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A gas sensor array was developed and evaluated using four high-frequency quartz crystal microbalance devices (with a 30 MHz resonant frequency in fundamental mode). The QCM devices were coated with ethyl cellulose (EC), polymethylmethacrylate (PMMA), Apiezon L (ApL), and Apiezon T (ApT) sensing films, and deposited by the ultrasonic atomization method. The objective of this research was to propose a non-invasive technique for acetone biomarker detection, which is associated with diabetes mellitus disease. The gas sensor array was exposed to methanol, ethanol, isopropanol, and acetone biomarkers in four different concentrations, corresponding to 1, 5, 10, and 15 µL, at temperature of 22 °C and relative humidity of 20%. These samples were used because human breath contains them and they are used for disease detection. Moreover, the gas sensor responses were analyzed using principal component analysis and discriminant analysis, achieving the classification of the acetone biomarker with a 100% membership percentage when its concentration varies from 327 to 4908 ppm, and its identification from methanol, ethanol, and isopropanol.

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The particular plant species found in southern Brazil, Vassobia breviflora (Solanaceae) has only a few apparent studies examining its biological effect. Thus, the aim of the present study was to determine the activity of the acetone extract fraction derived from V. breviflora. Four compounds were identified by ESI-qTOF-MS: eucalrobusone R, aplanoic acid B, pheophorbide A, and pheophytin A. In addition, 5 compounds were identified by HPLC-PDA-MS/MS: all-trans-lutein, 15-cis-lutein, all-trans-ß-carotene, 5,8-epoxy-ß-carotene, and cis-ß-carotene. Cell lines A549 (lung cancer), A375 (melanoma cancer) and HeLa (cervical cancer) were incubated with different concentrations of each studied extract using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), lactate dehydrogenase (LDH), and 2'-7'dichlorofluorescin diacetate (DCFH-DA) assays. The acetonic extract exhibited cytotoxic activity at a concentration of 0.03 mg/ml in the HeLa strain and 0.1 mg/ml in the others. In addition to increased production of reactive oxygen species (ROS). Antibacterial activity was assessed utilizing minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) in 9 ATCCs strains and 7 clinical isolates, as well as determination of biofilm production. Data demonstrated that MIC and MBC were approximately 256 mg/ml in most of the strains tested and antibiofilm effect at S. aureus, S. epidermidis, A. baumannii, and E. faecalis, concentrations below the MIC. Genotoxic activity on plasmid DNA did not produce significant elevated levels in breaks in the isolated genetic material.

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The extraction of total lipids and tocopherol compounds from Patagonian squid (Doriteuthis gahi) by-products (viscera, heads, skin, etc.), resulting from squid mantel commercialisation, was studied. An optimisation simplex-lattice design by employing low-toxicity solvents (ethanol, acetone, and ethyl acetate) was carried out taking into account their relative concentrations. The variance analysis of data showed that the quadratic model was statistically significant (p < 0.05); empirical coded equations were obtained as a function of the low-toxicity solvent ratios. The optimised lipid extraction was obtained by employing the 0.642/0.318/0.040 (ethanol/acetone/ethyl acetate) solvent ratio, respectively, leading to an 84% recovery of the total lipids extracted by the traditional procedure. In all extracting systems tested, the presence of α-, γ-, and δ-tocopherol compounds was detected, α-tocopherol being the most abundant. For α-, γ-, and δ-tocopherol compounds, the optimisation process showed that acetone extraction led to the highest concentrations in the lipid extract obtained (2736.5, 36.8, and 2.8 mg·kg-1 lipids, respectively). Taking into account the recovery yield on a by-product basis, the values obtained for the three tocopherols were included in the 88.0-97.7%, 80.0-95.0%, and 25-75% ranges, respectively, when compared to the traditional extraction. This study provides a novel and valuable possibility for α-tocopherol extraction from marine by-products.

