Fabrication of a donkey spleen ferritin–pectin complex to reduce iron release and enhance the iron supplementation efficacy

Iron deficiency is a global issue, influencing more than one-third of the population in the world. Ferritin as a natural iron-containing protein is considered a marvelous iron supplement due to its biocompatibility, biodegradability and bioavailability. However, foodstuffs contain plenty of reductants which could induce iron release from the cavity of ferritin and cause oxidative damage. In this study, we aimed to prevent the iron release from donkey spleen ferritin (DSF) by pectin encapsulation driven by the electrostatic interaction and evaluated the iron supplementation of the DSF-pectin complex (DPC). After DSF was purified, we fabricated the DPC and the iron release was decreased by 53.68% after 60 min when DSF : pectin was 1 : 10 (w/w). TEM analysis showed that ferritin in the DPC is clustered in a linear pattern, and the cell viability assay indicated that the DPC has no toxicity towards Caco-2 cells. In the mouse experiment, the DPC increased the content of serum iron and serum ferritin with no significant difference from the control check. Furthermore, the DPC increased the iron content in the liver, suppressed the expression of hepcidin and increased the expression of ferroportin. These results suggested that the DPC could prevent the interactions between food components and ferritin and is a promising iron supplement to ameliorate iron deficiency.