<正>使用硫酸铵分级沉淀、SephadexG 25凝胶色谱脱盐、DEAE SephadexA 50和SP SephadexC 50离子交换色谱等分离纯化技术,从里氏木霉(Trichodermareesei)RutC 30培养液中分离出木聚糖酶组分,再经SephadexG 100凝胶过滤色谱进一步分离纯化,得到2个纯木聚糖酶组分A和组分B。经SDS PAGE鉴定两组分为单带,相对分子质量分别为20300和13500。组分A的最适反应条件为45℃、pH4.5,在pH3.0～5.5很稳定,酶解产物主要是低聚木糖,只含少量木糖;组分B的最适反应条件为55℃、pH5.5,酶解产物全部是低聚木糖。

Two parts of xylanases(Part A and Part B) were separated and purified from a culture filtrate of Trichoderma reesei Rut C30 by ammonium sulfate precipitation,followed by DEAESephadex A50 and SPSephadex C50 column chromatography.Part A and Part B were further purified to homogeneity by Sephadex G100 column chromatography.The molecular weights of Part A and Part B were estimated to be 20 300 and 13 500 by SDSPAGE chromatography.The optimal reaction conditions for Part A and Part B were at 45 ℃,pH 4.5,and at 55 ℃,pH 5.5,respectively.Part A was stable in a pH range from 3.0 to 5.5,while Part B was stable in a pH range from 3.5 to 7.5.The major products of enzymatic hydrolysis with Part A were xylooligosacchrides,with a small amount of xylose,while that with Part B were merely xylooligosacchrides.