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Öğe Comparison off some properties of free and immobilized ?-amylase by Aspergillus sclerotiorum in calcium alginate gel beads(Taylor & Francis Inc, 2008) Yagar, Hulya; Ertan, Figen; Balkan, BilalSome properties of immobilized a-amylase by Aspergillus sclerotiorum within calcium alginate gel beads were investigated and compared with soluble enzyme. Optimum pH and temperature were found to be 5.0 and 40 degrees C, respectively, for both soluble and immobilized enzymes. The immobilized enzyme had a better Km value, but k(cat)/K-m values were the same for both enzymes. Entrapment within calcium alginate gel beads improved, remarkably, the thermal and storage stability of a-amylase. The half life values of immobilized enzyme and soluble enzyme at 60 degrees C were 164.2, and 26.2 min, respectively. The midpoint of thermal inactivation (T-m) shifted from 56 degrees C (for soluble enzyme) to 65.4 degrees C for immobilized enzyme. The percentages of soluble starch hydrolysis for soluble and immobilized alpha-amylase were determined to be 97.5 and 92.2% for 60 min, respectively.Öğe Determination of the effects of initial glucose on the production of ?-amylase from Penicillium sp under solid-state and submerged fermentation(Taylor & Francis Ltd, 2014) Ertan (Inceoglu), Figen; Balkan, Bilal; Yarkin, ZehraThe effects of catabolite repression of initial glucose on the synthesis of alpha-amylase from Penicillium chrysogenum and Penicillium griseofulvum were investigated under solid-state fermentation (SSF) and submerged fermentation (SmF) systems. The results obtained from either fermentation were compared with each other. In the SmF system, initial glucose concentration above 10 mg/mL completely repressed the production of alpha-amylase from P. chrysogenum and P. griseofulvum. However, the repression in the SSF system was not complete, even when the glucose level was raised to 160 mg/g.Öğe Evaluation of Antioxidant Activities and Antifungal Activity of Different Plants Species Against Pink Mold Rot-Causing Trichothecium roseum(Springer Heidelberg, 2017) Balkan, Bilal; Balkan, Seda; Aydogdu, Halide; Guler, Necmettin; Ersoy, Huseyin; Askin, BuketTrichothecium roseum causes the pink mold rot in many fruits and vegetables around the world. Due to this infection, significant losses arise in foods. In order to control this infection, plant extracts offer alternative treatment for fungicides. In this study, 50 plant species were screened for their antifungal effects against T. roseum. Anthemis arvensis, Origanum vulgare, Sambucus ebulus and Thymus longicaulis powders totally inhibited the mycelia growth of T. roseum at 10% (w/v). The powders of Chelidonium majus and Clinopodium vulgare were effective to T. roseum, with a percentage of inhibition of mycelia growth higher than 70%. MIC of A. arvensis aqueous extracts were lower than the other extracts (125 mu g/ml). Also its extracts inhibited the spore germination by 100% at 1000 mu g/ml. The incidence of the pink mold rot on tomatoes which were treated with C. majus aqueous extracts (75, 150 and 300 mg/ml) was lower than the extracts of other plants when compared to control. At concentration of 300 mg/ml, C. majus extracts prevented the disease by 71.42%. By the SEM, it was determined at the 4MIC extracts, cell wall degradation, swelling, flattening, lysis, collapsing and wrinkling on the hyphal structure. The highest total phenolic and flavanol contents were observed in O. vulgare extracts (310.49 mg GA/g) and T. longicaulis (5.24 mg CE/g). The EC50 values of the experimented extracts were lowered than the EC50 value of Gallic acid (1.87 mg/ml). Meanwhile, in all of the extracts there were phenolic compounds, protocatechuic, chlorogenic, caffeic acid and kaempferol as determined with HPLC system. This research demonstrates that C. majus aqueous extracts may possess high potential to control the pink mold rot on tomatoes as new natural antifungal products.