Biochemical composition of the Australasian sea cucumber, Australostichopus mollis, from a nutritional point of view

Background Sea cucumbers are highly prized seafood in Asia, where the demand for them has increased dramatically in recent years. However, nutritional information is only available for only a few of the commercially traded species. Methods In this study, the biochemical composition of the sea cucumber Australostichopus mollis was evaluated in terms of the major functional components: collagen, amino acid and fatty acid content using standard analytical procedures. Results The collagen, mostly type I, formed a homogeneously clustered network constituting 1.4% of the wet weight of adult A. mollis which is lower than for some other species of sea cucumber. The collagen consisted of α1 and α2 chains (around 116 kDa), α chain dimers, β chains (around 212 kDa), and small amounts of γ components. The most abundant amino acids were glycine, alanine, threonine, serine and proline (lysine/arginine ratio of 0.1). Threonine was the most abundant essential amino acid, followed by methionine and valine, while glycine was the dominant non-essential amino acid. The sea cucumbers had a low lipid content (0.2 and 0.1% of wet weight for the viscera and body wall, respectively) which is below the range reported for most other species of sea cucumber. The lipid contained high levels of PUFA (54%) compared to MUFA (23%) and SFA (24%). The dominant PUFA was arachidonic acid in both the body wall and viscera, followed by eicosapentaenoic acid. Conclusions Overall, the Australasian sea cucumber has strong potential as a functional food due to its high levels of PUFA and essential amino acids, comparing favourably with the most commercially valuable sea cucumbers.