RESUMO
The purpose of this study was to find an alternative application for chrysotile asbestos, given that there is a complete structure of extraction and production of this class of serpentine minerals, but its use is banned for many applications. The idea was to obtain a compound that could immobilize phosphate by triggering a reaction between the magnesium oxide and hydroxide contained in the mineral, without causing phosphate leaching. To this end, chrysotile (Mg3SiO5(OH)4) was treated with phosphoric acid (H3PO4) in a molar ratio of 1:3 in an aqueous medium at 85 °C until the solvent evaporated, resulting in two different solid compounds, which were prepared in a similar manner. The first compound (cri/H3PO4 1:3)1, was obtained by rinsing and then heat-treating it at 150 °C for 6 h, while the second one, (cri/H3PO4 1:3)2, was rinsed after the heat treatment. Compound (cri/H3PO4 1:3)1 underwent partial leaching, while compound (cri/H3PO4 1:3)2 showed a mass increase of 48%, with the formation of crystalline magnesium pyrophosphate mixed with amorphous SiO2. The latter compound adsorbed N-NH3 at pH 10, following the pseudo-first-order model (activation energy = 8329 ± 1696 J mol-1). Equilibrium experiments, which were performed following Hill's sigmoidal type S2 isotherm model, indicated that the adsorption phenomenon was governed by two processes, i.e., complexation up to the inflection point (KH between 10.0 mg L-1 at 40 °C and 13.6 mg L-1 at 25 °C) followed by adsorption. The qmax varied from 18.0 to 19.6 mgN g-1 and the adsorbent was reusable, maintaining its initial adsorbent capacity during its first reuse. This material, which was tested on real effluents, presented a N-NH3 removal rate similar to that shown by the test solutions. The treatment of chrysotile with H3PO4 conducts it to a composite that adsorbs ammoniacal nitrogen at pH 10 and it is reusable maintaining the adsorption capacity.
RESUMO
The widespread use of antibiotics and anti-inflammatory has been more and more prominent. In spite of the proven pharmacological potential, its collateral effects are still being described. The fish oil is made of acids fatty polyunsaturated, as the omega 3. The aim of this paper is to check if there would be interference of this fish oil in the gut microbiota of rats when treated with dexamethasone and amoxicillin, joining with the parameter lipids and glycemic. This study was done with 42 Wistar rats, divided into 6 groups with 7 animals each: naive (CTL), amoxicillin (AMOX), dexamethasone (DEX), fish oil (OLP), associated amoxicillin and fish oil (AMOXâ¯+â¯OLP) association dexamethasone and fish oil (DEXâ¯+â¯OLP). The results show that the fish oil influenced in the concentration of blood glucose in the animals, keeping stable levels even after a pool of glucose. Differently, the fish oil increased the levels of LDL in the animals. The amoxicillin changed the mass of liver and spleen, changed the levels of triglyceride and changed the gut microbiota. The dexamethasone influenced the lipids parameters and mass of the spleen as well as it slightly increased the amount of cholesterol LDL. It is possible to conclude that fish oil increases the levels of LDL in the tested model and the dose tested, but is able to maintain glucose levels even after a pool of the same, and can be a preventive model with hyperglycemia.
