Valorization of Fish Viscera for Crude Proteases Production and Its Use in Bioactive Protein Hydrolysate Preparation

• Published in: Waste and biomass valorization 2018-10, Vol.9 (10), p.1735-1746
• Main Authors: Murthy, L. Narasimha, Phadke, Girija G., Unnikrishnan, Parvathy, Annamalai, Jeyakumari, Joshy, Chalil George, Zynudheen, Abubacker Aliyamveetil, Ravishankar, Chandragiri Nagarajarao
• Format: Article
• Language: English
• Subjects: Acetone; Ammonium; Ammonium sulfate; Antioxidants; Chelation; Chemical precipitation; Engineering; Environment; Environmental Engineering/Biotechnology; Enzymes; Ethanol; Euthynnus affinis; Euthynnus alletteratus; Foaming; Free radicals; Industrial Pollution Prevention; Original Paper; Papain; Properties (attributes); Proteins; Regression models; Renewable and Green Energy; Response surface methodology; Saturation; Sulfates; Tilapia; Tyrosine; Viscera; Waste Management/Waste Technology
• ISSN: 1877-2641; 1877-265X
• DOI: 10.1007/s12649-017-9962-5

Increasing environmental pollution and limited biological resources has emphasized the need for better utilization of fish processing waste. In the present study, visceral proteases from little tuna ( Euthynnus affinis ), catla ( Catla catla ) and tilapia ( Oreochromis mossambicus ) belonging to different habitats using acetone, ethanol and ammonium sulfate fractional precipitation were isolated and characterized. Enzymes precipitated from little tuna and tilapia exhibited higher specific activity at 40% saturation for ammonium sulfate fractional precipitation and the specific activities were 18.19 and 13.67 U/mg for little tuna and tilapia enzymes, respectively. Enzymes precipitated from catla reported higher specific activity of 8.32 U/mg at 60% saturation for ammonium sulfate fractional precipitation. Acetone precipitated fraction exhibited higher recovery for all crude enzymes studied. The effect of different combinations of crude tuna visceral waste enzyme and papain enzyme on hydrolysate properties was optimized using response surface methodology. Second order response surface regression model was used to explain the total variability in terms of quadratic and interaction effects of combination enzyme concentration on the properties of croaker protein hydrolysate with a significant R 2 value for protein content (0.92), tyrosine content (0.99), degree of hydrolysis (0.99), DPPH free radical scavenging activity (0.97), ferric reducing antioxidant power (0.93), metal chelating activity (0.88), foaming capacity (0.92) and foam stability (0.88). Based on the desirability score, papain at 0.81% concentration and crude tuna visceral protease at 4.36% was found to be optimal for achieving desired properties of croaker protein hydrolysate.