Abstract
This chapter deals with the promising bioactive compounds of marine
shellfish viz. crustaceans, molluscs, and echinoderms. Among the marine crustaceans,
the extracts of shrimps and crabs containing astaxanthin showed major bioactivities.
On the other hand, among molluscs, gastropods possessed the maximum number of
secondary metabolites and associated bioactivities compared to the bivalves and
cephalopods. Further, among echinoderms, the asteroids and holothurians showed
maximum number of secondary metabolites compared to their counterparts viz.
echinoids and crinoids.