Iron Biofortified Carioca Bean (Phaseolus vulgaris L.)—Based Brazilian Diet Delivers More Absorbable Iron and Affects the Gut Microbiota In Vivo (Gallus gallus)

Abstract

Biofortification aims to improve the micronutrient concentration and bioavailability in staple food crops. Unlike other strategies utilized to alleviate Fe deficiency, studies of the gut microbiota in the context of Fe biofortification are scarce. In this study, we performed a 6-week feeding trial in Gallus gallus (n = 15), aimed to investigate the Fe status and the alterations in the gut microbiome following the administration of Fe-biofortified carioca bean based diet (BC) versus a Fe-standard carioca bean based diet (SC). The tested diets were designed based on the Brazilian food consumption survey. Two primary outcomes were observed: (1) a significant increase in total body Hb-Fe values in the group receiving the Fe-biofortified carioca bean based diet; and (2) changes in the gut microbiome composition and function were observed, specifically, significant changes in phylogenetic diversity between treatment groups, as there was increased abundance of bacteria linked to phenolic catabolism, and increased abundance of beneficial SCFA-producing bacteria in the BC group. The BC group also presented a higher intestinal villi height compared to the SC group. Our results demonstrate that the Fe-biofortified carioca bean variety was able to moderately improve Fe status and to positively affect the intestinal functionality and bacterial populations.

Nicotianamine-chelated iron positively affects iron status, intestinal morphology and microbial populations in vivo (Gallus gallus)

“…serum, and all animal tissues was determined by nitric/perchloric acid digestion as previously described 38 followed by inductively coupled plasma-optical emission spectrometry (ICP-OES) using a Thermo iCAP 6500 series (Thermo Jarrell Ash Corp., Franklin, MA, USA). Fe-NA solution (Fe-NA); (6) 'Control' white flour extract (C WF); (7) 'Biofortified' white flour extract (B WF) and eggs were subsequently incubated for four days until hatch as described in 79,80 .…”

“…Chicks were euthanized by CO 2 exposure after hatching and all tissues were collected. The remaining hatchlings (n = 30) were allocated based on body weight into two treatment groups: (1) 80% 'Control' white flour diet ('Control') and (2) 80% 'Biofortified' white flour diet ('Biofortified') as described in 38 . All chickens received a commercial diet (Nutrena ® Chick Starter Grower 18% Crumble, Cargill Inc, Wayzata, MN, USA) for one week prior to consumption of 'Control' and 'Biofortified' diets for six weeks.…”

“…Blood plasma Hb concentrations were determined spectrophotometrically using the Triton ® /NaOH method according to manufacturer's instructions (Hemoglobin Assay Kit, Sigma, St. Louis, MO, USA). The Hb maintenance efficiency (HME) was calculated as previously described 38 . Blood serum Linoleic Acid:Dihomo-γ-Linolenic Acid ratio (LA:DGLA) was determined as previously described 39 .…”

“…Total RNA extraction from duodenal and heart tissue (30 mg) using Qiagen RNeasy Mini Kit (RNeasy Mini Kit, Qiagen Inc., Valencia, CA, USA), cDNA synthesis and real time-polymerase chain reaction (RT-PCR) analysis were performed as previously described 38,81 with minor adjustments. In brief, the cycle product (Cp) of each gene (2020) 10:2297 | https://doi.org/10.1038/s41598-020-57598-3 www.nature.com/scientificreports www.nature.com/scientificreports/ was quantified using a seven-point standard curve in duplicate.…”

“…The chicken (Gallus gallus) model is physiologically relevant for estimating dietary micronutrient absorption in humans due to similarities in intestinal morphology and enteric microbiota, and has been used in numerous studies to evaluate Fe and Zn bioavailability in staple foods [35][36][37][38][39][40][41][42][43][44] . Here we utilized the chicken model to investigate the impact of NA-chelated and EDTA-chelated Fe on Fe status and gastrointestinal health when delivered alongside extracts of control and biofortified white wheat flour containing increased NA, Fe, Zn and DMA through intraamniotic administration four days prior to hatch (short-term exposure).…”