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Katı substrat fermentasyonu (KSF), doğal substratların kullanıldığı, serbest suyun olmadığı bir işlemdir. Biyoteknolojik süreçlerde alternatif bir metod olan bu fermentasyon işlemi, yüksek aktivite ve daha düşük maliyetli lakkaz üretimi için lignoselülozlu ham maddeleri kullanmaktadır. Organizmalar bu katı substratları hem bağlanma yeri hem de besin olarak kullanmaktadır. Biyolojik süreçlerde lignoselülozlu ham maddelerin kullanımı, çevresel problemlerin çözümüne yardımcı olabilmektedir.Bu çalışmada, yeni izole edilmiş olan Funalia trogii, Ganoderma lucidum ve Trametes versicolor'ın lakkaz üretimi KSF sürecinde araştırıldı. Farklı faktörlerin (katı substrat, sıcaklık, pH, nem içeriği ve indükleyiciler) lakkaz üretimine etkisi test edildi. Test edilen lignoselülozlu katı substratlar arasından buğday kepeği, lakkaz üretimi için en iyi katı substrat olarak belirlendi. Fungusların lakkaz üretimi üzerine soya unu, ağaç yaprakları, maya özütü ve bakırın etkisi de araştırıldı. Yüksek lakkaz aktivitesi için en iyi ortam, bakır ilave edilmiş buğday kepeği+soya unu ortamıdır. Optimum KSF koşulları, %75 nem içeriği, 30°C ve pH 5-6 dır.KSF cam tava tipi fermentör kullanılarak da yürütüldü ve en yüksek lakkaz aktiviteleri F.trogii, G.lucidum ve T.versicolor için sırasıyla 22469±2622, 2008±826 ve 2649±810 U/L olarak elde edildi.Ayrıca, bakır ilave edilmiş olan buğday kepeği+soya unu ortamlarında üretilen F.trogii, G.lucidum ve T.versicolor'dan elde edilen ham lakkazın aktivite ve kararlılığı üzerine pH ve sıcaklığın etkisi test edildi. Bu ham lakkazlar, özellikle pH 2.5-3.5 da yüksek aktivite gösterdi. Yüksek sıcaklıkta da kararlı oldukları gözlendi. G.lucidum ham lakkazının Remazol Brilliant Blue R (RBBR) renk giderimi aktivitesi, optimum koşullar altında bu tekstil boyasının rengini (400mg/L) 20 dakikada %61 giderebileceğini gösterdi. Sonuçlar, KSF'nin lakkaz üretimi için uygun olduğunu ve optimum koşullar altında bu funguslarla yüksek miktarda lakkaz elde edilebileceğini göstermektedir. En iyi uygulama şartlarını anlamak için ham lakkazların aktivite ve kararlılık profillerini belirlemek önemlidir.ANAHTAR KELİMELER: Katı substrat fermentasyonu, Funalia trogii, Ganoderma lucidum, Trametes versicolor, lignoselülozlu ham maddeler, ham lakkaz, renk giderimi Solid substrate fermentation (SSF) is a process occurring in the absence of free water, using natural substrates. This fermentation method which is an alternative method for biotechnologic processes uses lignocellulosic raw materials as solid substrates for laccase production with high activity and lower cost. Organisms utilize these solid substrates both as an attachment place and nutrition. Using lignocellulosic raw materials in bioprocesses may help to solve environmental problems.In this study, laccase production by newly isolated Funalia trogii, Ganoderma lucidum and Trametes versicolor was investigated during SSF process. The effect of different factors (solid substrate, temperature, pH, moisture content and inducers) on laccase production was tested. Among the tested lignocellulosic solid substrates wheat bran was determined the best solid substrate for laccase production. The effect of soy flour, tree leaves, yeast extract and copper on laccase production of fungi was also investigated. Wheat bran+soy flour medium supplemented with copper was the best medium for high laccase production. Optimum SSF conditions were 75% moisture content, 30°C and pH 5-6. SSF was also conducted using glass tray fermentor and high laccase activities as 22469±2622, 2008±826 and 2649±810 U/L were obtained for F.trogii, G.lucidum and T.versicolor, respectively. The effect of pH and temperature on crude laccase activity and stability, obtained from F.trogii, G.lucidum and T.versicolor grown on copper supplemented wheat bran+soy flour media were also tested. These crude laccases showed high activity especially at pH 2.5-3.5. They gave the highest activity in high temperatures. They were also detected as thermostable at high temperatures. Remazol Brilliant Blue R (RBBR) decolorization activity of crude laccase from G.lucidum showed that it could decolorize this textile dye (400 mg/L) as 61% within 20 minutes under optimal conditions. Results showed that, SSF has a potential for the laccase production and high amount of laccases could be obtained by these fungi under optimum conditions. It is important to determine the activity and stability profiles of these crude laccases for understanding the best application conditions.KEYWORDS: Solid substrate fermentation, Funalia trogii, Ganoderma lucidum, Trametes versicolor, lignocellulosic raw materials, crude laccase, dye decolorization 144

