Study of a torus bioreactor for the enzymatic elimination of phenol

Phenols are priority pollutants that are commonly found in a large number of industrial wastewaters. Different processes are currently available for the elimination of phenol from wastewater but present some disadvantages like low efficiency, high energy-consumption, the necessity of acclimatisation of the sludges or the limitation of the treatment capacity. The need to find alternatives has made the enzymatic processes a good option. In the last two decades, several processes were implemented with different enzymes from plants and microorganisms, including peroxidases from several sources, as the horseradish peroxidase.Also, different enzyme configurations, free or immobilised enzyme and different supports for immobilisation have been studied. Substantial attention has been devoted to the covalent immobilisation of enzymes on porous insoluble supports such as glass, alumina, silica, and chitosan.The main novelty of this work is the utilisation of a torus reactor for the removal of organic contaminants from wastewaters. This reactor, which can be considered as a loop reactor, presents some advantages over other stirred tank reactors.The goal of this work is the study of the hydrodynamics of a torus reactor for its further application in the enzymatic elimination of phenol and the coupling of the kinetics and the modelisation.In a first step, the enzymatic elimination of phenol was experimentally studied in the torus reactor. In order to compare the performances, several assays were also carried out with a stirred reactor. A high degree of conversion was obtained for the enzymatic elimination of phenol in both reactors with the tested quantities of phenol. It was concluded that, keeping a ratio of 1:1 between the phenol and the H2O2 initial molar quantities, the highest final reaction conversion was obtained. Using the torus reactor was obtained 97% of phenol conversion when the optimal concentrations of substrates were usedIn order to improve economically the process, the enzyme should be used in a continuous regime over a long time period to exploit it completely. For this reason it was necessary to immobilise the enzyme. This work presents a new configuration that has never been tested: the horseradish peroxidase supported on Eupergit.In a second step, the characterisation using the CFD of the flow-field in a torus reactor of 100 ml, similar to the experimental reactor, was carried out for two different configurations, batch and continuous operating modes. Moreover, the scale-up of the volume of the torus reactor was carried out using CFD for a 300 ml reactor.Finally, the enzymatic reaction of phenol with the HRP was modelled using the CFD coupled to the kinetic model of the enzymatic reaction to the flow simulation. These results allowed the possibility of optimising and scaling-up the process using the CFD modelisation.Los compuestos fenólicos son contaminantes prioritarios que se encuentran comúnmente en una gran cantidad de efluentes industriales. Diferentes procesos están disponibles actualmente para la eliminación de fenol desde dicho efluentes pero los mismos presentan algunas desventajas como pueden ser una baja eficiencia, un mayor consumo de energía, la producción de lodos conteniendo hierro o limitaciones en la capacidad de tratamiento. La necesidad de encontrar alternativas a estos problemas ha hecho del proceso enzimático una buena opción. En las últimas dos décadas, varios procesos han sido implementados utilizando diferentes enzimas extraídas de plantas y microorganismos como pueden ser las peroxidasas de diversas fuentes, incluyendo la horseradish peroxidasa.Diferentes configuraciones de enzimas, libre e inmovilizada y diferentes soportes para la inmovilización han sido también estudiados. Sustancial atención ha sido dedicada a la inmovilización de enzimas por enlace covalente sobre soportes porosos insolubles tales como vidrio, aluminio, sílice y chitosan. El objetivo de este trabajo es el estudio de la hidrodinámica dentro de un reactor tórico para su posterior aplicación en la eliminación enzimática de fenol y el acople entre las cinéticas y la modelización.En una primera etapa, la eliminación enzimática de fenol es estudiada experimentalmente en el reactor tórico. Con el objetivo de comparar el rendimiento de dicho reactor, varios ensayos se realizaron en un reactor agitado tradicional. Un alto grado de conversión de fenol ha sido obtenido para la eliminación enzimática de fenol en ambos reactores para las cantidades estudiadas de fenol. Ha sido observado que es necesario mantener una relación de 1:1 entre la concentración inicial de fenol y la de peróxido de hidrógeno para lograr la mayor conversión de fenol. Usando el reactor tórico ha sido obtenido un 97% de conversión de fenol cuando las concentraciones óptimas de substratos y enzimas fueron utilizados. Con el objetivo de mejorar económicamente el proceso y hacerlo factible para su uso a escala industrial, la enzima debería ser utilizada en un proceso en continuo sobre un largo período de tiempo para explotarla completamente. Por esta razón, ha sido necesario inmovilizar la enzima. Este trabajo muestra una nueva configuración que no ha sido aún probada: la horseradish peroxidase soportada en Eupergit. Asimismo, la caracterización usando CFD del campo de flujo de un reactor tórico similar al experimental de 100 ml ha sido realizada para un reactor trabajando de forma batch y continua. Un escalado en el volumen del reactor tórico ha sido realizado utilizando CFD para un reactor de 300 ml. Finalmente, la reacción enzimática de fenol con HRP has sido modelada acoplando el modelo cinético obtenido experimentalmente con las simulaciones del campo de flujo dentro del reactor. Estos resultados permitirán la optimización y el escalado del proceso usando CFD

