对浓香型大曲中蛋白酶产生细菌进行分离,并对其最适产酶条件进行研究。采用酪素培养基,从大曲中分离出5株产蛋白酶菌株,筛选出酶活力最高的菌株,其酶活为53.40 U/mL。以小麦为固体培养基,从pH值、培养基水分含量、碳源添加量、氮源添加量、接种量、培养温度和培养时间等方面研究此菌株的最适产酶条件。结果表明,在水分含量65%、初始pH6.0、蔗糖添加量6%、硫酸铵添加量1%、接种量12%、温度40℃,培养时间5 d的条件下,其酶活可达262.18 U/mL,为菌种复筛时的4.91倍。%Protease-producing Bacillus strains were isolated from Luzhou-flavor Daqu and its optimum protease-producing conditions were inves- tigated. 5 protease-producing Bacillus strains were isolated from Daqu by use of casein agar culture mediums and the strain with the highest pro- tease activity （53.40 U/mL） was screened out. Then wheat was used as solid culture medium to investigate the optimum protease-producing condi- tions and the optimum conditions were summed up as follows： moisture content was 65 %, initial pH value was 6.0, sugar addition level was 6 %, ammonium sulfate addition level was 1%, yeast inoculating quantity was 12 %, culture temperature was at 40 ℃, and culture time was 5 d. Under the above conditions, the produced protease activity could reach up to 262.18 U/mL, 4.91 times of that before secondary screening.
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