PULLMAN — Washington State University professor John Fellman is a member of an international team recently funded by an $8.3 million grant from the Gates Foundation to improve the nutrition and shelf life of a staple that feeds more than 500 million people around the globe: cassava.
Specifically, Fellman, a post-harvest plant physiologist in the College of Agricultural, Human, and Natural Resource Sciences, will study why the dark brown, sweet-potato-like root begins to lose its nutritional values within 72 hours of being harvested.
“We’ll be looking at an oxidizer that renders what little protein exists in the root indigestible almost immediately,” Fellman said. “What sort of signals does the root receive to self destruct?”
Cassava ranks fourth in the world, behind rice, sugar and corn, as a staple food. Originating from South America, it is grown throughout the tropical world and can be grown in poor soils and drought conditions. While a good source of carbohydrates, cassava is low in protein and deficient in micronutrients such as iron, zinc and vitamin A.
In addition, the plant generates naturally occurring cyanogens, which liberate cyanide into the root. Shredding the roots and squeezing the juice out removes much of the toxins, and the heat used to dry the resulting flour removes most of the remaining compounds. However, cassava not properly prepared can be deadly.
As part of its Grand Challenges in Global Health program, the Gates Foundation supported the project called BioCassava Plus. The primary objective of the project is to “improve the health of Africans through development and delivery of novel cassava…having increased … levels of zinc, iron, protein and vitamins A and E,” according to the team’s grant proposal. The team includes 19 scientists from the U.S. Department of Agriculture, and universities and government agencies around the globe.
The team also will examine post-harvest durability and ways to reduce the cyanogens. Fellman said he will spend his portion of the grant to hire a postdoctoral researcher and look at the chemical signals that spur and speed deterioration of the cassava root once it is harvested.
If successful, the team has the potential to change how farming operates in Third World countries and could turn cassava into a commodity crop as well as a local food source, Fellman said.
