Eating green or sprouted potatoes
Introduction and description
Solanum, the nightshades, horsenettles and relatives, is a large and diverse genus of annual and perennial plants, including:
- The potato (Solanum tuberosum)
- Tomato (Solanum lycopersicum)
- Eggplant or aubergine (Solanum melongena)
- Black nightshade (Solanum nigrum )
- Bittersweet or Woody nightshade (Solanum Dulcamara)
Some of the plants in the Solanum family have the most wonderful common names, which give a good idea of their toxicity, for example, Five-minute Plant [which is presumably all you have before you conk out], "apple of Sodom” , Goat Apple, Poison Apple, "bitter-apple" , Devil's Tomato, Sticky Nightshade, fire-and-ice, and Devil's Fig.
Potatoes naturally produce solanine and chaconine, a related glycoalkaloid, as a defense mechanism against insects, disease, and predators.
Potato leaves, stems and shoots are naturally high in glycoalkaloids. This of course, is not normally a problem because we do not eat the leaves, or the stems or the shoots. Nor do we eat the fruits. But, a glykoalkaloid called Demissidine can occur in the tubers, in much smaller amounts - mostly in the skin.
Incorrect storage of tubers – in sunlight for example results in higher concentrations of the alkaloids – the green skin of a potato, for example, contains high concentrations of Demissidine, which also makes you very ill. It has ‘DNA modifying activities’ which is as ominous as it sounds. Some diseases, such as late blight, can dramatically increase the levels of glycoalkaloids present in the tuber of potatoes.
So by eating potatoes infected by blight, or eating potatoes which have green skins or which have started to sprout, we could be inadvertently setting ourselves up for a near death experience!