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Najafi R.,Islamic Azad University | Kucuk G.D.,Igdr University | Celik E.,Atatürk University
Mathematical Methods in the Applied Sciences | Year: 2017

This paper is devoted to the time-fractional gas dynamics equation with Caputo derivative. Fractional operators are very natural tools to model memory-dependent phenomena. Modified iteration method is proposed to obtain the approximate and analytical solution of the fractional gas dynamics equation. This method is a combined form of the new iteration method and Laplace transform. Modified iteration method really is powerful and simple method compared with other methods. Existence and uniqueness of solution are proven. Numerical results for different cases of the equation are obtained. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Palabiyik I.,Namik Kemal University | Toker O.S.,Yildiz Technical University | Karaman S.,Erciyes University | Yildiz O.,Igdr University
Journal of Cereal Science | Year: 2017

In this work, starch pasting curves were reinterpreted with suitable models to show deficiency of widely used starch pasting parameters in the literature. The aim was to attract scientific attentions to the behavior and dynamics of the curve with respect to process parameters instead of values on the curve. Mainly, pasting curve was separated into four parts combining sigmoidal gelatinization model, exponential thinning model and Arrhenius temperature model. For the gelatinization part, starch swelling rate, water binding capacity and starch resistivities to heat and shear might be compared by the proposed model parameters. Amylose and damaged starch contents of starches had a good relation with Arrhenius and exponential model parameters. Activation energy values gave clues about retrogradation rate of starches and changed between 7142 and 17,327 kJ/mol. © 2017 Elsevier Ltd

PubMed | Igdr University, Atatürk University, Oregon State University and Igdir University
Type: | Journal: Biological research | Year: 2015

The Eurasian grapevine (Vitis vinifera L.) is the most widely cultivated and economically important horticultural crop in the world. As a one of the origin area, Anatolia played an important role in the diversification and spread of the cultivated form V. vinifera ssp. vinifera cultivars and also the wild form V. vinifera ssp. sylvestris ecotypes. Although several biodiversity studies have been conducted with local cultivars in different regions of Anatolia, no information has been reported so far on the biochemical (organic acids, sugars, phenolic acids, vitamin C) and antioxidant diversity of local historical table V. vinifera cultivars grown in Igdir province. In this work, we studied these traits in nine local table grape cultivars viz. Beyaz Kismis (synonym name of Sultanina or Thompson seedless), Askeri, El Hakki, Kirmizi Kismis, Inek Emcegi, Hacabas, Kerim Gandi, Yazen Dayi, and Miskali spread in the Igdir province of Eastern part of Turkey.Variability of all studied parameters is strongly influenced by cultivars (P<0.01). Among the cultivars investigated, Miskali showed the highest citric acid content (0.959g/l) while Kirmizi Kismis produced predominant contents in tartaric acid (12.71g/l). The highest glucose (16.47g/100g) and fructose (15.55g/100g) contents were provided with Beyaz Kismis. Kirmizi Kismis cultivar had also the highest quercetin (0.55mg/l), o-coumaric acid (1.90mg/l), and caffeic acid (2.73mg/l) content. The highest ferulic acid (0.94mg/l), and syringic acid (2.00mg/l) contents were observed with Beyaz Kismis cultivar. The highest antioxidant capacity was obtained as 9.09mol TE g(-1) from Inek Emcegi in TEAC (Trolox equivalent Antioxidant Capacity) assay. Hacabas cultivar had the highest vitamin C content of 35.74mg/100g.Present results illustrated that the historical table grape cultivars grown in Igdir province of Eastern part of Turkey contained diverse and valuable sugars, organic acids, phenolic acids, Vitamin C values and demonstrated important antioxidant capacity for human health benefits. Further preservation and use of this gene pool will be helpful to avoid genetic erosion and to promote continued agriculture in the region.

