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This study investigated the in vitro bioaccessibility of aluminum, copper, iron, manganese, lead, selenium, and zinc in three important species of farmed insects: the yellow mealworm (Tenebrio molitor) , the house cricket (Acheta domesticus) and the migratory locust (Locusta migratoria). Results show that all three insect species constitute excellent sources of essential elements (Fe, Cu and Zn) for the human diet, contributing to the recommended dietary allowance, i.e. , 10%, 50%, and 92%, respectively. A higher accumulation of Se (≥1.4 mg Se/kg) was observed with increasing exposure concentration in A. domesticus , showing the possibility of using insects as a supplements for this element. The presence of Al and Fe nanoparticles was confirmed in all three species using single particle-inductively coupled plasma-mass spectrometry and transmission electron microscopy. The results also indicate that Fe bioaccessibility declines with increasing Fe-nanoparticle concentration. These findings contribute to increase the nutritional and toxicological insights of farmed insects. • Studied insects provide excellent sources of Fe, Cu, and Zn for the human diet. • Selenium-enriched diets significantly boost selenium levels in A. domesticus. • A higher presence of Fe-nanoparticles reduced Fe bioaccessibility. • Whether as nanoparticles or in ionic form, Al bioaccessibility remains below 10%. [ABSTRACT FROM AUTHOR]

Aiming to select the most suitable sample preparation for the multiresidue analysis of pesticides in globe artichoke ( Cynara cardunculus L.), a modified QuEChERS, a matrix solid phase dispersion and a dispersive ethyl acetate extraction were compared. Trueness and precision were determined at 0.2 mg kg −1 for the three methods. The modified QuEChERS showed the best performance. The scope of the method was enlarged to 35 GC and 63 LC amenable pesticides, its overall performance was evaluated and validated to artichoke leaves and fruits according to DG-SANTE Guidelines. Different matrix effects were observed for most of the pesticides which were higher for leaves than fruits. Difenoconazole and flutriafol suffered signal suppression in leaves extracts but showed positive matrix effects in fruits. All pesticides were analyzed at or below their Maximum Residue Levels fixed for globe artichoke by the European Union. The method was successfully applied for the analysis of commercial samples. [ABSTRACT FROM AUTHOR]

American Trypanosomiasis is a chronic infection discovered and described in 1909 by the Brazilian scientist Carlos Chagas. It is caused by the protozoan parasite Trypanosoma cruzi . Although it affects about 10 million people in Latin America, the current chemotherapy is still inadequate. The discovery of new drugs is urgently needed. Our group is focused on the development of prospective metal-based drugs mainly based on bioactive ligands and pharmacologically interesting metal ions. In this work three new rhenium(I) tricarbonyl compounds fac -[Re I (CO) 3 Br(HL)] where HL = 5-nitrofuryl containing thiosemicarbazones were synthesized and fully characterized in solution and in the solid state. The in vitro evaluation of the compounds on T. cruzi trypomastigotes (Dm28c strain) showed that the Re(I) compounds are 8 to 15 times more active than the reference drug Nifurtimox and show a 4 to 17 fold increase in activity in respect to the free (HL) ligands. Obtained compounds also show good selectivity indexes (IC 50 endothelial cells Ea.hy926 /IC 50 T. cruzi (Dm28c tripomastigotes) ). 1 H NMR and MS studies, performed with time, showed that the fac -[Re(CO) 3 Br(HL)] species convert into the dimers [Re 2 (CO) 6 (L) 2 ] in solution. Crystal structure of [Re I 2 (CO) 6 ( L2 ) 2 ], the product of complexes' dimerization, was solved. Related to the mechanism of action, the studied compounds do not generate radical oxygen species in the parasite (as 5-nitrofuryl derived thiosemicarbazones do) probably due to the unfavorable nitro reduction potential of the generated dimeric species. On the contrary, the compounds produce a decrease of the oxygen consumption rate of the parasites, maybe inhibiting their mitochondrial respiration. [ABSTRACT FROM AUTHOR]

A simple and fast ultrasound-assisted procedure for the determination of iron and zinc in infant formulas is presented. The analytical determinations were carried out by flame atomic absorption spectrometry. Multivariate experiments were performed for optimization; in addition, a comparative study was carried out using two ultrasonic devices. A method using an ultrasonic bath was selected because several samples can be prepared simultaneously, and there is less contamination risk. Analytical precision (sr(%)) was 3.3% and 4.1% for iron and zinc, respectively. Trueness was assessed using a reference material and by comparison of the results obtained analyzing commercial samples using a reference method. The results were statistically equivalent to the certified values and in good agreement with those obtained using the reference method. The proposed method can be easily implemented in laboratories for routine analysis with the advantage of being rapid and in agreement with green chemistry. [ABSTRACT FROM AUTHOR]

In the search for new therapeutic tools against tuberculosis and to further address the therapeutic potential of pyridine-2-thiol 1-oxide (Hmpo) metal complexes, two new octahedral [M III (mpo) 3 ] complexes, with M = Ga or Bi, were synthesized and characterized in the solid state and in solution. Attempts to crystallize [Ga III (mpo) 3 ] in CH 2 Cl 2 led to single crystals of the reaction product [GaCl(mpo) 2 ], where the gallium(III) ion is in a square basis pyramidal environment, trans -coordinated at the basis to two pyridine-2-thiolato 1-oxide anions acting as bidentate ligands through their oxygen and sulfur atoms. The biological activity of the new [M III (mpo) 3 ] complexes together with that of the previously reported Fe(III) analogous compound and the pyridine-2-thiol 1-oxide sodium salt (Na mpo) was evaluated on Mycobacterium tuberculosis . The compounds showed excellent activity, both in the standard strain H 37 Rv ATCC 27294 (pan-susceptible) and in five clinical isolates that are resistant to the standard first-line anti-tuberculosis drugs isoniazid and rifampicin. These pyridine-2-thiol 1-oxide derivatives are promising compounds for the treatment of resistant tuberculosis. [ABSTRACT FROM AUTHOR]

