| 摘要 |
NEW MATERIAL:Xylanase WII selected from xylanase W2 and xylanase W4 and having the following properties. Action and substrate specificity, active to break the beta-1,4-xylo side bond of xylan and xylo-oligosaccharide to form xylose and xylobiose; optimum pH range, pH6-7; stable pH range, pH4.5-10 (at 45 deg.C for 60 min); optimum working temperature, 60-70 deg.C at pH6-7; thermal stability, stable up to 60 deg.C by the treatment for 10min. USE:Production of xylose useful as a food, etc., from xylan existing in wood, etc. It is resistant to heat and alkali. PREPARATION:Microbial cells are removed from a cultured product of a microbial strain capable of producing xylanase WII [e.g., Bacillus sp. No.W2 (FERM P-7221)] and the obtained clear liquid is added with ammonium sulfate to precipitate the enzyme. The precipitated enzyme is dehydrated and dried and the obtained crude power of enzyme is dissolved in a 0.05M tris-HCL buffer solution of pH7.2 and separated and purified with DEAE-cellulose and sephadex G-100. |
