木聚糖酶高产微生物的筛选和鉴定

Isolation and Identification of Prolific Microorganism in Xylanase

利用蔗渣木聚糖为惟一碳源 ,从甘蔗根部泥土样品中分离得到一株产木聚糖酶活力较高的菌株 ,经形态、生理及生化鉴定 ,初步确定为蜂房芽孢杆菌 ;同时研究了碳源、氮源对该菌产木聚糖酶的影响 .结果表明 ,其最适碳源为木聚糖 ,最适氮源为酵母浸膏和硝酸铵的混合氮源 ;在装料 10 0mL的 2 5 0mL三角摇瓶中于 32℃、12 0rpm振荡培养 40～ 44h后 ,发酵液中木聚糖酶活力高达 3839.5Iu/mL 。

A strain of microorganism, which is prolific in the production of xylanase, was isolated from the soil of sugarcane root system, and identified as Bacillus alvei. Further research showed that, for the xylanase production of Bacillus alvei,the optimal carbon source is xylan, and nitrogen source is mixture of ammonium nitrate and yeast extract. Culturing was carried out in Shake Flasks (250 mL) containing 100 mL medium which is composed of 0.6% NaCl, 0.2% yeast extract, 0.15% NH 4NO 3, 0.2% K 2HPO 4, 0.01% CaCl 2, 0.01% MgSO 4, 0.01% FeSO 4 and 0.05% xylan at initial pH7.0, all flasks were incubated for 44 h in an shaker (120 rpm, 32 ℃), the xylanase activity of culture filtrate came up to 3 839.5 Iu/mL.