Iron Concentrations in Biofortified Beans and Nonbiofortified Marketplace Varieties in East Africa Are Similar

Abstract

Background The predominant bean iron (Fe) biofortification approach is to breed for high Fe concentration and assumes the average Fe concentration is 50 μg/g. This approach also assumes that a 40 μg/g increase is sustainable and Fe bioavailability will not decrease to negate the increase in Fe. Objective The overall objective was to determine if bean Fe biofortification via breeding for high Fe is producing beans with higher Fe concentration relative to nonbiofortified lines found in the East Africa marketplace. Methods Seventy-six marketplace samples (East Africa Marketplace Collection; EAMC), and 154 genotypes known to be representative of the marketplace were collected from breeders in the Pan-Africa Bean Research Alliance (designated the East Africa Breeder Collection; EABC). Within the EAMC and EABC were 18 and 35 samples, respectively, that were released as biofortified lines. All samples were measured for Fe concentration. The Caco-2 cell bioassay assessed Fe bioavailability of the EAMC. Biofortified versus nonbiofortified samples were compared by the appropriate t-test or ANOVA. Results The Fe concentration of the 58 nonbiofortified EAMC lines was (mean ± SD [range]) 71 ± 9 μg/g (52–93 μg/g) which did not differ significantly from the 18 biofortified EAMC varieties (71 ± 11 μg/g [55–94 μg/g]). The Fe concentration of the 119 nonbiofortified EABC varieties was 66 ± 7 μg/g (51–90 μg/g) which was significantly different (P < 0.0001) from the 35 EABC biofortified lines (73 ± 9 μg/g [60–91 μg/g]). However, the EABC biofortified lines were not different from the nonbiofortified EAMC samples. In the Caco-2 cell bioassay, biofortified EAMC varieties did not deliver more Fe compared with nonbiofortified EAMC varieties. Conclusions The assumptions of the high Fe bean biofortification approach are not met in the East African marketplace. Iron concentration and bioavailability measurement indicate the biofortified bean varieties are providing no additional dietary Fe.

Investigation of Genotype by Environment Interactions for Seed Zinc and Iron Concentration and Iron Bioavailability in Common Bean

“…Seed FeBIO was not correlated to either seed Fe and Zn concentration as has been previously reported by Katuuramu et al (2018) . Additionally, upon screening of marketplace and breeder collections of common bean from Eastern Africa, it was reported that the Fe concentrations between biofortified and non-biofortified genotypes were similar ( Glahn et al, 2020 ). This suggests that seed Fe concentration is independent of seed FeBIO.…”

Genetic control of iron bioavailability is independent from iron concentration in a diverse winter wheat mapping population

“…Given the chemical nature of Fe and its interaction with phytochemicals such as phytate, phenolic acids and polyphenols, recent studies now show that it is essential to also evaluate the delivery of Fe (i.e. Fe bioavailability) simultaneously with Fe concentration [ 45 , 46 ].…”

Genetic Control of Iron Bioavailability is Independent from Iron Concentration in a Diverse Winter Wheat Mapping Population

“…Given the chemical nature of Fe and it's interaction with phytochemicals such as phytate, phenolic acids and polyphenols, recent studies now show that it is essential to also evaluate the delivery of Fe (ie. Fe bioavailability) simultaneously with Fe concentration [44,45]. Thus, our goal was to understand how higher grain Fe concentration in wheat could play a role in increased iron absorption/bioavailability.…”