Iron delivery systems for controlled release of iron and enhancement of iron absorption and bioavailability

Preparation and characterization of metal-polyphenol networks encapsulated in sodium alginate microbead hydrogels for catechin and vitamin C delivery

A novel encapsulation system was designed, utilizing sodium alginate (SA) polysaccharide as the matrix and easily absorbed Fe2+ as the metal-organic framework, to construct microbead scaffolds with both high catechins (CA) and vitamin C (Vc) loading and antioxidant properties. The structure of microbead hydrocolloids was investigated using SEM, XPS, FTIR, XRD and thermogravimetry, and the antioxidant activity, in vitro digestion and the release of CA and Vc were evaluated. These results revealed that the microbead hydrocolloids SA-CA-Fe and SA-CA-Vc-Fe exhibited denser and stronger cross-linking structures, and the formation of inter- and intramolecular hydrogen and coordination bonds improved thermal stability. Moreover, SA-CA-Fe (44.9 % DPPH and 47.8 % ABTS) and SA-CA-Vc-Fe (89.9 % DPPH and 89.3 % ABTS) displayed strong antioxidant activity. Importantly, they were non-toxic in Caco2 cells. The SA-CA-Fe and SA-CA-Vc-Fe achieved significantly higher CA (56.9 and 62.7 %, respectively) and Vc (42.2 %) encapsulation efficiency while maintaining higher CA and Vc release in small intestinal environment. These results suggested that SA polysaccharide-based encapsulation system using Fe2+ framework as scaffold had greater potential for delivery and controlled release of CA and Vc than conventional hydrocolloids, which could provide new insights into the construction of high loading, safe, targeted polyphenol delivery system.

Mineral-element-chelating activity of food-derived peptides: influencing factors and enhancement strategies

Mineral elements including calcium, iron, and zinc play crucial roles in human health. Their deficiency causes public health risk globally. Commercial mineral supplements have limitations; therefore, alternatives with better solubility, bioavailability, and safety are needed. Chelates of food-derived peptides and mineral elements exhibit advantages in terms of stability, absorption rate, and safety. However, low binding efficiency limits their application. Extensive studies have focused on understanding and enhancing the chelating activity of food-derived peptides with mineral elements. This includes obtaining peptides with high chelating activity, elucidating interaction mechanisms, optimizing chelation conditions, and developing techniques to enhance the chelating activity. This review provides a comprehensive theoretical basis for the development and utilization of food-derived peptide-mineral element chelates in the food industry. Efforts to address the challenge of low binding rates between peptides and mineral elements have yielded promising results. Optimization of peptide sources, enzymatic hydrolysis processes, and purification schemes have helped in obtaining peptides with high chelating activity. The understanding of interaction mechanisms has been enhanced through advanced separation techniques and molecular simulation calculations. Optimizing chelation process conditions, including pH and temperature, can help in achieving high binding rates. Methods including phosphorylation modification and ultrasonic treatment can enhance the chelating activity.

Molecular Mechanisms of Iron Transport and Homeostasis Regulated by Antarctic Krill-Derived Heptapeptide-Iron Complex

In this study, the molecular mechanisms of iron transport and homeostasis regulated by the Antarctic krill-derived heptapeptide-iron (LVDDHFL-iron) complex were explored. LVDDHFL-iron significantly increased the hemoglobin, serum iron, total iron binding capacity levels, and iron contents in the liver and spleen to normal levels, regulated the gene expressions of iron homeostasis, and enhanced in vivo antioxidant capacity in iron-deficiency anemia mice (P < 0.05). The results revealed that iron ions within LVDDHFL-iron can be transported via the heme transporter and divalent metal transporter-1, and the absorption of LVDDHFL-iron involved receptor-mediated endocytosis. We also found that the transport of LVDDHFL-iron across cells via phagocytosis was facilitated by the up-regulation of the high mobility group protein, heat shock protein β, and V-type proton ATPase subunit, accompanied by the regulatory mechanism of autophagy. These findings provided deeper understandings of the mechanism of LVDDHFL-iron facilitating iron absorption.

Brain Iron Homeostasis and Mental Disorders

Iron plays an essential role in various physiological processes. A disruption in iron homeostasis can lead to severe consequences, including impaired neurodevelopment, neurodegenerative disorders, stroke, and cancer. Interestingly, the link between mental health disorders and iron homeostasis has not received significant attention. Therefore, our understanding of iron metabolism in the context of psychological diseases is incomplete. In this review, we aim to discuss the pathologies and potential mechanisms that relate to iron homeostasis in associated mental disorders. We propose the hypothesis that maintaining brain iron homeostasis can support neuronal physiological functions by impacting key enzymatic activities during neurotransmission, redox balance, and myelination. In conclusion, our review highlights the importance of investigating the relationship between trace element nutrition and the pathological process of mental disorders, focusing on iron. This nutritional perspective can offer valuable insights for the clinical treatment of mental disorders.

Microencapsulation of Erythrocytes Extracted from Cavia porcellus Blood in Matrices of Tara Gum and Native Potato Starch

Ferropenic anemy is the leading iron deficiency disease in the world. The aim was to encapsulate erythrocytes extracted from the blood of Cavia porcellus, in matrices of tara gum and native potato starch. For microencapsulation, solutions were prepared with 20% erythrocytes; and encapsulants at 5, 10, and 20%. The mixtures were spray-dried at 120 and 140 °C. The iron content in the erythrocytes was 3.30 mg/g and between 2.32 and 2.05 mg/g for the encapsulates (p < 0.05). The yield of the treatments varied between 47.84 and 58.73%. The moisture, water activity, and bulk density were influenced by the temperature and proportion of encapsulants. The total organic carbon in the atomized samples was around 14%. The particles had diverse reddish tonalities, which were heterogeneous in their form and size; openings on their surface were also observed by SEM. The particle size was at the nanometer level, and the zeta potential (ζ) indicated a tendency to agglomerate and precipitation the solutions. The presence of iron was observed on the surface of the atomized by SEM-EDX, and FTIR confirmed the encapsulation due to the presence of the chemical groups OH, C-O, C-H, and N-H in the atomized. On the other hand, high percentages of iron release in vitro were obtained between 88.45 and 94.71%. The treatment with the lowest proportion of encapsulants performed at 140 °C obtained the best results and could potentially be used to fortify different functional foods.