Plant cyanogenic glycosides.

Area of Science:

• Plant biochemistry and natural products chemistry.
• Plant physiology and ecology.
• Toxicology and animal health.

Background:

• Cyanogenic glycosides (CGs) are secondary metabolites found in over 2500 plant taxa, notably in families like Fabaceae and Rosaceae.
• These compounds consist of an aglycone and a sugar moiety, with their production influenced by genetic and environmental factors.
• The biosynthesis of CGs involves amino acid precursors, leading to alpha-hydroxynitriles, while their degradation releases hydrogen cyanide (HCN).

Purpose of the Study:

• To provide a comprehensive review of cyanogenic glycosides (CGs) in plants.
• To discuss the biosynthesis, degradation pathways, and genetic control of cyanogenesis.
• To explore the ecological roles, plant defense mechanisms, and toxicological effects of CGs.

Main Methods:

• Review of existing literature on cyanogenic glycosides.
• Discussion of analytical methods for CG determination (photometrical and chromatographic).
• Analysis of biosynthetic pathways and enzymatic degradation processes.

Main Results:

• Cyanogenesis involves complex biosynthetic pathways from L-amino acids and enzymatic degradation.
• Plant tissues compartmentalize CGs and hydrolyzing enzymes to prevent self-toxicity.
• CGs play roles in plant defense, but can cause significant poisoning in livestock and humans, as exemplified by cassava.

Conclusions:

• Cyanogenic glycosides are widespread plant compounds with diverse biological roles.
• Understanding CGs is crucial for agriculture, animal husbandry, and human health due to their toxicity.
• Further research into CGs can lead to improved crop management and mitigation of poisoning risks.