Sweet potatoes, also known as yams, white potatoes, sweet potatoes, and groundnuts, among other names. Sweet potatoes with a brown or black skin are contaminated with black rot fungus.
The toxins excreted by the black rot fungus contain ipomeamarone and ipomeamaronol, which make the sweet potatoes hard and bitter, and are highly toxic to the human liver. The biological activity of these toxins cannot be destroyed by boiling, steaming, or roasting. Therefore, eating sweet potatoes with black rot, whether raw or cooked, can cause poisoning. It is equally dangerous to feed them to livestock such as pigs and cattle.
Black rot sweet potato poisoning usually develops within 24 hours. The main symptoms include gastrointestinal symptoms such as nausea, vomiting, and diarrhea. In severe cases, high fever, headache, shortness of breath, confusion, convulsions, vomiting blood, coma, and even death may occur. There is currently no specific treatment for this disease. Therefore, sweet potatoes with black rot should not be eaten.