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Cheese whey (CW), by-product of cheese production, has potential as a valuable resource due to its nutritional composition. Although options for CW degradation have been explored, a biological treatment with black soldier fly larvae (BSFL) has not been reported. This study evaluated the growth and composition of BSFL in four experimental diets with CW under different conditions. Results show that the use of CW allows larval development and weight gain, also, the conversion into larval biomass was up to 0.215. Diets ED3 (fresh CW, 38 °C) and ED4 (fresh CW, room temperature) allowed higher weight accumulation (final weight up to 0.285 g); the highest fat accumulation (12 % higher than control) was observed in ED3 (up to 45.57 %), which had less protein. Moreover, higher amounts of saturated fatty acids are generated. This study highlights the importance of an appropriate pretreatment designed for a specific waste to control desired by-products.

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The objective of this work was to develop a polymeric structure for a biofiltration unit of domestic effluents through microbiological immobilization, capable of promoting the efficient removal of pollutants, meeting local/national Brazilian standards and/or legislation while providing low environmental impact on their production. Four different structures were tested, namely, polypropylene casings without filling material (TF1); polypropylene casings filled with expanded polystyrene grains (TF2); polypropylene casings, filled with polyurethane foam (TF3); and polypropylene casings, filled with polyvinyl chloride pellets (TF4). A flow of 0.216 m3 d-1 was applied to the system, and the biofilters operated in sequential batches with a hydraulic retention time of 6 h. The efficiency potential of the four immobilization structures was verified regarding biochemical and chemical oxygen demand, total ammoniacal nitrogen and total phosphorus. Microbiological analysis of the formed biofilm, performed with the 16S library sequencing method, with amplification of the 16S rRNA V3 and V3-V4 genomic regions, showed a high diversity of microbiological colonization in the four immobilization structures, with better results and consequently greater community stability in TF2. It is recommended using the filter bed made up of unfilled casings, followed by the one filled with expanded polystyrene grains.

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Background: Management of severe eosinophilic asthma includes typing to identify allergic, eosinophilic and non-HT2 phenotypes. Elevated eosinophil levels are associated with higher IL-5 levels. Eosinophils during their migration to target tissues secrete proteins that damage the activated bronchial epithelium and correlate with asthma severity. Mepolizumab, a humanized monoclonal antibody that binds and neutralizes IL-5. Objectives: To describe experience with the use of biological anti interleukin 5 Mepolizumab. Methods: Case report, descriptive study. We included patients with severe uncontrolled asthma, a history of rhinosinusitis with nasal polyposis and/or EREA. Eosinophils 150 cells/µL, FeNO 25 ppb and spirometry with obstructive pattern. Results: 6 women with a diagnosis of severe asthma were included. Initial eosinophil values of 180 - 630 cél/µL, IgE 176 - 2500 Ui/ml, FENO 23 -39, ACT at 2, 4 and 6 months of use, minimum of 9 and maximum end of 25. Significant improvement in the ACT test from the first two months of use, decreased inhaled steroid and 0 to 2 exacerbations in 6 months. Conclusions: There are multiple studies, there are no statistically significant reports to demonstrate superiority with the use of a specific biological, together with the different economic limitations that exist in the country. It is necessary to identify target populations with phenotypes In Mexico there are few hospitals with these therapies, it is necessary to continue with the constant evaluation and contribution of information to find the right treatment for the Mexican population. that will respond to a specific therapy and direct treatment.