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Metal oxide (MOx) gas sensors have attracted considerable attention from both scientific and practical standpoints. Due to their promising characteristics for detecting toxic gases and volatile organic compounds (VOCs) compared with conventional techniques, these devices are expected to play a key role in home and public security, environmental monitoring, chemical quality control, and medicine in the near future. VOCs (e.g., acetone) are blood-borne and found in exhaled human breath as a result of certain diseases or metabolic disorders. Their measurement is considered a promising tool for noninvasive medical diagnosis, for example in diabetic patients. The conventional method for the detection of acetone vapors as a potential biomarker is based on spectrometry. However, the development of MOx-type sensors has made them increasingly attractive from a medical point of view. The objectives of this review are to assess the state of the art of the main MOx-type sensors in the detection of acetone vapors to propose future perspectives and directions that should be carried out to implement this type of sensor in the field of medicine.

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In the present work, for the first time, green chemically synthesized and stabilized Co3O4 nanoparticles were employed for catalytic conversion of isopropyl alcohol to acetone by dehydrogenation of IPA. Plant extract of Rosmarinus officinalis was used as a reducing and stabilizing agent for this synthesis. The biosynthesized Co3O4 nanoparticles were annealed at 450℃ followed by their physiochemical characterizations through XRD, SEM, AFM, and FTIR. Size distribution information collected through XRD and AFM back each other, and it was found to be 6.5 nm, having the highest number of nanoparticles in this size range. While SEM confirms the self-arranging property of synthesized nanoparticles due to their magnetic nature, furthermore, the biogenic Co3O4 nanoparticles were studied for their catalytic potential to convert isopropyl alcohol to acetone with the help of a UV-Visible spectrophotometer. The highest photocatalytic conversion of 99% was obtained in time period of 48 s. For the first time ever, nanoparticles were used for 5 cycles to evaluate their recyclable nature and conversion fell from 99 to 86% and the end of the 5th cycle. Later anti-bacterial activity against 3 Gram-positive and 3 Gram-negative strains gave the highest inhibition value of 99% against Streptococcus pneumoniae at 500 µg/mL. Finally, a cytotoxicity study on synthesized nanomaterials was carried out by exposing freshly drawn human macrophages to them. It was found that even at the highest concentration of 500 µg/mL, the nanoparticles showed only 28% lysis.

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This study investigated the antibacterial potential of Euphorbia hirtawhole plant extracts, honey and conventional antibiotics and their synergistic effects against selected multidrug resistant and typed bacterial strains associated with otitis media. E. hirtawhole plant extract was purified using column chromatography technique. The antibacterial assays of extracts were done using standard microbiological procedures. Protein, sodium and potassium ion leakage of the synergistic mixtures was determined using flame-photometry. At 100 mg/ml, acetone extracts presented highest inhibition against S. aureus (NCTC 6571) with 32 ± 0.83 mm zone of inhibition. The fractional inhibitory concentration indices displayed higher synergism in combination of plant extract, honey and ciprofloxacin against P. mirabilisat 0.02 compared to drug combination synergy standard (≤ 0.5). This work revealed augmentation of ciprofloxacin potency when combined with purified E. hirta acetone extract and honey and implies their high potential in the treatment of multidrug resistant infectionof otitis media.

Este estudio investigó el potencial antibacteriano de extractos de plantas enteras de Euphorbia hirta, miel y antibióticos convencionales y sus efectos sinérgicos contra cepas bacterianas seleccionadas multirresistentes y tipificadas asociadas con la otitis media. El extracto de la planta entera de E. hirtase purificó usando la técnica de cromatografía en columna. Los ensayos antibacterianos de extractos se realizaron utilizando procedimientos microbiológicos estándar. La fuga de iones de proteínas, sodio y potasio de las mezclas sinérgicas se determinó mediante fotometría de llama. A 100 mg/ml, los extractos de acetona presentaron la mayor inhibición contra S. aureus (NCTC 6571) con una zona de inhibición de 32 ± 0,83 mm. Los índices de concentración inhibitoria fraccional mostraron un mayor sinergismo en combinación de extracto de planta, miel y ciprofloxacina contra P. mirabilisa 0,02 en comparación con el estándar de sinergia de combinación de fármacos (≤ 0,5). Este trabajo reveló un aumento de la potencia de la ciprofloxacina cuando se combina con extracto de acetona purificado de E. hirtay miel e implica sualto potencial en el tratamiento de infecciones de otitis media resistentes a múltiples fármacos.

