Angiotensin I‐converting enzyme inhibitory peptides produced from tuna cooking juice hydrolysate by continuous enzymatic membrane reactor

Abstract

Angiotensin I-converting enzyme (ACE) inhibitory peptides were derived from tuna cooking juice (TCJ) hydrolysis by alcalase in the continuous enzymatic membrane reactor (cEMR) coupling with 1kDa MWCO membrane. The permeated sample from cEMR for 510min of hydrolysis was purified by size exclusion chromatography in Sephadex G-25 column. A fraction exhibited the highest ACE inhibitory activity was further separated by RP-HPLC, resulting two fractions showed highest ACE inhibitory activities. The molecular weight (MW) and amino acid sequences of peptides from both fractions were determined using LC-MS/MS. Two potential ACE inhibitory peptides were obtained and showed molecular weight of 959.46 and 1,141.29Da. PRACTICAL APPLICATIONS: Tuna cooking juice (TCJ) usually was either used as protein source of feed meal or directly discharged to wastewater treatment system. However, it contains water-soluble proteins in a group of sarcoplasmic protein, which is small water-soluble proteins and easily hydrolyzed to small peptides. In this study, the active peptides, angiotensin I-converting enzyme inhibitory peptides (MW of 959.46 and 1,141.29Da), obtained from TCJ hydrolysate and identified by LC-MS/MS would be a beneficial ingredient for nutraceuticals and functional food against hypertension.