Antihypertensive effects of hydrolysates of wakame (Undaria pinnatifida) and their angiotensin-I-converting enzyme inhibitory activity

Ann Nutr Metab. 2002;46(6):259-67. doi: 10.1159/000066495.


Aim: The angiotensin-I-converting enzyme (ACE) inhibitory and antihypertensive activities of wakame hydrolysates have been investigated in several studies.

Methods: Wakame (Undaria pinnatifida) was hydrolyzed using 17 kinds of proteases and the inhibitory activity of the hydrolysates for ACE was measured. Of these hydrolysates 4 with potent ACE inhibitory activity were administered singly and orally to spontaneously hypertensive rats (SHR).

Results: The systolic blood pressure of SHR decreased significantly after single oral administration of protease S 'Amano' and proleather FG-F hydrolysates (10 mg protein/kg body weight). In a long-term feeding experiment, 7-week-old SHR were fed standard chow supplemented with protease S 'Amano'-derived wakame hydrolysates for 10 weeks. In SHR fed the 1 and 0.1% wakame hydrolysates, elevation of systolic blood pressure was still significantly suppressed for 7 weeks.

Conclusions: The hydrolysates derived from wakame by protease S 'Amano' have a powerful ACE-inhibitory activity (IC(50) = 86 microg protein/ml) and were effective in spite of their slight bitterness as 'physiologically functional food' with antihypertensive activity.

MeSH terms

  • Administration, Oral
  • Angiotensin-Converting Enzyme Inhibitors / therapeutic use*
  • Animals
  • Antihypertensive Agents / therapeutic use*
  • Blood Pressure / drug effects
  • Digestion
  • Hydrolysis
  • Hypertension / drug therapy*
  • Kinetics
  • Male
  • Rats
  • Rats, Inbred SHR
  • Seaweed / chemistry*


  • Angiotensin-Converting Enzyme Inhibitors
  • Antihypertensive Agents