Oyster mushroom (Hiratake, píng gū, 平菇) is a famous edible mushroom that has been eaten as a delicacy around the world for centuries. This mushroom lives up to its name, in that the taste and texture are similar to oysters. Most people find it is one of the tastiest of the normal mushrooms; adding it to eggs, soups and sauces. It has been noted that people who consumed it on a regular basis have lower cholesterol.

Consumption of Oyster Mushrooms lowers blood concentrations of triglycerides, cholesterol and oxidized LDL due to a naturally occurring statin drug Lovastatin.^1,2,3  This effect has been compared to the use of Lipitor™ and Crestor™ in function. Lovastatin was the first statin drug officially accepted for use. Other statins are contraindicated in alcoholism, pregnancy and in cases of liver disease, but not the use of Oyster mushroom.

This mushroom nutritionally speaking falls between high-grade vegetables and meat, including all essential amino acids and other nutrients. It contains up to 27% protein, 38% carbohydrates with only 1% fat. Oyster mushrooms also contain considerable amounts of thiamine, riboflavin, folic acid, sterols, vitamin D₂ and D₄  gamma ergosterols, carotenoids, and bioflavonoids. The levels of copper and zinc are higher than in any other cultivated mushroom.

Oyster mushrooms have been shown to modulate immune function, used as an immune prophylactic.⁴ This mushroom showed an antioxidant and cyclooxygenase-inhibiting effect.⁵ Both in-vivo and in-vitro studies show effects against breast and colon cancers due to beta-glucans.^6,7,8

This delicious mushroom can be made into an instant tea by adding hot water to ½ to 1 tablespoon (depending on strength desired) of mushroom powder. It can be added to blender drinks, sauces, and soups, or sprinkled on food.

Caution: About 5 – 10% of Europeans and North Americans have mild allergic reactions to Oyster mushrooms, in its fruiting body form, with spores intact.⁹ This has not been reported with the powdered extract, but if mushroom allergies are suspected, start off slowly and build up the dose to see if there is a reaction.

Other uses:

One US environmental company called Ecovative Design is using the mycelium along with petroleum substrate to create an expanded polystyrene (Styrofoam-like) packing, insulating and building material. Oyster mushrooms have been found to absorb and digest oil spills and other petroleum products.¹⁰ It has been proposed for use in areas like the Alberta Tar sands project.

Dosage:

 Oyster Mushroom Super Food: 50:50 combination of 1:1 and 4:1 powdered extract. Use ½ teaspoon to 1 tablespoon daily to lower blood lipids.

References:

1. Inga Schneider, Gaby Kressel, Annette Meyer, et al; Lipid lowering effects of oyster mushroom (Pleurotus ostreatus) in humans; Journal of Functional Foods Volume 3, Issue 1, Jan 2011, Pages 17-24
2. Rop O, Mlcek J, Jurikova T. (2009). “Beta-glucans in higher fungi and their health effects”. Nutrition Reviews 67 (11): 624–31
3. Gunde-Cimerman N, Cimerman A. (Mar 1995). “Pleurotus fruiting bodies contain the inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme A reductase-lovastatin.”. Exp Mycol. 19 (1): 1–6
4. Nozaki, Hirofumi; Itonori, Saki; Sugita, Mutsumi; et al (2008); “Mushroom acidic glycosphingolipid induction of cytokine secretion from murine T cells and proliferation of NK1.1 α/β TCR-double positive cells in vitro”. Biochemical and Biophysical Research Communications 373 (3): 435–9
5. Inga Schneider, Gaby Kressel, Annette Meyer, et al; ibid
6. Jedinak A, Sliva D (December 2008). “Pleurotus ostreatus inhibits proliferation of human breast and colon cancer cells through p53-dependent as well as p53-independent pathway”. International Journal of Oncology 33 (6): 1307–13.
7. Zusman I, Reifen R, Livni O (1997). “Role of apoptosis, proliferating cell nuclear antigen and p53 protein in chemically induced colon cancer in rats fed corncob fiber treated with the fungus Pleurotus ostreatus”. Anticancer Research 17 (3C): 2105–13.
8. Bobek P, Galbavy S (2001). “Effect of pleuran (beta-glucan from Pleurotus ostreatus) on the antioxidant status of the organism and on dimethylhydrazine-induced precancerous lesions in rat colon”. British Journal of Biomedical Science 58 (3): 164–8.
9. Horner WE, Levetin E, Lehrer SB; Basidiospore allergen release: elution from intact spores; J Allergy Clin Immunol. 1993 Aug;92(2):306-12.

10. http://www.thisoldhouse.com/toh/article/0,,20153687,00.html accessed Jan 06, 2012