Microbial synergies drive simultaneous biodegradation of ethoxy and alkyl chains of Nonylphenol Ethoxylate in fluidized bed reactors.

The widely-used surfactant Nonylphenol Ethoxylate (NPEO) produces endocrine-disrupting compounds during biodegradation, with these byproducts being more harmful than untreated NPEO. This study investigates the effectiveness of a Fluidized Bed Reactor (FBR) in reducing the production of 4-Nonylphenol (4-NP) during the biodegradation of NPEO. Two identical FBR filled with sand were used to assess the NPEO degradation and to enhance the microbial consortia capable of breaking down the complex byproducts, ethanol and fumarate were introduced as co-substrates. Our findings demonstrate the significant potential of the FBR, especially when coupled with fumarate, for enhancing the surfactant degradation. It outperforms the efficiency achieved with ethanol as the primary electron donor, albeit with a higher rate of byproduct production. Microbial community taxonomy and metabolic prediction revealed the high abundance of Geobacter (1.51-31.71%) and Methanobacterium (1.08-13.81%) in non-conductive sand. This may hint a new metabolic interaction and expand our understanding of Direct Interspecies Electron Transfer (DIET) in bioreactors applied to micropollutants degradation. Such an intricate relationship between facultative and anaerobes working together to simultaneously biodegrade the ethoxy and alkyl chains presents a new perspective on NPEO degradation and can potentially be extended to other micropollutants.

Bio-CH4 yield of swine manure and food waste optimized by co-substrate proportions diluted in domestic sewage and pH interactions using the response surface approach.

This research aimed at evaluating optimal conditions to obtain value-added metabolites, such as bio-CH4, by co-digesting swine manure and food waste diluted in domestic sewage. The assays were carried out in batches using the statistical methods of Rotational Central Composite Design (RCCD) and Surface Response to evaluate the ranges of food waste (1.30-9.70 gTS.L-1), pH (6.16-7.84) and granular Upflow Anaerobic Sludge Blanket sludge as inoculum (2.32-5.68 gTS.L-1), besides about 250 mL of swine manure in 500 mL Duran flasks. According to the RCCD matrix, bio-CH4 yields among 600.6 ± 60.1 and 2790.0 ± 112.0 mL CH4 gTS.L-1 were observed, besides the maximum CH4 production rate between 0.4 ± 0.5 and 49.7 ± 2.0 mL CH4 h-1 and λ between ≤0.0 and 299.3 ± 4.5 h. In the validation assay, the optimal conditions of 9.98 gTS.L-1 of food waste, pH adjusted to 8.0 and 2.20 gTS.L-1 of inoculum were considered, and the bio-CH4 yield obtained (5640.79 ± 242.98 mL CH4 gTS.L-1 or also 5201.83 ± 224.07 mL CH4 gTVS.L-1) was 11.3 times higher than in assays before optimization (499.3 ± 16.0 mL CH4 gTS.L-1) with 5 gTS.L-1 of food waste, 3 gTS.L-1 of inoculum and pH 7.0. Besides, the results observed about the energetic balance of the control and validation assays highlight the importance of process optimization, as this condition was the only one with energy supply higher than the energy required for its operation, exceeding max consumption sevenfold. Based on the most dominant microorganisms (Methanosaeta, 31.06%) and the metabolic inference of the validation assay, it could be inferred that the acetoclastic methanogenesis was the predominant pathway to CH4 production.

Application of Dispersive Liquid-Liquid Microextraction Followed by High-Performance Liquid Chromatography/Tandem Mass Spectrometry Analysis to Determine Tetrabromobisphenol A in Complex Matrices.

An accurate and sensitive ultrasound-dispersive liquid-liquid microextraction technique followed by high-performance liquid chromatography separation coupled with electrospray ionization tandem mass spectrometry detection method to determine the presence of tetrabromobisphenol A (TBBPA) in complex environmental matrices is proposed. The miniaturized procedure was used to extract and quantify the analyte in domestic sewage, anaerobic sludge, and the aquatic test organism species Daphnia magna and Chironomus sancticaroli, which are standardized organisms for ecotoxicity bioassays. Limits of detection of 2 ng L-1 (domestic sewage), 2 ng g-1 (anaerobic sludge), 0.25 ng g-1 (D. magna), and 5 ng g-1 (C. tentans) were obtained. The presence of TBBPA was determined in domestic sewage and anaerobic sludge from an anaerobic batch bioreactor at a concentration of 0.2 ± 0.03 µg L-1 and 507 ± 79 ng g-1 , respectively. In D. magna and C. sancticaroli exposed to TBBPA in an acute toxicity bioassay, the micropollutant accumulated at 3.74 and 8.87 µg g-1 , respectively. The proposed method is a simple and cost-effective tool to determine TBBPA environmental occurrence and biomagnification potential compared with conventional extraction methods. To the best of our knowledge, this is the first liquid-liquid miniaturized extraction method to be applied to D. magna and C. sancticaroli. Environ Toxicol Chem 2020;39:2147-2157. © 2020 SETAC.

