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Öğe Bazı yerlı̇ elma çeşı̇tlerı̇nı̇n fı̇tokı̇myasal analı̇zı̇ ve elma ağacı yapraklarının ksı̇lanaz üretimı̇nde değerlendı̇rı̇lmesı̇(2015) Sutay Kocabaş, Didem; Tur, Eren; Kocabaş, AytaçBu çalışmada, Golden delicious, Red delicious ve Granny smith elma çeşitlerinin sulu özüt bileşimleri gaz kromatografisi-kütle spektroskopisi (GC-MS) tekniğiyle belirlenmiştir. En yüksek antioksidan aktivite Red delicious elma kabuğunda (3.32±0.34 mg/ml EC50 değeri), buna karşılık gelen toplam fenolik içeriği (754.4±43.3 mg GAE/100 g kuru ağırlık) ile belirlenmiştir. En yüksek protein içeriği (%2.09±0.07) ise Granny smith elma kabuğunda tespit edilmiştir. Granny smith elmaların bir diğer üstün özelliği de, Gram pozitif ve Gram negatif bakterilere karşı gösterdiği antimikrobiyel aktivitedir. Genel olarak, kabuklardaki protein konsantrasyonu etli kısımlara göre %36 daha yüksek bulunmuştur. Ayrıca, elma ağacı yaprakları kullanılarak katma değerli bir ürün (ksilanaz) üretimi atık değerlendirme yaklaşımıyla incelenmiştir. En yüksek enzim üretimi (64.7±5.3 IU/ml) Red delicious elma ağacı yaprakları kullanılarak elde edilmiştir.Öğe Comparative Analysis Of Phytochemical Constituents, Antioxidant And Antimicrobial Activity, Phenolic And Protein Content Of Karaman-Grown Apples(Yayıncı Yok, 2014-06) Sutay Kocabaş, Didem; Tur, Eren; Kocabaş, AytaçA healthy diet, consisted of fruits and vegetables, has been known to be effective in the prevention of chronic diseases. Apples are a very significant part of the human diet since they are rich in phenolic compounds and antioxidant activity. Currently, Turkey is the fifth country for apple production in the world and Karaman province is the second biggest apple producer of Turkey. The aim of this study was the comparative investigation of phytochemical compositon, antioxidant and antimicrobial activities, total phenolic and protein content of apples. To mimic general public apple consumption, Golden Delicious, Red Delicious (Starking) and Granny Smith apple types, which are produced and consumed at the highest amount, were obtained from local market farmers in Karaman and water extracts of apples were investigated. Peel and fleshy parts of apples were separately peeled, dryed, grinded and extracted. Compositons of the water extracts were determined by gas chromatography-mass spectroscopy (GC-MS) technique and twelve different components were identified in investigated samples. The highest chemical composition ratio was predicted in Golden Delicious type apples. The highest antioxidant activity was determined in peels of the Starking type apples (5.59 mg/ml for 50% DPPH inhibiton) with corresponding total phenolic content (>40 µg/ml). Lowest antioxidant activity (16.53 µg/ml) was detected in peels of Granny Smith type apples. Antimicrobial activity was observed only in the peels of Golden Delicious type apples. Protein analysis revealed that protein concentrations in the peels are averagely 36% higher than the fleshy parts of the tested apple types.Öğe Crystallization of Scytalidium thermophilum Xylanase by Vapor Diffusion(Yayıncı Yok, 2014-05) Sutay Kocabaş, Didem; Tur, ErenThe main heteropolymers of the hemicellulosic fraction of plant biomass are xylan, mannan, galactans and arabinans [1]. Xylan is a complex molecule mainly consisting of a five-carbon sugar D-xylose. Due to the complex structure of xylan, synergistic action of different hemicellulase enzymes is required for complete hydrolysis. Endoxylanases are one of the most important enzymes in this enzyme group. Microbial xylanase producers are mainly bacteria and fungi [2]. Filamentous fungi produce extracellular xylanase which makes fungal xylanases favorable at industrial scale such as animal feed production, manufacture of bread, food and drinks, pharmaceutical and chemical applications, textiles, pulp and paper. For crystallographic purposes, xylanase from Scytalidium thermophilum was purified to homogeneity by a two-step column chromatography technique including gel filtration and anion exchange, 21.8 fold with 9.6% yield. Xylanase crystallization was screened using ready-to-use screening kits by sitting drop vapor diffusion technique in 96-well plates. After dye test of observed crystals, xylanase-crystal forming conditions were optimized in 24-well plates by hanging drop vapor diffusion technique. So far, best crystals, having potential for X-ray structure studies, were obtained using ammonium citrate dibasic and sodium acetate trihydrate at 18°C at 3 mg/ml protein concentration as shown in Figure 1.