About Sea Cucumbers
Sea cucumbers are marine invertebrates that have gained more and more recognition among researchers in recent decades, they provide high-value nutrition and have multiple health benefits and therapeutic uses.
A high amount of good-quality protein in sea cucumber is linked with beneficial effects on stimulating immune system  and maintaining serum lipid levels . Sea cucumber protein is rich in glycine, glutamic acid and arginine which can stimulate the activation and proliferation of immune cells to enhance cell immunity . Collagen, the major protein in sea cucumbers, is recognized as a valued component in the connective tissues. A sea cucumber protein has been reported to significantly reduce the systolic blood pressure and diastolic blood pressure of renal hypertensive rats, which indicates an antihypertensive effect of sea cucumber protein by oral administration .
Sea cucumber-derived chondroitin sulfate can be exploited as a nutraceutical to ease joint-pain and arthritis . Researchers found that about 3 g/day serving of the dried sea cucumbers is medicinally effective in reducing arthralgia to a significant level . Sulfated polysaccharides from sea cucumber also exhibit antiviral activity against human immunodeficiency virus (HIV) infection .
Another important class of compounds from sea cucumber is saponins, triterpene glycosides, who have remarkable functions with anticancer and antitumor activities . Sea cucumber saponins have also displayed a wide spectrum of biological effects such as hypolipidemic activity, improvement of non-alcoholic fatty liver, inhibition of fat accumulation, anti-hyperuricemia, promotion of bone marrow hematopoiesis, antihypertension, etc. .
Polyunsaturated fatty acids (PUFA) are the dominant lipids found in sea cucumbers . Lipids in our species are dominated by eicosapentaenoic acid (EPA, C20:5n-3), ranging from 43.2 to 56.7% of the total fatty acids, and Docosahexaenoic acid (DHA, C22:6n-3) is present of 2.0-5.8% . EPA-enriched sea cucumber lipids exhibit potential neuroprotective effects by virtue of its antioxidant activity, suggesting an efficient and novel strategy to explore novel drugs or functional food for neuronprotection and cognitive improvement .
Considerable amounts of phenolics and free radical scavengers have also been determined in sea cucumbers . Therefore, the studies on the high-value components and bioactives as well as the multiple biological and therapeutic properties of sea cucumbers have shown great opportunity to develop their potential uses for functional foods and nutraceuticals.