Öğe Evaluation of antioxidant and antifungal activities of several plants against agents of postharvest citrus sour rot and green mould rot(Ars Docendi, 2019) Balkan, Bilal; Aydogdu, Halide; Balkan, Seda; Askin, Buket; Ersoy, HuseyinThe antifungal activities of chloroform extracts of 10 plants species belonging to Lamiaceae family, which were collected from Kirklareli (Turkey), against Geotrichum candidum, theagent of postharvest citrus sour rot and Penicillium digitatum, the agent of postharvest citrus green mould rot, were researched. The lowest Minimum Inhibitory Concentration (MIC) values against G. candidum and P. digitatum were obtained in the extract of Marrubiumperegrinum L. (250 and 125 mu g/ml). In 1000 mu g/ml, the extracts of Melissa officinalis showed 100% inhibition on the spore germination of G. candidum and P. digitatum. In the Scanning Electron Microscope (SEM) observations of G. candidum and P. digitatum that was subjected to M peregrinum extract (4MIC) degenerative changes in the hyphal morphology were seen in the form of cell wall degradation, lysis and collapsing. The highest values of total phenolics were obtained from Mentha pulegium extracts (739.57 mg GAE/g). The lowest EC50 values (0.08 mg/ml) were found in the extracts of M peregrinum and Sideritis montana. The highest flavanol content was determined from M. officialis exctracts (12.71 mg CE/mg). This study demonstrates M. peregrinum extracts may possess high antifungal activity against G. candidum and P. digitatum.Öğe Farklı Ham Nişasta İçeren Tarama Besiyerlerinde Farklı Fungus Türlerinin Amilolitik Aktiviteleri(Trakya Üniversitesi, 2010) Balkan, Bilal; Aydoğdu, Halide; Balkan, Seda; Ertan, FigenThirty-nine fungal species were screened for the production of extracellular amylase hydrolyzing raw starch using a plate culture method. Czapek-Dox Agar containing different raw starch (corn, wheat, potato and rice) was used as culture medium for screening. Among these, thirteen, twelve, seven and five fungi showed higher amylolytic activity on solid medium containing raw wheat starch, raw rice starch, raw potato starch and raw corn starch, respectively. Two fungi did not show any amylolytic activityÖğe Katı substrat fermentasyonu ile ham nişastayı parçalayan yeni bir fungal amilaz üretimi saflaştırılması ve biyokimyasal özelliklerinin belirlenmesi(Trakya Üniversitesi Fen Bilimleri Enstitüsü, 2008) Balkan, Bilal; Ertan, FigenBu çalışmada, yeni bir ham nişasta hidrolizleyen fungal amilazın SSF yöntemi ile üretilmesi, saflaştırılması ve bazı biyokimyasal özelliklerinin belirlenmesi amaçlanmıştır. Ham nişastayı hidrolizleyen amilaz taraması sonucunda en iyi aktiviteye Penicillium brevicompactum' un sahip olduğu bulundu ve amilaz kaynağı olarak kullanıldı. Buğday kepeği, pirinç kabuğu ve ayçiçeği küspesi en iyi substratı belirlemek için test edildi. En iyi katı substratın buğday kepeği olduğu belirlendi. Amilaz üretimi için katı substrat fermentasyon şartları optimize edildi. Optimum fermentasyon şartları, başlangıç nem içeriği % 55, nemlendirici ajan 0.1 M sodyum fosfat tamponu (pH 5.0), üretim süresi 7 gün, aşı miktarı 2.5 mL ve üretim sıcaklığı 30 oC olarak saptandı. Penicillium brevicompactum amilazı nişasta afinite metodu kullanılarak 45.98 kez saflaştırıldı. Saflaştırılan enzimin çözünür nişasta için Km değeri 5.71 mg/ml, Vmax değeri ise 666.6 U/ml olarak hesaplandı. Enzim 30-50 oC arasında ve pH 5.0 de maksimum aktivite gösterdi. 30 oC' de 45 dk. inkübasyondan sonra başlangıç aktivitesini %100 korudu. pH 4.0-5.0 arasında kararlı idi. Mn+2, Cu+2 and Na+ iyonları enzim aktivitesini arttırırken Mg+2, K+, Fe+3 ve EDTA enzim aktivitesini inhibe etti. P. brevicompactum ?-amilazının molekül ağırlığı SDS-PAGE ile 32.5 kDa olarak tespit edildi. Anahtar Kelimeler: ?-amilaz, katı substrat fermentasyon, ham nişasta sindirimi, saflaştırma, Penicillium brevicompactum.Öğe Optimization of ?-amylase immobilization in calcium alginate beads(Taylor & Francis Inc, 2007) Ertan, Figen; Yagar, Hulya; Balkan, Bilalalpha-Amylase enzyme was produced by Aspergillus sclerotiorum under SSF conditions, and immobilized in calcium alginate beads. Effects of immobilization conditions, such as alginate concentration, CaCl2 concentration, amount of loading enzyme, bead size, and amount of beads, on enzymatic activity were investigated. Optimum alginate and CaCl2 concentration were found to be 3% (w/v). Using a loading enzyme concentration of 140 U mL(-1), and bead (diameter 3 mm) amount of 0.5 g, maximum enzyme activity was observed. Beads prepared at optimum immobilization conditions were suitable for up to 7 repeated uses, losing only 35% of their initial activity. Among the various starches tested, the highest enzyme activity (96.2%) was determined in soluble potato starch hydrolysis for 120 min at 40 degrees C.