May 20/Journal of Technology & Science -- "Natto is a popular traditional Japanese food made by fermenting steamed soybeans with Bacillus subtilis natto. It has long been thought that natto is effective in preventing hypertension," researchers in Tsukuba, Japan, report.
"But there have not been any reports demonstrating in vivo antihypertensive effects of natto. In this study, we demonstrate for the first time the antihypertensive activity of natto in vivo. We determined optimal conditions for producing natto with the highest angiotensin I converting enzyme (ACE) inhibitory activity. An ACE inhibitor partially purified from natto was orally administered as a single dose (1mg, 10mg and 100mg/kg body weight) in spontaneously hypertensive rats, and then their blood pressure was measured five times every hour after administration. The administration of the inhibitor, even at the lowest dose, resulted in a significant decrease in blood pressure," wrote S. Ibe and colleagues, University of Tsukuba.