We purified a novel angiotensin-I converting enzyme (ACE) inhibitor from fish sauce Ishiru prepared from squid, and identified it as the tripeptide Leu-Ala-Arg (LAR). IC₅₀ of this ACE inhibitor was 2.5 μM, demonstrating high potency among peptides previously purified from fish sauces. Moreover, LAR acted as an antihypertensive peptide, reducing systolic blood pressure in spontaneously hypertensive rats.

Objective: The purpose of this study was to confirm the effect of feeding Okara fermented by Bacillus coagulans on cecum microflora in rat. Method: Three groups of SD rat of 8 weeks old were used in the experiment. The experimental animals were fed control diet, 2% okara diet, 2% fermented okara diet in each group for two weeks. The experimental diet and water were provided ad libitum. Food intake was measured every day. After 24 hours fast, we performed drawing blood with heparin after the experimental period. After drawing blood, several organs were removed for measuring their weight. In addition, we removed cecum after drawing blood about each three groups and studied their microflora. We also measured about plasma albumin, ALT, AST, ALP, LDH, total cholesterol, triacylglycerol, glucose, and cytokine level. Result: Bifidobacteria of cecum and blood IFN-g levels significantly increased in the fermented okara group. The total cholesterol level in blood significantly decreased. Conclusion: Okara fermented by Bacillus coagulans had an influence on not only intestinal microflora but also the immune system in rat, suggesting that the fermented okara can expect development as functional materials.