Yamamoto N, Akino A, Takano T
Research and Development Center, Calpis Food Industry Co., Ltd., Ebisu-Tokyo, Japan.
J Dairy Sci. 1994 Apr;77(4):917-22. doi: 10.3168/jds.S0022-0302(94)77026-0.
Peptides derived from alpha s1- and beta-caseins by the Lactobacillus helveticus CP790 proteinase were investigated for their inhibitory activities against angiotensin I-converting enzyme. The antihypertensive effect of casein hydrolysates in strain SHR spontaneously hypertensive rats was also investigated. Both alpha s1- and beta-casein hydrolysates inhibited this enzyme. Some of these peptides showed enzyme inhibitory activity, and one of them from beta-casein inhibited the enzyme greatly; the concentration of an angiotensin I-converting enzyme inhibitor needed to inhibit 50% of the enzyme activity was 4 microM. The hydrolysate of casein demonstrated antihypertensive activity in spontaneously hypertensive rats at an orally administered dosage of 15 mg/kg of body weight. MILK fermented with L. helveticus CP790, containing about .3% peptides, also showed antihypertensive activity in SHR rats with 5 ml/kg of body weight (15 mg of peptide/kg); however, the milk fermented with L. helveticus CP791, a variant defective for proteinase activity, did not show this activity. Results suggested that the peptides liberated from casein by the proteinase in the culture medium showed antihypertensive effect in SHR rats.
研究了瑞士乳杆菌CP790蛋白酶从αs1-酪蛋白和β-酪蛋白衍生出的肽对血管紧张素I转化酶的抑制活性。还研究了酪蛋白水解物对自发性高血压大鼠（SHR）的降压作用。αs1-酪蛋白和β-酪蛋白水解物均能抑制这种酶。其中一些肽表现出酶抑制活性，β-酪蛋白中的一种肽对该酶有很强的抑制作用；抑制50%酶活性所需的血管紧张素I转化酶抑制剂浓度为4 microM。酪蛋白水解物以15 mg/kg体重的口服剂量在自发性高血压大鼠中表现出降压活性。用瑞士乳杆菌CP790发酵的牛奶，含有约0.3%的肽，以5 ml/kg体重（15 mg肽/kg）的剂量在SHR大鼠中也表现出降压活性；然而，用蛋白酶活性缺陷的变体瑞士乳杆菌CP791发酵的牛奶没有显示出这种活性。结果表明，培养基中的蛋白酶从酪蛋白释放的肽在SHR大鼠中具有降压作用。