Antecedentes: El manejo del asma grave eosinofílica incluye tipificación para identificar fenotipos alérgicos, eosinofílicos y no TH2. Niveles elevados de eosi- nófilos se asocia a mayor nivel de IL-5. Los eosinófilos durante su migración a los tejidos diana, secretan proteínas que dañan el epitelio bronquial activado y se correlacionan con la gravedad del asma. Mepolizumab, anticuerpo monoclonal humanizado que se une y neutraliza la IL-5. Métodos: Describir experiencia con el uso de biológico anti-interleucina 5 Mepolizumab. Objetivos: Reporte de casos, estudio descriptivo. Se incluyeron pacientes con asma grave descontrolada, antecedente de Rinosinusitis con poliposis nasal y/o EREA. Eosinófilos ≥150 células/µL, FeNO ≥25 ppb y espirometría con patrón obstructivo. Resultados: Se incluyeron 6 pacientes mujeres con diagnóstico de Asma grave. Valores iniciales de eosinófilos de 180 ­ 630 cél/µL, IgE 176 ­ 2500 Ui/ml, FENO 23 -39, ACT a los 2, 4 y 6 meses de uso, mínima de 9 y final máxima de 25. Mejoría considerable en la prueba ACT desde los primeros dos meses de uso, dismi- nucion de esteroide inhalado y 0 a 2 exacerbaciones en 6 meses. Conclusiones: Existen múltiples estudios, no se cuenta con reportes estadísticamente significativos para demostrar superioridad con el uso de algún biológico en específico, aunado a las diferentes limitantes económicas que existen en el país. Es necesario identificar poblaciones objetivo con los fenotipos que responderán a una terapia específica y dirigir el tratamiento. En México hay pocos centros hospitalarios con estas terapias, es necesario continuar con la evaluación constante y aporte de información para poder encontrar el tratamiento idóneo para la población mexicana.

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During the COVID-19 pandemic, wastewater from WWTPs became an interesting source of epidemiological surveillance. However, there is uncertainty about the influence of treatment type on virus removal. The aim of this study was to assess viral surveillance within wastewater treatment plants (WWTPs) based on different biological treatments. Seasonal monitoring (autumn-winter and spring-summer) was conducted in 10 Chilean rural WWTPs, which were based on activated sludge, aerated lagoons, bio-discs, constructed wetlands, vermifilters and mixed systems. Viruses were measured (influent/effluent) by the RT-qPCR technique, using a commercial kit for SARS-CoV-2, NoV GI, NoV GII, and HAV. The detection of SARS-CoV-2 viral variants by genotyping was performed using SARS-CoV-2 Mutation Assays (ThermoFisher Scientific, USA). JC polyomavirus detection (control), as well as a qPCR technique. Results showed that SARS-CoV-2, NoV GI and GII were detected in influents at values between <5 and 462, 0 to 28, and 0 to 75 GC/mL, respectively. HAV was not detected among the studied WWTPs. The monitored WWTPs removed these viruses at percentages between 0 and 100 %. WWTPs based on activated sludge with bio-discs demonstrated to be the most efficient at removing SARS-CoV-2 (up to 98 %) and NoV GI and GII (100 %). Meanwhile, bio-discs technologies were the least efficient for viral removal, due to biofilm detachment, which could also adsorb viral aggregates. A correlation analysis established that solids, pH, and temperature are the most influential parameters in viral removal. Wastewater-based surveillance at WWTP allowed for the detection of Omicron before the Chilean health authorities notified its presence in the population. In addition, surveillance of viruses and other microorganisms could help assess the potential public health risk of wastewater recycling.

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Phenol is a noteworthy pollutant, found in effluents of many industrial processes, like oil refining and drugs production, which can impair the treatment efficiency of bioreactors. This study evaluated the performance of phenol, COD, and nitrogen removal of an aerobic bench-scale Moving Bed Biofilm Reactor (MBBR) exposed to gradually increasing phenol content over 233 days. The reactor had Hydraulic Retention Time (HRT) set at 3 h and 40% filling degree (K1 media), and was fed with synthetic wastewater containing phenol (10, 20, 50, 100, 250 and 400 mg/L), glucose (400 mgCOD/L), and 40 mgN-NH3/L. Phenol, COD, and ammoniacal nitrogen removal averages were high - above 88%, 81%, and 82%, respectively -, even when the MBBR was exposed to the greatest phenol loads, indicating that the biofilm was able to acclimate and resist high phenol concentrations. However, the intense EPS production revealed the impact caused by phenol to the biofilm from the concentration of 250 mg/L onwards. Even though, at this concentration, the average removals of COD and phenol were 87.2% and 89.7%. The removal of ammoniacal nitrogen by nitrification was compromised, being 91.6% of the ammoniacal nitrogen removed by assimilation and only 0.35% removed by nitrification. At 400 mg phenol/L, the reactor provided COD and phenol average removals equal 88.6% and 80.9%, respectively. On the last day of operation, the removal of COD dropped to 55.4% and phenol removal was equal 49.0%. Novel microscopical evaluation of the MBBR's biofilm revealed some negative effects of the phenol on the microbiota composition.

