The Dose makes the Poison. A principal concept of Toxicology, first expressed by Paracelcus, an early 16th century physician and alchemist. Did you know that many of your favorite foods naturally contain incredibly potent toxins that can, and have been known, to kill? Not to put you off your potatoes, but here are some infamous poisons found in edible plants.
• Solanine: Never eat potatoes that have turned green because that indicates the presence of solanine, a toxic glycoalkaloid. Although the green color is caused by harmless chlorophyll, solanine is also produced in response to light and is highest just under the skin and in the “eyes” or sprouts. Symptoms range from nausea to death. Although one would need to pig out on green potatoes to die from it, people have been poisoned drinking potato leaf tea. In fact, the Solanaceae family that has also given us our beloved tomatoes, eggplants and tobacco, is chock full of deadly poisons. They include nicotine, atropine and scopolamine. Let’s just say that the genus Atropa (deadly nightshade) is named after the Greek Fate, Atropos, who cut the thread of life.
• Cyanide: More than 500 million people rely on cassava as a source of food, the third most consumed source of starch in the world. Yet, it contains a cyanogen named linamarin, that converts to cyanic acid when eaten. If not processed properly, cassava causes neurological disease and death. On a positive note, the combination of the enzyme linamarase with linamarin could be used to treat cancer in a strategy dubbed suicide gene therapy. Most of the cyanide is produced outside the cells, resulting in a “bystander effect” that kills off the tumor.
• Myrisitin: A psychoactive drug chemically similar to mescaline and amphetamine found in nutmeg and mace. It binds to the brain’s serotonin receptors and causes hallucinations, along with other less pleasant effects. Getting high on nutmeg is teen fad that can be dangerous.
• Phytohaemagglutinin: Causes red blood cells to clump. Found in highest concentrations in raw red kidney beans (also white/cannellini beans), a single bean can have 70,000 haemagglutinating units. As few as five raw beans can bring on nausea, vomiting and worse within a few hours of consumption. This can be reduced by boiling for at least 10 min. However, slow cooking actually increases the toxin levels up to five times! On the bright side, these compounds are useful in research for tracing the connections between neurons, and in medicine, for activating cell division in T-lymphocytes.
Images: Idaho native Gnotic Pasta posed for these pictures with the world famous spuds and inspired this post. Many thanks, Dan!
A G+ Collaboration for ScienceSunday !