Influence of different types of acids and pH in the recovery of bioactive compounds in Jabuticaba peel (Plinia cauliflora).

Jabuticaba peel presents a high content of bioactive compounds such as phenolic acids, flavonoids, and anthocyanins, normally considered as a food residue. Nowadays, there is a great interesting in the recovery of bioactive compounds from food residue due to health benefits of the ingredients produced, environmental issues and economic aspects. For the success of phenolic compounds extraction, the solvent and pH influence recovery of these compounds. However, studies that evaluate the use of different weak acids bioactive compounds recovery are scarce. Thus, the aim of the present work was to evaluate the effect of formic, acetic, and phosphoric acids addition in the extraction solvent, to adjust the pH to 1.0, 2.0 and 3.0, in bioactive compounds recovery and antioxidant capacity of jabuticaba peel. The extracts were analyzed as antioxidant capacity (ORAC, FRAP), total phenols content monomeric anthocyanin's and a qualitative analysis of phenolics by Liquid Chromatography with mass spectrometry (LC-MS). The kind of acid used in the extraction process affected mainly in the extraction of anthocyanins. The acid that presented a better recovery of anthocyanin (3.4 mg/g raw material) and a better antioxidant capacity (ORAC) (841 µmol TE/g raw material) was formic acid in pH 1.0.

Determination of acetate and formate in vegetable oils by ion chromatography after multivariate optimization of the extraction process using a Doehlert design.

In this work, we present the development of a method for the determination of acetate and formate in vegetable oils by ion chromatography with conductometric detection following their extraction from samples using a diluted KOH solution. The extraction procedure was optimized using a multivariate approach. The application of a 24 full factorial design showed that the mass of sample, extraction time, and KOH concentration presented significant influence on the extraction of both acetate and formate, whereas the temperature presented little influence on the process. As a result, we set the extraction temperature at 22 °C and performed the multivariate optimization of the other variables using a Doehlert design. The optimum conditions were: 4.8 g of sample, 8 mmol L-1 KOH solution and 19 min extraction time. Six samples of vegetable oils (soybean, corn, canola, sunflower and olive) were analyzed and recovery tests provided recovery percentages in the range of 82-118%.

Analysis of the lignocellulosic components of biomass residues for biorefinery opportunities.

The present study aims to identify the renewable resources available in Brazil such as açai seed, coconut husks, coffee husks, rice husks, eucalyptus sawdust, grass, soy peel, bamboo, banana stems and banana stalks. To identify such renewable energy sources, samples were examined for their physical and chemical characteristics using X-ray diffraction (XRD), proximate and ultimate analyses, thermogravimetric analysis (TGA), calorific value determination, near-infrared (NIR) spectroscopy, UV spectroscopy, high-pH anion-exchange chromatography (HPAEC-PAD) and accelerated solvent extraction (ASE). Among the biomasses, açai and coffee exhibited higher total sugar content, 67.70% and 62.55%, respectively. Sawdust exhibited low ash, along with the highest calorific value and lignin content. The highest glucose contents were observed in bamboo (44.65%) and sawdust (38.80%). The maximum yield for the bioproducts levulinic acid (LA), formic acid (FA) and furfural were estimated; açai exhibited the highest yield of LA and FA, while coffee exhibited the best furfural yield. All of these properties indicate that the residues are potential candidates for bioenergy production.

Performic acid for advanced wastewater disinfection.

