Properties and antihypertensive effect of ACE inhibitory peptides from oyster on spontaneously hypertensive rats
ZHANG Ke-jia， ZHANG Sheng-nan， QI Yan-xia， ZHAO Qian-cheng， LI Zhi-bo
College of Food Science and Engineering, Key Laboratory of Aquatic Product Processing and Utilization of Liaoning Province, Dalian Ocean University, Dalian 116023, China
Abstract: The anti-digestive capacity, emulsifying activity, emulsifying stability, water absorption, oil absorption and solubility were investigated in ACE inhibitory oyster peptides with molecular weight less than 3000 from oysterCrassostreagigas prepared by desalting, secondary enzymatic hydrolysis, and ultrafiltration and the effect of food-borne natural marine ACE inhibitory peptides on blood pressure in vivo was studied in spontaneously hypertensive rats (SHR) by intragastric administration. The results showed that the oyster peptide powder prepared by secondary enzymatic hydrolysis method had polypeptide content of 66.7%, sugar content of 18.2%, and ash content of 6.31%, indicating that the prepared oyster ACE inhibitory peptide showed high purity, with 44.28% of essential amino acids including 17 perfective amino acid compositions and 14.17% hydrophobic amino acids. Oyster ACE inhibitory peptides had good state in terms of digestion stability， stronger oil absorption capacity than water absorption capacity, and good solubility at different pH (6-10) and temperature (50-90 ℃). The animal test showed that the minimal systolic blood pressure(SBP)[(161.56±16.63)mm Hg] was observed in SHR exposed to intragastric administration on the twenty-first days after intragastric administration of ACE inhibitory peptides of oysters,significantly lower than that in the control group(P<0.05)afterwards. The findings indicated that oyster ACE inhibitory peptide has a good antihypertensive effect in the body, with stable effect, which can be developed and utilized as a marine natural active peptide.
2018, Vol. 33 