Influence of organic loading rate on ciprofloxacin and sulfamethoxazole biodegradation in anaerobic fixed bed biofilm reactors.

Antibiotic compounds, notably sulfamethoxazole (SMX) and ciprofloxacin (CIP), are ubiquitous emerging contaminants (ECs), which are often found in domestic sewage. They are associated with the development of antimicrobial resistance. Operational parameters, e.g. organic loading rate (OLR), hydraulic retention time (HRT) and sludge retention time, may influence EC biodegradation in wastewater treatment plants. This study assessed the impact of the OLR variation on the biodegradation of CIP and SMX, applying two configurations of anaerobic fixed bed reactors: anaerobic packed bed biofilm reactor (APBBR) and anaerobic structured bed biofilm reactor (ASBBR). A significant reduction in the biodegradation of SMX (APBBR: 93-69%; ASBBR: 94-81%) and CIP (APBBR: 85-66%; ASBBR: 85-64%) was observed increasing OLR from 0.6 to 2.0 kgCOD m-3 d-1. The decrease in the HRT from 12 to 4 h resulted in higher liquid-phase mass transfer coefficient (APBBR: ks from 0.01 to 0.05 cm h-1; ASBBR: ks from 0.07 to 0.24 cm h-1), but this was not enough to overcome the decrease in the antibiotic-biomass contact time on biofilm, thus reducing the bioreactors' performance. The ASBBR favored biomethane production (from 7 to 17 mLCH4 g-1VSS L-1 d-1) and biodegradation kinetics (kbio from 1.7 to 4.2 and for SMX and from 2.1 to 4.8 L g-1VSS d-1 for CIP) due to the higher relative abundance of the archaea community in the biofilm and the lower liquid-phase mass transfer resistance in the structured bed. CIP and SMX cometabolic biodegradation was associated to the hydrogenotrophic methanogenesis (mainly Methanobacterium genus) in co-culture with fermentative bacteria (notably the genera Clostridium, Bacillus, Lactivibrio, Syntrophobacter and Syntrophorhabdus). The anaerobic fixed bed biofilm reactors proved to be highly efficient in biodegrading the antibiotics, preventing them from spreading to the environment.

Feasibility of anaerobic packed and structured-bed reactors for sulfamethoxazole and ciprofloxacin removal from domestic sewage.

This study assessed the applicability of fixed bed bioreactors in two configurations - anaerobic structured bed reactor (ASBR) and anaerobic packed bed reactor (APBR) - in the removal of Sulfamethoxazole (SMX) and Ciprofloxacin (CIP), two antibiotics frequently detected in sanitary sewage. The problem of these pharmaceuticals as emerging contaminants in conventional sewage treatment systems is mainly because they encourage the development and spread of resistance genes in bacteria. Both reactors had similar performances, and the antibiotics were highly removed - APBR: 85 ±â€¯10% for SMX and 81 ±â€¯16% for CIP; ASBR: 83 ±â€¯12% for SMX and 81 ±â€¯15% for CIP. The ASBR showed to be potentially more feasible in operating and economic terms compared to the APBR, as the former presents a smaller amount of support material in the bed. SMX was completely biotransformed, while the influence of the sorption mechanism was observed for CIP, as its presence was detected sorbed onto biomass throughout the reaction bed of the reactors, with a partition coefficient (log KD) of around 2.8 L·kg-1TSS. The degradation kinetics of the pharmaceuticals were fitted using a first-order kinetic model, whereby the reactors behaved as plug flow ones, indicating the possibility of optimizing the operation for a hydraulic retention time of 6 h. The removal kinetics was more favorable for CIP (higher apparent constant kinetic - kCIPapp > kSMXapp), since its biodegradation is linked to the biomass, which is more concentrated in the bed bottom layer. The experimental results showed the potential of anaerobic fixed bed reactors in removing environmentally relevant concentrations of SMX and CIP found in sewage.

Monitoring the Activity of Immobilized Lipase with Quinizarin Diester Fluoro-Chromogenic Probe.

