Practical ecological knowledge for the temperate reader.

Cyanogenic Compounds

Cyanogenic Glycosides

  • Sambucus - Elderberry [PTH]
  • Cycas Sp. - Cycads [Barceloux MTNS]
  • Casava root - Manihot esculenta [CRNAH][Ashraf PAP][Barceloux MTNS]
  • Trifolium pratense flower heads - Red Clover [Capasso PQR]
  • Lotaustralin (in Lotus corniculatus - Bird's food trefoil) [Barceloux MTNS]
  • Amygdalin ( Rosaceae - in Prunus Spp and Malus domestic. - Fruit Kernels) "...contain up to 6% amygdalin on a fresh weight basis, whereas the cyanogenic glucoside content of the pulp ranges from about 0.001 – 0.01%." [Barceloux MTNS]
  • Gynocardin - Gynocardia Spp. and Pangium Spp. [Barceloux MTNS]
  • Vicianin (Fabaceae, Polypodiaceae) - Vica Spp.[Barceloux MTNS]
  • Sambunigrin (Caprifoliaceae, Mimosaceae, Oleaceae) [Barceloux MTNS]
  • Lucumin - Lucuma Spp. [Barceloux MTNS]
  • Taxiphyllin - Taxus Spp. [Barceloux MTNS]
  • Zierin - Zieria Spp. [Barceloux MTNS]
  • Proteacin - Macadamia spp. [Barceloux MTNS]
  • Linamarin, linustatin, neolinustatin - Flax - Linum usitatissimum[Mills HMPL][Barceloux MTNS] Trifolium repens - White Clover [Barceloux MTNS]
  • Prunasin [Barceloux MTNS]
  • Dhurrin (in Sorghum spp.) [Barceloux MTNS]
  • P -Glucosyloxymandelonitrile - Nandina spp. [Barceloux MTNS]
  • Triglochinin - Alocasia macrorrhiza [Wink BBPSM] Triglochin Spp. [Barceloux MTNS]
  • Deidaclin - Deidamia Spp. [Barceloux MTNS]
  • Tetraphyllin A & B- Tetrapathaea Spp. [Barceloux MTNS]

Natural Sources

"In plants, cyanides are generally found in bound forms as cyanogenic glycosides and play an important role in plant defense against herbivory." "Overall, cyanogenic glycosides have been reported to occur in more than 3000 plant species (ca. from 130 families) and thus these species have a potential to produce HCN toxicity if ingested by animals and humans." [Ashraf PAP]

"The separation of cyanogenic glycosides and the degrading enzymes in the plant tissues prevents the formation of significant amounts of cyanide until the physical disruption of the plant compartments." [Barceloux MTNS]

"During the 1980s, U.S. interest in botanicals resurfaced under the guise of ‘‘complementary and alternative medicine’’ (CAM). By this time, botanicals had lost considerable credibility. Proponents of ‘‘Laetrile’’- a concoction of cyanogenic glycosides extracted from peach pits—drew media attention when the FDA began seizing the product as an ‘‘unapproved’’ drug and as ‘‘ineffective cancer treatment’’ (13). However, by 1991, in response to growing consumer interest, the U.S. Congress appropriated funds to the National Institutes of Health for the establishment of a federal research program for the scientific evaluation of CAM." [LAM HSDI]

"Laetrile (amygdalin) was a very popular cancer remedy in the 1980s despite clinical evidence of a lack of effect. Unfortunately, after pure amygdalin was banned, patients tried ingesting large amounts of apricot kernels, which led to several deaths because apricot kernels also contain an enzyme that hydrolyzes amygdalin and releases cyanide. Subsequent research showed that amygdalin alone can lead to cyanide poisoning." [Mills HMPL]

"In populations where cassava is a staple crop, care is taken to soak, grate, and ferment the cassava, allowing the release of HCN before consumption. Lima beans can be a problem if cooked at low temperature, which is insufficient to destroy toxic glycosides. As few as 12 bitter almonds can potentially kill a small child." [Omaye FNT]

