Cyanogenic glycosides are present in a number of food plants and seeds. Hydrogen cyanide is released from the cyanogenic glycosides when fresh plant material is macerated as in chewing, which allows enzymes and cyanogenic glycosides to come together, releasing hydrogen cyanide. Cassava, an important source of carbohydrate for people in Africa and South America, is detoxified by chopping and grinding in running water prior to preparation.1
Cyanide is one of the most potent, rapidly acting, poisons known. Cyanides inhibit the oxidative processes of cells causing them to die very quickly. Because the body rapidly detoxifies cyanide, an adult human can withstand 50-60 ppm for an hour without serious consequences. However, exposure to concentrations of 200-500 ppm for 30 minutes is usually fatal. 5Aside from death, acute cyanide toxicity at small doses can cause headache, tightness in throat and chest, and muscle weakness. The effects of chronic (long-term) exposure to cyanide are less well known.
Plant | mg/100 g HCN | Glucoside |
---|---|---|
Bitter almonds | 250 | Amygdalin |
Cassava root | 53 | Linamarin |
Whole sorghum | 250 | Dhurrin |
Lima bean | 10-312 | Linamarin |
References
Back to List of Endogenous Plant Toxins
Prepared Summer 1997 by Bernadene Magnuson, Ph.D.
University of Idaho, Dept. of Food Science and Toxicology - EXTOXNET FAQ Team.