https://hdl.handle.net/20.500.12809/237 2026-07-10T07:54:28Z 2026-07-10T07:54:28Z Sabudak, Temine Argon, Merve Çakır, Cansel c https://hdl.handle.net/20.500.12809/11232 2026-06-26T07:11:24Z 2026-01-01T00:00:00Z

Natural Product r esearch Alkaloid contents and biological activities of Genista lydia Boiss. Sabudak, Temine; Argon, Merve; Çakır, Cansel; c This study aimed to investigate the biological activities and alkaloid composition of Genista lydia Boiss. (syn. Genista januensis subsp. lydia) growing in the Trakya Region. The plant material was sequentially extracted using chloroform, ethyl acetate, and methanol. The alkaloid composition of the methanolic extract was analyzed by GC-MS. In addition, the extracts were evaluated for their anticholinesterase, antibacterial, tyrosinase-inhibitory, urease-inhibitory, alpha-glucosidase-inhibitory, and alpha-amylase-inhibitory activities. GC-MS analysis of the methanolic extract revealed the presence of 14 alkaloid compounds. The major constituents were identified as N-methylcytisine (60.45%), cytisine (22.24%) and anagyrine (13.55%).

2026-01-01T00:00:00Z Taş Küçükaydın, Meltem Duru, Mehmet Emin Demiray, Aydın Küçükadın, Selçuk Ceylan, Özgür https://hdl.handle.net/20.500.12809/11224 2026-06-24T13:49:10Z 2026-01-01T00:00:00Z

Sustainable Bioactive Hydrogels Engineered with Liquidambar orientalis Extracts: pH-Dependent Release Behavior and Wound Healing Potential Taş Küçükaydın, Meltem; Duru, Mehmet Emin; Demiray, Aydın; Küçükadın, Selçuk; Ceylan, Özgür Bioactive hydrogel films were developed by incorporating Liquidambar orientalis leaf extract (LOLE) and resin extract (LORE) into PVA/starch, PVA/chitosan, chitosan/gelatin, and chitosan matrices. HPLC-DAD identified myricetin as a major LOLE marker and trans-cinnamic acid as the predominant LORE compound, while SEM and FT-IR analyses supported extract incorporation and possible interactions within the hydrogel networks. The films exhibited polymer- and extract-dependent physicochemical behavior. LOLE-loaded chitosan films showed the highest swelling capacity (350%) and the highest in vitro mass loss after 14 days. Release studies demonstrated matrix-dependent and pH-dependent behavior within the tested pH range, with faster release generally observed at pH 5.5 than at pH 7.4; LOLE-loaded chitosan/gelatin films released 85.3% of the extract within 12 h at pH 5.5. LOLE-loaded hydrogels showed stronger antioxidant activity, whereas LORE-loaded films exhibited stronger antimicrobial performance against wound-associated microorganisms, reflecting their distinct phytochemical profiles. The extracts also showed antibiofilm, anti-quorum sensing, enzyme-inhibitory, and preliminary scratch wound closure activities, with no apparent cytotoxicity toward HEK-293T cells. LORE showed notable tyrosinase inhibition (IC50: 20.18 & micro;g/mL), suggesting pigmentation-related relevance. Overall, these findings support further investigation of L. orientalis-derived hydrogel films as sustainable bioactive wound dressing platforms, although mechanical, stability, and in vivo validations remain necessary.

2026-01-01T00:00:00Z Özyurt, Vasfiye Hazal Çaylayık, Nil Su Çitil, Burak Ekrem Türkiş, Fulden Cantaş Anık, Ülkü https://hdl.handle.net/20.500.12809/11220 2026-06-24T07:50:40Z 2026-01-01T00:00:00Z

A Hybrid Nanomaterial-Based Electrochemical Sensor for Melatonin Measurement in Human Saliva: A Diagnostic Tool for Anxiety Disorder Özyurt, Vasfiye Hazal; Çaylayık, Nil Su; Çitil, Burak Ekrem; Türkiş, Fulden Cantaş; Anık, Ülkü Since the diagnosis of anxiety disorder is primarily based on questionnaires, accurate identification of the disorder can be challenging. Melatonin has been identified as a potential biomarker for the detection of anxiety disorders. By targeting this biomarker, it will be possible to get more accurate results and diagnose anxiety disorder more properly. In this study, a carbon screen-printed electrode modified with multi-walled carbon nanotube-gold-platinum (MWCNT-Au-Pt) nanocomposite-based electrochemical sensor was developed for the detection of melatonin. To enhance the sensor's performance, key experimental parameters-including the amount of MWCNT-Au-Pt nanoparticle and the pH of the solution-were systematically optimized. The sensor exhibited two linear response ranges for melatonin: from 0.5 to 50 & micro;M with a limit of detection (LOD) of 0.23 & micro;M, and from 100 to 1000 & micro;M with an LOD of 2.14 & micro;M. The sensor's specificity was evaluated in the presence of potential interfering substances. It was subsequently applied successfully to the detection of melatonin in 25 real human saliva samples. As a result, the first MWCNT-Au-Pt modified electrochemical sensor for melatonin detection, which will lead to proper anxiety disorder diagnosis, was fabricated.

2026-01-01T00:00:00Z Perk, Benay Tepeli-Büyüksünetci, Yudum Anık, Ülkü https://hdl.handle.net/20.500.12809/11047 2023-10-27T06:30:59Z 2023-01-01T00:00:00Z

Copper based metal organic framework decorated with gold nanoparticles as a new electrochemical sensor material for the detection of L-Cysteine in milk samples Perk, Benay; Tepeli-Büyüksünetci, Yudum; Anık, Ülkü A facile electrochemical sensor based on carbon felt electrode (CFE) modified with gold nanoparticles decorated copper based metal organic framework (AuNPs@Cu-MOF) was achieved for the electrochemical sensing of L-Cysteine (L-Cys). For this purpose, AuNPs@Cu-MOF was synthesized and characterized. The electrochemical behaviors of L-Cys at plain and modified CFEs were investigated via cyclic voltammetry (CV). According CV results, AuNPs@Cu-MOF structure showed a catalytic effect on the oxidation of L-Cys as well as increasing the active electrode surface area by 206% compared to bare CFE. In addition, the pH effect on electrochemical determination of L-Cys at AuNPs@Cu-MOF/CFE was widely examined, and it was determined that the best oxidation peak current of L-Cys was obtained in pH 5 acetate buffer. Moreover, a linear detection range of 30–400 µM for L-Cys with a limit of detection value of 2.21 µM (n = 3) was achieved with the proposed electrochemical sensor. The developed L-Cys sensor was also applied for L-Cys detection in various milk samples and acceptable recovery values were obtained ranging from 100.05 to 108.45%.

2023-01-01T00:00:00Z