Shiitake Polysaccharide Identity
Shiitake polysaccharide powder is made from the fruiting body of Lentinula edodes (Berk.) Pegler, the cultivated shiitake mushroom grown on hardwood logs or sawdust blocks. The mushroom itself is the source, and mycelial culture broth and substrate are not part of this material. The name lentinan refers to one purified glucan from this mushroom: a β-(1→3)-glucan with β-(1→6) branches at regular intervals along the chain.
Fungal cell walls are built from chitin, β-glucans and mannoproteins, and the mushroom also stores carbohydrate as glycogen, an α-glucan, with trehalose and mannitol as small soluble sugars. Hot-water extraction takes out the soluble and swellable polymers together with these small molecules, and ethanol precipitation then favors the large polymers.
The result is a fraction in which branched β-glucan is one important component but not the only one. Shiitake polysaccharide powder is a polysaccharide extract, so it should not be read as pure lentinan. Chitin stays largely in the insoluble residue, and the lentinan name in the product title describes the glucan family and not a purity.
Three related shiitake products are specified differently. Shiitake Mushroom Powder is the milled whole mushroom, Shiitake Cap Powder is the milled cap, and Shiitake Mushroom Extract Powder is a ratio extract.