The globe artichoke ( Cynara cardunculus L. subsp. cardunculus ) is a perennial plant cultivated in the Mediterranean region and Americas for its edible young flower heads and as an interesting source of bioactive compounds. The present study was undertaken to evaluate scavenging capacity against the most physiologically relevant reactive oxygen species (ROS) and reactive nitrogen species (RNS) of three different extracts from artichoke leaves (infusion, decoction and hydroalcoholic) using different solvents, commonly accepted for human consumption (water and a mixture of ethanol/water). Additionally, the phenolic compounds in each extract were identified and quantified by high performance liquid chromatography coupled to diode array and mass spectrometer detectors (HPLC–DAD–MS/MS). Chlorogenic acid was the major phenolic compound identified in all extracts, followed by 1,3-dicaffeoylquinic acid (cynarin), luteolin-7-rutinoside and the infusion extract presented the highest phenolic content (108 mg/g extract, dry basis). In general, the extracts of artichoke leaves presented a remarkable capacity to scavenge ROS and RNS with IC 50 values in a low μg/mL range (3.4–43 μg/mL). These findings suggest that artichoke could be a potential source of natural antioxidants and has an undeniable nutraceutical value. [ABSTRACT FROM AUTHOR]

Microwave induced plasma atomic emission spectrometry (MP-AES) was evaluated as a strategy for the analysis of simulated gastrointestinal solutions to estimate the in vitro bioaccessibility of essential elements in cooked pink shrimp. Operational conditions such as pump speed, nitrogen flow, and viewing position were thoroughly optimized for each element. Afterwards the validation of the analytical method was performed. Limits of quantification ranged from 0.005 mg kg−1 (Mn) to 0.106 mg kg−1 (Zn). Accuracy was evaluated by using a certified reference material and performing a mass-balance study. Suitable mass balances within the range 95–105% were obtained. In vitro bioaccessibility in cooked shrimp samples ranged from 14.7% (Fe) to 48.1% (Zn), in agreement with previous data from other shrimp species. The proposed procedure proved to be an outstanding sequential analytical strategy for elemental bioaccessibility studies, providing simplicity and high sample throughput compared to conventional approaches. Furthermore, this work constitutes the first work regarding the optimization of an elemental bioaccessibility study on animal protein employing MP-AES. [Display omitted] • The new method for elemental bioaccessibility studies was very efficient and robust. • The thorough optimization of operational conditions for MP-AES determinations was key. • Accuracy was evaluated using a certified reference material and a mass-balance study. • Suitable mass balances within the range 95–105% were obtained after validation. • In vitro bioaccessibility of shrimp samples ranged from 14.7% (iron) to 48.1% (zinc). [ABSTRACT FROM AUTHOR]

Human African trypanosomiasis (sleeping sickness) and leishmaniasis are prevalent zoonotic diseases caused by genomically related trypanosomatid protozoan parasites (Trypanosoma brucei and Leishmania spp). Additionally, both are co-endemic in certain regions of the world. Only a small number of old drugs exist for their treatment, with most of them sharing poor safety, efficacy, and pharmacokinetic profiles. In this work, new multifunctional Ru(II) ferrocenyl compounds were rationally designed as potential agents against these trypanosomatid parasites by including in a single molecule 1,1′-bis(diphenylphosphino)ferrocene (dppf) and two bioactive bidentate ligands: 8-hydroxyquinoline derivatives (8HQs) and polypyridyl ligands (NN). Three [Ru(8HQs)(dppf)(NN)](PF 6) compounds were synthesized and fully characterized. They showed in vitro activity on bloodstream Trypanosoma brucei (IC 50 140–310 nM) and on Leishmania infantum promastigotes (IC 50 3.0–4.8 μM). The compounds showed good selectivity towards T. brucei in respect to J774 murine macrophages as mammalian cell model (SI 15–38). Changing hexafluorophosphate counterion by chloride led to a three-fold increase in activity on both parasites and to a two to three-fold increase in selectivity towards the pathogens. The compounds affect in vitro at least the targets of the individual bioactive moieties included in the new chemical entities: DNA and generation of ROS. The compounds are stable in solution and are more lipophilic than the free bioactive ligands. No clear correlation between lipophilicity, interaction with DNA or generation of ROS and activity was detected, which agrees with their overall similar anti-trypanosoma potency and selectivity. These compounds are promising candidates for further drug development. [Display omitted] • Multifunctional Ru Fe compounds were synthesized and characterized. • They show in vitro activity on Trypanosoma brucei and Leishmania infantum. • Interaction with DNA was stated by fluorescence and gel electrophoresis studies. • Compounds generated ROS in Leishmania infantum promastigotes. • Stability in DMSO-tris buffer pH 7.4 was stated for at least 72 h by HPLC. [ABSTRACT FROM AUTHOR]