米曲霉双菌株组合制曲对产蛋白酶的影响

Effects of Combination Koji Making of Two Strains of Aspergillus oryzae on Proteases System

通过对2株米曲霉菌株进行组合制曲培养,以中性蛋白酶、氨肽酶为指标,得到制曲时间短、制曲中性蛋白酶和氨肽酶活性高的组合比例。将2株米曲霉菌株按合适比例进行组合制曲培养,检测中性蛋白酶和氨肽酶活力。在p H 7.2、30℃条件下对单菌株进行制曲培养,CICC2339和CICC2066菌株中性蛋白酶活力在42 h分别达到1187.7 U/g和830.8 U/g,其氨肽酶活力分别在42 h和60 h达到最高值93.2 U/m L和201.4 U/m L,最优组合菌株A6B4制曲42 h中性蛋白酶和氨肽酶活力最高分别达到1 366.8 U/g和148.7 U/m L,其中性蛋白酶和氨肽酶活力都较单菌株制曲具有优势。2株米曲霉菌株组合制曲能够缩短制曲时间,提高中性蛋白酶和氨肽酶活力,这些研究结果为米曲霉在食品发酵上的进一步了解提供帮助。

Two stains of Aspergillus oryzae were selected in combinated of koji making,in order to shorten koji making time and increase activity of neutral protease and aminopeptidase.The two strains of Aspergillus oryzae were combinated by appropriate proportion during koji making.The activity of neutral protease and aminopeptidase were determined.Single strain koji was cultivated for pH 7.2,30℃.The neutral protease activity of CICC2339 and CICC2066 were reached 1 187.7 U/g and 830.8 U/g on 42 h respectively,the aminopeptidase were reached 93.2 U/mL and 201.4 U/mL on 42 h and 60 h respectively.The highest activity of neutral protease and aminopeptidase of optimal combination A6B4 were reached 1 366.8 U/g and 148.7 U/mL on 42 h respectively,which had advantages than single strain.The combination could shorten koji making time,increase the activity of neutral protease and aminopeptidase.These results provided some assistance to the further understanding of Aspergillus oryzae in the food fermentation.