Nicotianamine content in various beans and its inhibition activity of angiotensin-I converting enzyme

Soybean is known to inhibit activity of angiotensin-I converting enzyme (ACE). The inhibitory substance is nicotianamine. However, little research has been conducted on beans aside from soybeans. We studied the inhibition of ACE and nicotianamine content of 41 different beans. Among these beans, particularly effective ACE inhibitory activity was found in Kinusaya (fresh), Goku-shousuzumamedaizu, and Greenpeace (fresh) beans. The amount of nicotianamine for every 100 g dry powder was the highest in Kinusaya fresh), followed by Benishibori and Green soybean bean (fresh). For comparison of the genera with nicotianamine content, nicotianamine content in Vigna was significantly less than that in Pisum (p <0.05), and Phaseolus and Glycine (p<0.001). The strength of ACE inhibition of beans was correlated to the amount of nicotianamine content. This shows that ACE inhibition of beans is attributable to nicotianamine content.