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In the industrial production of the explosive 2,4,6-trinitrotoluene (TNT), purification steps are required to ensure the quality of the product, procedures that generate wastewater of a complex nature and with eco-toxicological potential, called red water, which consists of soluble sulfonates, TNT isomers, and other typical nitro aromatic compounds. The present work aimed to study the effects of integrating heterogeneous photocatalysis based on commercial TiO2, with a biological process, based on activated sludge, for red water treatment. For the photocatalytic treatment, a 72% reduction in the typical absorption of nitro aromatic compounds (the region between 195 - 275 nm), a 36% reduction in chemical oxygen demand (COD), and a 68% reduction in total phenols were obtained. In the biological treatment, there was a 60% reduction in absorbance in the typical nitro aromatics region (NA), 10% reduction in COD, and 36% reduction in total phenols (FT). The integration of photocatalytic and biological treatments showed promising results compared to the individual processes. Having 94% reduction in NA absorbance, 72% reduction in FT, and 89% reduction in COD with an association of photocatalytic pretreatment followed by biological, and reductions of 88% in NA absorbance, 62% in FT, and 87% in COD for a biological pretreatment followed by the photocatalytic process. In general, when comparing the chemical and biological processes, isolated and integrated, both types of integration showed significantly superior results. They were able to remove the main nitro aromatic constituents of the Red Water effluent.

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Landfill leachates are high-strength complex mixtures containing dissolved organic matter, ammonia, heavy metals, and sulfur species, among others. The problem of leachate treatment has subsisted for some time, but an efficient and cost-effective universal solution capable of ensuring environmental resources protection has not been found. Aerobic granular sludge (AGS) has been considered a promising technology for biological wastewater treatment in recent years. Granules' layered structure, with an aerobic outer layer and an anaerobic/anoxic core, enables the presence of diverse microbial populations without the need for support media, allowing simultaneous removal of different pollutants in a single unit. Besides, its strong and compact arrangement provides higher tolerance to toxic pollutants and the ability to withstand large load fluctuations. Furthermore, its good that settling properties allow high biomass retention and better sludge separation. Nevertheless, AGS-related research has focused on carbon-nitrogen-phosphorus removal, mainly from sanitary sewage. This review aims to summarize and analyze the main findings and problems reported in the literature regarding AGS application to landfill leachate treatment and identify the knowledge gaps for future applications.

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A asma é o produto de processos coordenados, interligados e complexos que têm origem nos genes/epigenética, microbioma e ambiente/estilo de vida. Os medicamentos atualmente disponíveis não são capazes de interferir com a inserção da asma no organismo. A abordagem terapêutica atual envolve fármacos que visam controlar os sintomas e antagonizar parte dos efeitos de algumas das citocinas envolvidas. Dessa forma, o tratamento atual visa o controle da asma e não a sua cura. Mecanismos epigenéticos traduzem os estímulos microbiômicos e ambientais em comportamento celular alterado. Por essa razão, a identificação de marcadores epigenéticos certamente apontará novos alvos terapêuticos e, idealmente, estratégias para reverter o comportamento celular alterado no trato respiratório. Aí, sim, poderíamos dizer que a asma tem cura.

