Identification of angiotensin I-converting enzyme inhibitory peptides derived from salmon muscle and their antihypertensive effect

ABSTRACT:   The salmon peptide digested from salmon muscle showed a strong inhibitory activity against the angiotensin I-converting enzyme (ACE). The antihypertensive effect of the salmon peptide on spontaneously hypertensive rats (SHR) was examined. After the single intravenous administration of the salmon peptide at a dose of 30 mg/kg body weight, the systolic blood pressure (SBP) was significantly reduced against the control. Further, a double-blind, placebo-controlled, parallel-group study determined the efficacy of the salmon peptide in mild hypertensive subjects. The SBP, after a 1.0 g of salmon peptide intake, was significantly reduced at 4 weeks after the intake, and 2 weeks after the intake finished, compared to the value before ingestion. Bioassay-guided separation of the salmon peptide, using a combination of column chromatographic techniques, led to the identification of 20 active di- and tri-peptides, including Ile-Val-Phe and Phe-Ile-Ala as two new ACE inhibitory tripeptides. Ile-Trp had the strongest ACE inhibitory activity (IC₅₀ = 1.2 μM) in vitro , and contributed 5.2% to the total ACE inhibitory activity. The salmon peptide and Ile-Trp showed a digestive resistance by in vitro assay, which mimicked the digestive organ, and had no affinity for factors related to blood pressure regulation, except for the ACE inhibitory activity.     

Biodiversity and rarity distributions of native freshwater fish in an agricultural landscape: the importance of β diversity between and within water‐body types

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Detection and monitoring of ongoing aseismic slip in the Tokai region,central Japan

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The relationship between the snowmelt flood and the establishment of non‐native brown trout (Salmo trutta) in streams of the Chitose River,Hokkaido, northern Japan

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Morphological study of the transition of haematopoietic sites in the developing mouse during the peri-natal period

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Retinoids induce growth inhibition and apoptosis in mast cell tumor cell lines

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Antimicrobial resistance in Escherichia coli isolated from brown rats and house shrews in markets,Bogor, Indonesia

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