酒曲源曲霉的分离及其产蛋白酶条件优化

Screening of Aspergillus strains from Qu powder and optimization of production condition of protease

利用稀释平板法从曲样中分离获得4株曲霉1#、2#、3#和4#,将各菌株分别制米曲后测定酶活力,并通过正交实验及单因素实验确定蛋白酶发酵的培养基和最佳工艺条件。在优化的发酵培养基和发酵条件下(温度、培养时间、培养基起始pH、接种量),产蛋白酶活力分别达到:1#菌11545.7U/g,2#菌8240.4U/g,3#菌9146.0U/g,4#菌4527.7U/g。最后,将活力比较高的三株菌进行Biolog微生物系统鉴定,分别为栖土曲霉(Aspergillus terricola Marchal),寄生曲霉(Aspergillus parasiticus Speare)和杂色曲霉(Aspergillus versicolor)。

Aspergillus were isolated by streak plate method, four Aspergillus strains were obtained named 1^#、2^#、3^# and 4^#.The enzyme activity were examined for each strain by koji- making, and the optimal conditions for liquor production and fermentation was determined by orthogonal test and single factor.The producing capability under the optimum ferment culture and ferment condition were 1^# 11545.TU/g,2^# 8240.4U/g,3^# 9146.0U/g,4^# 4527.7U/g. The last,Biolog automated microbes identification system（ B iolog System）was used to identify as Aspergiflus terricola Marcha, Aspergillus parasiticus Speare and Aspergillus versicolor.