Immobilization of Streptomyces olivaceoviridis E-86 xylanase on Eudragit S-100 for xylo-oligosaccharide production

A 47 kDa xylanase (FXYN) from Streptomyces olivaceoviridis E-86 was immobilized on Eudragit S-100 and an immobilization efficiency of 90% was obtained. The optimum pH of the immobilized xylanase shifted from 5.8 to 6.3 while its optimum temperature moved from 60 to 65 degrees C. The immobilized enzyme also showed a higher thermal stability than the free xylanase. Only a marginal increase in the K-m values of free enzyme was observed upon immobilization. However, V-max values of the immobilized enzyme were 82-161% higher than those of the free xylanase. The immobilized xylanase was also evaluated for its application in hydrolyzing the corncob powder pre-treated with 2% NaOH solution for xylo-oligosaccharide production. The final extent of xylan hydrolysis using pre-treated corncob powder was 84% for the immobilized enzyme after 24 h of incubation at 55 degrees C. The immobilized xylanase retained 81% of its initial hydrolysis activity even after being recycled four times. Therefore, the immobilized xylanase is suitable to produce xylo-oligosaccahrides from corncob powder pre-treated with dilute alkaline solution. (c) 2005 Elsevier Ltd. All rights reserved.