"The genus Ximenia belongs to the Olacaceae and comprises about 8 species (Brasileiro et al., 2008): .... X. americana Linn. is the most common, being native to Australia and Asia where is commonly known as Yellow Plum or Sea Lemon. It is found mainly in tropical regions (Africa, India, New Zealand, Central America and south America), specially Africa and Brazil. In Asia, the young leaves are consumed as a vegetable, however, the leaves also contain cyanide and need to be thoroughly cooked, and should not be eaten in large amounts." [Rao Phyt]



"Bamboo shoots are the newly emerged, edible shoots of several species of bamboo, in genera of the subfamily Bambusoideae, including Phyllostachys, Bambusa, and Dendrocalamus.... After removing the leaf sheaths, the stems are boiled for about half an hour to remove any bitterness (cyanogenic glycosides) but to retain their crisp texture. They are a particularly common food item in China, Japan, Korea, and Southeast Asia, and in many other countries..." [Prance CHP]





(Cyanogenic Glycoside)

  • leaves and seeds of cherry, almond, and peach [Ashraf PAP] Kernels of all 3 sp. [MNP Dewick]
  • Apricot and plum kernels [MNP Dewick]
  • Prunus Sp. "Cyanogenic glycosides, amygdalin, 0.2 to 8.5% (corresponding to 12 to 500 mg prussic acid per 100 gm)" [PDR]
  • Activities

Properties: "Amygdalin itself is not especially toxic to animals; toxicity depends on the co-ingestion of the hydrolytic enzymes. Although formed by the hydrolysis of amygdalin, prunasin is also a natural cyanogenic glycoside and may be found in seeds of black cherry (Prunus serotina) and in the seeds and leaves of cherry laurel (Prunus laurocerasus)." [MNP Dewick]

"10 bitter almonds are said to be fatal for a child, 60 for an adult (a fatal dosage would presumably be already reached at a lower level, given disadvantageous conditions - higher cyanide level in the almonds, intensive chewing). Recommended antidotes include injection of solutions of dicobalt EDTA or thiosulfates or else application of methemoglobinforming substances, such as amyl nitrite." [PDR]

"...a total consumption of about 48 apricot kernels produced forceful vomiting, headache, flushing, heavy sweating, dizziness, and faintness before vomiting was induced in the emergency room, whereafter the symptoms rapidly subsided. In another case accidental poisoning was fatal (6)." [SEHM]






(Cyanogenic Glycoside)

  • Aruncus dioicus - Goatsbeard (aerial parts)[Hung Vo et al.]
  • Prunus Sp. - Wild cherry bark [Mills HMPL]
  • Activities
  • Properties:



[Wink BBPSM]



(Cyanogenic Glycoside)

  • Alocasia macrorrhizos [Wink BBPSM] (Araceae)(L.) G. Don - Giant taro: Young leaves [EMNMPV.9]
  • Triglochin Spp. [Barceloux MTNS]
  • Triglochin maritima [Wink BBPSM]
"The cyanogenic glucoside, triglochinin, reveals a quite unusual structure .... Indeed, triglochinin does not represent an aromatic compound, but appears to be derived from tyrosine (Nahrstedt et al., 1984). Biosyn- thetic details, especially the reactions involved in ringopening, are unknown. Isotriglochinin, a Z-isomer of triglochinin, and triglochinin-methylester have been reported, but both appear to be produced as artefacts during isolation (Conn, 1981)." [Wink BBPSM]

"In plants like Alocasia or Triglochin, the Beta-glucosidases are strictly specific for the cyanogenic glucoside, triglochinin, that occurs in these plants" [Wink BBPSM]

  • Activities
  • Properties:



"The leaves of various plants are also fermented to produce food products in parts of Africa. Ntoba mbodi is produced in Congo and central Africa from cassava (Manihot esculenta Crantz) leaves. This food is relatively rich in protein, despite a slight reduction in free nitrogen during fermentation, most likely due to liberation of hydrogen cyanide." [Sarkar HIFIAF]

