Sourced from China.
King Oyster mushrooms are a species of the Pleurotus family of mushrooms, and related to regular Oyster mushrooms. They have a large stem that confers a relatively 'meaty' or 'hearty' flavor (Umami) and are seen as a medicinal mushroom.
Oyster mushroom (Pleurotus ostreatus) is such a mushroom which is used both as food and medicine to ensure the fitness of body. It contains protein, carbohydrates, fat, fiber, water, different kinds of vitamins and minerals as well as secondary metabolites.