Quinizarin diester is used as a fluoro-chromogenic substrate of the activity of lipase supported in poly(methylmetacrylate) beads (CALB, Novozym® 435) dispersed in organic solvents. The monoester and diester of quinizarin are both non-fluorescent species contrasting with the enzymatic product quinizarin that shows optical absorption in the visible region and strong fluorescence signal. The enzymatic conversion is accomplished by spectroscopic measurements and it follows a sigmoid curve from which the mean reaction time of the enzymatic process can be determined. This parameter indicates the enzyme activity of the immobilized lipase. Its dependency with the amount of lipase allowed the determination of the ratio of the catalytic rate and the Michaelis constant (kc/Km) and the experimental value found was (1.0 ± 0.1) × 10-2 mg-1/min in the case of quinizarin diacetate.

Evaluación de una estrategia de mejora sobre la incidencia de errores en la prescripción de medicamentos en una unidad de cuidados intensivos pediátricos / Evaluation of an improvement strategy on the incidence of medication prescribing errors in a pediatric intensive care unit

Los errores en la prescripción médica (EPM) son una de las causas más frecuentes de eventos adversos. Las unidades de cuidados intensivos constituyen un ámbito de alto riesgo para su aparición. Objetivos. Describir la incidencia y los tipos de EPM en nuestra Unidad de Cuidados Intensivos Pediátricos. Evaluar si la implementación de una estrategia de mejora sobre los EPM modifica su incidencia a inmediato y largo plazo. Población y métodos. Estudio tipo antes y después, no controlado, prospectivo. Universo y muestra. Todas las prescripciones médicas de los pacientes internados en la Unidad de Cuidados Intensivos Pediátricos del Hospital General de Niños Pedro de Elizalde, en los períodos julio-diciembre de 2013 y julio-agosto de 2014. Resultados. En la etapa preintervención, la tasa de EPM fue de 13,9%; el EPM más frecuente fue la falta de hora de modificación de un determinado medicamento, seguido por la omisión de dosis o medicamento. La medicación implicada con mayor frecuencia en los EPM fue el grupo de sedoanalgesia continua. Luego de la aplicación de un programa de mejora sobre EPM, la incidencia disminuyó a 6,3 errores por 100 prescripciones. El tipo de EPM en el cual se evidenció mayor reducción fue la falta de hora de modificación. A excepción del ítem plan de hidratación parenteral y electrolitos, todos los demás grupos de drogas analizados presentaron una marcada reducción. La tasa de EPM, luego de transcurrido un año del diagnóstico de situación, fue del 5,8%; mantuvo valores similares a la etapa de posintervención inmediata. Conclusión. La gestión de un programa de mejora sobre los EPM permitió un descenso en su incidencia.

Medical prescribing errors (MPEs) are one of the most common causes of adverse events. Intensive care units are a high-risk setting for their occurrence. Objectives. To describe the incidence and types of MPEs in our Pediatric Intensive Care Unit. To assess whether the implementation of an improvement strategy on MPEs affects their incidence in the short- and long-term. Population and Methods. Prospective, uncontrolled, before-after study. Universe and sample. All medical prescriptions for patients hospitalized in the Pediatric Intensive Care Unit of the Hospital General de Niños Pedro de Elizalde from July-December, 2013 and from July-August, 2014. Results. In the pre-intervention period, MPEs rate was 13.9%, the most common being the absence of the time a given medication was modified, followed by missing a dose or medication. The medication most frequently involved in MPEs was the sedation and continuous analgesia group. After the implementation of an improvement program on MPEs, the incidence decreased to 6.3 errors every 100 prescriptions. The MPE type which showed the greatest reduction was the absence of the time of modification. Except for parenteral hydration and electrolyte supplementation, the rest of the analyzed medication groups showed a marked reduction. One year after having reviewed the situation, the MPE rate was 5.8%, and values remained similar to those of the immediate postintervention period. Conclusion. Managing an improvement program on MPEs resulted in a decrease in its incidence.

Evaluación de una estrategia de mejora sobre la incidencia de errores en la prescripción de medicamentos en una unidad de cuidados intensivos pediátricos / Evaluation of an improvement strategy on the incidence of medication prescribing errors in a pediatric intensive care unit

