About Pleurotus tuber-regium (Fr.) Singer
Pleurotus tuber-regium, commonly known as the king tuber mushroom, is an edible gilled fungus native to the tropics of Africa, Asia, and Australasia. It has been confirmed to be a distinct species incapable of cross-breeding, and is phylogenetically separated from other Pleurotus species. P. tuber-regium is a saprotroph that grows on dead wood, including Daniellia trees in Africa. As the fungus consumes the wood, it produces a sclerotium, or storage tuber, either inside the decaying wood or in the underlying soil. These sclerotia are round, dark brown with white interiors, and can grow up to 30 cm wide. Fruiting bodies of the fungus then emerge from the sclerotium. Both the sclerotium and the fruiting bodies are edible. In addition to being saprotrophic, P. tuber-regium is also nematophagous, catching nematodes by paralyzing them with a toxin. P. tuber-regium has a history of economic importance in Africa as food and as a medicinal mushroom. Industrial cultivation is not common yet, but studies show that P. tuber-regium can be grown on organic wastes including corn, sawdust, and cardboard. Mycelial growth takes place between 15 °C and 40 °C, with the optimum growth rate occurring at 35 °C. A recent study found that polysaccharides from P. tuber-regium are able to delay the progression of diabetes and associated complications in rats with insulin resistance. P. tuber-regium can also degrade polyethylene film.