PubMed | Igdr University and Yuzuncu Yil University
Type: Journal Article | Journal: Food science and technology international = Ciencia y tecnologia de los alimentos internacional | Year: 2016

Gluten-free baked products for celiac sufferers are essential for healthy living. Cereals having gluten such as wheat and rye must be removed from the diet for the clinical and histological improvement. The variety of gluten-free foods should be offered for the sufferers. In the study, gluten-free wafer formulas were optimized using corn, rice and buckwheat flours, xanthan and guar gum blend as an alternative product for celiac sufferers. Wafer sheet attributes and textural properties were investigated. Considering all wafer sheet properties in gluten-free formulas, better results were obtained by using 163.5% water, 0.5% guar and 0.1% xanthan in corn formula; 173.3% water, 0.45% guar and 0.15% xanthan gum in rice formula; 176% water, 0.1% guar and 0.5% xanthan gum in buckwheat formula. Average desirability values in gluten-free formulas were between 0.86 and 0.91 indicating they had similar visual and textural profiles to control sheet made with wheat flour.

PubMed | Igdr University and Yuzuncu Yil University
Type: Journal Article | Journal: Journal of food science and technology | Year: 2015

The effects of 400ppm ascorbyl palmitate (AP) on fatty acids composition, tocopherol, peroxide value (PV) and malonaldehyde (MAD) contents of refined cottonseed oil (CO) and virgin olive oil (OO) during chemical interesterification (CI), and storage at 60C for 28days were investigated. CI significantly decreased (p<0.05) the tocopherol contents of CO and OO. PVs and MAD contents of oil samples considerably increased up to 20min of CI, followed by a reduction at 30min. The unsaturated fatty acids/saturated fatty acids (UFA/SFA) ratios of the samples showed slight but significant (p<0.05) reduction during accelerated oxidation process. Oils with added 400ppm AP had higher tocopherol, and lower PVs and MAD contents than their counterparts without AP during CI, and storage at 60C. AP increased the oxidative stability of interesterified and non-interesterified CO and OO.

PubMed | Igdr University, University of Florence, Yuzuncu Yil University, Atatürk University and King Saud University
Type: Journal Article | Journal: Journal of enzyme inhibition and medicinal chemistry | Year: 2016

Rosmarinic acid (RA) is a natural polyphenol contained in many aromatic plants with promising biological activities. Carbonic anhydrases (CAs, EC are widespread and intensively studied metalloenzymes present in higher vertebrates. Acetylcholinesterase (AChE, E.C. is intimately associated with the normal neurotransmission by catalysing the hydrolysis of acetylcholine to acetate and choline and acts in combination with butyrylcholinesterase (BChE) to remove acetylcholine from the synaptic cleft. Lactoperoxidase (LPO) is an enzyme involved in fighting pathogenic microorganisms, whereas glutathione S-transferases (GSTs) are dimeric proteins present both in prokaryotic and in eukaryotic organisms and involved in cellular detoxification mechanisms. In the present study, the inhibition effects of rosmarinic acid on tumour-associated carbonic anhydrase IX and XII isoenzymes, AChE, BChE, LPO and GST enzymes were evaluated. Rosmarinic acid inhibited these enzymes with Kis in the range between micromolar to picomolar. The best inhibitory effect of rosmarinic acid was observed against both AChE and BChE.

PubMed | Igdr University, University of Florence, King Saud University, Atatürk University and Agri Ibrahim Cecen University
Type: Journal Article | Journal: Journal of enzyme inhibition and medicinal chemistry | Year: 2016

Caffeic acid phenethyl ester (CAPE) is an active component of honeybee propolis extracts. Carbonic anhydrases (CAs, EC are widespread and intensively studied metalloenzymes present in higher vertebrates including humans as many diverse isoforms. Acetylcholinesterase (AChE) is responsible for acetyl choline (ACh) hydrolysis and plays a fundamental role in nerve impulse transmission by terminating the action of the ACh neurotransmitter at cholinergic synapses and neuromuscular junctions. Butyrylcholinesterase (BChE) is another enzyme abundantly present in the liver and released into blood in a soluble form. Lactoperoxidase (LPO) is an enzyme involved in fighting pathogenic microorganisms whereas glutathione S-transferases (GSTs) are dimeric proteins present both in prokaryotic and eukaryotic organisms and involved in cellular detoxification mechanisms. In the present study, the inhibition effect of CAPE on human carbonic anhydrase (hCA) isoforms I, II, IX, and XII, AChE, BChE, LPO, and GST was evaluated. CAPE inhibited these enzymes with Kis in the range between micromolar to picomolar. The best inhibitory effect was observed against AChE and BChE.

