Assessment of Iron Bioavailability and Iron Biofortification of Staple Food Crops: Guiding the Breeding Approach with in vitro and in vivo Screening Tools
Raymond Glahn *
USDA, Ithaca, NY, USA and Cornell University, Ithaca, NY, USA.
Elad Tako
USDA, Ithaca, NY, USA and Cornell University, Ithaca, NY, USA.
*Author to whom correspondence should be addressed.
Abstract
Objectives: The objective of this presentation will be to demonstrate how the combination of in vitro screening and an animal model can be extremely useful to develop and monitor Fe-biofortified crops, and evaluate meal plans in advance of human studies to determine if the crop is adequately biofortified with Fe prior to expensive human testing.
Methods: In recent years much has been learned about how to properly screen varieties of staple food crops to improve the Fe content and bioavailability. Research has shown that simply measuring Fe content and levels of known inhibitors such as phytic acid and total polyphenols is not adequate to guide crop breeding efforts, as it leads to misdirection because of inability to assess all of the genetic, environmental, and environment by genotype interactions that play a role in Fe bioavailability from staple foods. Moreover, once Fe-biofortified crops are developed and released, there needs to be cost effective methodology in place to monitor and maintain the nutritional quality of successive harvests.
Results: This presentation reports on a decade of applications of a high throughput bioassay (in vitro digestion/Caco-2 model) and a poultry feeding model that have been developed and applied to a variety of staple food crops (eg. beans, lentils, maize, sorghum and pearl millet). Recent comparisons to human efficacy trials involving black beans, pearl millet and red mottled beans from Rwanda will be presented and discussed.
Conclusions: Overall, these results show a positive correlation with human studies and support this approach for future Fe-biofortification efforts.