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RESUMEN El presente estudio tiene como objetivo determinar el comportamiento de algunos indicadores bioquímicos en la orina de atletas femeninas de sable, de edad juvenil, después de una sesión de entrenamiento, entre los que se destacan el pH (reacción), la glucosa, la albúmina y uno de los tres cuerpos cetónicos (la acetona). La muestra estuvo representada por siete atletas de sable femenino, pertenecientes a La Academia provincial de esgrima, categoría juvenil, con una edad promedio de 16 años y dos de experiencia. El estadígrafo utilizado para las comparaciones fue la media. La determinación del pH, cuantitativamente en la orina, fue a través del papel del pH. La determinación de la glucosa se realizó a través del método del reactivo Benedict. La albúmina se determinó en la orina, a través del método del ácido sulfosalicílico. Y la determinación de la acetona fue mediante el método de Imbert. La motivación para la investigación se debe a la incorporación del sable femenino en la esgrima contemporánea, lo que estudia las características y rendimiento del sexo femenino en el sable, arma bien rápida y fuerte. Los resultados demuestran cómo la carga aplicada durante una sesión de entrenamiento de un microciclo seleccionado de la preparación especial provocó variaciones en la mayoría de los indicadores, demostrando la aparición de un estado de acidosis en la orina, como consecuencia del trabajo realizado. Y se constató, además, la utilidad en la determinación de la albúmina para caracterizar la intensidad de la carga física.

RESUMO O presente estudo visa determinar o comportamento de alguns indicadores bioquímicos na urina de atletas do sabre feminino, de idade juvenil, após uma sessão de treino, entre os quais se destacam o pH (reação), glicose, albumina e um dos três corpos cetónicos (acetona). A amostra foi representada por sete atletas do sabre feminino, pertencentes à academia de esgrima provincial, categoria juvenil, com uma idade média de 16 anos e dois anos de experiência. A estatística utilizada para as comparações foi a média. A determinação do pH, quantitativamente na urina, foi feita através do papel de pH. A glicose foi determinada utilizando o método do reagente de Benedict. A albumina foi determinada na urina, através do método do ácido sulfosalicílico. E a acetona foi determinada pelo método de Imbert. A motivação para a investigação deve-se à incorporação do sabre feminino na esgrima contemporânea, que estuda as características e o desempenho do sexo feminino no sabre, uma arma muito rápida e forte. Os resultados mostram como a carga aplicada durante uma sessão de treino de um microciclo selecionado da preparação especial causou variações na maioria dos indicadores, demonstrando o aparecimento de um estado de acidose na urina, como consequência do trabalho realizado. Foi também confirmada a utilidade da determinação da albumina para caracterizar a intensidade da carga física.

ABSTRACT The present study aims to determine the behavior of some biochemical indicators in the urine of female sabre athletes, of juvenile age, after a training session, among which pH (reaction), glucose, albumin and one of the three ketone bodies (acetone) stand out. The sample was represented by seven female sabre athletes, belonging to the provincial fencing academy, youth category, with an average age of 16 years and two years of experience. The statistic used for comparisons was the mean. The determination of pH, quantitatively in urine, was through pH paper. Glucose was determined by the Benedict's reagent method. Albumin was determined in urine, through the sulfosalicylic acid method. In addition, acetone was determined by Imbert's method. The motivation for the research is due to the incorporation of the female sabre in contemporary fencing, which studies the characteristics and performance of the female sex in the sabre, a very fast and strong weapon. The results show how the load applied during a training session of a selected microcycle of the special preparation caused variations in most of the indicators, demonstrating the appearance of a state of acidosis in the urine, as a consequence of the work performed. The usefulness of the determination of albumin to characterize the intensity of the physical load was also confirmed.

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This study presents a green synthesis route to silver nanoparticles (AgNPs) stabilized with cashew gum (CG) or carboxymethylated cashew gum (CCG) using microwave-assisted synthesis and evaluates their antibacterial activity. The antimicrobial activity was measured by determining the minimum inhibitory concentration (MIC) with Staphylococcus aureus and Escherichia coli. In both cases of the presence of CG and CCG, it was found that higher pH lead to more efficient conversion of silver nitrate to AgNPs with well dispersed, spherical and stable particles as well as low crystallinity. CCG-capped AgNPs were slightly smaller (137.0 and 96.3 nm) than those coated with non-modified gum (144.7 and 100.9 nm). The samples presented promising antibacterial activity, especially on Gram-negative bacteria, resulting in significant membrane damage on treated bacteria in comparison to the untreated control, observed by atomic force microscopy. Thus, a quick and efficient synthesis route was applied to produce CGAgNPs and CCGAgNPs with antimicrobial potential.

