米曲霉产中性蛋白酶的适宜条件

Suitable Conditions for the Production of Neutral Proteinase by Aspengillus oryzae

研究了米曲霉产蛋白酶的分布,优化了米曲霉产中性蛋白酶的适宜培养条件以及培养基的最优组成。研究发现米曲霉产中性蛋白酶的能力为最强。米曲霉产中性蛋白酶的适宜培养条件为:m(麸皮)∶m(豆粕粉)=4∶1,水的质量分数为60%,培养基中各无机盐质量分数为:KNO30.2%,MgSO40.05%,Na2HPO40.13%,pH值为6.0,接种量为每10 g培养基接种1.0×108个孢子,最佳培养温度为30℃,最佳培养时间为48 h。在此培养条件下,最高酶活力达3 999.2 U.g-1。

The kinds of protease from Aspergilluas oryzae, and the suitable conditions for the production of neutral protease are studied. The results indicate that the productivity of neutral protease is the highest. The suitable composition （ % ） of the medium is as follows ： wheat bran 32, bean cake powder 8, water 60% , KNO3 0.2% , MgSO4 0.05% , Na2HPO4 0.13% , pH 6.0. The optimal cultural temperature is 30℃, culture duration 48 hours, and inoculating 1.0 × 10^8 spores each gram medium. Under the optimal conditions, the neutral protease activity is as high as 3 999.2 U · g^-1.