Pleurotus ostreatus, the oyster mushroom, is a common edible mushroom. It was first cultivated in Germany as a subsistence measure during World War I and is now grown commercially around the world for food. However, the first documented cultivation was by Kaufert There is some question about the name Pleurotus corticatus, but no question he cultivated an oyster mushroom. It is related to the similarly cultivated "king oyster mushroom". Oyster mushrooms can also be used industrially for mycoremediation purposes. The oyster mushroom may be considered a medicinal mushroom, since it contains statins such as lovastatin which work to reduce cholesterol.[
The oyster mushroom is widespread in many temperate and subtropical forests throughout the world, although it is absent from the Pacific Northwest of North America, being replaced by P. pulmonarius and P. populinus. It is a saprotroph that acts as a primary decomposer of wood, especially deciduous trees, and beech trees in particular. It is a white-rot wood-decay fungus. The oyster mushroom is one of the few known carnivorous mushrooms. Its mycelia can kill and digest nematodes, which is believed to be a way in which the mushroom obtains nitrogen. The standard oyster mushroom can grow in many places, but some other related species, such as the branched oyster mushroom, grow only on trees.
The oyster mushroom is frequently used in Japanese, Korean and Chinese cookery as a delicacy: it is frequently served on its own as soup, sometimes stuffed, or in stir-fry recipes with soy sauce. Oyster mushrooms are sometimes made into a sauce, used in Asian cooking, which is similar to oyster sauce. The mushroom's taste has been described as a mild with a slight odor similar to anise. The oyster mushroom is best when picked young; as the mushroom ages, the flesh becomes tough and the flavor becomes acrid and unpleasant. Oysters mushrooms are widely cultivated and used in Kerala, India; a wide variety of dishes are prepared from them. Oysters mushrooms are mainly cultivated in large clear polythene bags with buns of hay layered in the bags, and spores sown between these layers. Oyster mushrooms contain small amounts of arabitol, a sugar alcohol, which may cause gastrointestinal upset in some people.