Iron bioavailability of low and high phytic aid maize produced via recurrent selection (1042.4)

Abstract

Phytic acid is a potent inhibitor of iron absorption and is abundant in staple food crops. Low phytic acid (lpa) maize mutants have been produced, but have poor germination rates. The first objective of this study was to determine if conventional breeding can be used to select for phytic acid content in maize without reductions in germination rate, and the second objective was to determine the iron bioavailability of maize produced through this method. For the first objective, the BS11 maize population was used in a recurrent selection breeding program to selectively breed for both low phytic acid (BS11LPA) and high phytic acid (BS11HPA) content, and germination tests were performed for both groups and compared with the lpa mutant. For the second objective, maize samples were subjected to in vitro digestion and then applied to Caco‐2 cells to assess iron bioavailability. Our results show that phytic acid content is significantly different among all three maize varieties, with BS11HPA>BS11LPA>lpa mutant (p<0.05). Germination rates for both BS11LPA and BS11HPA are significantly (p<0.05) greater than for the lpa mutant. Iron bioavailability was ≍35% higher in the BS11LPA maize than the BS11HPA maize (p<0.05, n=8), but there was no significant difference in bioavailability between BS11LPA and lpa mutant maize (p>0.05, n=8). This study concludes that selective breeding can produce low phytic acid maize with better germination rates than lpa mutant maize, and that this maize has similar iron bioavailability compared with lpa mutants.Grant Funding Source: Supported by USDA‐ARS