Laminaria Enzymolysis Products And Their Effects On Sea Cucumber Growth

Laminaria is a kind of rich algae resources along the coast of China. Because of its low costand high nutritional value, it is the ideal natural bait to sea cucumber. But nearly50%of polysac-charide in Laminaria make water ropiness, bacteria growing then inducing sea cucumber disease. Therefore, this study attempts to dispose Laminaria to single-cell powder and retain nutrition v-alue using biological enzymolysis technology, and broke polysaccharide down into oligosacchar-ides to inhibit the growth of bacteria and adjust the immunity of sea cucumber, which contribute-s to the development of sea cucumber bait with immune regulation function.This study use the enzyme produced by H0-5strain to degrade Laminaria. The bestconditions of the degradation are20℃,150r/min and24h. We use Double nitro salicylic acidmethod, thin-layer chromatography, sulfuric acid and phenol method to analyze theoligosaccharides. We find its average molecular weight is2846, average degree ofpolymerization is7and it is composed of four main components. After enzymolysis, we findtotal sugar of Laminaria is reduced by31.55%(0.97), protein increased by5%(0.32), crudefat, crude fiber and ash content increased significantly by109.63%(1.73),82.14%(0.50)and109.63%(1.10), respectively. The nutritional components K, Mg and Fe increased significantly.We study the effect of the degraded Laminaria on the sea cucumber by analyzing the effectof oligosaccharides and mud on the growth rate and nonspecific immunity mechanism in the seacucumber fed by oligosaccharides and mud with different proportion. The result showed, the olig-osaccharides and mud both can promote the growth of sea cucumber with a dose dependent.The best dose of oligosaccharides is10%and the growth rate of sea cucu-mber is76.60%(±2.49)after50days. The best dose of kelp mud is25%and the growth rate of sea cucumber is40.30%(±2.45)after50days. The oligosaccharides and kelp mud both can improve the resistance of seacucumber and the best dose of oligosaccharides is10%. The growth rate of sea cucumber is23.02%（±0.82）. The oligosaccharide can significantly improve the activity of SOD, CAT, ACP,AKP and reduce the level of MDA, so it can adjust the immunity of sea cucumber and protectthe body from oxidative damage.This study has established the way of degrading Laminaria by the enzyme, which gets oligo -saccharides and mud, then we analyze the nutrition composition of the mud. The degraded Lami-naria can adjust the activity of the enzyme associated with the immune competence inthe sea cucumber and enhance the growth and the cultivation of resilience of the sea cucumber.