A porous graphite (PG) is proposed as anode electrocatalyst of microbial fuel cell (MFC), which is synthesized by thermally decomposing ferrous gluconate followed by leaching iron. The physical characterizations from scanning electron microscopy, Brunauer-Emmett-Teller, X-ray diffraction, Raman spectroscopy, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy, indicate that the resulting PG is mesopore-rich and exhibits high graphitization with oxygen-containing functional groups. When evaluated on a naked carbon felt (NCF) anode, the resulting PG provides the MFC based on Escherichia coli with excellent power output. The MFC using the carbon felt anode loaded with 3.0 mg cm-2 PG delivers a maximum power density of 2.6 W m-2, compared to the 0.2 W m-2 for the MFCs using NCF anode. This excellent performance is attributed to the electronically conductive graphite and porous structure of the resulting PG. The former provides the anode with high activity towards redox reactions of c-type cytochromes in bacteria, the latter stimulates bacteria to produce their flagella that help bacteria to firmly bond each other.

Iron deficiency anemia is a common clinical condition often treated with tablets containing 65 mg of elemental iron. Such doses can elicit gastrointestinal side effects lowering patient compliance. Oral iron supplements also increase hepcidin production causing decreased fractional absorption of subsequent doses. Frequent blood donors often become iron deficient. Therefore, they were enrolled in a two-year study involving continued blood donations and randomization to receive no pill, placebo, 19, or 38 mg ferrous gluconate for 60 days. Total body iron (TBI) did not change for the subset of donors in the no pill and placebo groups who completed both enrollment and final visits (P = .21 and P = .28, respectively). However, repeated measures regression analysis on the complete dataset estimated a significant decrease in TBI of 52 mg/year for the placebo and no pill groups (P = .001). The effects of 19 and 38 mg iron supplementation on TBI were indistinguishable (P = .54). TBI increased by 229 mg after the initial 60 days of iron supplementation (P < .0001) and was maintained at this higher level with continued iron supplementation following each subsequent donation. The TBI increase was apportioned 51 mg to red cell iron (P < .0001) and 174 mg to storage iron (P < .0001). Changes in storage iron were negatively impacted by 57 mg due to concurrent antacid use (P = .04). These findings in blood donors suggest that much lower doses of iron than are currently used will be effective for clinical treatment of iron deficiency anemia.

Antianemic medicament ferrous gluconate, ferrous fumarate, and a Dynabi tablet with a basic iron bearing ingredient were studied with the use of Mössbauer spectroscopy. Room temperature spectra of ferrous gluconate gave clear evidence that the two phases of iron were present: ferrous (Fe(2+)) as a major one with a contribution at and above 91 a.u.% and ferric (Fe(3+)) whose contribution was found to be ~9 a.u.%. In the case of ferrous fumarate, a single phase was measured corresponding to ferrous (Fe(2+)) state. A Dynabi tablet consists of ferrous fumarate and ferrous fumarate. The ferric phase in ferrous gluconate is able to be reached about ~3.6 a.u.% in a tablet.

