title: Angiotensin I-converting enzyme inhibitory peptides derived from wakame (Undaria pinnatifida) and their antihypertensive effect in spontaneously hypertensive rats.
abstract: Seven kinds of angiotensin I-converting enzyme (ACE) inhibitory peptides were isolated from the hydrolysates of wakame (Undaria pinnatifida) by Protease S "Amano" (from Bacillus stearothermophilus) by using three-step high-performance liquid chromatography (HPLC) on a reverse-phase column. These peptides were identified by amino acid composition analysis, sequence analysis, and liquid chromatography-mass spectrometry (LC-MS), as Val-Tyr (IC(50) = 35.2 microM), Ile-Tyr (6.1 microM), Ala-Trp (18.8 microM), Phe-Tyr (42.3 microM), Val-Trp (3.3 microM), Ile-Trp (1.5 microM), and Leu-Trp (23.6 microM). These peptides have resistance against gastrointestinal proteases in vitro. Each peptide was determined to have an antihypertensive effect after a single oral administration in spontaneously hypertensive rats (SHR). Among them, the blood pressure significantly decreased by Val-Tyr, Ile-Tyr, Phe-Tyr, and Ile-Trp in a dose of 1 mg/kg of body weight (BW). The present study showed that antihypertensive effect in the hydrolysates of wakame by Protease S "Amano" was attributed to these peptides.
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification* / Q000627:therapeutic use*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D006973:Hypertension / Q000188:drug therapy*; D008297:Male; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification / Q000627:therapeutic use; D051381:Rats; D011918:Rats, Inbred SHR; D012624:Seaweed / Q000737:chemistry*; D020539:Sequence Analysis, Protein
chemical_list: D000596:Amino Acids; D000806:Angiotensin-Converting Enzyme Inhibitors; D010455:Peptides