Los errores en la prescripción médica (EPM) son una de las causas más frecuentes de eventos adversos. Las unidades de cuidados intensivos constituyen un ámbito de alto riesgo para su aparición. Objetivos. Describir la incidencia y los tipos de EPM en nuestra Unidad de Cuidados Intensivos Pediátricos. Evaluar si la implementación de una estrategia de mejora sobre los EPM modifica su incidencia a inmediato y largo plazo. Población y métodos. Estudio tipo antes y después, no controlado, prospectivo. Universo y muestra. Todas las prescripciones médicas de los pacientes internados en la Unidad de Cuidados Intensivos Pediátricos del Hospital General de Niños Pedro de Elizalde, en los períodos julio-diciembre de 2013 y julio-agosto de 2014. Resultados. En la etapa preintervención, la tasa de EPM fue de 13,9%; el EPM más frecuente fue la falta de hora de modificación de un determinado medicamento, seguido por la omisión de dosis o medicamento. La medicación implicada con mayor frecuencia en los EPM fue el grupo de sedoanalgesia continua. Luego de la aplicación de un programa de mejora sobre EPM, la incidencia disminuyó a 6,3 errores por 100 prescripciones. El tipo de EPM en el cual se evidenció mayor reducción fue la falta de hora de modificación. A excepción del ítem plan de hidratación parenteral y electrolitos, todos los demás grupos de drogas analizados presentaron una marcada reducción. La tasa de EPM, luego de transcurrido un año del diagnóstico de situación, fue del 5,8%; mantuvo valores similares a la etapa de posintervención inmediata. Conclusión. La gestión de un programa de mejora sobre los EPM permitió un descenso en su incidencia.(AU)

Medical prescribing errors (MPEs) are one of the most common causes of adverse events. Intensive care units are a high-risk setting for their occurrence. Objectives. To describe the incidence and types of MPEs in our Pediatric Intensive Care Unit. To assess whether the implementation of an improvement strategy on MPEs affects their incidence in the short- and long-term. Population and Methods. Prospective, uncontrolled, before-after study. Universe and sample. All medical prescriptions for patients hospitalized in the Pediatric Intensive Care Unit of the Hospital General de Niños Pedro de Elizalde from July-December, 2013 and from July-August, 2014. Results. In the pre-intervention period, MPEs rate was 13.9%, the most common being the absence of the time a given medication was modified, followed by missing a dose or medication. The medication most frequently involved in MPEs was the sedation and continuous analgesia group. After the implementation of an improvement program on MPEs, the incidence decreased to 6.3 errors every 100 prescriptions. The MPE type which showed the greatest reduction was the absence of the time of modification. Except for parenteral hydration and electrolyte supplementation, the rest of the analyzed medication groups showed a marked reduction. One year after having reviewed the situation, the MPE rate was 5.8%, and values remained similar to those of the immediate postintervention period. Conclusion. Managing an improvement program on MPEs resulted in a decrease in its incidence.(AU)

Evaluation of an improvement strategy on the incidence of medication prescribing errors in a pediatric intensive care unit.

UNLABELLED: Medical prescribing errors (MPEs) are one of the most common causes of adverse events. Intensive care units are a high-risk setting for their occurrence. OBJECTIVES: To describe the incidence and types of MPEs in our Pediatric Intensive Care Unit. To assess whether the implementation of an improvement strategy on MPEs affects their incidence in the short- and long-term. POPULATION AND METHODS: Prospective, uncontrolled, before-after study. Universe and sample. All medical prescriptions for patients hospitalized in the Pediatric Intensive Care Unit of the Hospital General de Niños Pedro de Elizalde from July-December, 2013 and from July-August, 2014. RESULTS: In the pre-intervention period, MPEs rate was 13.9%, the most common being the absence of the time a given medication was modified, followed by missing a dose or medication. The medication most frequently involved in MPEs was the sedation and continuous analgesia group. After the implementation of an improvement program on MPEs, the incidence decreased to 6.3 errors every 100 prescriptions. The MPE type which showed the greatest reduction was the absence of the time of modification. Except for parenteral hydration and electrolyte supplementation, the rest of the analyzed medication groups showed a marked reduction. One year after having reviewed the situation, the MPE rate was 5.8%, and values remained similar to those of the immediate postintervention period. CONCLUSION: Managing an improvement program on MPEs resulted in a decrease in its incidence.

Fluorescence modulation of acridine and coumarin dyes by silver nanoparticles.

Silver nanoparticles were synthesized by chemical reduction of silver ions by sodium borohydride in the presence of poly-(N)-vinyl-2-pyrrolidone in solution of short chain alcohols. The nanoparticles are stable in 2-propanol, and the average diameter of the Ag colloid obtained in this solvent is about 6 nm. The photophysical properties of acridinium and coumarin dyes in 2-propanol are affected by the presence of silver nanoparticles. The interaction of silver nanoparticles with acridinium derivative leads to a spectral change of its intramolecular charge transfer (ICT) absorption band. The dye emission increases suddenly with the initial addition of the Ag metal nanoparticles, but at a high concentration of the colloid, static fluorescence quenching occurs with a progressive decrease of the fluorescence efficiency. Amino coumarin fluorescence is only quenched by the silver nanoparticles in solution.