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Background:Stryphnodendron adstringens (Mar.) Coville is a native plant from Brazil, rich in phenolic compounds and used on popular medicine as a wound healing agent, in the treatment of gastric lesions and as antimicrobial.Materials and Methods:Ultrassound-assisted extraction (UAE) was applied to extraction of epigallocatechin gallate (EGCG), total polyphenols (TP) and total tannins (TT) content from barks of Stryphnodendron adstringens (Mar.) Coville. Several operating parameters, namely extraction time (min), liquid to solid ratio (mg/mL), ethanolic strength (%, v/v), were optimized using response surface methodology (RSM) with a Box-Behnken design.Results:By using the desirability function approach, the optimum UAE conditions to obtain desirable extraction yields for all these metabolites simultaneously were found at the extraction time of 30 min, solid to liquid ratio of 4 mg/mL and ethanolic strength of 65. Under these conditions, the epigallocatechin gallate, total polyphenols and total tannins content were 0.31; 22.95 and 11.95 % (w/w), respectively.Conclusion:The results indicated that knowledge gained from this study should be helpful to further exploit and apply this resource and also showed the feasibility of ultrasound-assisted extraction for obtaining GEGC, TP and TT from barks of S. adstrigens.

This work describes the isolation and structural elucidation of compounds from the leaves of Myrcia tomentosa (Aubl.) DC. (goiaba-brava) and evaluates the antimicrobial activity of the crude extract, fractions and isolated compounds against bacteria and fungi. Column chromatography was used to fractionate and purify the extract of the M. tomentosa leaves and the chemical structures of the compounds were determined using spectroscopic techniques. The antibacterial and antifungal activities were assessed using the broth microdilution method. The phytochemical investigation isolated 11 compounds: α-bisabolol, α-bisabolol oxide B, α-cadinol, β-sitosterol, n-pentacosane, n-tetracosane, quercetin, kaempferol, avicularin, juglanin and guaijaverin. The crude ethanolic extract and its fractions were tested against 15 bacteria and 9 yeasts. The crude extract inhibited the in vitro growth of yeasts at concentration of 4 to 32 μg/mL. The hexane, dichloromethane, ethyl acetate and aqueous fractions inhibited Candida sp. at concentrations of 4 to 256 μg/mL, whereas the Cryptococcus sp. isolates were inhibited only by the hexane and dichloromethane fractions in minimal inhibitory concentrations (MICs) at 16 to 64 μg/mL. The flavonoid quercetin-3-O-α-arabinofuranose (avicularin) was the most active compound, inhibiting Candida species in concentrations of 2 to 32 μg/mL. The MIC values suggest potential activity of this plant species against yeast.

Campomanesia adamantium (Myrtaceae) is an antioxidant compounds-rich Brazilian fruit popularly known as gabiroba. In view of this, it was evaluated the hepatoprotective effects of pulp (GPE) or peel/seed (GPSE) hydroalcoholic extracts of gabiroba on injured liver-derived HepG2 cells by CCl4 (4 mM). The results showed the presence of total phenolic in GPSE was (60%) higher when compared to GPE, associated with interesting antioxidant activity using DPPH• assay. Additionally, HPLC chromatograms and thin layer chromatography of GPE and GPSE showed the presence of flavonoids. Pretreatment of HepG2 cells with GPE or GPSE (both at 800–1000 μg/mL) significantly (p < 0.0001) protected against cytotoxicity induced by CCl4. Additionally, the cells treated with both extracts (both at 1000 μg/mL) showed normal morphology (general and nuclear) contrasting with apoptotic characteristics in the cells only exposed to CCl4. In these experiments, GPSE also was more effective than GPE. In addition, CCl4 induced a marked increase in AST (p < 0.05) and ALT (p < 0.0001) levels, while GPE or GPSE significantly (p < 0.0001) reduced these levels, reaching values found in the control group. In conclusion, the results suggest that gabiroba fruits exert hepatoprotective effects on HepG2 cells against the CCl4-induced toxicity, probably, at least in part, associated with the presence of antioxidant compounds, especially flavonoids.

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Alkanolamine + carboxylic acid-based ionic liquids have shown promising high CO 2 selectivities. Their addition to cellulose acetate (CA) and polyvinyl alcohol (PVA) was investigated in the present study. The N-methyl-2-hydroxyethylammonium propionate IL [m-2HEA][Pr] significantly enhances the CO 2 separation performance of PVA. Scanning electron microscopy, Fourier transform infrared spectroscopy, and nuclear magnetic resonance analyses indicate that the IL−PVA combination produced IL composite membranes with interactions being predominantly physical. Furthermore, the IL addition to CA produced porous membranes with apparent low CO 2 separation efficiency. Pure gas permeation experiments indicate that increasing IL concentration of PVA-based membranes promotes higher gas permeabilities. The membranes were prepared containing up to 60.3 wt % of [m-2HEA][Pr], which resisted pressure differentials up to 6 barg. PVA containing 45.5 wt % of IL produced the most promising results, achieving 26 barrer of CO 2 permeability and permselectivities of 122 and 213 for CO 2 /CH 4 and CO 2 /N 2 , respectively. This result was compared to promising materials from the literature and indicated the overall high CO 2 /CH 4 and CO 2 / N 2 selectivities of PVA/[m-2HEA][Pr] membranes, which overcome even the 2008 Robeson's upper boundary.

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