Studies on Phenolase Enzymes in Prawns 1. The Distribution and Physical Properties of Phenolases in Penaid Prawns

Abstract

The distribution of phenolases in certain species of Penaeid
prawns has been studied. Attempts were made to locate the regions
of maximum enzyme activity in the prawns. The relative dopase
activity has been examined in extracts from head, tail, shell with
cuticles and muscle. The head juice and tail extracts were found to
register very high order of enzymic activity. Metapenaeus affinis,
Metapenaeus monoceros and Penaeus indicus record comparatively
higher enzymic activity than Parapenaeopsis stylifera and Metapenaeus
dobsoni, No definite relationship has been found between the
relative activity of the enzyme and size grade at least in one species
examined. Experiments were done to determine the pH optima of
the enzyme and the influence of pH on its deactivation. Exposure to
higher temperatures upto 55C was shown to activate the crude
enzyme considerably. The possible implications of the observations
have been discussed.