小麦面粉中阿拉伯木聚糖酶解性质的研究(I)——水溶性阿拉伯木聚糖的酶解

Enzymatic Degradation of Arabinoxylan from Wheat Flour (I) Degradation of Water-extractable Arabinoxylan

用水作溶剂从“特一粉”中提取水溶性阿拉伯木聚糖 (WEAX)进行酶解试验 :在较高的木聚糖酶水平下酶解 2h(酶 底物为 1.0× 10 - 3) ,WEAX被显著降解 ,粘度下降 80 % ;低的酶用量条件下 (酶 底物为 0 .1× 10 - 3)降解速率明显降低 ,延长作用时间至 4h ,粘度仅下降 45 %。由WEAX及其酶解产物的凝胶过滤图谱可知 :WEAX具有多分散性 ,分子量分布范围从几万到几十万 ;WEAX中有一部分蛋白质是和多糖结合在一起的 。

Water-extractable arabinoxylan (WEAX) isolated from wheat flour was treated with xylanase in vitro.At a high ratio of enzyme to WEAX (1.0×10 -3 )for 2h ,WEAX was markedly degraded.The specific viscosity of the solution was reduced by 80%.At a low enzyme dose (1.0×10 -3 g/g),the rate of degradation slowed down,the fall in viscosity was only 45% for 4h.WEAX and its enzymic degraded products fractionated by the gel filtration chromatogratphy indicated that the molecular weight of WEAX widely ranged from 10kD to 100kD,and that there were some WEAX associated with proteins,which would be more difficult to degrade.