Cyanogenic glycoside, occurrence

Figure 7.11 (Continued) (e) Occurrence of cyanogenic glycosides. Key to branches leading to families that accumulate cyanogens. See also legend (a).

Cyanogenic glycosides appear to be more common in the ancestral legume tribes (Fig. 7.11e). Whether the occurrence of cyanogenic glycosides is based on common genes that are turned off in most instances and turned on in a few cannot yet be answered both convergent and independent evolution are plausible scenarios. 

Cyanogenic glycoside molecular formula Mr mp. ["Cl optical activity occurrence CAS... 

Whether the occurrence of an enzyme in a particulate fraction really represents its in vivo location can be substantiated by the following properties (a) close binding to membrane lipids, cf. cyclopenase (D 8.4.2), which is a lipoprotein of the plasma membrane (b) cooperation with other enzymes, cf. the catalytic facilitation in the biosynthesis of cyanogenic glycosides, cinnamic and benzoic acids (A 3.1) and (c) in situ examination by cytochemical methods, cf. the localization of phenol oxidases (C 2.3.1), peroxidases (C 2.4) and thioglucosidases (D 9.4). 

In contrast to the Solanaceae, which seem to have lost the ability to synthesize cyanogenic glycosides, there are a number of reports on the occurrence of these compounds in the Convolvulaceae. These reports often documented only presence of... 

The occurrence of these cyanogenic glycosides, which possess aglycones with a cyclopentenyl structure, appears to be restricted to the Passifloraceae, Turneraceae, Flacourtiaceae, and Malesherbiaceae (45, 121, 122, 123, 126, 129, 130, 132, 143). These cyclopentenyl-glycosides may be chemotaxonomic markers in these plants. 

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