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81.
In this study, the antioxidant and antiradical properties of some phyto lignans (nordihydroguaiaretic acid, secoisolariciresinol, secoisolariciresinol diglycoside, and α-(-)-conidendrin) and mammalian lignans (enterodiol and enterolactone) were examined by different antioxidant assays. For this purpose, radical scavenging activities of phyto and mammalian lignans were realized by 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) radical (ABTS•+) scavenging assay and 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) scavenging assay. Additionally, the reducing ability of phyto and mammalian lignans were evaluated by cupric ions (Cu2+) reducing (CUPRAC) ability, and ferric ions (Fe3+) and [Fe3+-(TPTZ)2]3+ complex reducing (FRAP) abilities. Also, half maximal inhibitory concentration (IC50) values were determined and reported for DPPH• and ABTS•+ scavenging influences of all of the lignan molecules. The absorbances of the lignans were found in the range of 0.150–2.320 for Fe3+ reducing, in the range of 0.040–2.090 for Cu2+ reducing, and in the range of 0.360–1.810 for the FRAP assay. On the other hand, the IC50 values of phyto and mammalian lignans were determined in the ranges of 6.601–932.167 µg/mL for DPPH• scavenging and 13.007–27.829 µg/mL for ABTS•+ scavenging. In all of the used bioanalytical methods, phyto lignans, as secondary metabolites in plants, demonstrated considerably higher antioxidant activity compared to that of mammalian lignans. In addition, it was observed that enterodiol and enterolactone exhibited relatively weaker antioxidant activities when compared to phyto lignans or standard antioxidants, including butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), Trolox, and α-tocopherol. 相似文献
82.
Lokman Durmaz Adem Erturk Mehmet Akyüz Leyla Polat Kose Eda Mehtap Uc Zeynebe Bingol Ruya Saglamtas Saleh Alwasel lhami Gulcin 《Molecules (Basel, Switzerland)》2022,27(10)
Coumestrol (3,9-dihydroxy-6-benzofuran [3,2-c] chromenone) as a phytoestrogen and polyphenolic compound is a member of the Coumestans family and is quite common in plants. In this study, antiglaucoma, antidiabetic, anticholinergic, and antioxidant effects of Coumestrol were evaluated and compared with standards. To determine the antioxidant activity of coumestrol, several methods—namely N,N-dimethyl-p-phenylenediamine dihydrochloride radical (DMPD•+)-scavenging activity, 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulphonate) radical (ABTS•+)-scavenging activity, 1,1-diphenyl-2-picrylhydrazyl radical (DPPH•)-scavenging activity, potassium ferric cyanide reduction ability, and cupric ion (Cu2+)-reducing activity—were performed. Butylated hydroxyanisole (BHA), Trolox, α-Tocopherol, and butylated hydroxytoluene (BHT) were used as the reference antioxidants for comparison. Coumestrol scavenged the DPPH radical with an IC50 value of 25.95 μg/mL (r2: 0.9005) while BHA, BHT, Trolox, and α-Tocopherol demonstrated IC50 values of 10.10, 25.95, 7.059, and 11.31 μg/mL, respectively. When these results evaluated, Coumestrol had similar DPPH•-scavenging effect to BHT and lower better than Trolox, BHA and α-tocopherol. In addition, the inhibition effects of Coumestrol were tested against the metabolic enzymes acetylcholinesterase (AChE), butyrylcholinesterase (BChE), carbonic anhydrase II (CA II), and α-glycosidase, which are associated with some global diseases such as Alzheimer’s disease (AD), glaucoma, and diabetes. Coumestrol exhibited Ki values of 10.25 ± 1.94, 5.99 ± 1.79, 25.41 ± 1.10, and 30.56 ± 3.36 nM towards these enzymes, respectively. 相似文献
83.
Kurei Tatsuki Hioki Yuto Kose Ryota Nakaba Satoshi Funada Ryo Horikawa Yoshiki 《Cellulose (London, England)》2022,29(5):2885-2898
Cellulose - Structural control is essential for further development of cellulosic materials. Here, we demonstrated the significance of the orientation and degree of polymerization in the integrated... 相似文献
84.
85.
Özlem Gündoğdu Pınar Turhan Aytekin Köse Ramazan Altundaş Yunus Kara 《Tetrahedron: Asymmetry》2017,28(9):1163-1168
The ring-opening reaction of homoserine lactone with phenylmagnesium bromides was systematically examined. A reliable method to achieve β-amino acid precursors was developed by tuning the reaction conditions to favor mono-addition to the carbonyl moiety of the lactone. 相似文献
86.
87.
Satoshi Moriwaki Yasuhiko Terada Katsumi Kose Tomoyuki Haishi Yoshihiko Sekozawa 《Applied magnetic resonance》2014,45(6):517-525
Three-dimensional magnetic resonance (MR) images of four kinds of fruit (Japanese apricot, peach, Japanese pear, and apple) were acquired throughout their growing periods (from April to August) to visualize and quantify their vascular structures. The vascular structures were emphasized using T 1-weighted spin-echo or gradient-echo pulse sequences, visualized using a maximum-intensity projection technique, and quantified using an image-segmentation program. As a result, we demonstrated that the vascular volume changed almost in proportion to the whole volume and that larger fruits generally had larger proportionality constants. We therefore concluded that MR microimaging is a powerful tool for studies of the vascular structure of fruit. 相似文献
88.
Spatial mapping of velocity power spectra in Taylor-Couette flow using ultrafast NMR imaging 总被引:1,自引:0,他引:1
Kose K 《Physical review letters》1994,72(10):1467-1470
89.
Bayri A. Sl M. Aytekin . 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2006,80(1):S45-S48
In this study, the possible antiferromagnetic interactions in a dinuclear entity have been considered. It has been realized that, if the proposed structure is a real structure, there should be antiferromagnetic interactions between the dinuclear Fe(III) ions. It is also suggested that the predicted theoretical results should be tested with additional experimental measurements 相似文献
90.
AytekinGUile 《应用数学和力学(英文版)》2004,25(7):806-811
The numerical solution for a type of quasilinear wave equation is studied. The three-level difference scheme for quasi-linear waver equation with strong dissipative term is constructed and the convergence is proved. The error of the difference solution is estimated. The theoretical results are controlled on a numerical example. 相似文献