Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Türkiye
Tezin Onay Tarihi: 2004
Tezin Dili: İngilizce
Öğrenci: Hümeyra Bahçeci
Danışman: GÜZİN CANDAN GÜLTEKİN
Özet:In this study, 11 bacterial isolates from Salt Lake,Turkey were identified by using fatty acid methyl ester (FAME) analysis. They were screened for production of industrially important enzymes xylanase, cellulase, a-amylase and protease. These enzymes were characterized in terms of enzyme activity, stability, optimum temperature and optimum pH. One of the isolates was identified as Bacillus pumilus, and two of them were identified as Bacillus subtilis. Other isolates were determined to be Bacillus licheniformis. All the isolates were determined to produce xylanase. Optimum temperatures and optimum pH values of xylanases were 50-55 °C and pH 7.0-8.0. Xylanases were quite stable up to pH 8.0 and 70 °C. Isolates were not significant cellulase producers. Four of the isolates did not produce any cellulase enzyme and the rest produced negligible amounts of cellulase. Therefore, xylanases from the isolates were promising for pulp and paper industry, which requires cellulase free and stable xylanases. All the isolates produced appreciable quantities of a-amylase. Optimum temperatures and optimum pH values of a-amylases 60-80 °C and pH 7.0-8.0. a-Amylases were quite stable up to pH 9.0 and 80 °C. a-Amylases from the isolates were promising for starch processing industry, which requires a-amylases stable at high temperatures and for detergent industry, which requires a-amylases stable at alkaline pH values. Considerable protease productions were achieved by all the isolates. TTG 2 was the best protease producer with 271 U/ml. Optimum temperatures and optimum pH values of proteases were 50-60 °C and pH 7.0-7.4. Proteases were quite stable up to pH 9.0 and 80 °C. Proteases from the isolates were promising for detergent and leather industry, in which proteases must be stable at alkaline pH values.