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Traditionally, Ilex paraguariensis leaves are consumed in tea form or as typical drinks like mate and terere, while the fruits are discarded processing and has no commercial value. The aim of this work to evaluate phytochemical properties, total phenolic compounds, antioxidant and antimicrobial activity of extracts of Ilex paraguariensis fruits obtained from supercritical CO2 and compressed propane extraction. The extraction with compressed propane yielded 2.72 wt%, whereas with supercritical CO2 1.51 wt% was obtained. The compound extracted in larger amount by the two extraction solvents was caffeine, 163.28 and 54.17 mg/g by supercritical CO2 and pressurized propane, respectively. The antioxidant activity was more pronounced for the supercritical CO2 extract, with no difference found in terms of minimum inhibitory concentration for Staphylococcus aureus for the two extracts and better results observed for Escherichia coli when using supercritical CO2.

This work reports experimental data on dry-washing of biodiesel produced by enzyme-catalyzed reaction using ion exchange resins, a commercial immobilized enzyme, and a magnesium silicate adsorbent. Experiments were carried out in continuous-mode packed-bed column, varying operating temperature and pressure, and residence time toward reaching the current specifications of the biodiesel samples tested. Besides, the amounts of free fatty acids (FFA), raw material, and products were characterized with regard to the content of monoacylglycerol (MAG), diacylglycerol (DAG), and triacylglycerol (TAG). It is shown that resins and the immobilized enzyme presented, to a certain extent, satisfactory results, in terms of FFA reduction, while the use of the adsorbent allowed reaching “on spec” biodiesel. It was observed that the water content dramatically affected the quality of the final product, which severely hindered one from reaching lower FFA contents. Integration of resins together with silicate adsorbent seems ...

Traditionally, Ilex paraguariensis leaves are consumed in tea form or as typical drinks like mate and terere, while the fruits are discarded processing and has no commercial value. The aim of this work to evaluate phytochemical properties, total phenolic compounds, antioxidant and antimicrobial activity of extracts of Ilex paraguariensis fruits obtained from supercritical CO2 and compressed propane extraction. The extraction with compressed propane yielded 2.72 wt%, whereas with supercritical CO2 1.51 wt% was obtained. The compound extracted in larger amount by the two extraction solvents was caffeine, 163.28 and 54.17 mg/g by supercritical CO2 and pressurized propane, respectively. The antioxidant activity was more pronounced for the supercritical CO2 extract, with no difference found in terms of minimum inhibitory concentration for Staphylococcus aureus for the two extracts and better results observed for Escherichia coli when using supercritical CO2.

This work investigates the use of ceramic membranes with different molecular weight cut-offs (MWCOs: 5, 10 and 20 kDa) to desolventize azeotropic solvent mixtures (ethanol/n-hexane and isopropyl alcohol/n-hexane) from soybean oil/azeotrope micelles. Results show that a decrease in the MWCO of a membrane and an increase in the solvent mass ratio in the mixture resulted in a significant reduction in the permeate flux. The 20 kDa membrane presented the highest permeate flux, 80 and 60 kg/m2h for the soybean oil/n-hexane/isopropyl alcohol and soybean oil/n-hexane/ethanol azeotropes, respectively, for an oil to solvent ratio of 1:3 (w/w). The highest oil retention was found using the n-hexane/isopropyl alcohol azeotrope, around 25% in the membrane with the lowest MWCO, that is, 5 kDa. It is shown that the azeotropic mixtures provided intermediate characteristics compared to the original pure solvent behavior.