Journal of Pure and Applied MicrobiologyVol. 8 No. 6

Purification and Biochemical Characterization of Xylanase from Sclerotium rolfsii

Tarek A. A. Moussa*, Neveen M. Khalil, Dalia M. I. Ali and Fatma A. Mostafa

Department of Botany and Microbiology, Faculty of Science, Cairo University, Giza 12613, Egypt.

Received on 23 October 2014 and accepted on 28 November 2014

 

ABSTRACT

Xylanases have received great attention in the development of environment-friendly technologies in the paper and pulp industry. Their use could greatly improve the overall lignocellulosic materials for the generation of liquid fuels and chemicals. Fungi are widely used as xylanase producers and are generally considered as more potent producers of xylanases than bacteria and yeasts. After the purification steps, a purified xylanase enzyme was obtained with purification fold 14.3. The SDS-PAGE for enzyme protein gave a single band at about 32 kDa. The zymogram technique was performed to ensure that the purified enzyme was xylanase using 0.1% brichwood xylan. The optimum reaction temperatures of the xylanase enzyme were 50?C and 60?C, while optimum pH values were 5.0 and 6.0. From the above we can conclude that the optimum temperature lies between 50-60?C and optimum pH lies between pH 5.0 and 60. The activity of xylanase enzyme was stable at 50?C and 60?C, and pH 4.0 and 5.0 for at least 2 hrs. Mg2+ was the only metal, which enhanced the xylanase activity, while Cu2+ and Hg2+ showed the highest inhibitory effects on the activity of xylanase. The metal chelating agent EDTA had moderately inhibitory effect on enzyme activity.

Keywords : Xylanase, SDS-PAGE, zymogram, inhibitors, Sclerotium rolfsii.