Miyoshi S, Ishikawa H, Kaneko T, Fukui F, Tanaka H, Maruyama S
Research and Development Center, Showa Sangyo Co., Ltd., Chiba, Japan.
Agric Biol Chem. 1991 May;55(5):1313-8.
Peptides that inhibit angiotensin-converting enzyme (ACE) were isolated from alpha-zein hydrolysate prepared with thermolysin. Their chemical structures were identified by Edman degradation and fast-atom bombardment mass spectrometry. Most of them were found to be tripeptides such as Leu-Arg-Pro, Leu-Ser-Pro, and Leu-Gln-Pro, having IC50 values of 0.27, 1.7, and 1.9 microM, respectively. These peptides were synthesized by a solid phase procedure and had similar ACE inhibitory activities as the isolated inhibitors. The hypotensive activity of Leu-Arg-Pro on spontaneously hypertensive rats was also investigated, with the result that the the blood pressure decreased by 15 mmHg after a 30 mg/kg intravenous injection.
