Abstract: The present invention provides soy sauce that comprises significant amounts of peptides, and, in particular, hypotensive peptide Gly-Tyr and hypotensive peptide Ser-Tyr, exhibiting a high degree of angiotensin-I-converting enzyme-inhibitory activity and has hypotensive effects while containing no hypotensive agent. Target soy sauce is obtained by mixing soy sauce koji having protease activity of 20 to 300 U/g koji with an aqueous common salt solution and subjecting the mixture to heated digestion, followed by compression filtration. Target soy sauce with a good flavor is obtained by adding soy sauce lactic acid bacteria and soy sauce yeast cells to the moromi mash after heated digestion, and subjecting the resultant to fermentation and maturation, followed by compression filtration.

Abstract: To provide ACE inhibitory peptides which can effectively inhibit ACE by a small amount of ingestion and have no fear of causing side effects and which can be orally ingested easily during daily life by persons having high blood pressure, and compositions comprising the peptides. The peptides represented by the following structural formulae (1) to (9), and salts thereof are provided. (1) Asp-Arg-Pro, (2) Asn-Trp, (3) Val-Gly-Leu, (4) Ile-Gly-Val, (5) Gly-Val-Pro, (6) Ile-Pro-Tyr, (7) pyroGlu-Pro, (8) Tyr-Thr, (9) Pro-Trp.

Abstract: A fermented seasoning which does not have the bitterness specific to peptides and can be easily ingested orally, in spite of containing large amount of peptides is provided. Namely, a fermented seasoning obtained by adding salt water to an Aspergillus culture or a mixture of the Aspergillus culture with a plant-derived protein material and by controlling the leucine aminopeptidase-I activity in the moromi to be 1.0 U/ml or less, and also controlling the leucine aminopeptidase-II activity in the moromi to be 0.5 U/ml or less, within 10 days after the preparation.

Abstract: To provide ACE inhibitory peptides which can effectively inhibit ACE by a small amount of ingestion and have no fear of causing side effects and which can be orally ingested easily during daily life by persons having high blood pressure, and compositions comprising the peptides. The peptides represented by the following structural formulae (1) to (9), and salts thereof are provided.

Abstract: The present invention provides soy sauce that comprises significant amounts of peptides, and, in particular, hypotensive peptide Gly-Tyr and hypotensive peptide Ser-Tyr, exhibiting a high degree of angiotensin-I-converting enzyme-inhibitory activity and has hypotensive effects while containing no hypotensive agent. Target soy sauce is obtained by mixing soy sauce koji having protease activity of 20 to 300 U/g koji with an aqueous common salt solution and subjecting the mixture to heated digestion, followed by compression filtration. Target soy sauce with a good flavor is obtained by adding soy sauce lactic acid bacteria and soy sauce yeast cells to the moromi mash after heated digestion, and subjecting the resultant to fermentation and maturation, followed by compression filtration.

Abstract: To provide ACE inhibitory peptides which can effectively inhibit ACE by a small amount of ingestion and have no fear of causing side effects and which can be orally ingested easily during daily life by persons having high blood pressure, and compositions comprising the peptides. The peptides represented by the following structural formulae (1) to (9), and salts thereof are provided.

Abstract: A fermented seasoning which does not have the bitterness specific to peptides and can be easily ingested orally, in spite of containing large amount of peptides is provided. Namely, a fermented seasoning obtained by adding salt water to an Aspergillus culture or a mixture of the Aspergillus culture with a plant-derived protein material and by controlling the leucine aminopeptidase-I activity in the moromi to be 1.0 U/ml or less, and also controlling the leucine aminopeptidase-II activity to be 0.5 U/ml or less, within 10 days after the preparation.

Abstract: A low common salt soy sauce, which has good flavor, significantly suppresses elevation of blood pressure, prevents cardiac hypertrophy, and is also available as special nutritious food, is obtained. 1.0% to 10.0% by weight of potassium chloride and 0.1% to 5.0% by weight of ?-aminobutyric acid are added to a reduced common salt soy sauce, so as to obtain a low common salt soy sauce of issue. Otherwise, a KCl-containing low common slat soy sauce is obtained by: (1) a common production method of soy sauce, in which a mixed solution consisting of KCl and common salt is used as mother water; (2) a method of subjecting a soy sauce obtained using saline solution as mother water to electrodialysis, a membrane treatment, or the like, so as to eliminate common salt from the above soy sauce, and then adding KCl thereto; or other methods.

Abstract: A low common salt soy sauce, which has good flavor, significantly suppresses elevation of blood pressure, prevents cardiac hypertrophy, and is also available as special nutritious food, is obtained. 1.0% to 10.0% by weight of potassium chloride and 0.1% to 5.0% by weight of ?-aminobutyric acid are added to a reduced common salt soy sauce, so as to obtain a low common salt soy sauce of issue. Otherwise, a KCl-containing low common salt soy sauce is obtained by: (1) a common production method of soy sauce, in which a mixed solution consisting of KCl and common salt is used as mother water; (2) a method of subjecting a soy sauce obtained using saline solution as mother water to electrodialysis, a membrane treatment, or the like, so as to eliminate common salt from the above soy sauce, and then adding KCl thereto; or other methods.