Euler approach and a simpler single-phase model. The results underscore that while the Euler–Euler model offers detailed particle–fluid interactions, its practical thermal advantage is limited in this context. © The Author(s) 2025.