多轮定向酶解木聚糖制备木低聚糖的研究

研究了多轮定向酶解未水解木聚糖的低聚糖组成、得率、适宜的用酶量及重复利用未水解底物的次数。结果表明 ,随着轮数的增加 ,木聚糖被降解的难度越来越大 ,而且木低聚糖的组成、平均聚合度也发生变化。采用逐步加大用酶量同时适当缩短酶解时间的方法 ,不仅能够获得较高的木低聚糖得率 ,而且可以改善酶解液的澄清度。但在实际生产中 ,重复利用未水解木聚糖的轮数应以 2～ 3轮为宜

PREPARATION OF XYLO-OLIGOSACCHARIDES BY MULTIPLE-RUN SELECTIVE ENZYMATIC HYDROLYSIS OF XYLAN

Composition,yield of oligosaccharides,suitable enzyme dosage and the times of reusing the unhydrolyzed xylan were studied during preparation of xylo oligosaccharides by multiple run selective enzymatic hydrolysis.The results indicated that xylan became more difficult to be hydrolyzed with increased times of reuse.Moreover,the composition and degree of polymerization of oligosaccharides were changed.By adopting re hydrolysis of the residue with increased enzyme dosage and reduced hydrolytic time,high yield of xylo oligosaccharides could be obtained along with improved transparence of supernatant liquid of enzymatic hydrolysate.Practically,it was appropriate to reuse the unhydrolyzed xylan for two or three times.