Partial purification of polyphenoloxidase of black tiger shrimp (Penaeus monodon) from Indonesian waters

Abstract

Shrimps are a very important resource all over the world because of their high market value. Their post-mortem discoloration (blackspot) is one of the serious problems occuring in crustaceans and become an issue for the industry. Biochemical properties analysis of PPO from black tiger shrimp had been conducted, but information of partial purification techniques of the PPO of the shrimp from Indonesian waters had not yet been reported. The study aimed is to partial purifying the enzyme polyphenoloxidase (PPO) from black tiger shrimp (Penaeus monodon) responsible for blackspots discoloration. Extraction, precipitation with ammonium sulphates, partial purification, and determination of molecular weight were conducted. Precipitation showed best concentration to obtain the highest specific activity was using ammonium sulfate at 70% saturation. Four hours was the best dialysis periode. Polyphenoloxidase from carapace of black tiger shrimp was purified to 1.64-fold with Sephadex G-150 gel filtration chromatography. Activity staining of the PPO showed that the enzyme consisted of two isoform with the apparent molecular weight of 258.29 kDa and 222.05 kDa.