Using the soybean protein isolate as the substrate, angiotensin converting enzyme (ACE) inhibitory activity and peptides content as evaluation indexes, the strain with high yield ACE inhibitor was screened. With the ACE and protein hydrolysis degree (DH) as evaluation indexes, the fermentation conditions for ACE inhibitor were optimized by single factor experiments. Bacillus subtilis BS90 with high ACE inhibitory activity was screened by microbiological fermentation. The optimum fermentation conditions were determined as liquid state fermentation, soy protein content 5％, initial pH 9.0, culture temperature 35 ℃ and time 40 h. Under the fermentation conditions, the DH and ACE inhibitory activity were up to 89.1％ and 81.8％, respectively, which was increased by 69.5％ and 13.4％ compared to that of before optimization. It laid a foundation for the separation and preparation of subsequent ACE inhibitory peptides.%以大豆分离蛋白为基质,以血管紧张素转化酶(ACE)抑制活性和多肽含量为评价指标,筛选高产ACE抑制剂的菌株,并以ACE和蛋白水解度(DH)为考察指标对其产ACE抑制剂的发酵条件进行单因素优化.通过微生物发酵法筛选出一株具有高ACE抑制活性的枯草芽孢杆菌(Bacillus subtilis)BS90.经单因素试验确定最优发酵条件为:采用液态发酵,大豆蛋白含量5％,初始pH值9.0,培养温度35 ℃,培养时间40 h.在此发酵条件下,DH和ACE抑制活性分别达到89.1％和81.8％,较优化前分别提高69.5％、13.4％.为后续ACE抑制肽的分离制备奠定了基础.
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