Optimization of Enzymatic Extraction of ACE Inhibitory Peptide from Rohu (Labeo rohita) Fish Waste using RSM

Background: Hypertension is one of the cardiovascular disease that kills people silently across the globe. It can be controlled, in one of the way, by ACE inhibitory peptide extracted from aquatic resources. Methods: Rohu (Labeo rohita) fish wastes were quantified for their anatomical yield; analyzed for their proximate composition and optimized the enzymatic extraction parameters for ACE inhibitory peptides. Response surface methodology with Box-Benhken Design (RSM-BBD) was used to optimize alcalase concentration (0.5-2% v/w), hydrolysis temperature (45-60°C), hydrolysis time (60-240 min.) and solid: liquid (S/L) ratio (0.2-1) to obtain rohu fish waste peptides. Results: More waste generated in smaller (49.4%) than medium and bigger (34.5%) fish. Quantum of edible flesh (59.06%) was followed by head (23.9%), trimmings (5.18%), scales (4.19%) and swim bladder (0.65%). However, protein content was highest in swim bladder (34.1%) followed by scales (22.9%), trimmings (18.7%) and head (17.1%). Alcalase concentration (1.08%, v/w), temperature (52.10°C), hydrolysis time (129.18 min) and S/L ratio (0.8:1) were found optimum for extraction ACE inhibitory peptide with DH, ACE inhibition and PY of 19.27%, 54.98% and 51.37% respectively. Results showed the potential of extracted ACE inhibitory peptide as ingredients in functional food.