Oyster Mushrooms Pleurotus ostreatus, P. pulmonarius, P. cornucopioides, P. eryngii
Oyster mushrooms contain all 8 essential amino acids, B vitamins, vitamin C, vitamin D2. They are relatively high in zinc, copper, potassium and iron. Secondary metabolites include sterols, lovastatin, GABA, ergothioneine, ketones, flavonoids, carotenoids and tricholomic acid.
In Traditional Chinese Medicine oyster mushrooms are an ingredient of Tendon Easing Powder. It is used to treat lumbago, numbed limbs, and tendon and blood vessel discomfort.
An HA ß-glucan in Oyster Mushrooms released by hot water extraction shows marked antitumor activity. In a laboratory study a water soluble extraction of fresh Oyster Mushroom showed significant cytotoxicity and apoptosis on human androgen-independent prostrate cancer cell lines. Oyster Mushroom sporocarps inhibit aromatase activity with potential for treating hormone sensitive cancers. In another laboratory study crude extract of Oyster Mushrooms Pleurotus pulmonarius was found to exhibit antioxidant, anti-inflammatory and antitumor activity. Methanol extracts were comparable to the drug Diclofenac, a non-steroidal anti-inflammatory used for mild pain relief, in their effect.
Pleuran, a ß-1-3glucan extracted from Oyster Mushrooms, given as a nutritional supplement with vitamin C has been shown to reduce respiratory tract infections in humans. It has also been shown to be effective in treating induced colitis in studies with rats.
Laboratory studies have shown various compounds extracted from Oyster Mushrooms, including novel proteins and laccase enzymes may prove useful in HIV treatment.
Lovastatin is a well known pharmacological agent for treating high cholesterol. Lovastatin-like compounds are found in oyster mushrooms, particularly in the mature gills. Extracts of Oyster Mushrooms stimulated the activity of SOD (Superoxide Dismutase), catalase and gluthione peroxidase and decreased VLDL (very low density lipoprotein) cholesterol levels. Plovastin is a standardised extract of Oyster Mushroom developed at the University of Haifa, Israel. It contains biologically active statins, which are known inhibitors of cholesterol in humans. Mevinolin, a fat lowering compound, has also been found in Oyster Mushrooms.
Remasan is a standardised product made from dried Oyster Mushrooms. Oral administration of Remasan was found, in a Finnish study, to cause warts to disappear and prevent their reappearance.
Oyster Mushroom products are commercially available as medicines for reducing cholesterol and as a nerve tonic, but not yet for antitumor, antibiotic or antiviral activity.