Antihypertensive effects of hydrolysates of wakame (Undaria pinnatifida) and their angiotensin-I-converting enzyme inhibitory activity.
OBJECTIVE
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.
Sato
Minoru
M
Laboratory of Marine Biochemistry, Graduate School of Agricultural Science, Tohoku University, Miyagi, Japan. msato@bios.tohoku.ac.jp
Oba
Takashi
T
Yamaguchi
Toshiyasu
T
Nakano
Toshiki
T
Kahara
Takashi
T
Funayama
Katsura
K
Kobayashi
Akio
A
Nakano
Takahisa
T
D000284:Administration, Oral; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use*; D000818:Animals; D000959:Antihypertensive Agents / Q000627:therapeutic use*; D001794:Blood Pressure / Q000187:drug effects; D004063:Digestion; D006868:Hydrolysis; D006973:Hypertension / Q000188:drug therapy*; D007700:Kinetics; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D012624:Seaweed / Q000737:chemistry*
D000806:Angiotensin-Converting Enzyme Inhibitors; D000959:Antihypertensive Agents