POSSIBLE USE OF A BIOTECHNOLOGICAL APPROACH TO OPTIMIZE AND REGULATE THE CONTENT AND DISTRIBUTION OF CYANOGENIC GLUCOSIDES IN CASSAVA TO INCREASE FOOD SAFETY.

B. Koch, O. Sibbesen, E. Swain, R. Kahn, D. Liangcheng, S. Bak, B. Halkier, B. Møller
This paper summarizes some of our work on elucidating the biosynthetic pathway for cyanogenic glucosides and on the identification of the structural genes involved. Cyanogenic glucosides are present in more than 2500 different plants some of which like cassava are important crop plants. Upon damage of plant tissues containing cyanogenic glucosides, these will be partly or fully hydrolyzed into cyanohydrins and cyanide. Plant materials containing high amounts of cyanogenic glucosides like cassava thus need careful processing before being used as food. When careful processing is not carried out, cassava consumers may be exposed to high levels of cyanide.

One goal of our research program is to be able to understand why some plants produce cyanogenic glucosides and to find out whether it will be possible to down-regulate the production of these compounds in crop plants to increase food safety. If complete elimination of the cyanogenic glucosides results in plants sensitive to pests or with other undesired characteristics, then the cyanogenic glucosides should be eliminated or specifically reduced only in those parts of the plants used for human consumption. The techniques of molecular biology will enable us to obtain such plants but probably not within the next decade.

The possible role of cyanogenic glucosides in plants is very difficult to assess at present since many argued functions are not properly documented in the literature. The most solid documented effect of cyanogenic glucosides is that their presence actually increases the sensitivity of at least some plants to fungal attack apparently by lowering the plants ability to produce defense compounds like phytoalexins.

In this paper several opinions we often have heard presented at meetings on cassava, cyanogenic glucosides and toxicity are discussed although these opinions in many cases are not scientifically documented. Thus no citations to literature can be given. It is important that more research is carried out on cassava so that solid answers can be provided to some of these fundamental questions raised.

Koch, B., Sibbesen, O., Swain, E., Kahn, R., Liangcheng, D., Bak, S., Halkier, B. and Møller, B. (1994). POSSIBLE USE OF A BIOTECHNOLOGICAL APPROACH TO OPTIMIZE AND REGULATE THE CONTENT AND DISTRIBUTION OF CYANOGENIC GLUCOSIDES IN CASSAVA TO INCREASE FOOD SAFETY.. Acta Hortic. 375, 45-60
DOI: 10.17660/ActaHortic.1994.375.2
https://doi.org/10.17660/ActaHortic.1994.375.2
Cyanogenesis, biosynthetic pathway, cytochrome P450, cassava processing

Acta Horticulturae