Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2025DYE REMOVAL PERFORMANCE AND BIOLOGICAL ACTIVITIES OF IRON OXIDE NANOPARTICLES SYNTHESIZED FROM Cotoneaster sp. FRUIT EXTRACT
Akar, Bülent; Baltacı, Cemalettin; Düzgün, Azer Özad; Karpuz, Omer; Karakullukçu, Volkan; Erdoğdu, Esma Gülbahar
This work aimed to study the antioxidant, antibacterial, and dye adsorption capabilities of the aqueous extract of Cotoneaster sp. fruits (CFE) and iron oxide nanoparticles (CF-FeONP) green-synthesized from the CFE. CF-FeONPs were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analyses. The antioxidant activity of CFE and CF-FeONPs was assessed through various tests, including ABTS radical scavenging activity, DPPH radical scavenging activity, iron-reducing antioxidant power (FRAP), total phenolic content (TPC), total flavonoid content (TFC), and total antioxidant content (TAC). The CF-FeONPs had superior antibacterial and antioxidant activity compared to the CFEs. Furthermore, CF-FeONPs suppressed the growth of Gram-negative bacteria such as Yersinia pseudotuberculosis ATCC 911, Escherichia coli ATCC 25922, Proteus vulgaris ATCC 13315, and Pseudomonas aeruginosa ATCC 43288, as well as by Gram-positive bacteria like Streptococcus pyogenes ATCC 19615, Staphylococcus aureus ATCC 25923. and Bacillus subtilis ATCC 6633. The microdilution medium technique was used to determine the minimum inhibitory concentration (MIC) of CFE and CF-FeONPs against these bacteria strains. The adsorption rates of CF-FeONPs exhibited variability based on the quantity of adsorbent used and the specific dye type, whereas the lowest adsorption rate was 250 mg/L. CF-FeONPs demonstrated higher adsorption capacities for malachite green (MG) dye compared to methylene blue (MB) and phenol red (PR).
- MakaleAçık Erişim2025MODELING THE KINETICS OF HYDROXYMETHYLFURFURAL (HMF) FORMATION IN POMEGRANATE SOUR PRODUCED BY DIFFERENT EVAPORATION METHODS
Erdoğdu, Esma Gülbahar; Akar, Bülent; Baltacı, Cemalettin
Pomegranate sour is a traditional functional food that is widely consumed in Türkiye. The aim of this study is to determine the most convenient evaporation method to keep the amount of HMF, a carcinogenic substance formed as a result of high temperatures in the production of pomegranate sour, at low levels. The pomegranate sours were produced using five different evaporation methods (atmospheric pressure (AP), freeze-drying (FD), open air (OA), vacuum assisted (VA) and fan assisted (FA)) and the amount of HMF formed during the process was determined. Kinetic calculations showed that VA and FA methods followed first-order reaction kinetics at 60, 70 and 80 °C, while OA, FD and AP methods followed zero-order reaction kinetics at 80, 90 and 100 °C. The mean Q10 value was 1.0006, while the activation energy (Ea) ranged from 72.56 to 126.38 kJ/mol. It was found that the amount of HMF formed varied according to the method, temperature and production time and that the reaction rates increased with increasing temperature, especially for the OA method. In addition, pH, titratable acidity, invert and total sugar content, color, Brix and browning index were analyzed and a kinetic model including all these factors was developed.