The disinfection efficiency of performic acid (PFA) against various microbial contaminants has been studied in municipal secondary effluent. The study demonstrated that PFA provides rapid, efficient and safe disinfection, degrading both bacteria and viruses even at low doses. The resistance order starting from the most resistant microorganism is as follows: MS2-coliphages > DNA-coliphages > enterococci and Escherichia coli. PFA is also efficient in the elimination of Salmonella spp., Clostridium perfringens spores and Giardia cysts. The results showed that a PFA dose as low as 0.5-1 mg L(-1) with contact time of 10 min was efficient in achieving and maintaining for 72 h the disinfection level required for unrestricted agricultural water reuse (≤3 log units for faecal coliforms). However, the optimal dose will depend on the quality of wastewater. Regarding the formation of by-products during disinfection with PFA, very low amounts of hydrogen peroxide and organic per-acids were observed; active oxygen was not detected. The amounts of adsorbable organically bound halogens (AOX) compounds formed were significantly lower compared to the amounts generated during chlorine disinfection. This chlorine-free solution enables compliance with microbiological criteria for various water reuse applications and is already on the market for advanced disinfection.

Capillary electrophoresis with capacitively coupled contactless conductivity detection applied to the quantitation and to the determination of physical-chemical properties of peroxycarboxylates in aqueous medium.

CE with C4D (CE-C4D) was successfully applied to the investigation of performate, peracetate, and perpropionate in aqueous medium. Ionic mobilities, diffusion coefficients, and hydrodynamic radii were obtained for the first time for these species. CE-C4D was also used to estimate the pKa values of the peroxycarboxylic acids. Because the peroxycarboxylates (POCs) undergoes hydrolysis while migrating, a simple calibration curve cannot be used for quantitation. Thus, an indirect calibration approach was used. The new method was used to monitor the formation of peroxycarboxylic acids from hydrogen peroxide and the carboxylic acid as well as to the quantitation of peracetic acid in a commercial sample. The CE-C4D method compares favorably with the conventional titration method because of the possibility of speciation of the POC, the low sample consumption, and the low LOD (14, 8, and 24 µmol/L for performate, peracetate, and perpropionate, respectively). Although POCs are structural isomers of monoalkyl carbonates, they have greater hydrodynamic radii, which suggests that the positions of the oxygen atoms in the molecules have a direct impact in the charge density and consequently on the hydration atmosphere.

Indoor air quality of a museum in a subtropical climate: the Oscar Niemeyer museum in Curitiba, Brazil.

The assessment of damage to indoor cultural heritage, in particular by pollutants, is nowadays a major and growing concern for curators and conservators. Nevertheless, although many museums have been widely investigated in Europe, the effects of particulate matter and gaseous pollutants in museums under tropical and subtropical climates and with different economic realities are still unclear. An important portion of the world's cultural heritage is currently in tropical countries where both human and financial resources for preserving museum collections are limited. Hence, our aim is to assess the damage that can be caused to the artwork by pollution in hot and humid environments, where air quality and microclimatic condition differences can cause deterioration. As a case study, particulate matter as well as gases were collected at the Oscar Niemeyer Museum (MON) in Curitiba, Brazil, where large modern and contemporary works of art are displayed. NO2, SO2, O3, Acetic Acid, Formic Acids and BTEX, in the ambient air, were sampled by means of passive diffusive sampling and their concentrations were determined by IC or GC-MS. The particulate matter was collected in bulk form and analyzed with the use of energy dispersive X-ray fluorescence and aethalometer. The chemical compositions of individual particles were quantitatively elucidated, including low-Z components like C, N and O, as well as higher-Z elements, using automated electron probe microanalysis. The gaseous and particulate matter levels were then compared with the concentrations obtained for the same pollutants in other museums, located in places with different climates, and with some reference values provided by international cultural heritage conservation centers. Results are interpreted separately and as a whole with the specific aim of identifying compounds that could contribute to the chemical reactions taking place on the surfaces of artifacts and which could potentially cause irreversible damage to the artworks.

Versatile microanalytical system with porous polypropylene capillary membrane for calibration gas generation and trace gaseous pollutants sampling applied to the analysis of formaldehyde, formic acid, acetic acid and ammonia in outdoor air.