Öğe Endüstriyel uygulamar için scytalidium thermophilum ksilanazının tarımsal atıklar kullanılarak üretimi, saflaştırılması, karakterizasyonu ve X-ışını yapı analizi amacıyla kristalizasyonu(2014) Kocabaş, Didem Sutay; Özben, Neslihan; Güder, Sevgi; Tur, ErenBu çalışmada, termofilik bir küf olan Scytalidium thermophilum’dan ksilanaz üretim koşulları, Box-Behnken deney tasarım yöntemi kullanılarak tepki yüzey metodolojisi ile istatistiksel olarak optimize edilmiştir. Çalışılan aralıkta en uygun fermantasyon koşulu 1 ml aşı oranı, 50°C sıcaklık, 7,0 pH, 20 g/l mısır koçanı ve 5 g/l maya özütü olarak belirlenmiştir. Optimum koşullarda gerçekleştirilen fermantasyon sonucunda 134,09 IU/ml ksilanaz aktivitesi tespit edilmiştir. Bu sonucun, geliştirilen model eşitliğinden hesaplanan 133,91 IU/ml değeriyle uyumlu olduğu belirlenmiştir. Optimizasyon çalışmaları sonucunda enzim üretimi, başlangıç seviyesinin yaklaşık 2 katına çıkarılmıştır. Ksilanazın kısmi saflaştırılması amonyum sülfatla çöktürme, sulu iki faz ayrıştırma ve ultrafiltrasyon yöntemleri ile gerçekleştirilmiştir. Amonyum sülfatla çöktürme sonucunda %52 verimle 2,5 kat saflaştırma elde edilirken, sulu iki faz ayrıştırma tekniğinde %79 verim ve 2,7 kat, ultrafiltrasyon tekniğinde ise %25 verimle 4,3 kat saflaştırma elde edilmiştir. Ksilanazın tam saflaştırılması için jel filtrasyon ve anyon değişim kolon kromatografi teknikleri kullanılmış, enzim %9,6 verimle 21,8 kat saflaştırılmıştır. Ksilanazın molekül ağırlığı ve izoelektrik noktası sırasıyla 21 kDa ve pH 8,6 olarak bulunmuştur. Ham ksilanaz için optimum sıcaklık ve pH değerleri sırasıyla 70°C ve pH 7,0 olarak tespit edilmiştir. Saf ksilanaz için ise bu değerler sırasıyla 65°C ve pH 6,5 olarak bulunmuştur. Hem ham hem de saf enzim alkali pH koşullarında daha yüksek aktivite göstermiş ve her iki enzim formu da 60ºC’de 1 saatlik inkübasyon sonunda aktivitesinin yaklaşık %50’sini korumuştur. Saf enzimin Km ve Vmax değerleri sırasıyla 2,2±0,06 mg ksilan/ml ve 168,2±4,2 olarak tespit edilmiştir. Substrat seçiciliği incelemesi sonucunda ksilanazın, denenen lignoselülozik substratlar içinde en yüksek afiniteyi buğday kepeğine karşı gösterdiği belirlenmiştir. Ksilanazın biyokütle hidroliz potansiyeli mısır koçanı üzerinde araştırılmış ve enzimatik hidroliz sonucunda mısır koçanının morfolojisinde ortaya çıkan belirgin değişimler SEM analizi ile gözlemlenmiştir. Projenin son basamağı ise saf ksilanazın X-ışını analizi amacıyla kristalizasyonunu içermektedir. Optimize edilen kristalizasyon koşullarında S. thermophilum ksilanazı hem boyutsal hem de yapısal açıdan X-ışını analizine uygun bir kristal olarak elde edilebilmiştirÖğe Plasma modified membrane for daily recovery of oil from repeated frying operation with frequent oil replenishment(Springer, 2013) Onal Ulusoy, Baran; Tur, Eren; Mutlu, MehmetSunflower oil was used for deep frying of potatoes at 170 +/- A 5 A degrees C and for 8 h per day for 5 days in a fryer with an automatic oil filtration system. Three different frying operations were performed: operation (OP)-1, OP-2 and OP-3; that correspond to the oil unfiltered at the end of each frying day, the oil filtered through the fryer's own filter (passive filtration) and the oil firstly subjected to passive filtration and then filtered through a polyethersulfone membrane modified with hexamethyldisiloxane via radio frequency plasma (75 W-5 min, discharge power-time), respectively. The performance of each operation was investigated in terms of free fatty acids (FFA), conjugated dienoic acids (CD), TOTOX value, total polar content (TPC), Hunter color, viscosity, fatty acid composition, and tocopherol content. The results showed that OP-3 could decrease FFA, CD, TOTOX, TPC, L*a*b* value, viscosity and linoleic acid (18:2)/palmitic acid (16:0) ratio in 29.6, 11.7, 25, 30.8, 6.1*11.3*20.8*, 7.8, 12.2 %, respectively, compared to the unfiltered oil (OP-1). Regenerated oil from OP-3 had a frying life approximately 17 h more than oils from both OP-1 and OP-2.