里氏木霉GXC木聚糖酶的研究*

研究了里氏木霉GXC产木聚糖酶的条件和酶学性质。结果表明，适宜产酶碳源为乳糖、甘露糖、棉子糖、木聚糖和麸皮，氮源为牛肉膏和酵母膏；产酶的最适初始pH为4.0，30℃培养60h。对以麸皮为碳源的培养液进行纯化的酶特性研究表明，木聚糖酶的最适反应温度为50℃，pH为5.5，该酶在pH5.0(7.0和40℃以下相对稳定。Fe3+和Mn2+对木聚糖酶有较大的促进作用，Cu～2+、Fe～2+和Ca～2+ 具有抑制作用。

STUDIES ON XYLANASE FROM STRAIN GXC OF TRICHODERMA REESEI

The condition of xylanase production of Trichoderma reesei GXC and enzyme properties were studied. The suitable carbon and nitrogen sources for xylanase production were lactose, mannose, raffinose, xylan, wheat bran , beef extract and yeast extraction. The optimal condition for enzyme production was initial pH 4.0, shaking at 30℃ for 60 h. Xylanase was purified from the culture supernatant in the medium with wheat bran as carbon source.The optimal temperature and pH for purified xylanase reaction were 50℃ and 5.5, respectively. Xylanase was stable at pH 5.0～7.0 and below 40℃. The xylanase activity was significantly stimulated by Fe～3+ and Mn～2+, and inhibited by Cu～2+, Fe～2+ and Ca～2+.