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AIMS: Exhaled breath acetone (EBA) has been described as a new biomarker of heart failure (HF) diagnosis. EBA concentration increases according to severity of HF and is associated with poor prognosis, especially in acute decompensated HF. However, there are no data on chronic HF patients. The aim is to evaluate the role of EBA for predicting cardiac and overall mortality in chronic HF patients. METHODS AND RESULTS: In GENIUS-HF cohort, chronic patients were enrolled between August 2012 and December 2014. All patients had left ventricular ejection fraction ≤ 50%, and the diagnosis was established according to Framingham criteria. After consent, patients were submitted to clinical evaluation and exhaled breath collection. EBA identification and quantitative determination were done by spectrophotometry. The clinical characteristics associated with acetone were identified. All participants were followed for 18 months to assess cardiac and overall mortality. Around 700 participants were enrolled in the current analysis. Patients were 55.4 ± 12.2 years old, 67.6% male patients, and 81% New York Heart Association I/II with left ventricular ejection fraction of 32 ± 8.6%. EBA median concentration was 0.6 (0.3-1.2) ug/L. Acetone levels increased with the number of symptoms of HF and were associated with right HF signs/symptoms and liver biochemical changes. EBA at highest quartile (EBA > 1.2ug/L) was associated with a significantly worse prognosis (log rank test, P < 0.001). Cox proportional multivariable regression model revealed that EBA > 1.20ug/L was an independent predictor of cardiac (P = 0.011) and overall (P = 0.010) mortality in our population. CONCLUSIONS: This study shows that EBA levels reflect clinical HF features, especially right HF signs/symptoms. EBA is an independent predictor of cardiac and overall mortality in chronic HF patients.

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Abstract The use of organic as nonlinear optical materials has been intensively explored in the recent years due to the ease of manipulation of the molecular structure and the synthetic flexibility regarding the change of substituent groups. In the present work, the linear and nonlinear properties of two chalcones derivatives (E)-1-(4-methylphenyl)-3-phenylprop-2-en-1-one (4MP3P) and (E)-1-(4-Nitrophenyl)-3-phenylprop-2-en-1-one (4NP3P), that differ by the substituent position at the phenyl ring, were studied in the presence of protic and aprotic solvents simulated by the Polarizable Continuum Model (PCM) at DFT/B3LYP/6-311+G(d) level. The static and dynamic (1064 nm) molecular parameters as the dipole moment, linear polarizability, first and second hyperpolarizabilities were studied as function of the solvent dielectric constant value. The geometrical behavior as the chemical bond angles, torsion angles, and partial charges distribution of the compounds were studied, including calculations of gap energies in various solvents. The obtained results revealed that the substituent change of CH3 (4MP3P) to NO2 (4NP3P) benefits the nonlinear optical properties of the compounds in the presence of the solvent media, the absolute values of the parallel first hyperpolarizability were the ones that present the greater variation.

Resumen El uso de materiales orgánicos como materiales ópticos no lineales se ha explorado intensamente en los últimos años, debido a la facilidad de manipulación de estas estructuras moleculares y la flexibilidad de síntesis en relación con el cambio de grupos sustituyentes. En el presente trabajo, las propiedades lineales y no lineales de dos derivados de chalcona (E)-1-(4-metilfenil)-3-fenilprop-2-en-1-ona (4MP3P) y (E)-1-(4-nitrofenil)-3-fenilprop-2-en-1-ona (4NP3P), los cuales difieren en la posición del sustituyente en el anillo de fenilo, se estudiaron en presencia de disolventes próticos y apróticos simulados por el Modelo Continuo Polarizable a nivel DFT/B3LYP/6-311+G(d). Además, se estudiaron parámetros moleculares estáticos y dinámicos (1064 nm) como el momento dipolar, la polarización lineal y la primera y la segunda hiperpolarización en función del valor constante dieléctrico del disolvente. El comportamiento geométrico se estudió como ángulos de enlace químico, ángulos de torsión y distribución de carga parcial de compuestos, incluidos los cálculos de energía de huecos en varios solventes. Los resultados mostraron que el cambio del sustituyente CH3 (4MP3P) a NO2 (4NP3P) beneficia las propiedades ópticas no lineales de los compuestos en presencia del medio solvente, los valores absolutos de la primera hiperpolarizabilidad paralela fueron los que presentaron la mayor variación.

