黑曲霉mAn-1产木聚糖酶液体发酵工艺的研究

Liquid fermentation technology of xylanase-producing Aspergillus niger mAn-1

对高产木聚糖酶黑曲霉mAn-1的液体发酵工艺进行优化,以提高其生产木聚糖酶的能力。采用单因素轮换试验分别优选出最适碳源种类和氮源种类,通过2水平正交试验设计对影响产酶的8个培养基组成成分进行效应评价,选择具有显著效应的2个因素,并确定出最适培养基组成:玉米芯粉25g/L,麸皮粉25g/L,NH4NO3 5g/L,KCl 0.5g/L,K2HPO4 1g/L,MgSO4.7H2O 0.5g/L,微量元素液10mL,吐温-80 10mL,CaCO3 20g;采用响应面中心组合设计试验对发酵条件进行优化,得出接种种龄、接种量和装液量的最佳值分别为49.3h、14.38mL、138mL。以优化后的工艺进行发酵,黑曲霉mAn-1的木聚糖酶活力可达8244U/mL。

To optimize submerged fermentation conditions for a high xylanase-producing Aspergillus niger mAn-1 and improve the yield of the xy- lanase. Based on results of single factor experiments, the optimum kind of carbon and nitrogen sources were determined. Two statistically significant factors and optimum medium were determined through two-level orthogonal experiment with to evaluation of the effects of eight factors related to xylanase production. The culture medium were optimized as follows： corncob powder 25 g/L, wheat bran 25 g/L, NH4O3 5 g/L, KC10.5 g/L, K2HPO4 1 g/L, MgSO4·7H2O 0.5 g/L, Mandels 10 ml, Tween-80 10 ml, CaCO3 20 g. Factors affecting inoculation conditions were optimized using central composite designs and response surface methodology. The results showed that the optimum conditions for xylanase secretion was about seed of 49.3 h, inoculum 14.38 ml, addition of medium 138 ml medium in 500 ml erlenmeyer flasks. The xylanase activity was up to 8244 U/ml under the optimum conditions.