Antihypertensive and antioxidant properties of five different protein hydrolysates produced from Indian white Shrimp (Penaeus indicus) by-products

In these days press of hypertension and free radicals is the cause of disease in industrial countries. Medicines by antihypertensive and antioxidant properties could inhibit these diseases. In this study Shrimp byproducts were hydrolyzed with 5 different enzymes: Alcalase, Pepsin, α- Chimotrypcin, Neutras and Flavourzyme. Angiotensin-I converting enzyme (ACE-Iinhibitory activity), DPPH free radical scavenging activity (antioxidant properties) and amino acid composition measured in the hydrolysates. With Alcalase ,the highest degree of hydrolysis (DH) and nitrogen recovery was 64.2±1.4% and 75±1.6%, respectively. Antioxidant activity was 47.1±1.2% with Alcalase and 45.1±0.3% with α-Chimotrypcin. The maximum ACE-I inhibitory activity was seen in the Alcalase hydrolysates and α-Chimotrypcin hydrolysates by IC50=0.85±0.02 mg/ml and 0.9±0.04 mg/ml, respectively. ACE-Inhibition activity of hydrolysates after ingestion by all enzymes was stable. Amino acid composition showed high hydrophobic residues content. In conclusion, Shrimp by-products Protein hydrolysates produced by Alcalase and α-Chimotrypcin have good ACE-Iinhibitory activity and antioxidant properties and could be used in human nutrition as bioactive peptide.