Distribution and Chemoenzymatic Removal of Heavy Metals in Sea Cucumber Acaudina leucoprocta

Abstract

Sea cucumbers are traditional marine food in Asian countries. In this work, the chemical elements accumulated in sea cucumber Acaudina leucoprocta from the East China Sea were measured and analyzed. The contents of Zn, Mn, Cu, As, Pb, Cd and Cr increased with the increase of weight of A. leucoprocta. The levels of Pb and As in all the examined individuals were higher than the maximum residue limits (MRLs) permitted in foodstuffs. The metals were found to be selectively distributed in the body compartments of A. leucoprocta. The highest contents of heavy metals As, Pb were found in intestines and body wall, while the lowest in anus and internal organ. An efficient chemoenzymic method by combining proteolytic enzymatic hydrolysis with citric acid soaking was established to remove the heavy metals in sea cucumber A. leucoprocta. The concentrations of both As and Pb were decreased to below 0.5 mg kg⁻¹ in all the samples.