Use of Native Microorganisms as an Alternative for Biological Removal of Organic Matter in Wastewater from the Pharmaceutical Industry

The impact of non-domestic wastewater (nDWW) on water bodies every day is increased, considering the different pollutants that are entering and these are not regulated, also that the effects of these are not known in the ecosystems. In the case of the pharmaceutical industry, the various products they generate can contribute from non-steroidal anti-inflammatory analgesics (NSAIDs), antihypertensives, hormones, antibiotics, among others; they are being detected in surface waters and it is necessary to create strategies to improve treatment systems and thus reduce their effects on water systems. In this work, the native microorganisms from nDWW of the pharmaceutical industry were used to evaluate their ability to influence the removal of organic matter, working in mixed culture, where it was evidenced that in a 24 hours they could remove 45.82 % of the organic matter measured by the chemical oxygen demand (COD) and at 48 hours 90.59 % removal. The above shows that the use of microorganisms can contribute to the reduction of COD and pollutants in an effective, environmentally friendly and, more efficient way than conventional methods. Besides, the qualities of tolerance to four NSAIDs by 16 morphotypes are evidenced, and how they can be profiled in the future to be potentialized and reach the mineralization of these emerging pharmaceutical pollutants

Pre-treatment clinical and gene expression patterns predict developmental change in early intervention in autism.

Funder: U.S. Department of Health & Human Services | NIH | National Institute of Mental Health (NIMH)Early detection and intervention are believed to be key to facilitating better outcomes in children with autism, yet the impact of age at treatment start on the outcome is poorly understood. While clinical traits such as language ability have been shown to predict treatment outcome, whether or not and how information at the genomic level can predict treatment outcome is unknown. Leveraging a cohort of toddlers with autism who all received the same standardized intervention at a very young age and provided a blood sample, here we find that very early treatment engagement (i.e., <24 months) leads to greater gains while controlling for time in treatment. Pre-treatment clinical behavioral measures predict 21% of the variance in the rate of skill growth during early intervention. Pre-treatment blood leukocyte gene expression patterns also predict the rate of skill growth, accounting for 13% of the variance in treatment slopes. Results indicated that 295 genes can be prioritized as driving this effect. These treatment-relevant genes highly interact at the protein level, are enriched for differentially histone acetylated genes in autism postmortem cortical tissue, and are normatively highly expressed in a variety of subcortical and cortical areas important for social communication and language development. This work suggests that pre-treatment biological and clinical behavioral characteristics are important for predicting developmental change in the context of early intervention and that individualized pre-treatment biology related to histone acetylation may be key

Promising co-inoculation strategies to reduce arsenic toxicity in soybean

Arsenic (As) is cause for concern worldwide due to its high toxicity. Its presence in agricultural soils and groundwater adversely affects soybean (Glycine max L.) growth and yield, and also endangers food safety. Plant growth-promoting rhizobacteria (PGPR) could be used as part of cost-effective and eco-friendly strategies to mitigate As phytotoxicity. However, simple inoculation of soybean with PGPR Bradyrhizobium japonicum E109 (E109), a common practice in Argentina, is not effective in counteracting the effects of As exposure. Our aim was to assess whether the response of soybean to arsenate (AsV) and arsenite (AsIII) could be helpfully modulated by co-inoculating E109 with the free-living PGPRs Azospirillum brasilense Cd (Cd) or Bacillus pumilus SF5 (SF5). Co-inoculation with E109+SF5 alleviated As-induced depletion of chlorophyll a and b, and carotenoid content, reaching an increase of 26, 28 y 31%, respectively. It also enhanced nodulation (15-19%) under As exposure. E109+Cd and E109+SF5 induced changes in the antioxidant system, which could be related to the maintenance of redox homeostasis. Moreover, As accumulation was reduced by 53% in aerial parts of plants inoculated with E109+Cd, and by 16% in the roots of those inoculated with E109+SF5. The strains selected show interesting potential for the development of biotechnological schemes to improve soybean yield while guaranteeing safer food production.Fil: Vezza, Mariana Elisa. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Pramparo, Romina del Pilar. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Wevar Oller, Ana Laura. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; ArgentinaFil: Agostini, Elizabeth. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Instituto de Biotecnología Ambiental y Salud - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Biotecnología Ambiental y Salud; ArgentinaFil: Talano, Melina Andrea. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas Fisicoquímicas y Naturales. Departamento de Biología Molecular; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Performance comparison of torus and magnetically-stirred reactor for the enzymatic elimination of phenol