"During the fermentation process, amines are produced by Bacillus spp., especially B. pumilus, which have the capacity to utilize cyanhydric acid for nutrition (Knowles, 1976). This invariably reduces the cyanide content of the fermenting cassava leaves during the fermentation. The decrease in the nitrogen content from 5.1% to 4.5% obtained during the fermentation was suggested to be due to the solubilization and volatilization of hydrogen cyanide (Kobawila et al., 2005)...". [Sarkar HIFIAF]

"The detoxification of cassava through fermentation includes an acid fermentation, during which the cyanogenic glycosides are hydrolyzed to liberate the toxic cyanide gas (Onabolu et al. 2002a,b). For example, cassava roots contain two cyanogenic glucosides, linamarin and lotaustralin (Ray and Ward 2006). When the roots are naturally fermented by a mixed population of yeasts (Saccharomyces cereviseae and Candida spp.) and LAB (Lactobacillus, Leuconostoc and Pediococcus), the cyanogen level is reduced drastically (Kostinek et al. 2005)." [Ray MFTF]

"...some classes of inorganic compounds such as cyanides and azides are toxic to many microbes [22]; however, these compounds may be degraded following a period of microbial adaption [112]. In this respect, certain studies have indeed shown the fungal biodégradation of cyanide and microbial adaption to such toxic compounds." [Mohee BS]


Cyanide Exposure, Toxicity and Treatment


"The clinical features associated with the ingestion of cyanogenic glycosides mimics cyanide poisoning, and the severity of the intoxication correlates to the dose of active cyanogenic compounds. The onset of vomiting, abdominal pain, weakness, dyspnea, diaphoresis, and lightheadedness followed by convulsions, stupor, disorientation, hypotension, metabolic acidosis, coma, respiratory failure, and cardiovascular collapse develops after exposure to high doses of cyanogenic glycoside - containing foods.... Symptoms typically start within one half hour after consumption and progress quickly. A case series associated the ingestion of wild apricot seed ingestions by Turkish children with the sudden onset of vomiting and crying followed by fainting, lethargy, and coma." [Barceloux MTNS]

An interaction of amygdalin with vitamin C has been suggested: "Vitamin C increases the in vitro conversion of amygdalin to cyanide and reduces body stores of cysteine, which detoxifies cyanide; the authors suggested that this was a plausible explanation for this adverse event." [SEHM]

Effect on Animals:


"Local communities usually only have very small quantities of cyanide antidotes on hand due to their expense, short expiration dating, and rarity of use. However, some cities are stockpiling kits. The exhaled breath of cyanide exposure victims may smell like bitter almonds. Not everyone (only 40–60% of people) can detect this odor" [Koehler PC]

"Treatment of poisoning from exposure to cyanogenic plants is similar to the treatment of cyanide poisoning. Decontamination measures are not usually necessary because of the limited absorptive capacity of activated charcoal to cyanide. Mild to moderate ingestions usually require only supportive care. Indications for the use of an antidote... include alteration in mental status, severe acidosis, continuous seizures, and refractory hypotension. The administration of the cyanide antidote kit to children requires the appropriate adjustments for weight and hemoglobin content to avoid methemoglobinemia. Clinical features that suggest an appropriate response to nitrites and thiosulfate or hydroxocobalamin include the following: normalization of vital signs (blood pressure, pulse), normal mentation, cessation of seizure activity, spontaneous respirations, and resolution of metabolic acidosis.... The presence of persistent metabolic acidosis may require a continuous infusion of sodium thiosulfate (2 g/h) for 24 hours.... Survival has occurred in patients with cyanide poisoning including laetrile - induced, severe cyanide intoxication (coma, metabolic acidosis, profound hypotension requiring aggressive support with vasopressors) following only supportive care..." [Barceloux MTNS]

Some Treatment Options Include;

Journals of Interest


Page last modified on Monday, December 27, 2021 10:55 AM