An Antihypertensive Peptide from Tilapia Gelatin Diminishes Free Radical Formation in Murine Microglial Cells

A peptide possessing antihypertensive activity was purified from Nile tilapia (Oreochromis niloticus) gelatin using alcalase, Pronase E, pepsin, and trypsin. Among them, the alcalase hydrolysate exhibited the highest angiotensin converting enzyme (ACE) inhibitory activity. Therefore, it was further analyzed, and a potent ACE inhibitory peptide of DPALATEPDPMPF (1382 Da) was separated and purified. In addition, the protective effect of the purified peptide against free radical-induced cellular and DNA damage in murine microglial cells (BV-2) was determined. These results suggest that the peptide isolated from Nile tilapia (O. niloticus) gelatin acts as a candidate against hypertension and oxidative stress and could be used in health-functional foods.