Browsing by Author "Ozturk, Mehmet"

Now showing 1 - 5 of 5

Antioxidant and Anticholinesterase Constituents of Salvia Poculata
(Tubitak Scientific & Technological Research Council Turkey, 2009) Kolak, Ufuk; Hacibekiroglu, Isil; Ozturk, Mehmet; Ozgokce, Fevzi; Topcu, Guelacti; Ulubelen, Ayhan
Two triterpenoids, namely 2 alpha,3 alpha-dihydroxy-24-nor-4(23), 12-oleanadien-28-oic acid (1) and ursolic acid (2); 4. avonoids, namely 5-hydroxy-7,4'-dimethoxyflavone (3), cirsimaritin (4), eupatilin (5), and salvigenin (6); a diterpenoid, namely sclareol (7); and a steroid, namely beta-sitosterol (8), were isolated from the aerial parts of Salvia poculata Nab., a Turkish endemic Salvia species. Total phenolic and flavonoid contents of the crude extract were determined as pyrocatechol and quercetin equivalents, respectively. The antioxidant activity of the crude extract and the isolated compounds (2-8) was established using beta-carotene bleaching, superoxide anion radical, and ABTS cation radical scavenging activity. In addition, the anticholinesterase activity of the crude extract and the isolated compounds (2-8) against the enzymes acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) was determined. The phytochemistry and antioxidant and anticholinesterase activities of S. poculata were investigated for the first time in this study. The crude extract of S. poculata exhibited a significant antioxidant effect as well as butyrylcholinesterase inhibitory activity. Ursolic acid (2) and cirsimaritin (4) possessed high butyrylcholinesterase inhibitory activity.
Determination and Comparison of Metal Contents in Simulated Body Fluid Medium Conditions of the Plant Species by Flame Atomic Absorption Spectrometry (Faas)
(Marmara Univ, 2022) Umaz, Adil; Aydin, Firat; Tokul Olmez, Ozge; Firat, Mehmet; Ozturk, Mehmet; Ertas, Abdulselam; Aydin, Isil
The importance of plants in folk medicine and scientific studies is increasing day by day. In this context, the plants pose a danger to human health when they are eaten by the public, consumed as herbal tea or used as medicinal plants especially the toxic metals in their composition. For this reason, determining the macro, micro and toxic element content in the plants is important for health. In this study; the metal contents of root and aerial parts of nine different Salvia species were determined and the chemometric evaluation of the obtained results was made. In the principal component analysis (PCA) made with 20 elements of Salvia species, it was determined that the first two principal components explained 62.60% of the variance and the first six principal components explained 92.70%. When PCA and hierarchical cluster analysis (HCA) results are evaluated; the parts of Salvia species root and aerial parts were determined that were not clearly separated and there was no regional grouping. In addition, Salvia species prepared as herbal tea was left to different simulated body fluid medium conditions, and the changes in metal contents were examined. It was determined that were taken up Cr, Cd, Pb, Cu, Zn metals in the simulated saliva fluid (SSF), Ni, Mn metals in the simulated gastric fluid (SGF), and Na, K metals in the simulated intestinal fluid (SIF). It was determined that Fe metal in almost all Salvia species was not taken from three simulated body fluid mediums. Thus, elements determined which were taken up in body fluid mediums.
Essential Oil, Aroma, and Fatty Acid Profiles of Five Endemic Salvia Taxa From Turkey With Chemometric Analysis
(Wiley-v C H verlag Gmbh, 2022) Ertas, Abdulselam; Akdeniz, Mehmet; Yener, Ismail; Ozturk, Mehmet; Olmez, Ozge Tokul; Firat, Mehmet; Kolak, Ufuk
The essential oil, aroma, and fatty acid compositions of Salvia cerino-pruinosa var. cerino-pruinosa, S. cerino-pruinosa var. elazigensis, S. pseudeuphratica, S. rosifolia, and S. kurdica collected in 2015, 2016, and 2017 were analysed by GC-FID, GC/MS/Head Space and GC/MS. The results were evaluated chemometrically for principal component analyses and hierarchical clustering analyses using Minitab program. The main components of their essential oils have been determined as germacrene-D (41.79 % highest for these species), camphor (55.80 %), linalool (33.38 %), caryophyllene oxide (32.99 %), 1,8-cineole (26.30 %) and geraniol acetate (31.63 %), while for aroma 1,8-cineole (45.95 % highest for these species), camphor (58.54 %), D-limonene (40.83 %), linalool (27.67 %) and cis-linalool oxide (25.87 %). Oleic (72.65 % highest for these species), erucic (44.61 %), 2-palmitoleic (42.17 %) and nervonic (32.61 %) acids were determined as major components of their fatty acids. According to the PCA and HCA, the essential oil components of these Salvia taxa unaffected by the years, and accordingly, the Salvia taxa grouped among themselves.
Norditerpene Alkaloids From Delphinium Linearilobum and Antioxidant Activity
(Pergamon-elsevier Science Ltd, 2006) Kolak, Ufuk; Ozturk, Mehmet; Ozgokce, Fevzi; Ulubelen, Ayhan
From the roots of Delphinium linearilobum (Trautv.) N. Busch two new norditerpene alkaloids linearilobin and linearilin, and the known alkaloids lycoctonine, 14-acetyltalatizamine, browniine, cammaconine, talatizamine, and cochlearenine were isolated. Spectroscopic techniques were used for structure determination. Antioxidant activity was performed by DPPH and metal chelating activity assays. (c) 2006 Elsevier Ltd. All rights reserved.
Synthesis and Characterization of Utsa-76 Metal Organic Framework Containing Lewis Basic Sites for the Liquid-Phase Adsorption of Uvi
(Elsevier, 2021) Ozturk, Mehmet; Zorer, Ozlem Selcuk; Gulcan, Mehmet
UTSA-76 encoded MOF structure containing Lewis basic groups was efficiently synthesized and characterized for the removal of U-VI from the liquid phase by using adsorption technique. H-1, C-13-NMR, FT-IR, P-XRD, TEM, TEMEDX, BET, SEM and SEM-EDX mapping techniques were applied to define this adsorbent material. Adsorption of U-VI on the synthesized UTSA-76 structure was investigated depending on the parameters of pH, temperature, mixing time and solution concentrations. In the kinetic of adsorption process, not only the pseudo-second-order kinetic, but also film diffusion was effective. The adsorption equilibrium of U-VI on UTSA-76 explained better by Langmuir isotherm model and the qmax from Langmuir isotherm was calculated as 91.31 mg/g. The synthesized MOF structure (UTSA-76) demonstrated a removal rate from 12 ppm to 0.25 ppm in 45 min to a very low UO22+ ion concentration of about 98 % using a low adsorbent mass of 5 mg, and UTSA-76 with this adsorption performance will be among the highly preferred effective adsorbents for uranium adsorption.