P oly 2-hydroxyethyl methacrylate-co-acrylic acid /diatomite hydrogel composite DHC materials were synthesized using in situ free radical addition polymerization technique. The effects of particle size and amount of diatomite were investigated on swelling properties such as the swelling degree SD , equilibrium swelling degree ESD and water retention WR of DHC. The particle size and amount of diatomite were not affected clearly in the swelling properties. The synthesized DHC with the particle size of -45μm and the amount of 5 wt % of diatomite showed the highest swelling properties. The SD g/g , WR % and ESD % values of hydrogel were increased up to 29.2, 45.5 and 96.7 from 1.1, 41.3 and 89.3 by adding diatomite into the structure of hydrogel, respectively. The hydrogel and DHC were characterized using Fourier transform infrared spectrometer FTIR and an optical microscope. Also, their thermal behavior was analyzed by differential scanning calorimeter DSC . The FTIR spectrums showed that diatomite incorporated into the hydrogel matrix at the high amount of diatomite. The DSC results indicated that the glass transition temperature Tg and melting temperature Tm of hydrogel increased with the addition of 2 wt % diatomite. The adsorption studies were performed using the hydrogel composite including 5 wt % of diatomite

WOS: 000453906100006, Conductive poly(o-toluidine)/kaolinite composite was synthesized via chemical polymerization of o-toluidine in the availability of kaolinite using ammonium persulfate as oxidizing agent. To investigate the use of the prepared conductive composite as humidity and temperature sensor, the effect of polymerization conditions such as HCl, o-toluidine and oxidant concentrations on the amount of conductive POT contained in the composite and the conductivity values of composites were investigated. It was found that the composites with the highest poly(o-toluidine) content (29.4%) and conductivity (8.3x10(-4) Scm(-1)) were obtained by 0.2 M ammonium persulfate, 0.4 M o-toluidine and 1 M hydrochloric acid for 2 hours of continuous polymerization at 20 degrees C. The resistivity values of pure poly(o-toluidine) and poly (o-toluidine)/kaolinite composite were monitored during heatingcooling cycles in the range of 0-100 degrees C. Changes in resistivity for pure poly(o-toluidine) and poly(o-toluidine)/kaolinite composite with humidity 30-90% were examined and humidity sensor behavior was determined. Characterization of the prepared composite was performed by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy techniques (SEM)., Turkish Scientific and Technical Research Organization (TUBITAK) [107M542], This work was supported by Turkish Scientific and Technical Research Organization (TUBITAK) project numbered as 107M542.

The preparation of poly(vinyl alcohol) (PVA) hydrogels was succeeded via the freeze-thawing (F/T) method by varying the synthesis parameter conditions. The swelling capacity and long-term stability of the hydrogels were determined as a function of time at pH 2.1, 5.5 and 7.4 and found to be mainly affected by the synthesis parameter conditions. These studies showed that the swelling ratio generally increased with a low number of F/T cycles (2 and 3), high freezing temperature (- 5 and - 16 degrees C) and freeze-dried of drying type for all three pH mediums. The dried hydrogels at room temperature were found to be more stable hydrogels. In addition, the drug release studies of salicylic acid as a drug model were investigated at pH 7.4 and displayed controlled release for 120 h. The release kinetic studies obtained from drug release data demonstrated that the PVA hydrogel fits well into the Higuchi model. The release mechanism of PVA hydrogel was also determined as super case II type. WOS:000702600200001 2-s2.0-85116300994