Öğe Penicillium chrysogenum'dan alfa-amilaz üretimi(Trakya Üniversitesi, 2003) Balkan, Bilal; Ertan, FigenÖZET Bu çalışmada bazı fungus türlerinin a-amilaz enzimi açısından taranması ve Penicillium chrysogenum a-amilazının bazı biyokimyasal özelliklerinin belirlenmesi amaçlanmıştır. Penicillium chrysogenum a-amilazı için optimum üretim şartları araştırıldığında, üretim süresi 7. ve 8. gün, üretim sıcaklığı 30°C, başlangıç pH sı 4.0 olarak bulundu. Üretim ortamına eklenen karbon kaynaklarının a-amilaz sentezine etkisi araştırıldığında, en yüksek aktivite %2.0 maltoz içeren ortamda saptandı. Enzimin optimum çalışma koşulları incelendiğinde, inkübasyon pH'sı 5.0, inkübasyon sıcaklığı 30°C olarak bulundu. Penicillium chrysogenum a-amilazının pH ve termal kararlılığı araştırıldığında, enzimin pH 4.0-7.0 aralığında kararlı olduğu ve aktivitesini 30°C'de 20 dk. koruduğu gözlendi. Penicillium chrysogenum a-amilazının hidroliz ürünleri maltoz, belirlenemeyen oligosakkaritler ve az miktar da glukoz olduğu saptandı. Anahtar Kelimeler; a-amilaz, Penicillium chrysogenum, üretim.Öğe Production of ?-amylase from Penicillium chrysogenum under solid-state fermentation by using some agricultural by-products(Faculty Food Technology Biotechnology, 2007) Balkan, Bilal; Ertan, FigenSolid-state fermentation (SSF) was carried out using corncob leaf (CL), rye straw (RS), wheat straw (WS) and wheat bran (WB) as substrates for a-amylase production by a fungal culture of Penicillium chrysogenum. The effects of moisture level, particle size and inoculum concentration on enzyme synthesis from R chrysogenum were investigated. Optimal moisture levels of substrates were 75, 65, 65 and 55% for CL, WS, WB and RS substrates, respectively. Optimal particle size and inoculum concentration for the production of alpha-amylase were: >1 mm, 20%; >1 mm, 20%; 1 mm, 20% and >1 mm, 30% for CL, WS, WB and RS, respectively WB showed the highest enzyme production with 160 U/mL under optimum conditions. The other enzyme activities were 28, 49 and 45 U/mL using CL, RS and WS, respectively.Öğe THE PRODUCTION OF A NEW FUNGAL -AMYLASE DEGRADED THE RAW STARCH BY MEANS OF SOLID-STATE FERMENTATION(Taylor & Francis Inc, 2010) Balkan, Bilal; Ertan, FigenIn this study, it was intended to produce a new fungal amylase by solid-state fermentation and purification and also to determine some of its biochemical properties. It was found that Penicillium brevicompactum had the best enzyme activity according to screening methods with amylase degrading raw starch, and P. brevicompactum was selected as the amylase source. Wheat bran, rice husks, and sunflower oil meal were tested to determine the best solid substrate. Wheat bran was determined as the best of these. The fermentation conditions were optimized for the production of amylase. The optimum fermentation conditions were found to be an initial moisture level for the solid substrate of 55%, moistening agent of 0.1M sodium phosphate buffer (pH 5.0), incubation period of 7d, inoculum concentration of 2.5mL, and incubation temperature at 30 degrees C. Penicillium brevicompactum -amylase was purified 45.98 times by the starch affinity method. The Km and Vmax values of -amylase for soluble starch were 5.71mg/mL and 666.6U/mL, respectively. This amylase showed maximum activity at between 30 and 50 degrees C and at pH 5.0. Initial enzyme activity was kept at 100% after incubation at 30 degrees C for 45min. Enzyme was stable in the pH range of 4.0-5.0. This enzyme was activated by Mn2+, Cu2+, and Na+ ions, and was inhibited by Mg2+, K+, Fe3+, and ethylenediamine tetraacetic acid (EDTA). The molecular mass of P. brevicompactum -amylase was found to be 32.5kD by sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis.Öğe Solid state fermentation for the production of ?-amylase from Penicillium chrysogenum using mixed agricultural by-products as substrate(Springer, 2006) Ertan, Figen; Balkan, Bilal; Balkan, Seda; Aktac, TulinProduction of a-amylase from local isolate, Penicillium chrysogenum, under solid-state fermentation (SSF) was carried out in this study. Different agricultural by-products, such as wheat bran (WB), sunflower oil meal (SOM), and sugar beet oil cake (SBOC), were used as individual substrate for the enzyme production. WB showed the highest enzyme activity (750 U/gds). Combination of WB, SOM, and SBOC (1:3:1 w/w/w) resulted in a higher enzyme yield (845 U/gds) in comparison with the use of the individual substrate. This combination was used as mixed solid substrate for the production of a-amylase from P. chrysogenum by SSF. Fermentation conditions were optimized. Maximum enzyme yield (891 U/gds) was obtained when SSF was carried out using WB + SOM + SBOC (1:3:1 w/w/w), having initial moisture of 75 %, inoculum level of 20 %, incubation period of 7 days at 30 degrees C. Galactose (1 % w/w), urea and peptone (1 % w/w), as additives, caused increase in the enzyme activity.
