Iron is one of the most important elements for human, because it plays an essential role in many metabolic processes. However, it is also recognized to be dangerous for its detrimental effect inside human cells, where, in the absence of homeostatic balance, it can induce free radicals formation. Moreover, an excessive accumulation of iron in tissues can produce iron overload, a condition incompatible with life. The use of liposomes as carriers can represent an interesting iron therapy to improve iron bioavailability and reduce its negative effects, in particular during pregnancy. In this study, a morphological analysis has been performed on commercial liposome vesicles at various drying times, both in saline solution and in distilled water. Furthermore, to highlight their possible interaction or internalization in cells, liposomes have been administered to human hemopoietic U937 cells. Ultrastructural analyses confirm that vesicle morphology and size are comparable with classical liposomal structures. Products are stable during specimen preparation and drying. Additionally, they have a good ability to penetrate into cells, interacting with cytoplasmic organelles, without inducing, at least apparently, any ultrastructural damage.

The iron bioavailability and acute oral toxicity in rats of a ferrous gluconate compound stabilized with glycine (SFG), designed for food fortification, was studied in this work by means of the prophylactic method and the Wilcoxon method, respectively. For the former studies, SFG was homogenously added to a basal diet of low iron content, reaching a final iron concentration of 20.1 ± 2.4 mg Fe/kg diet. A reference standard diet using ferrous sulfate as an iron-fortifying source (19.0 ± 2.1 mg Fe/kg diet) and a control diet without iron additions (9.3 ± 1.4 mg Fe/kg diet) were prepared in the laboratory in a similar way. These diets were administered to three different groups of weaning rats during 23 d as the only type of solid nourishment. The iron bioavailability of SFG was calculated as the relationship between the mass of iron incorporated into hemoglobin during the treatment and the total iron intake per animal. This parameter resulted in 36.6 ± 6.2% for SFG, whereas a value of 35.4 ± 8.0% was obtained for ferrous sulfate. The acute toxicological studies were performed in 2 groups of 70 female and 70 male Sprague–Dawley rats that were administered increasing doses of iron from SFG. The LD50 values of 1775 and 1831 mg SFG/kg body wt were obtained for female and male rats, respectively, evidencing that SFG can be considered as a safe compound from a toxicological point of view.

The purpose of the present work was to evaluate the iron bioavailability of a new
ferric pyrophosphate salt stabilized and solubilized with glycine. The prophylactic–
preventive test in rats, using ferrous sulfate as the reference standard, was applied as the
evaluating methodology both using water and yogurt as vehicles. Fifty female Sprague–
Dawley rats weaned were randomized into five different groups (group 1: FeSO4; group 2:
pyr; group 3: FeSO4 + yogurt; group 4: pyr + yogurt and group 5: control). The iron
bioavailability (BioFe) of each compound was calculated using the formula proposed by
Dutra-de-Oliveira et al. where BioFe %=(HbFef − HbFei) × 100/ToFeIn. Finally, the
iron bioavailability results of each iron source were also given as relative biological
value (RBV) using ferrous sulfate as the reference standard. The results showed that both
BioFe % and RBV % of the new iron source tested is similar to that of the reference
standard independently of the vehicle employed for the fortification procedure (FeSO4
49.46±12.0% and 100%; Pyr 52.66±15.02% and 106%; FeSO4 + yogurth 54.39±13.92%
and 110%; Pyr + yogurt 61.97±13.54% and 125%; Control 25.30±6.60, p<0.05).
Therefore, the stabilized and soluble ferric pyrophosphate may be considered as an optimal
iron source for food fortification.

Food fortification has shown to be an effective strategy to overcome iron malnutrition. When a new iron compound is developed for this purpose, it must be evaluated from a nutritional and technological point of view before adding it into foods. In this way, we have evaluated ferrous gluconate stabilized by glycine as a new iron source to be used in wheat flour fortification. We performed biological studies in rats as well as sensory perceptions by human subjects in wheat flour fortified with this iron source. The productions of pentane as a rancidity indicator as well as the change of the sensorial properties of the biscuits made with stabilized ferrous gluconate-fortified wheat flour were negligible. Iron absorption in water from this iron source was similar to the reference standard ferrous sulfate. Nevertheless, because of the phytic acid content, iron absorption from fortified wheat flour decrease 40% for both iron sources. The addition of zinc from different sources did not modify iron absorption from ferrous sulfate and stabilized ferrous gluconate in water and wheat flour. The iron absorption mechanism as well as the biodistribution studies demonstrate that the biological behavior of this iron source does not differ significantly from the reference standard. These results demonstrate that the iron source under study has adequate properties to be used in wheat flour fortification. Nevertheless, more research is needed before considering this iron source for its massive use in food fortification.

