Value added utilization of sea cucumber (Cucumaria frondosa) by-products: collagen and protein hydrolysates

Oceans cover approximately 70% of the world's surface and the abundance of marine organisms in these oceans has been known to provide numerous compounds with curative powers. During the past decade, several scientific research initiatives have explored various species of sea cucumber. The most common sea cucumber species found in northwest Atlantic is Cucumaria frondosa. Fresh sea cucumbers comprise body wall, meat, flowers, gonads, respiratory tracts and intestines and these are composed of 82-92.6% moisture, 2.5-12.8% protein, 0.1-0.9% lipid, 1.5-4.3% minerals and 0.2-2.0% carbohydrate. In addition, sea cucumber contains various high value nutraceuticals and pharmaceuticals with biological properties, including collagen, gelatin, protein, amino acids and other bioactive molecules. Meat is the most marketable product of this Atlantic species. The present study was focused on utilization of sea cucumber processing by-products by developing a bioprocessing strategy for the extraction of collagen from sea cucumber body wall and producing protein hydrolysates from internal organs, flower, body wall and muscle using readily available commercial enzymes. Furthermore, antioxidant capacity of the protein hydrolysates was determined using in vitro methods such as reducing power, 2, 2-diphenyl-1-picrylhydrazyl (DPPH) and hydroxyl radical scavenging as well as metal chelating abilities. Among all hydrolysates prepared from different sea cucumber by-products, hydrolysates produced from the flower exhibited the highest reducing power, metal chelation and high scavenging for DPPH and hydroxyl radicals. This study expands the existing knowledge for production of value-added nutraceuticals from Atlantic species, thereby maximizing the sustainability and economic viability of the seafood industry.