Gozuacik C.,Igdr University | Yigit A.,Mustafa Kemal University | Simsek Z.,Cankr Karatekin University
Turkish Journal of Agriculture and Forestry | Year: 2016

This investigation was carried out for possible use of sum of degree-days (total effective temperatures) in order to predict the critical biological stages in chemical control of Sunn pest, Eurygaster integriceps Put. (Hemiptera: Scutelleridae), in 28 wheat fields of Adıyaman, Diyarbakır, and Şanlıurfa provinces from 2007 to 2010, and in climate chamber conditions. Development threshold temperature (°C) of Sunn pest in terms of the life span, starting from egg to new generation of adults, was found as 13.30 °C. Sums of degree-days starting from 1 January to appearance of the eggs, first-stage nymphs (n1), second-stage nymphs (n2), and fourth-stage nymphs (n4) were found with the averages of 44.6, 84.4, 123.3, and 223.1 degree-days, respectively. The results from the field studies reflected that developmental biological data on sum of degree-days as a predictive tool could be useful in better decision making to start chemical applications as soon as the appearance of n1 until n4 for Sunn pest control. © TÜBİTAK.

Altikat S.,Igdr University | Gulbe A.,Igdr University | Celik A.,Atatürk University
Tarim Bilimleri Dergisi | Year: 2015

The objective of this study was to develop a new method to evaluate the seed distribution area in vertical plane and compare it with the other methods. For this purpose, the different calculation methods of seed distribution area namely, standard deviational ellipse, voronoi polygons with delaunay triangulation, integral method, and developed one, the concave hull algorithm was considered and compared in this study. Three different types of no-till seeders equipped with hoe (NS1), single disc (NS2) and winged hoe (NS3) type openers were used and operated at three different tractor forward speeds (0.75 m s−1, 1.25 m s−1 and 2.25 m s−1). According to the results obtained from the study, it was found that the newly developed seed distribution evaluation procedure, concave hull, provided the smaller area values of the distributed seeds as compared to others. The influences of seeders were tested and it was found that the no-till seeder which has disc type furrow opener spread the seeds into larger areas. However, maximum variations of sowing depth values were observed at the no-till seeder with single disc furrow opener. Increasing tractor forward speeds resulted in an increased variation of sowing depth. © 2014, Ankara University. All rights reserved.

PubMed | Igdr University, Bayburt University and Atatürk University
Type: Journal Article | Journal: Environmental toxicology and pharmacology | Year: 2015

It is known that heavy metals have toxic effects on fish. Insufficient measures are a serious problem in our country and around the world. This problem can threaten human health in areas where it is common for people to obtain nutrition from local bodies of water. In this study, the toxicological impacts of some heavy metals were investigated on carbonic anhydrase activity in gilthead gills. Carbonic anhydrase (CA) was purified from gilthead sea bream (Sparus aurata) gills with a specific activity of 2872.92 EU mg(-1) and a yield of 32.84% using affinity chromatography. The overall purification was approximately 84-fold. SDS-polyacrylamide gel electrophoresis showed a single band, and the MW was approximately 30.5 kDa (Soyut et al., 2008, 2012; Soyut and Beydemir, 2008, 2012; Kaya et al., 2013). The kinetic and characteristic properties of CA such as the optimum pH, stable pH, optimum temperature, activation energy (Ea), activation enthalpy (H), Q10, Km and Vmax were determined. Cadmium (Cd(2+)), copper (Cu(2+)), nickel (Ni(2+)) and silver (Ag(+)) inhibited CA activity in in vitro conditions. Ki values were calculated for these metals. Ki values were 31.20mM for cadmium (Cd(2+)), 161.96 mM for copper (Cu(2+)), 10.79 mM for nickel (Ni(2+)) and 0.0082 mM for silver (Ag(+)) based on Lineweaver-Burk plots. Except for cadmium, heavy metals had the same inhibition mechanism. Cadmium was competitive, and the others were noncompetitive.

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