Interaction of iron(III) with taste enhancers:Potential of Fe(III) salts with inosine monophosphate or guanosine monophosphate for food fortification

Iron interactions in iron-fortified savory concentrates lead to undesirable discoloration, even when poorly-water soluble iron salts such as ferric pyrophosphate (Fe4PP3) are used. This is the first study to comprehensively investigate the interaction of Fe(III) with three common taste enhancers: glutamate (Glu), inosine monophosphate (IMP), and guanosine monophosphate (GMP). The stability of the complexes of Fe(III) with IMP or GMP is higher compared to that with Glu. Neutrality of IMP or GMP species with Fe(III) at pH 3–8 resulted in precipitation. This property was exploited to synthesize Fe(III) salts of IMP or GMP (i.e. Fe2IMP3 and Fe2GMP3) by aqueous chemical precipitation. Iron dissolution from Fe2IMP3 and Fe2GMP3 was up to twenty-fold higher at gastric pH (1–3), indicative of better bio-accessibility, and up to fifteen-fold lower at food pH (3–7), indicative of decreased reactivity in food, compared to Fe4PP3. Consequently, Fe2IMP3 and Fe2GMP3, compared to Fe4PP3, led to less discoloration in combination with the poorly soluble phenolics that are commonly present in savory concentrates. We conclude that Fe(III) salts of IMP or GMP can potentially serve as iron fortificants due to their increased solubility at gastric pH (1–3), decreased iron dissolution at food pH (3–7), and decreased reactivity at food pH.</p

An iron-based molecular redox switch as a model for iron release from enterobactin via the salicylate binding mode

L

Using archived FFPE samples for retrospective miRNA expression profiling of blastemal Wilms’ tumors by qRT-PCR

Introduction: Wilms’ tumor is the most frequent genitourinary malignancy in young children. A high percentage of blastema after pre-operative chemotherapy (according to the SIOP protocol) is a sign of poor prognosis. Differences between miRNA signatures of blastemal and regressive tumor subtypes may hold relevant information on genetic factors underlying chemo-responsiveness.Materials and Methods: We extracted miRNA from two FFPE samples per patient: a tumor sample and a tumor-free region of the same kidney to be used as control. A PCR array was used to reveal miRNAs of interest in the first patient and the expression of selected miRNAs was studied in seven other patients by individual qRT-PCR primers.Results: MiRNA expression patterns obtained from FFPE samples showed a close resemblance to the results of previous profiling reports using fresh-frozen tissue. Relevant differences include miR-184 found to be more underexpressed than expected, and miR-203a, which we report to be downregulated in Wilms’ tumor for the first time to our knowledge.Conclusions: Despite favorable reviews in the literature with respect to various diseases, miRNA expression analyses from FFPE samples are still rarely reported. We hereby demonstrate the usefulness of pathological archives in Wilms’ tumor profiling. Putting our results in perspective with literature data, miR-184 seems to be underexpressed in a subset of blastemal and possibly other Wilms’ tumors. Downregulation of miR-203a may or may not be specific to blastemal tissue, but it could explain the overexpression of E2F3 thought to be important in the pathogenesis of the disease