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Moringa stenopetalais considered a superfood due to the many bioactive compounds that it provides to the diet. However, like all edible plants, it is mandatory to guarantee food safety. Thus it is necessary to develop analytical methods that can rapidly and accurately determine hazardous pollutants, to evaluate compliance with food regulations. In this regard, two multi-component procedures were developed trying to cover some of the main organic and inorganic potential contaminants. A microwave-assisted digestion followed by electrothermal atomic absorption spectrometry was used for arsenic, cadmium, and lead determination, while a modification of the QuEChERS protocol followed by gas chromatography-tandem mass spectrometry was employed for the determination of 55 pesticides from different families. Both analytical methods were thoroughly validated according to international guidelines. The analyzed samples obtained from the Uruguayan market showed compliance with both, national and international, food regulations. The holistic approach employed in this research is not commonly presented in the literature, thus constituting a novel way to face food safety.

The influence of the cooking method on the elemental composition of popcorn, prepared according to the way it is consumed, was evaluated. Arsenic, calcium, cadmium, copper, iron, lead, magnesium, manganese, potassium, selenium, sodium and zinc levels were determined using atomic absorption spectrometry. Results showed that the losses after cooking varied considerably (2.9%–48.3%) depending on the element. A bioaccessibility study of cooked samples was also performed, using an in vitro approach. The most bioaccessible elements were sodium (77.4%–88.5%) and potassium (63.7%–81.8%), while considerably low values were observed for calcium (5.5%–13.7%) probably due to strong interactions with the matrix. The contribution to the Recommended Dietary Allowance was evaluated, finding an important coverage for selenium (36.7%–50.0%). Positive Pearson correlation coefficients were found for the pairs Cu/Fe, Cu/Mn, Fe/Mn Cu/K, Fe/K, K/Mn which can be explained by natural physiological mechanisms of the plant. To the best of our knowledge, this is the first study of bioaccessibility of essential elements in Uruguayan popcorn.

An analytical method for sample preparation and subsequent determination of Cd, Pb and Se in beef using aerosol dilution by inductively coupled plasma-mass spectrometry was developed. The use of high matrix introduction technology allowed the introduction of a complex sample into the plasma with higher content of total dissolved solids a residual acidity of 4% and better tolerance to matrix effects. Trueness was verified by the analysis of two reference materials. At the 95% significance level, results were statistically equivalent to the certified or informed values. Analytical precision expressed as relative standard deviation was less than 9% in all cases. After validation, a total of 12 beef samples from Uruguay were analyzed. Obtained levels for Cd and Pb were far below the maximum limits established by international regulations in all samples. Also, results showed that beef from this region is a good source of Se in the range 0.120–0.870 mg kg−1with an interesting contribution to the daily intake of this essential element.

Human African trypanosomiasis (HAT, sleeping sickness) and American trypanosomiasis (Chagas disease) are endemic zoonotic diseases caused by genomically related trypanosomatid protozoan parasites (Trypanosoma bruceiand Trypanosoma cruzi, respectively). Just a few old drugs are available for their treatment, with most of them sharing poor safety, efficacy, and pharmacokinetic profiles. Only fexinidazole has been recently incorporated into the arsenal for the treatment of HAT. In this work, new multifunctional Ru(II) ferrocenyl compounds were rationally designed as potential agents against these pathogens by including in a single molecule 1,1′-bis(diphenylphosphino)ferrocene (dppf) and two bioactive bidentate ligands: pyridine-2-thiolato-1-oxide ligand (mpo) and polypyridyl ligands (NN). Three [Ru(mpo)(dppf)(NN)](PF6) compounds and their derivatives with chloride as a counterion were synthesized and fully characterized in solid state and solution. They showed in vitroactivity on bloodstream T. brucei(EC50= 31–160 nM) and on T. cruzitrypomastigotes (EC50= 190–410 nM). Compounds showed the lowest EC50values on T. bruceiwhen compared to the whole set of metal-based compounds previously developed by us. In addition, several of the Ru compounds showed good selectivity toward the parasites, particularly against the highly proliferative bloodstream form of T. brucei. Interaction with DNA and generation of reactive oxygen species (ROS) were ruled out as potential targets and modes of action of the Ru compounds. Biochemical assays and in silicoanalysis led to the insight that they are able to inhibit the NADH-dependent fumarate reductase from T. cruzi. One representative hit induced a mild oxidation of low molecular weight thiols in T. brucei. The compounds were stable for at least 72 h in two different media and more lipophilic than both bioactive ligands, mpo and NN. An initial assessment of the therapeutic efficacy of one of the most potent and selective candidates, [Ru(mpo)(dppf)(bipy)]Cl, was performed using a murine infection model of acute African trypanosomiasis. This hit compound lacks acute toxicity when applied to animals in the dose/regimen described, but was unable to control parasite proliferation in vivo, probably because of its rapid clearance or low biodistribution in the extracellular fluids. Future studies should investigate the pharmacokinetics of this compound in vivoand involve further research to gain deeper insight into the mechanism of action of the compounds.