Resumo O uso de materiais orgânicos como materiais ópticos não lineares tem sido intensamente explorado nos últimos anos, devido à facilidade de manipulação dessas estruturas moleculares e à flexibilidade de síntese em relação à mudança de grupos substituintes. No presente trabalho, as propriedades lineares e não lineares de dois derivados de chalconas (E)-1-(4-metilfenil)-3-fenilprop-2-en-1-ona (4MP3P) e (E)-1-(4-nitrofenil)-3-fenilprop-2-en-1-ona (4NP3P), que diferem pela posição do substituinte no anel fenil, foram estudados na presença de solventes próticos e apróticos simulados pelo Modelo Continuo Polarizável (PCM) no nível DFT/B3LYP/6-311+G(d). Os parâmetros moleculares estáticos e dinâmicos (1064 nm) como momento dipolar, polarizabilidade linear, primeira e segunda hiperpolarizabilidades foram estudados em função do valor da constante dielétrica do solvente. Estudou-se o comportamento geométrico como ângulos de ligação química, ângulos de torção e distribuição parcial de cargas dos compostos, incluindo cálculos de energias de gap em vários solventes. Os resultados obtidos revelaram que a mudança do substituinte de CH3 (4MP3P) para NO2 (4NP3P) beneficia as propriedades ópticas não lineares dos compostos na presença do meio solvente, os valores absolutos da primeira hiperpolarizabilidade paralela foram os que apresentaram a maior variação.

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Cassava (Manihot esculenta Crantz) is a tropical plant that is used as fresh food, processed food, or raw material for the preparation of flours with high nutritional value. However, cassava contains cyanogenic glycosides, such as linamarin and lotaustralin, that can trigger severe toxic effects and some neurological disorders, including motor impairment, cognitive deterioration, and symptoms that characterize tropical ataxic neuropathy and spastic epidemic paraparesis (Konzo). These alterations that are associated with the consumption of cassava or its derivatives have been reported in both humans and experimental animals. The present review discusses and integrates preclinical and clinical evidence that indicates the toxic and neurological effects of cassava and its derivatives by affecting metabolic processes and the central nervous system. An exhaustive review of the literature was performed using specialized databases that focused on the toxic and neurological effects of the consumption of cassava and its derivatives. We sought to provide structured information that will contribute to understanding the undesirable effects of some foods and preventing health problems in vulnerable populations who consume these vegetables. Cassava contains cyanogenic glycosides that contribute to the development of neurological disorders when they are ingested inappropriately or for prolonged periods of time. Such high consumption can affect neurochemical and neurophysiological processes in particular brain structures and affect peripheral metabolic processes that impact wellness. Although some vegetables have high nutritional value and ameliorate food deficits in vulnerable populations, they can also predispose individuals to the development of neurological diseases.

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Background: Fuels and chemicals from renewable feedstocks have a growing demand, and acetone, butanol and ethanol (ABE) are some relevant examples. These molecules can be produced by the bacterial fermentation process using hydrolysates generated from lignocellulosic biomass as sugarcane bagasse, one of the most abundant sources of lignocellulosic biomass in Brazil. It originates as a residue in mills and distilleries in the production of sugar and ethanol. Results: In the present work, two strategies to generate hydrolysates of sugarcane bagasse were adopted. The fermentation of the first hydrolysate by Clostridium acetobutylicum DSM 6228 resulted in final concentrations of butanol, acetone and ethanol of 6.4, 4.5 and 0.6 g/L, respectively. On the other hand, the second hydrolysate presented better results (averages of 9.1, 5.5 and 0.8 g/L, respectively), even without the need for nutrient supplementation, since key elements were already present in the medium. The productivity (QP) and yield (YP/S) of the solvents with second hydrolysate were 0.5 g/L•h-1 and 0.4 g/g, respectively. Conclusions: The results described herein open new perspectives for the production of important molecules from residual lignocellulosic biomass for the fuel and chemical industries within the context of second-generation biorefinery.

