Possible causes and the molecular basis of hydrogen cyanogenesis production in cassava

Abstract

Cassava (Manihot esculenta), is a major source of carbohydrates after rice and maize providing a basic diet to over half a billion people. It is an annual crop belonging to the family Euphorbiaceae. It produces edible root tubers which form the staple food for inhabitants in the developing world mainly in the tropical and subtropical countries. It is a very drought tolerant crop which is classified as either bitter or sweet cassava. However, it produces Hydrogen Cyanide (HCN) which is toxic. This ant nutritional component can cause partial paralysis and have been known to kill and wipe out families in Africa. It is surprising that farmers seem to prefer the bitter varieties as they are starchier, deter pests and wild animals. There have not been adequate studies to evaluate the causes and molecular basis of the production of Hydrogen cyanide by cassava. Observations of feeding patterns of porcupines on cassava roots, defense mechanisms in cassava and macro level results on cassava metabolism were hereby used to explain the molecular epigenetic link of cyanogenesis of cassava. The results explain the exogenous release and its subsequent removal of HCN during cassava processing. It shall form the basis for the selection and improvement of cassava products for food security.