The goal of this work is the comparison of the performances of a torus and a stirred reactor for the enzymatic elimination of phenol. High degrees of conversion were obtained in both reactors for the three initial concentrations of phenol tested. In the case of the torus reactor, around 97%, 85% and 56% of phenol conversion were obtained for initial phenol concentrations of 0.5, 1.1 mM and 1.6 mM respectively, with the optimal concentrations of hydrogen peroxide. In the case of using the magnetically-stirred vessel, the extension of the phenol elimination was around 89%, 67% and 58% for an initial phenol concentration of 0.5 mM, 1.1 mM and 1.6 mM respectively. No significative differences were observed for both reactors, nevertheless the phenol conversion that was always higher for the torus reactor. Also, the values of the initial reaction rates were always lower in the stirred reactor, suggesting that the mixing in the torus reactor is more effective. The optimal H2O2 initial concentration to achieve the highest conversion of phenol has to be a ratio equal to 1 between the phenol and the H2O2 initial molar concentration. The excess of hydrogen peroxide in the mixture inhibited the activity of the enzyme, by the conversion of the peroxidase to inactive forms, provoking a reduction of the phenol conversion

Immobilisation of horseradish peroxidase on Eupergit®C for the enzymatic elimination of phenol

In this study, three different approaches for the covalent immobilisation of the horseradish peroxidase (HRP) onto epoxy-activated acrylic polymers (Eupergit®C) were explored for the first time, direct HRP binding to the polymers via their oxirane groups, HRP binding to the polymers via a spacer made from adipic dihydrazide, and HRP binding to hydrazido polymer surfaces through the enzyme carbohydrate moiety previously modified by periodate oxidation. The periodate-mediated covalent immobilisation of the HRP on hydrazido Eupergit®C was found to be the most effective method for the preparation of biocatalysts. In this case, amaximumvalue of the immobilised enzyme activity of 127 U/gsupport was found using an enzyme loading on the support of 35.2 mg/gsupport. The free and the immobilised HRP were used to study the elimination of phenol in two batch reactors. As expected, the activity of the immobilised enzyme was lower than the activity of the free enzyme. Around 85% of enzyme activity is lost during the immobilisation. However, the reaction using immobilised enzyme showed that it was possible to reach high degrees of phenol removal (around 50%) using about one hundredth of the enzyme used in the soluble form.Peer Reviewe

Performance comparison of torus and magnetically-stirred reactor for the enzymatic elimination of phenol

The goal of this work is the comparison of the performances of a torus and a stirred reactor for the enzymatic elimination of phenol. High degrees of conversion were obtained in both reactors for the three initial concentrations of phenol tested. In the case of the torus reactor, around 97%, 85% and 56% of phenol conversion were obtained for initial phenol concentrations of 0.5, 1.1 mM and 1.6 mM respectively, with the optimal concentrations of hydrogen peroxide. In the case of using the magnetically-stirred vessel, the extension of the phenol elimination was around 89%, 67% and 58% for an initial phenol concentration of 0.5 mM, 1.1 mM and 1.6 mM respectively. No significative differences were observed for both reactors, nevertheless the phenol conversion that was always higher for the torus reactor. Also, the values of the initial reaction rates were always lower in the stirred reactor, suggesting that the mixing in the torus reactor is more effective. The optimal H2O2 initial concentration to achieve the highest conversion of phenol has to be a ratio equal to 1 between the phenol and the H2O2 initial molar concentration. The excess of hydrogen peroxide in the mixture inhibited the activity of the enzyme, by the conversion of the peroxidase to inactive forms, provoking a reduction of the phenol conversion.Postprint (published version

Performance comparison of torus and magnetically-stirred reactor for the enzymatic elimination of phenol

The goal of this work is the comparison of the performances of a torus and a stirred reactor for the enzymatic elimination of phenol. High degrees of conversion were obtained in both reactors for the three initial concentrations of phenol tested. In the case of the torus reactor, around 97%, 85% and 56% of phenol conversion were obtained for initial phenol concentrations of 0.5, 1.1 mM and 1.6 mM respectively, with the optimal concentrations of hydrogen peroxide. In the case of using the magnetically-stirred vessel, the extension of the phenol elimination was around 89%, 67% and 58% for an initial phenol concentration of 0.5 mM, 1.1 mM and 1.6 mM respectively. No significative differences were observed for both reactors, nevertheless the phenol conversion that was always higher for the torus reactor. Also, the values of the initial reaction rates were always lower in the stirred reactor, suggesting that the mixing in the torus reactor is more effective. The optimal H2O2 initial concentration to achieve the highest conversion of phenol has to be a ratio equal to 1 between the phenol and the H2O2 initial molar concentration. The excess of hydrogen peroxide in the mixture inhibited the activity of the enzyme, by the conversion of the peroxidase to inactive forms, provoking a reduction of the phenol conversion