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Methods for nanoparticles preparation often employ organic solvents in order to solubilize the non-polar constituents of the final nanostructures. In the research process, nanoparticles are assayed as aqueous suspensions in several cases, so that an excessive residual concentration of the organic solvent needs to be avoided since may lead to undesired secondary effects during biological tests. Despite the importance, residual solvent concentration is rarely determined, making necessary the development of quantification methods suitable for this purpose. Acetone is frequently used in drug delivery systems preparation, being capable to exert significant toxicities both, in vitro and in vivo. Thus, a simple and inexpensive UV-Vis spectrophotometric method is proposed to directly determine acetone from nanoparticles suspensions employing its reaction with vanillin. Central composite designs were employed to correct and optimize the quantification method, which was then validated according to international guidelines. The optimized method resulted accurate, precise, and linear in the range of 10-50 µg/mL, with an R2 of 0.998 and limits of detection and quantification of 2.6 and 7.8 µg/mL, respectively. The effect of several surfactants employed during nanoparticles preparation was not detrimental to the method. The proposed procedure can be successfully applied to directly quantify acetone from nanoparticles suspensions.

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The natural alkaloid epiisopiloturine has recently become the focus of study for various medicinal properties, particularly for its anti-inflammatory and antischistosomal effect. The incorporation of active molecules in natural polymeric matrices has garnered increasing interest during recent decades. A new derivative of cashew gum successfully obtained by gum acetylation has shown great potential as a carrier in controlled drug release systems. In this work, epiisopiloturine was encapsulated in acetylated cashew gum nanoparticles in order to increase solubility and allow slow release, whereas the morphology results were supported by computer simulations. The particles were produced under a variety of conditions, and thoroughly characterized using light scattering and microscopic techniques. The particles were spherical and highly stable in solution, and showed drug incorporation at high levels, up to 55% efficiency. Using a dialysis-based in vitro assay, these particles were shown to release the drug via a Fickian diffusion mechanism, leading to gradual drug release over approximately 6 h. These nanoparticles show potential for the use as drug delivery system, while studies on their potential anti-inflammatory action, as well as toxicity and efficacy assays would need to be performed in the future to confirm their suitability as drug delivery candidates.

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The parameters half-life, z value, enthalpy, entropy, and free energy were evaluated in the temperature range of 40 to 55°C for a Bacillus sp. P45 protease present in a medium composed of ionic liquid (IL) and organic solvent. The protease was previously treated in IL [Emim][Tf2 N] and increased activity was observed in four out of five organic solvents tested. The reaction medium containing acetone and IL (1:1 v/v ratio) was more stable than the buffer medium, with half-life of 2.4 h at 55°C. Thermodynamic parameters values showed there was probably less rupture of non-covalent bonds that stabilize the protein structure, which promoted the protease P45 stabilization. According to this study it was concluded that the protease P45 in a medium composed of [Emim][Tf2 N] and acetone may be used at higher temperatures than those employed in buffer or medium containing organic solvent. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 2018 © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:1102-1108, 2018.

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Grape, orange, peach and passion fruit nectars were formulated and adulterated by dilution with syrup, apple and cashew juices at 10 levels for each adulterant. Attenuated total reflectance Fourier transform mid infrared (ATR-FTIR) spectra were obtained. Partial least squares (PLS) multivariate calibration models allied to different variable selection methods, such as interval partial least squares (iPLS), ordered predictors selection (OPS) and genetic algorithm (GA), were used to quantify the main fruits. PLS improved by iPLS-OPS variable selection showed the highest predictive capacity to quantify the main fruit contents. The selected variables in the final models varied from 72 to 100; the root mean square errors of prediction were estimated from 0.5 to 2.6%; the correlation coefficients of prediction ranged from 0.948 to 0.990; and, the mean relative errors of prediction varied from 3.0 to 6.7%. All of the developed models were validated.

