黑曲霉产菊粉酶菌株的选育及培养基优化

为获得高产菊粉酶的黑曲霉菌株,以Aspergillus niger YH-1为出发菌株,经过亚硝基胍(NTG)诱变,以高温高菊芋粉相结合的方式进行梯度驯化,选育出一株产菊粉酶菌株YH-3,并运用响应面实验方法对该菌株的培养基进行优化。确定了最佳培养基组成:菊芋粉25.2 g/L、豆饼粉40 g/L、蔗糖酯4.9 g/L、NaCl 5.5 g/L。发现内切菊粉酶活力(I)由60.9 U/mL提高到165.0 U/mL,比出发菌株提高了1.7倍。研究证明蔗糖酯对于黑曲霉YH-3发酵产菊粉酶是一种有效的促进剂。

Breeding of Aspergillus niger strain for producing inulinase and optimization of culture medium

In order to acquire a high-yield Aspergillus niger strain for producing inulinase,the original strain Aspergillus niger YH-1 was treated with N-methyl-N′-nitro-soguanidine （ NTG ） and domesticated by combining high temperature and Jerusalem artichoke powder, a inulinase production strain YH-3 was selected.The culture medium of YH-3 was optimized by response surface methodology.The results showed that the optimum culture medium components were determined：Jerusalem artichoke flour 25.2 g/L, soybean cake powder 40 g/L, sucrose ester 4.9 g/L and NaCl 5.5 g/L.Under the optimum conditions, the yield of inulinase was increased from 60.9 U/mL to 165.0 U/mL, increased 1.7 times compared with the starting strain.The research proved that sucrose ester was an effective accelerator for Aspergillus niger YH-3 producting inulinase.