Angiotensin I-Converting Enzyme Inhibitors in Autolysates of Squid Liver and Mantle Muscle

Autolysis of squid liver and mantle muscle homogenates, and blends of both, each yielded inhibitory activity toward the angiotensin I-converting enzyme. The inhibitory activity and the amount of solubilized protein in each of these autolysates were examined over a period of 24 h. Inhibitory peptides were isolated from the mixed autolysate, their structures (IC50) being Tyr-Ala-Leu-Pro-His-Ala (9.8 microM) and Gly-Tyr-Ala-Leu-Pro-His-Ala (27.3 microM).