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Booster biocides have been widely applied to ships and other submerged structures. These compounds can be released into the marine environment as the result of vessel hull leaching and may remain in different environmental compartments. This study aimed at introducing an environmentally friendly procedure for the extraction of irgarol and diuron from fish samples by vortex-assisted matrix solid phase dispersion (VA-MSPD) with detection by liquid chromatography tandem mass spectrometry. Different types of solid supports and solvents were evaluated. The best results were found when 0.5g mussel shell, 0.5g sodium sulfate and 5mL ethanol were used. Analytical recoveries ranged from 81 to 110%, with RSD below 10%, whereas the matrix effect was between -17 and 1% (for all samples under study). LOQ values of irgarol and diuron were 5 and 50ngg-1, respectively. The method under investigation proved to be a promising alternative to controlling contamination of fish by booster biocides, with low consumption of biodegradable reagents.

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Abstract Major progress occurred in understanding inborn errors of ketone body transport and metabolism between the International Congresses on Inborn Errors of Metabolism in Barcelona (2013) and Rio de Janeiro (2017). These conditions impair either ketogenesis (presenting as episodes of hypoketotic hypoglycemia) or ketolysis (presenting as ketoacidotic episodes); for both groups, immediate intravenous glucose administration is the most critical and (mHGGCS, HMGCS2) effective treatment measure. Ketogenesis Deficiencies: New biomarkers were described for mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase (mHGGCS, HMGCS2) deficiency. New patient series refined clinical knowledge of 3-hydroxy-3-methylglutaryl-CoA lyase (HGGCL, HMGCL) deficiency. Although affected humans have not been described, two animal model phenotypes are pertinent: zebrafish deficient in monocarboxylate transporter 7 (MCT7, slc16a6) (decreased ketone body exit from hepatocytes) or mice lacking D-3-hydroxy-n-butyrate dehydrogenase (BDH1, BDH1) (isolated hyperacetoacetatemia; fatty liver). Ketolysis Deficiencies: Monocarboxylate transporter 1 (MCT1, SLC16A1) deficiency is a newly described defect of ketone body transport, joining deficiencies of succinyl-CoA:3-oxoacid CoA transferase (SCOT, OXCT1) and methylacetoacetyl-CoA thiolase (MAT, ACAT1). Some heterozygotes for MCT1 or SCOT deficiency develop ketoacidosis.

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Acetone is an important solvent and widely used in the synthesis of drugs and polymers. Currently, acetone is mainly generated by the Cumene Process, which employs benzene and propylene as fossil raw materials. Phenol is a co-product of this synthesis. However, this ketone can be generated from ethanol (a renewable feedstock) in one-step. The aim of this work is to describe the influence of physical-chemical properties of three different catalysts on each step of this reaction. Furthermore, contribute to improve the description of the mechanism of this synthesis. The acetone synthesis from ethanol was studied employing Cu/ZnO/Al2O3, Ce0.75Zr0.25O2 and ZrO2. It was verified that the acidity of the catalysts needs fine-tuning in order to promote the oxygenate species adsorption and avoid the dehydration of ethanol. The higher the reducibility and the H2O dissociation activity of the catalysts are, the higher the selectivity to acetone is. In relation to the oxides, these properties are associated with the presence of O vacancies. The H2 generation, which occurs during the TPSR, indicates the redox character of this synthesis. The main steps of the acetone synthesis from ethanol are the generation of acetaldehyde, the oxidation of this aldehyde to acetate species (which reduces the catalyst), the H2O dissociation, the oxidation of the catalyst producing H2, and, finally, the ketonization reaction. These pieces of information will support the development of active catalysts for not only the acetone synthesis from ethanol, but also the isobutene and propylene syntheses in which this ketone is an intermediate. Graphical abstract Acetone from ethanol.

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Chemical modifications to cashew gum (CG) structure have been previously reported to obtain new physicochemical characteristics, however until now there were no reports of modifications by introduction of new functional groups to add cationic character. This study presents a quaternization route for CG using a quaternary ammonium reagent. The chemical features of the quaternized cashew gum derivatives (QCG) were analyzed by: FTIR, elemental analysis, degree of substitution, Zeta potential, 1H NMR and 1H-13C correlation (HSQC). QCG were evaluated for their anti-staphylococcal activity by determining minimum inhibitory and bactericidal concentrations against pathogenic Staphylococcus spp. and by imaging using atomic force microscopy. Moreover, the mammalian cell biocompatibility were also assessed through hemolytic and cell toxicity assays. QCG presented promising antimicrobial activity against methicillin-resistant S. aureus and biocompatibility on tested cells. These results show that QCG could be a promising tool in the development of biomaterials with an anti-septic action.

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