Immobilisation of horseradish peroxidase on Eupergit®C for the enzymatic elimination of phenol

In this study, three different approaches for the covalent immobilisation of the horseradish peroxidase (HRP) onto epoxy-activated acrylic polymers (Eupergit®C) were explored for the first time, direct HRP binding to the polymers via their oxirane groups, HRP binding to the polymers via a spacer made from adipic dihydrazide, and HRP binding to hydrazido polymer surfaces through the enzyme carbohydrate moiety previously modified by periodate oxidation. The periodate-mediated covalent immobilisation of the HRP on hydrazido Eupergit®C was found to be the most effective method for the preparation of biocatalysts. In this case, amaximumvalue of the immobilised enzyme activity of 127 U/gsupport was found using an enzyme loading on the support of 35.2 mg/gsupport. The free and the immobilised HRP were used to study the elimination of phenol in two batch reactors. As expected, the activity of the immobilised enzyme was lower than the activity of the free enzyme. Around 85% of enzyme activity is lost during the immobilisation. However, the reaction using immobilised enzyme showed that it was possible to reach high degrees of phenol removal (around 50%) using about one hundredth of the enzyme used in the soluble form.Peer Reviewe

Asociaciones bióticas de los sistemas lacustres del Cretácico Temprano de la Cuenca de San Luis, centro oeste de Argentina

Significant paleobiological data has emerged from the San Luis Basin (Early Cretaceous, Aptian-Albian in Central Argentina) during the last decades. Two units in this basin include lake paleo-environments with important fossil contents in an excellent state of preservation that could be considered as Konservat Lagerstätten deposits. The association of fossil leaves and pollen grains from the La Cantera Formation is one of the most ancient and complete angiosperm records in South America and the bryophyte association of the same unit constitutes one the most complete records of its type in Argentina. Insects from five different orders have been identified in this association, and three endemic species of aquatic insects from the La Cantera Formation have been described as belonging to the Notonectidae and Corixidae families, including the oldest member of the Anisopinae subfamily. The Pterodaustro guinazui association from the Lagarcito Formation is one of the few fossil associations recorded worldwide from which it is possible to make studies on the life history parameters of pterosaurs-like growth patterns and ontogeny. The Pleuropholid fish from the Lagarcito Formation are the only record of this group in Argentina and the second in South America. Several new species of ostracods and conchostracea have also been recorded from the same units. Despite the amount of paleontological information now available from the San Luis basin, much work remains to be done on these fossil associations and the interpretation of their depositional environments.Abundante información paleobiológica relevante ha surgido en las últimas décadas de la Cuenca de San Luis (Cretácico Temprano del centro de Argentina). Dos unidades geológicas en esta cuenca incluyen ambientes lacustres con un diverso contenido fósil y una excelente conservación que puede considerarse como depósitos de tipo Konservat Lagerstatten. La asociación de restos vegetales y granos de polen de la Formación La Cantera es uno de los registros más antiguos y completos con angiospermas en América del Sur, con la presencia de otros grupos como las briofitas en los mismos niveles, que constituyen uno de los registros más completos de su tipo en Argentina. Insectos pertenecientes a cinco órdenes diferentes fueron identificados en esta asociación, y tres especies endémicas provienen de la Formación La Cantera, de las familias Notonectidae y Corixidae, incluyendo el miembro más antiguo de la subfamilia Anisopinae. La asociación de Pterodaustro guinazui de la Formación Lagarcito es uno de los escasos registros mundiales de pterosaurios donde es posible estudiar patrones de crecimiento y ontogenia de estos arcosaurios. Los peces Pleuropholidae de la misma formación son un registro único en Argentina y el segundo de su tipo en América. Varias especies de ostrácodos y conchostracos han sido registradas en estas mismas unidades. A pesar de la cantidad de información paleontológica existente proveniente de la cuenca de San Luis, mucho trabajo queda por realizar sobre estas asociaciones fósiles así como sobre la interpretación de sus ambientes depositacionales.Fil: Arcucci, Andrea Beatriz. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas. Área de Zoología; ArgentinaFil: Pramparo, Mercedes Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Codorniú Dominguez, Laura Susana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geología; ArgentinaFil: Giordano, Paula Guillermina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geología; ArgentinaFil: Castillo Elías, Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas. Área de Zoología; ArgentinaFil: Puebla, Gabriela Griselda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Mego, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Provincia de Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales. Universidad Nacional de Cuyo. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; ArgentinaFil: Gomez, Maria Angelica. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas. Área de Zoología; ArgentinaFil: Bustos Escalona, Evelyn Luz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Bioquímica y Ciencias Biológicas. Área de Zoología; Argentin