Öğe Plasma polymerization modified polyvinylidene fluoride (pvdf) membrane development and characterization for degumming of soybean oil(Springer, 2014) Önal-Ulusoy, Baran; Tur, Eren; Akdoğan, Ebru; Mutlu, MehmetUnmodified and surface-modified polyvinylidene fluoride (PVDF) membranes were tested for their ability to degum soybean crude oil and crude oil miscellas. The membrane was modified with 1,1,1,3,3,3-hexafluoro-2-propanol or hexamethyldisiloxane (HMDSO) by radio-frequency plasma polymerization at 10-100 W glow discharge power and 1-30 min contact time. The membranes were characterized by contact angle measurements, attenuated total reflectance Fourier transform infrared spectroscopy, atomic force microscopy, and scanning electron microscopy. Modification of the PVDF membrane with HMDSO at 60 W power for 5 min increased the interfacial free energy between water and solid surface from 30 +/- A 2 to 64 +/- A 2 mJ/m(2). This membrane was tested for permeate flux and phospholipid rejection with crude oil and different concentrations of miscella. Although formation of the polymer film on the membrane tended to decrease membrane pore size, the modified membrane had an oil flux as good as the unmodified membrane did. In addition, the modified-membrane improved the phospholipid rejection and removed 76 % of the phospholipids from the crude oil and 81-90 % of the phospholipids from crude oil miscellas.Öğe Purification strategies of Scytalidium thermophilum xylanase(Yayıncı Yok, 2014-06) Sutay Kocabaş, Didem; Güder, Sevgi; Özben, Neslihan; Tur, ErenXylanase (E.C.3.2.1.8) is an enzyme which hydrolyses b-1,4 bonds in xylan backbone which consists of D-xylose molecules. Based on its function, xylanase is used in many industries. For animal feed, paper production and textile industry partially purified xylanase can be acceptable, but for bakery and beverage industry, chemical or pharmaceutical applications, high purity is generally required. In this study, xylanase was produced from a thermophilic fungus, Scytalidium thermophilum and purification strategies were developed for industrial and analytical purposes. In addition, within the cost reduction approach, corn cobs are used as carbon source in the culture medium which are produced millions of tons as agricultural waste each year and have very low economical value. Partial purification of xylanase was studied with ammonium sulphate precipitation (ASP), aqueous two phase system (ATPS) and ultrafiltration (UF). Precipitation with the usage of 50% (v/v) ammonium sulphate concentration gave the best results as 2.5 fold purification and 52% yield. TX-114 was employed at a concentration of 7% (v/v) for ATPS and 2.7 fold purification with 79% yield was obtained. Three-step UF technique was practiced using membranes with different MWCO values; which were 100, 30 and 10 kDa, sequentially. As the result of this technique, 4.3 fold purification with 25% yield was attained. With these results, partially purified xylanase can be presented as an ingredient for industrial applications. For analytical purification of enzymeÖğe Purification, Characterization and Crystallization of Scytalidium thermophilum Xylanase(Yayıncı Yok, 2014) Sutay Kocabaş, Didem; Tur, Eren; Güder, SevgiXylanases are hydrolytic enzymes responsible for xylan depolymerization. Xylan is the complex polysaccharide of the plant cell wall mainly consisting of D-xylose as the monomeric unit and it is the most abundant non-cellulosic renewable polysaccharide on the earth (Beg et al. 2001, Dhiman et al. 2008). Fungal xylanases are favorable at industrial scale such as animal feed production, manufacture of bread, food and drinks, pharmaceutical and chemical applications, textiles, pulp and paper production (Polizeli et al. 2005). Microbial xylanases are preferred biocatalysts in industry due to their high substrate specificity, mild reaction conditions, conservation of substrate and insignificant side product formation (Kulkarni et al 1999).
