【摘要】 从土壤中分离出一株产普鲁兰酶的菌株 ,初步鉴定为芽孢杆菌 ,通过紫外及 EMS多次诱变及筛选 ,酶活从 1.6 u/ m L提高到 5.4 u/ m L。在此基础上对产酶条件进行了优化 ,酶活有了较大提高 ,最高产酶水平达 8.8u/ m L。初步研究了酶的性质 ,酶反应的最适温度和 p H分别为 75℃和 4 .6 ,在 55℃反应条件下 ,酶在p H4 .0～ 8.0范围内活性稳定。更多还原

【Abstract】 A strain producing pullulanase was isolated from soil and mutated by UV and EMS with the increase of pullulanase activity from 1.6 to 5.4 u/mL. The fermentation conditions and medium were studied and optimized. The enzyme activity can reach 8.8 u/mL under the optimal fermentation conditions and medium. The optimal pH and temperature for enzyme are 4.6 and 75℃ respectively. It shows a high stabiliby during pH4.0～8.0 at 55℃.更多还原