Abstract

Isolation and characterization of alkaline phospatase from the hepato pancreatic wastes of brown shrimp, Parapeneopsis stylifera

Author(s): Krishna Prasad Nooralabettu, Deepa Chandrashekar, Deepa Nambiar, Vikas Shetty, Prithviraj

Marine environment contains a large pool of diversified species adapted to a variety of habitat conditions and enzymes with unique properties for industrial usage can be recovered as by-product from fish processing wastes. Shrimp alkaline phosphatase (SAP) was isolated and purified to homogeneity from the hepatopancreatic wastes of brown shrimp (Parapenaeopsis stylifera). Alkaline phosphatase was extracted from the tissues by homogenization at 3000 rpm for 10 minutes, followed by centrifugation at 10000 rpm for 30 minutes, precipitation at 55% ammonium sulphate saturation level, and dialysis for 12 hours against tris buffer. Further purification was carried out by column chromatography through silica gel and DEAE-sephadex. Even though 37°C was the optimum temperature for catalytic activity, alkaline phosphatase retained 91% of its activity after incubation at 65°C for 15 minutes and 75% of its activity after incubation at 100°C for 15 minutes. Optimum pH for catalytic activity of alkaline phosphatase was 9. Catalytic activity of the shrimp alkaline phosphatase was enhanced by Ca2+ or Zn2+ at lower concentration, inhibited above 10mM concentration of Ca2+ or Zn2+, inhibited by increasing concentration of EDTA and K+, activated by Na+ and Mg2+, and reactivated the Ca2+ inhibited alkaline phosphatase by Mg2+.