关键词: 活性碳层析, 固定化, 海栖热袍菌, 木聚糖酶, 木二糖

Abstract: The thermostable recombinant xylanase B (XynB) from Thermotoga maritima MSB8 was immobilized on nikel-chelated Eupergit C 250L,and then used to hydrolyze the autohydrolysis explosion liquor of corncob (AELC) for continuous production of xylooligosaccharides,especially xylobiose. The immobilized XynB had a good operation stability and still retained its relative activity of 92% after 15 cycles of hydrolysis at 90 ℃. The immobilized XynB retained 83.6% of its initial hydrolysis activity even after 168 hours of hydrolysis reaction and demonstrated a half-life time of 577.6 hours (24 days) for continuous hydrolysis. HPLC analysis showed that xylobiose (49.8%) and xylose (22.6%) are the main products during continuous hydrolysis. Xylobiose was absorbed on an activated charcoal column and eluted with a linear gradient of ethanol to obtain xylobiose with 84.7% yield,and 97.2% purity. Therefore,the immobilized XynB can be applied for the efficient production of xylobiose from AELC.

Key words: activated charcoal column chromatography, immobilization, Thermotoga maritim, axylanase, xylobiose