One of the causes of iron deficiency in human is poor absorption of non-heme iron from the diet. While proteins from meats have been reported in the literature to enhance the absorption of non-heme iron, other proteins, such as those from egg, are known to inhibit iron absorption. The objective of this study is to investigate non-heme iron binding property of egg white proteins hydrolyzed using pepsin and a combination of bacterial/fungal proteases. The iron bioavailability of non-heme iron, in the presence of egg white (EW) hydrolysates, was evaluated in vitro using a tissues culture model system - rat intestinal epithelial cells (IEC-6). In the first treatment condition, EW was digested in the presence of ferrous gluconate (FeGluc), producing a peptide-FeGluc complex. In the second treatment, EW was digested in the absence of FeGluc followed by the addition of the non-heme iron. In both treatments, the resulting EW hydrolysates were further separated into >0.1-0.5kDa and >6-8kDa peptide fractions using dialysis. The hydrolysate and FeGluc complex or mixtures were applied to the IEC-6 cells and iron absorption was measured after 2h or 16h. Results showed that the peptide-FeGluc complex digested with a combined proteases from Bacillus licheniformis (SDAY) and from Aspergillus melluss (PP) increased the in vitro iron-binding property but did not enhance iron uptake by the in IEC-6 cells (p<0.05). Peptide-FeGluc complex digested with pepsin alone (>0.1-0.5kDa) resulted in significantly higher iron uptake in IEC-6 cells compared with the higher molecular weight complex (>6-8kDa) produced using the same hydrolysis treatment. Similarly, enhanced iron uptake was observed with the complexes produced with the combined SDAY and PP enzymatic treatments (>0.1-0.5kDa and >6-8kDa) (p<0.05). On the other hand, the enhanced iron absorption effect was not observed when pre-hydrolyzed free peptides were added to FeGluc. Overall, this study suggests that low molecular weight fractions of egg white protein hydrolysates can enhance the bioavailability of non-heme iron. Furthermore, the method by which the egg white proteins are being prepared, i.e., in the presence or absence of FeGluc, can affect the bioavailability of the non-heme iron.

It is urgent to develop new kinds of low-cost and high-performance nonprecious metal (NPM) catalysts as alternatives to Pt-based catalysts for oxygen reduction reaction (ORR) in fuel cells and metal-air batteries, which have been proved to be efficient to meet the challenge of increase of global energy demand and CO2 emissions. Here, an economical and sustainable method is developed for the synthesis of Fe, N codoped carbon nanofibers (Fe-N/CNFs) aerogels as efficient NPM catalysts for ORR via a mild template-directed hydrothermal carbonization (HTC) process, where cost-effective biomass-derived d(+)-glucosamine hydrochloride and ferrous gluconate are used as precursors and recyclable ultrathin tellurium nanowires are used as templates. The prepared Fe/N-CNFs catalysts display outstanding ORR activity, i.e., onset potential of 0.88 V and half-wave potential of 0.78 V versus reversible hydrogen electrode in an alkaline medium, which is highly comparable to that of commercial Pt/C (20 wt% Pt) catalyst. Furthermore, the Fe/N-CNFs catalysts exhibit superior long-term stability and better tolerance to the methanol crossover effect than the Pt/C catalyst in both alkaline and acidic electrolytes. This work suggests the great promise of developing new families of NPM ORR catalysts by the economical and sustainable HTC process.

The use of self-medication, which includes dietary supplements and over-the-counter drugs, is still on the rise, while safety issues are not well addressed yet. This especially holds for combinations. For example, iron supplements and magnesium peroxide both produce adverse effects via the formation of reactive oxygen species (ROS). This prompted us to investigate the effect of the combination of three different iron supplements with magnesium peroxide on ROS formation. Hydroxyl radical formation by the three iron supplements either combined with magnesium peroxide or alone was determined by performing a deoxyribose assay. Free iron content of iron supplements was determined using ferrozine assay. To determine hydrogen peroxide formation by magnesium peroxide, a ferrous thiocyanate assay was performed. Finally, electron spin resonance spectroscopy (ESR) was performed to confirm the formation of hydroxyl radicals. Our results show that magnesium peroxide induces the formation of hydrogen peroxide. All three iron supplements induced the formation of the extremely reactive hydroxyl radical, although the amount of radicals formed by the different supplements differed. It was shown that combining iron supplements with magnesium peroxide increases radical formation. The formation of hydroxyl radicals after the combination was confirmed with ESR. All three iron supplements contained labile iron and induced the formation of hydroxyl radicals. Additionally, magnesium peroxide in water yields hydrogen peroxide, which is converted into hydroxyl radicals by iron. Hence, iron supplements and magnesium peroxide is a hazardous combination and exemplifies that more attention should be given to combinations of products used in self-medication.