Preparation method of high-content lentinan

The invention discloses a preparation method of high-content lentinan. The preparation method of the high-content lentinan comprises the following steps: baking a mushroom fruiting body at 50 DEG C to constant weight; slicing, adding distilled water to fully soak for 20-30 minutes according to the solid-liquid ratio of 1:20; adding trypsase to react for 4 hours, wherein the adding amount of the trypsase is 0.5-2%; carrying out enzyme denaturalixation on boiling water for 15-20 minutes; filtering at 10000rpm, centrifuging for 10-15 minutes to obtain supernatant; concentrating an extracting solution, concentrating the extracting solution according to the concentration ratio of 1:3; precipitating ethanol, and adding absolute ethyl alcohol to the concentrated solution until the mass percent of the final concentration of the ethanol achieves 60-70%; stewing over the night at 4 DEG C; centrifuging at 4000rpm for 15 minutes; stirring, suspending and washing the sediment by using ethanol of which the equidensity is 60-70%; centrifuging at 10000rpm for 10-15 minutes, so as to obtain the sediment; freezing and drying in vacuum; dissolving the sediment into distilled water of which the mass ratio is 1:5; removing residual ethanol in a water bath at 70-80 DEG C; freezing and drying in vacuum, so as to obtain a coarse lentinan product. By adopting the preparation method of the high-content lentinan, the polysaccharide content is improved, meanwhile, the viscosity of a freeze dried aquatic product is reduced, and drying is facilitated.