Use of granules and free salts for Fe and Zn fortification of leafy vegetables: Improvements in trace element bioaccessibility and fulfillment of Dietary Reference Intakes.

BACKGROUND: Leafy vegetables represent an excellent dietary source of trace elements such as Fe and Zn. Nevertheless, Fe and Zn bioaccessibility can lessen due to a high concentration of anti-nutritional compounds. The encapsulation of Fe and Zn salts as granules could be used to fortify these leafy vegetables. METHOD: Three leafy vegetables, spinach, Swiss chard and Ethiopian mustard were fortified with iron sulfate and zinc sulfate as granules and free salts in order to test the improvements in the bioaccessibility and fulfillments of DRIs. Fe and Zn granules were prepared in a fluidized bed granulator. A probabilistic analysis was performed, using experimental data, to assess bioaccessible intake and fulfillments of DRIs in European populations. RESULTS: Fe contents ranged between 4.8 mg/100 g of Ethiopian mustard to 157.4 mg/100 g of spinach. Fe and Zn bioaccessibility percentages were low for Swiss chard and spinach without fortification. Fortification with granules improved Fe bioaccessibility of these latter vegetables (196 and 223 mg/100 g). Zn contents in samples without fortification ranged between 2.3 mg/100 g for Ethiopian mustard and 7.4 mg/100 g for spinach. Zn fortification as granules improved Zn bioaccessibility for the three vegetables studied. Thus, Zn bioccessible concentrations ranged between 17.4 and 108 mg/100 g for the solubility assay and between 5.9 and 31.1 mg/100 g for the dialyzability assay. Besides, the probability analysis showed that fortification had a better performance in meeting DRIs for those populations with higher consumption levels of leafy vegetables. CONCLUSIONS: The probability analysis demonstrated that fortification can be a suitable strategy to meet DRIs for both trace elements, which was especially remarkable for Fe. Fortification with granule was more effective in most the cases, although for Ethiopian mustard, free salt of Fe showed a better performance.

Bioaccessibility of glucosinolates, isothiocyanates and inorganic micronutrients in cruciferous vegetables through INFOGEST static in vitro digestion model.

Green tissues and seeds from cruciferous vegetables growing in conventional and ecological conditions (Brassica carinata; Brassica rapa; Eruca vesicaria and Sinapis alba) were analyzed to determine their contents of glucosinolates, isotihiocyanates (ITCs) and inorganic micronutrients (Ca, Cr, Cu, Fe, Mn, Ni, Se and Zn), and the bioaccessibility of these compounds. Regarding total contents and bioaccessibility values of these compounds, no clear difference was found between the organic and conventional systems. Glucosinolates bioaccessibility present in green tissues were high, with values around 60-78%. In additon, it was quantified in bioaccessible fraction ITCs concentrations such as Allyl - ITC; 3 - Buten - 1 - yl - ITC and 4 - Penten - 1 - yl - ITC. Trace elements bioaccessibility in green tissues was also high for Ca (2.26-7.66 mg/g), Cu (0.60-2.78 µg/g), Se (9.93-74.71 µg/Kg) and Zn (12.98-20.15 µg/g). By contrast, the bioaccessibility of glucosinolates and trace elements in cruciferous seeds was extremely low. With the exception of Cu, these bioaccessibility percentages did not exceed 1% in most cases.

Overcoming glucocorticoid resistances and improving antitumor therapies: lipid and polymers carriers.

PURPOSE: To improve chemotherapy protocols of lymphoid malignancies, by using polymeric and lipid microparticles as controlled delivery systems of dexamethasone, part of all combined chemotherapy protocols for its strong-inducing effect on malignant lymphoblasts. METHODS: Polymeric microparticles were prepared by the oil-in-water-emulsion cosolvent evaporation method, andlipid microparticles by spray drying. Their cytotoxic effects on GC-sensitive PC12 cells and GC-resistant PC3 cells were characterized by cell proliferation and apoptosis assays. RESULTS: Both elaboration methods rendered optimal-sized microparticles for parenteral administration with high drug loading. In vitro assays showed sustained dexamethasone release from polymeric microparticles over a month, whereas 100% dexamethasone release from lipid microparticles was achieved within 24 h. Similar PC12 cell death to that obtained with dexamethasone solution administered every 48 h was achieved with dexamethasone polymeric microparticles in 26-days assays. Dexamethasone solution and loaded polymeric microparticles induced apoptosis around 15.8 and 19.9%, respectively, after 2 days of incubation. Lipid microparticles increased further apoptosis induction in PC12 cells and, unlike dexamethasone solution and polymeric microparticles, showed antiproliferative effects on PC3 cells. CONCLUSIONS: Dexamethasone polymeric microparticles constitute an alternative to current dexamethasone administration systems in combined chemotherapy, whereas dexamethasone lipid microparticles represent a potential tool to revert glucocorticoid resistance.