Auricularia polytricha, a flattened ear-shaped mushroom used in Chinese cooking, produces an anticoagulant effect. In 1980, a U.S. case of “Szechwan Purpura” was reported in the New England Journal of Medicine. A 32-year-old U.S. researcher (during an experiment using his own blood platelets for clotting) found after some 50 trials one morning that his platelets would not agglutinate or release serotonin on exposure to epinephrine. (211) On physical examination, he had a few small bruises on the legs. Tests, not requiring platelets, were normal. He and his co-workers were able to trace the aspirin-like effect back to Mo-er (the Mandarin name for Auricularia polytricha). This mushroom inhibited platelet response in the researcher and other volunteers for 3-24 days. Like aspirin (another inhibitor of platelets), this mushroom should not be ingested prior to surgery or by patients with poor blood clotting.

Auricularia polytricha photo © Tom Duffy

Western physicians thus became aware that Auricularia polytricha inhibits the tiny blood platelets that initiate blood clotting in the small vessels and capillaries of the body. This mushroom is a dark rubbery, irregular ear-like fungus known in Asian markets as “wood ears”. This mushroom is especially common on trees along canals and waterways in the damp, fertile province of Szechwan. Like the discovery of penicillin, it occurred in the course of a different investigation.

Cookbooks commonly confuse the fleshier Auricularia polytricha with the smaller and thinnerAuricularia auricularia, which has no effect on platelets and which Cantonese cooking uses in its contrast of textures. The more spicily sauced cuisines of Szechwan and Hunan use the thickerAuricularia polytricha more for soaking up their richer sauces than for texture.

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