Comparative Study on Precipitation Techniques for Protease Isolation and Purification from Labeo rohita Viscera

Precipitation techniques play a vital role in the industrial extraction of enzymes. The present study aimed to extract the proteases from the viscera of Labeo rohita (commonly called Rohu) and to compare the precipitation techniques for the isolation and purification of the enzyme. The enzyme is usually discarded as tons of waste during processing. Hence, a trial has been carried out to isolate the protease enzymes from viscera of the freshwater fish Labeo rohita. The proteases were precipitated with ammonium sulfate, ethanol, and acetone. Acetone precipitation was found to be the best option for the recovery of enzymes (54%) from the viscera of Rohu, and two caseinolytic protease bands were shown in the zymogram. The precipitates with highest proteolytic activity were further subjected to dialysis, and their molecular weight was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE).