Collagen as the Major Edible Component of Sea Cucumber ( <i>Stichopus japonicus</i> )

Abstract

ABSTRACT: The body wall collagen of an edible sea cucumber, Stichopus japonicus , was studied with respect to its chemical composition and subunit structure. About 70% of the total body wall protein was accounted for by highly insoluble collagen fibers. The disaggregation with β‐mercaptoethanol, 0.1 M NaOH treatment, and limited pepsin digestion of these collagen fibers resulted in complete solubilization. The solubilized collagen was isolated and characterized; it had 2 distinct subunits, αl and α2, which formed (α1) 2 α2 heterotrimers and was rich in glutamic acid when compared with other fibrillar collagens. The unique textural properties of cooked sea cucumber seem to be due to thermal denaturation of the insoluble collagen fibers.