Glycosides from which cyanide is formed by the activity of hydrolytic enzymes. More than 1000 plant species from 90 families and 250 genera have been reported to be cyanophoric. The cyanogenic glycoside molecule consists of a monosaccharide (glucose) or disaccharide (vicianose or gentiobiose) and an aglycone in the form of a β-hydroxynitrile. The glycoside is hydrolyzed in the presence of p-glucosidase; the nitrile undergoes further degradation by a lyase, generating hydrogen cyanide and other metabolites.