The analytical determination of atmospheric pollutants still presents challenges due to the low-level concentrations (frequently in the µg m(-3) range) and their variations with sampling site and time. In this work, a capillary membrane diffusion scrubber (CMDS) was scaled down to match with capillary electrophoresis (CE), a quick separation technique that requires nothing more than some nanoliters of sample and, when combined with capacitively coupled contactless conductometric detection (C(4)D), is particularly favorable for ionic species that do not absorb in the UV-vis region, like the target analytes formaldehyde, formic acid, acetic acid and ammonium. The CMDS was coaxially assembled inside a PTFE tube and fed with acceptor phase (deionized water for species with a high Henry's constant such as formaldehyde and carboxylic acids, or acidic solution for ammonia sampling with equilibrium displacement to the non-volatile ammonium ion) at a low flow rate (8.3 nL s(-1)), while the sample was aspirated through the annular gap of the concentric tubes at 2.5 mL s(-1). A second unit, in all similar to the CMDS, was operated as a capillary membrane diffusion emitter (CMDE), generating a gas flow with know concentrations of ammonia for the evaluation of the CMDS. The fluids of the system were driven with inexpensive aquarium air pumps, and the collected samples were stored in vials cooled by a Peltier element. Complete protocols were developed for the analysis, in air, of NH(3), CH(3)COOH, HCOOH and, with a derivatization setup, CH(2)O, by associating the CMDS collection with the determination by CE-C(4)D. The ammonia concentrations obtained by electrophoresis were checked against the reference spectrophotometric method based on Berthelot's reaction. Sensitivity enhancements of this reference method were achieved by using a modified Berthelot reaction, solenoid micro-pumps for liquid propulsion and a long optical path cell based on a liquid core waveguide (LCW). All techniques and methods of this work are in line with the green analytical chemistry trends.

Degradation of a mixture of pollutants in water using the UV/H2O2 process.

The degradation reaction of a simple mixture of pollutants (dichloroacetic acid + formic acid) employing H2O2 and UVC radiation (253.7 nm) has been studied in a well-mixed reactor which operates inside a recycling system. The aim of this work is to develop a systematic methodology for treating degradation of mixtures of pollutants, starting from a rather manageable system to more complex aggregates. In this contribution, the effects of different variables such as hydrogen peroxide/pollutant mixture initial concentration ratio, pH and incident radiation at the reactor wall were studied. The results show that the best degrading conditions are: pH = 3.5 and hydrogen peroxide concentrations from 3.9 to 11.8 mM (134-400 mg/L), for initial concentrations of 1.10 and 0.39 mM for formic acid and dichoroacetic acid respectively (50 mg/L for both pollutants). The influence of the incident radiation at the reactor wall on the degradation rates of the mixture is significant. In addition to this, it has been shown that in the employed aqueous solution no stable reaction intermediates are formed. On this basis, a complete reaction scheme for the mixture is proposed that is suitable for a reaction kinetics mathematical modeling of the mixture and further studies of increasing complexity.

Validation of a liquid chromatographic/tandem mass spectrometric method for the determination of scopolamine butylbromide in human plasma: application of the method to a bioequivalence study.

A sensitive and specific LC/MS/MS method was developed and validated for the determination of scopolamine butylbromide in human plasma. Scopolamine butylbromide and propanolol (internal standard) were extracted from the plasma by liquid-liquid extraction with dichloromethane as the extraction solvent and separated on a C18 analytical column (50 x 4.6 mm id) maintained at 40 degrees C. The analytes were eluted at a constant flow rate of 0.45 mL/min; the mobile phase consisted of acetonitrile and a buffer of 5 mM ammonium acetate and 0.1% formic acid (60 + 40, v/v). The mass spectrometer, equipped with an electrospray source in the positive ionization mode, was set up in the multiple-reaction monitoring mode to monitor the transitions m/z 360.6 > 102.5 (scopolamine butylbromide) and m/z 259.7 > 115.6 (propanolol). The chromatographic separation was obtained within 2.0 min, and the responses were linear over the concentration range of 0.10-40.00 ng/mL. The mean extraction recoveries of scopolamine butylbromide and propanolol from plasma were 69.00 and 80.76%, respectively. Method validation parameters, such as specificity, linearity, precision, accuracy, and stability, were within the acceptable range. Moreover, when the proposed method was successfully applied to a pharmacokinetic study of healthy human volunteers, the results showed that the two scopolamine butylbromide formulations tested are not bioequivalent in rate and extent of absorption.