Food fortification with a proper zinc compound is an economic and effective strategy to prevent zinc
deficiency. BioZn-AAS, a zinc gluconate stabilized with glycine, was compared with zinc sulfate
(reference standard), zinc hydroxide, and zinc gluconate, all of them labeled with ⁶⁵Zn. This preclinical study was performed on Sprague-Dawley rats of both sexes, and the administered dose was 85 mg/kg of zinc. Bioavailability studies showed that absorption of BioZn-AAS was not statistically different than absorption from other sources in female rats (25.65% 6 2.20% for BioZn AAS, 28.24% 6 4.60% for ZnSO4, 24.91% 6 4.02% for Zn[OH]2, and 25.51% 6 2.70% for Zn gluconate). In the case of the male rats, absorption of BioZn-AAS (27.97% 6 4.20%) was higher (P,0.05) than that from the other compounds (23.15% 6 2.90% for ZnSO4, 22.62% 6 3.90% for Zn[OH]2, and 22.30% 6 3.90% for Zn-gluconate). Biodistribution studies demonstrated that the zinc from BioZn-AAS followed the same metabolic pathway as zinc from the other sources. Toxicity studies were performed with 50 female and 50 male rats. The value of oral lethal dose 50 (LD50) was 2000 mg/kg for female rats and 1900 mg/kg for male rats. Therefore, we conclude that BioZn AAS has adequate properties to be considered a proper zinc compound for food fortification or dietary supplementation. 

OBJECTIVE: We investigated the iron bioavailability of microencapsulated ferrous sulfate (SFE-171) in a diet based on powdered milk by using the prophylactic method in rats. METHODS: The SFE-171 was added into fluid milk and industrially processed into powdered milk, which was then mixed in our laboratory with a normalized diet (17.2
2.1 mg Fe/kg). A reference standard diet using ferrous sulfate as iron-fortifying source (19.8
2.9 mg Fe/kg) and a control diet without added iron (4.6
0.8 mg Fe/kg) were prepared in the laboratory in a similar way. These diets were administered to different groups of weaning rats for 28 d as the only solid nourishment. The iron bioavailability of the different sources was calculated as the relation between the mass of iron incorporated into hemoglobin during the treatment and the total iron intake per animal. RESULTS: The iron bioavailability values of SFE-171 and ferrous sulfate in the fortified diets were 41.6
6.6% and 42.6
4.2%, respectively; these results were significantly higher (P  0.01) than the iron bioavailability of the control diet (28.8
8.1%). CONCLUSION: These results showed that iron-fortified powdered milk can be produced from fluid milk fortified with SFE 171. The bioavailability of SFE-171 in this rat model was not altered by the manufacturing process

The behavior of SFE-171 (Biofer^®) used for food fortification was studied. The biological and nutritional properties of this new iron source are discussed in this work.

In this research, we measured the iron bioavailability of ferrous gluconate stabilized with glycine (SFG) when it is used to fortify petit suisse cheese using the prophylactic–preventive method in rats. Three groups of male, weaned rats received a basal diet (control diet; 5.2 ppm Fe), a reference standard diet (SO₄Fe; 9.2 ppm Fe), and a basal diet using iron-fortified petit suisse cheese as the iron source (cheese diet; 8.8 ppm Fe) for 22 d. The iron bioavailability was calculated as the ratio between the mass of iron incorporated into hemoglobin and the total iron intake per animal during the treatment. These values (BioFe) were 68% and 72% for SFG and ferrous sulfate, respectively. The value of the Relative Biological Value (RBV) was 95% for SFG in petit suisse cheese. These results show that according to this method, the iron bioavailability from industrial fortified petit suisse cheese can be considered as a high bioavailability rate.