Angiotensin I-converting enzyme inhibitor from Grifola frondosa

To investigate the hypotensive compounds From edible mushroom, extracts from 10 fruit bodies of mushrooms were screened for the inhibitory activity against angiotensin I converting enzyme (ACE). The most potent ACE inhibitory activity (58.7%) was detected in a cold water extract of Grifola frondosn, with an IC50 of 0.95 mg. The ACE inhibitory activities of the cold and hot water extracts increased as the extraction time increased, but decreased slightly 15 h and 90 min, respectively, after extraction. After the purification of ACE inhibitory peptides with acetone fractionation and column chromatography, we obtained an active fraction with an IC50 Of 0.13 mg and a yield of 0.7%. The purified inhibitor showed competitive inhibition on ACE and this peptide maintained inhibitory activity even after digestion by intestinal proteases. (C) 2001 Elsevier Science Ltd. All rights reserved.