Cyanogenic glycosides types

FIGURE 17. Types of cyanogenic glycosides Glc = glucose residue Gen, Pri and Vic = gentiobiose, primaverose (disaccharide) and vicianose residues, respectively... 

Since 1970, a new class of cyano compounds has been isolated from certain seed oils that are of interest as some members, like cyanogenic glycosides, liberate HCN on enzymic or mild chemical hydrolysis All the authenticated compounds occur in several genera of the Sapindaceae (soapberry) family " and they can comprise up to 50% v/v of the extract, e.g. in kusum seed oil. These cyanolipids are mono- or di-esters of mono- or dihydroxy-nitriles and 4 types are known (Figure 22). The chain length of the fatty acid moiety, which may be saturated or not (e.g. commonly from oleic acid), can be C14 to C22 with C18 and C20 predominant and the double bond in type 3 can be Z or E, but structural variations are few. After hydrolysis the a-hydroxynitriles derived from types 1 and 4 are cyanogenic. In many plant species one type occurs to the virtual exclusion of the others thus type 1 accumulates in Allophyllus and Paullina spp, whereas type 2 is characteristic of... 

Major Structural Types of Cyanogens Cyanogens Derived from Phenylalanine Cyanogens Derived from Tyrosine Cyanogens Derived from Valine and Isoleucine Cyanogens Glycosides Derived from Leucine Cyanolipids... 

In some instances, when an unnatural enzyme is added to a substrate and the natural enzyme then added, no reaction is observed. The nature of these effects is dependent on concentrations of enzymes and substrates as well as the order of addition. Interactions of this type for cyclopentenoid cyanogenic glycosides and the corresponding enzyme system have been reviewed (Spencer, 1987). 

Seigler, D. S., Cyanogenic glycosides and lipids Structural types and distribution, in Cyanide in Biology (B. Vennesland, E. E. Conn, C. J. Knowles, J. Westley, and F. Wissing, eds.), 1133-143, Academic Press, London, 1981b. 

Many plants accumulate compounds capable of liberating hydrogen cyanide upon acid or enzymatic hydrolysis. Two types of compounds, cyanogenic glycosides and... 

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