Ahmet Harmankaya

1,2,4-Triazole derivatives are widely investigated as bioactive heterocyclic compounds with diverse biological properties; however, their potential effects on avian embryonic development remain insufficiently characterized. This study aimed to synthesize selected Mannich-type 1,2,4-triazol-5-one derivatives and evaluate their in vitro biological activities, predicted enzyme interactions, and in ovo hatchability outcomes in broiler embryos. Three derivatives (3a–3c) were synthesized and structurally characterized using Fourier-transform infrared (FT-IR), proton nuclear magnetic resonance (¹H-NMR), and carbon-13 nuclear magnetic resonance (¹³C-NMR) spectroscopy. Their reducing capacity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging activity, metal-chelating capacity, and antimicrobial activity were evaluated. Molecular docking analyses were performed against carbonic anhydrase II and catalase, using acetazolamide and 3-amino-1,2,4-triazole as reference inhibitors, respectively. For the in ovo assessment, fertilized Ross 308 eggs were allocated to non-injected control, vehicle control, and compound-treated groups. Compounds 3a, 3b, and 3c were administered on incubation day 17 at 20, 10, and 5 mg/egg, respectively, as literature-supported, compound-specific exploratory exposure levels. The compounds exhibited weak reducing capacity, negligible DPPH radical-scavenging activity, pronounced metal-chelating capacity, and selective antimicrobial activity against several bacterial strains, whereas no inhibition was observed against Escherichia coli. Docking analysis predicted favorable interactions with both enzyme targets, with compound 3c showing the most favorable binding energies. Baseline egg weights were comparable among groups, indicating that initial egg weight was unlikely to influence hatchability outcomes. Complete hatch failure occurred in all compound-treated groups, whereas hatchability was observed in the control groups. These findings suggest that the tested derivatives may adversely affect embryonic development under the applied in ovo conditions. Their pronounced metal-chelating capacity, together with the predicted interactions with carbonic anhydrase II and catalase, provides a plausible mechanistic framework for interpreting the observed embryonic outcomes. The molecular docking results complement the experimental findings and provide supportive in silico evidence for these potential interactions. These findings contribute to the limited literature on the in ovo evaluation of synthetic Mannich-type 1,2,4-triazol-5-one derivatives and provide preliminary evidence regarding their embryotoxic potential. Further dose-dependent, mechanistic, histopathological, and enzyme-based studies are required to clarify the biological basis of the observed effects and to guide future evaluation of these compounds in in ovo, biomedical, and veterinary applications.

The purpose of this study was the development of a sensitive quartz crystal microbalance sensor based on a sulfur-doped reduced graphene oxide nanomaterial and molecularly imprinting polymer for thiophanate-methyl determination in milk samples. For this aim, the sulfur-doped reduced graphene oxide nanomaterial was firstly prepared by using a facile Hummers method with a high product yield. Then, a thiophanate-methyl-imprinted quartz crystal microbalance chip based on sulfur-doped reduced graphene oxide was accomplished by UV polymerization by the mixture including N,N'-azobisisobutyronitrile as an initiator, ethylene glycol dimethacrylate as a cross-linker, and methacryloylamidoglutamic acid as a monomer. The spectroscopic and microscopic methods were applied to confirm the presence of the nanocomposite and the reliability of the sensor preparation procedure. As a result, the prepared quartz crystal microbalance sensor exhibited linearity in the range 1.0 × 10^-9-1.0 × 10^-8 M with a detection limit of 3.3 × 10^-10 M in milk samples. A quartz crystal microbalance technique with high sensitivity, selectivity, repeatability, reusability, and reproducibility was prepared for thiophanate-methyl determination in this study.

In this work, a new surface plasmon resonance (SPR) sensor based on sulphur-doped titanium dioxide (S-TiO₂) nanostructures and molecularly imprinted polymer (MIP) was presented for thiram (THI) determination in milk samples. Firstly, the S-TiO₂ nanomaterial with a high product yield was prepared by using a facile sol-gel hydrolysis technique with a high product yield. After that, UV polymerization was carried out for the preparation of the THI-imprinted SPR chip based on S-TiO₂ using a mixture including ethylene glycol dimethacrylate (EGDMA) as the cross-linker, N,N′-azobisisobutyronitrile (AIBN) as the initiator, and methacryloylamidoglutamicacid (MAGA) as the monomer. The reliability of the sensor preparation procedure has been successfully proven by characterization studies of the prepared nanomaterials and SPR chip surfaces through spectroscopic, microscopic, and electrochemical methods. As a result, the prepared SPR sensor showed linearity in the range of 1.0 × 10⁻⁹–1.0 × 10⁻⁷ M with a detection limit (LOD) of 3.3 × 10⁻¹⁰ M in the real samples, and a sensor technique for THI determination with high sensitivity, repeatability, and selectivity can be included in the literature.

This study evaluated the effects of extracts prepared using two different methods (decoction extraction and, Soxhlet ethyl acetate/hexane extraction) from Inula viscosa on H₂O₂-induced oxidative stress and wound healing model in mouse L929 fibroblast cells. The cytotoxic effect started to disappear statistically (p < 0.05) at concentrations of Soxhlet ethyl acetate/hexane extracts (SoxEHEs) in and below 0.1 mg/mL, while the same effect was observed at concentrations of decoction extracts (DEs) in and below 0.2 mg/mL. Therefore, 0.2 and 0.02 mg/mL concentrations of DE, and 0.1 and 0.01 mg/mL concentrations of SoxEHEs were used. While cell migration was positively affected in all concentrations of the research, statistically significant results (p < 0.05) were obtained from 0.2 mg/mL of DE and 0.1 mg/mL of SoxEHE extracts. Malondialdehyde (MDA) levels were found to be statistically (p < 0.05) decreased, but COL1A1 levels were higher in cell lines treated with oxidative stress + extract than in the cell line treated only with H₂O₂, and reduced glutathione (GSH) levels were higher in cell lines only treated only with extract than in oxidative stress-induced cell lines. Consequently, it has been observed that the extracts have positive effects on migration and oxidative stress. Therefore, I. viscosa may serve as a new therapeutic agent for wound healing.