Lentinan

Scientific Name(s): Lentinula edodes (Berk.) Pegler.
Common Name(s): Forest mushroom, Hua gu, Pasania fungus, Selected Vegetables, Shiitake, Snake butter, Sun's Soup

Medically reviewed by Drugs.com. Last updated on Jun 21, 2021.

Clinical Overview

Use

Lentinan is used widely in Japan and China as an adjuvant to cancer chemotherapy. It is also used for upregulating the immune system; however, the number of quality clinical trials and studies published in English language, peer-reviewed journals is limited.

Dosing

The isolated polysaccharide lentinan from shiitake culture has been used intravenously (IV) at doses of 2 to 10 mg on a weekly schedule as adjunctive therapy for HIV as well as for cancer, primarily in Japan. Oral shiitake extract was used in a trial for the treatment of prostate cancer at 8 g/day for 6 months.

Contraindications

Contraindications have not yet been identified.

Pregnancy/Lactation

Information regarding safety and efficacy in pregnancy and lactation is lacking.

Interactions

None reported.

Adverse Reactions

Clinical trials report few adverse events at normal dosages. Case reports exist of allergic/contact dermatitis, asthma, rhinitis, and hypersensitivity pneumonitis in shiitake workers. Shiitake dermatitis has been described as a reaction to the ingestion of raw or partially cooked mushrooms and may be a toxic reaction to lentinan. Photosensitivity reactions have also been reported. Anaphylaxis, granulocytopenia, and elevated liver enzymes were reported after rapid (10 minutes) IV infusion in an HIV trial.

Toxicology

The shiitake mushroom is edible and has generally not been associated with toxicity. In a study in mice, high-dose shiitake resulted in increases in plasma bilirubin and plasma creatine kinase.

Scientific Family

• Tricholomataceae

Botany

Lentinan is a polysaccharide derived from the vegetative parts of the edible Japanese shiitake mushroom. It is the cell wall constituent extracted from the fruiting bodies or mycelium of L. edodes. The light, amber fungi are found on fallen broad-leaf trees, such as chestnut, beech, or mulberry. They have decurrent, even, or ragged gills, a stem, and are covered with delicate white flocking. Shiitake mushrooms are commonly sold in food markets in Asia and are now widely available in the United States, Canada, and Europe.1 Synonyms include Cortinellus edodes, Armillaria edodes, Cortinellus shiitake, and Tricholomopsis edodes.

History

Shiitake has been recognized in Japan and China as a food and medicine for thousands of years. Lentinan was isolated from edible shiitake mushrooms used in traditional Asian cooking and herbal medicine. Extracts of these mushrooms are now being incorporated into over-the-counter dietary supplements designed to improve the immune system.1

Chemistry

The shiitake mushroom contains starch, fiber, chitin, and high amounts of protein.2 Lentinan is a water-soluble, high molecular weight polysaccharide in a triple helix structure, containing only glucose molecules with mostly (1-3)-beta-D-glucan linkages in the regularly branched main chain with 2 beta (1,6)-D-glucopyranoside branchings for every 5 beta-(1,3)-glucopyranoside linear linkages.1, 3 Lentinan, which is thermolabile4 is found in very low concentrations in fresh shiitake mushrooms (approximately 0.02%); at least 5 additional polysaccharides have been isolated from L. edodes.5

Other constituents of interest found in th...