Growth and final product formation by Bifidobacterium infantis in aerated fermentations.

Fermentation conditions were developed to allow Bifidobacterium infantis to grow in the presence of air. Batch fermentations in TPYG medium, starting from anoxic conditions followed by the application of low airflow rates [0.02-0.1 air volume, per liquid media volume, per minute (vvm)], were analyzed for growth, oxygen uptake, and product formation by the bacterium. Under all aerated fermentations, B. infantis showed high aerotolerance, with a maximum oxygen-specific consumption rate of 0.34 mmol oxygen per gram dry cell weight per hour in the presence of 0.06 vvm. Similar growth yields were obtained under oxic and anoxic conditions (0.11-0.13 and 0.11 g dry cell weight per mmol glucose, respectively). Oxygen also influenced metabolite formation since lactate production and its molar relation to acetate increased and formate decreased with aeration rate. Under anoxic conditions, a maximum concentration of 8.1 mM lactate and an acetate/lactate ratio of 3.5:1 were obtained, while under oxic conditions the lactate concentration increased more than two-fold and the acetate/lactate molar ratio decreased to 1.5:1. The possibility of balancing acetate/lactate molar ratios for organoleptic purposes as well as for obtaining good growth under microaerated conditions was demonstrated.

Mars-like soils in the Atacama Desert, Chile, and the dry limit of microbial life.

The Viking missions showed the martian soil to be lifeless and depleted in organic material and indicated the presence of one or more reactive oxidants. Here we report the presence of Mars-like soils in the extreme arid region of the Atacama Desert. Samples from this region had organic species only at trace levels and extremely low levels of culturable bacteria. Two samples from the extreme arid region were tested for DNA and none was recovered. Incubation experiments, patterned after the Viking labeled-release experiment but with separate biological and nonbiological isomers, show active decomposition of organic species in these soils by nonbiological processes.

Observations of formic and acetic acids at three sites of Mexico City.

Levels of atmospheric carboxylic acids in gas and particulate matter were measured at three sites in Mexico City within the month of March 2000. An annular denuder system was used for sampling and the analytical method was HPLC with UV detection. Formic and acetic acids were present in the PM2.5 fraction and in the gas phase. Total concentration of formic acid was between 0 and 7 ppbV and total concentration of acetic acid was between 1 and 17 ppbV. On average 53% of the formic acid and 67% of the acetic acid were present in particulate matter.

Propuesta de un nuevo modelo de historia anestésica / Proposal of an new model of history anesthesic

La anestesia ha tenido una evolución creciente apoyada por el rápido desarrollo tecnológico del cual se vale para brindar mayor seguridad al paciente. Paradójicamente, la historia anéstesica venezolana no ha tenido tal evolución. Los modelos que se siguen empleando hoy en día no han sido actualizados de acuerdo a ,los estándares nacionales e internacionales para el ejercicio de la especialidad. Se revisaron los modelos de historia de cinco centros asistenciales de Caracas, así como cinco modelos de centros internacionales. Se obtuvo un modelo final que fue revisado sucesivamente con la ayuda de un programa gráfico de computación. La intención de este artículo es ofrecer al anestesiólogo una historia anestésica que incluya no sólo parámetros de relevancia médica y legal, los cuales permiten mayor eficacia y eficiencia en el trabajo, sino también mayor seguridad adecuándose a los criterios establecidos por la Sociedad Venezolana de Anestesiología y la American Society of Anestesiology