Sürdürülebilir Kalkınma Amaçları
Yazarlar
Yayınlar
- MakaleAçık Erişim2023The Comparison with Commercial Antioxidants, Effects on Colour, and Sensory Properties of Green Tea Powder in Butter
Çakmakçı, Songül; Gülçin, İlhami; Gündoğdu, Engin; Ertem Öztekin, Hatice; Taslimi, Parham
Oxidation is one of the most important factors limiting shelf life and is a major deterioration process affecting both the sensory and nutritional quality of food. The high oxidation stability of lipids, which can be improved by the addition of antioxidants, is important for health protection, food quality, and economic reasons. In recent years, research on plant-derived antioxidants for use in human health and food has steadily increased. The aim of this study was to compare the antioxidant effects of green tea powder (GTP) in butter with those of commercial antioxidants (BHA, BHT, α-tocopherol, and Trolox). In addition, the effects on colour, sensory, gross physicochemical properties, and β-carotene content were investigated in butter. After the separation of butter into five pieces, the first part was chosen as the control sample without GTP; the second part has 100 mg/kg of BHT added to it; and the third, fourth, and fifth parts had 1, 2, and 3% of GTP added in the samples. They were stored at 4 ± 1 °C. Analysis was performed at intervals of 15 days. According to the iron reduction, CUPRAC and FRAP methods were performed, and parallel results were observed. Using the radical elimination methods (ABTS, DPPH•, and DMPD•+), IC50 values were calculated for the samples. According to the IC50 values, the GTP-containing samples were good antioxidants. The total phenolic andf β-carotene contents increased as the GTP addition increased. The addition of GTP had an antioxidant capacity equal to or higher than that of the BHT-added sample. For the production of a sensory-pleasing, greenish-coloured, new functional butter, the 1% GTP addition showed the most positive results.
- MakaleAçık Erişim2014Oxidation of cyanobenzocycloheptatrienes: Synthesis, photooxygenation reaction and carbonic anhydrase isoenzymes inhibition properties of some new benzotropone derivatives
Güney, Murat; Coskun, Ahmet; Topal, Fevzi; Dastan, Arif; Gülçin, Ilhami; Supuran, Claudiu T.
The oxidation of some cyanocycloheptatrienes with CrO3 and pyridine was investigated and a few new nitrile functionalised benzotropone derivatives were obtained. Photooxygenation reaction of these products was also studied. The structures of the formed products were determined on the basis of NMR spectroscopy and the formation mechanism of unusual products was discussed. Human carbonic anhydrase isoenzymes I, and II (hCA I and hCA II) inhibition properties of nitrile functionalized new benzotropone derivatives were also studied. Both CA isozymes were inhibited in the low micromolar range by these nitrile functionalized benzotropone analogues. The newly synthesized benzotropone derivatives showed inhibition constants in the sub-micromolar range (2.51-4.06 mu M). The best hCA I inhibition was observed in 5H-benzocycloheptene-7-carbonitrile (K-1: 2.88 +/- 0.86 mu M). On the other hand, 5-oxo-5H-benzocycloheptatriene-7-carbonitrile showed the powerful inhibitory effect against hCA II (K-i: 2.51 +/- 0.34 mu M). (C) 2014 Elsevier Ltd. All rights reserved.
- MakaleAçık Erişim2011Mild conditions for oxidation/epoxidation of styrene
Kazanci, A.; Saribiyik, O.Y.; Serin, S.
In this study, in order to obtain novel support materials for immobilization of transition metals, polymeric Schiff bases were synthesized using a poly-condensation reaction between ortho(o-)phthalaldehyde tere(t-)phthalaldehyde, oxaldehyde and diamines like, e.g., ethylene-p- phenylene- and o-phenylenediamine. Additionally, catalytic activity of polymeric Schiff base metal on oxidation/epoxidation of styrene complexes were investigated. The products have been characterized on the basis of analytical and spectral method, Fourier transform infrared spectroscopy, 1H- and 13C-nuclear magnetic resonance, gel-permeation chromatography, elemental analysis, thermogravimetric analysis, atomic adsorbtion spectrometry, gas chromatography and gas chromatography mass spectrometry.