Asthma is the product of coordinated, interconnected and complex processes that originate in genes/epigenetics, microbiome, and environment/lifestyle. Currently available drugs are not able to interfere with the insertion of asthma into the body. The current therapeutic approach involves drugs that aim to control symptoms and antagonize part of the effects of some of the cytokines involved. Thus, the current treatment is aimed at controlling asthma and not curing it. Epigenetic mechanisms translate the microbiological and environmental stimuli into altered cellular behavior. For this reason, the identification of epigenetic markers will certainly point out to new therapeutic targets and, ideally, strategies to reverse the altered cellular behavior in the respiratory tract. Then, yes, we could say that asthma is curable.

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ABSTRACT One of the major drawbacks of this final disposal technique is leachate production, which occurs due to the degradation of organic matter and rainwater percolation. The leachate composition is quite varied, with high organic load and various compounds that may be toxic to the environment. To reduce the polluting potential of the leachate, it must be subjected to an appropriate treatment. Biological treatments are widely used in the treatment of leachate, although these technologies have some drawbacks. As an alternative to conventional biological treatments, rotating biological reactors are used. The objective of this study was to determine the efficiency of a pilot scale rotating biological reactors in the removal of biochemical oxygen demand, chemical oxygen demand, and phosphorus from the landfill leachate. Effluent toxicity and rotating biological reactors's ability to remove this toxicity were also verified by calculating the germination index of lettuce (Lactuca sativa) and cucumber (Cucumis sativus) seeds. The reactor showed an average efficiency of 75.99% of biochemical oxygen demand removal, 33.53% of chemical oxygen demand removal, and 16.04% of phosphorus removal. In fact, the cucumber and lettuce seeds proved sensitive to the toxicity of the effluent. For crude leachate, the germination index values of lettuce and cucumber were 13.28 and 49.61%, respectively. In this study, rotating biological reactors obtained a good efficiency in the removal of toxicity from leachate. The germination index of the seeds for the treated effluent was 60.9% for lettuce and 82.49% for cucumber.

RESUMO Diante do crescimento populacional acelerado e do desenvolvimento econômico, grande quantidade de resíduos tem sido gerada nos grandes centros urbanos. Esses resíduos devem ser coletados e dispostos adequadamente, sendo os aterros sanitários os locais mais adequados para a sua disposição. Um dos grandes inconvenientes dessa técnica de disposição final é a produção de um líquido lixiviado, proveniente da degradação da matéria orgânica e da percolação da água da chuva. A composição do lixiviado é bastante variada, com elevada carga orgânica e diversos compostos que podem ser tóxicos ao meio ambiente. Para determinar a toxicidade do lixiviado são amplamente utilizados testes fitotoxicológicos, como o índice de germinação de sementes. Com o intuito de reduzir o potencial poluidor do lixiviado, este deve ser submetido a um tratamento adequado. Tratamentos biológicos são bastante utilizados, mas possuem algumas desvantagens. Como alternativa aos tratamentos biológicos convencionais, surgem os reatores biológicos rotatórios. O objetivo deste estudo foi determinar a eficiência de uns reatores biológicos rotatórios em escala piloto na remoção da demanda bioquímica de oxigênio, da demanda química de oxigênio e de fósforo do lixiviado do aterro. Também foi verificada a toxicidade do efluente e a capacidade dos reatores biológicos rotatórios para remover essa toxicidade por meio do cálculo do índice de germinação de sementes de alface (Lactuca sativa) e pepino (Cucumissativus). O reator utilizado neste trabalho obteve eficiência média de 75,99% de remoção de demanda bioquímica de oxigênio, 33,53% de remoção de demanda química de oxigênio e 16,04% de remoção de fósforo. As sementes de alface e pepino mostraram-se bastantes sensíveis à toxicidade do efluente. Para o lixiviado bruto, os índices de germinação da alface e do pepino foram, respectivamente, 13,28 e 49,61%. Neste estudo, os reatores biológicos rotatórios obtiveram boa eficiência na remoção da toxicidade do lixiviado. O índice de germinação das sementes para o efluente tratado foi de 60,9% para a alface e de 82,49% para o pepino.

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The digestion efficiency of liquid industrial wastes increases when using bioreactors colonized by microbial biofilms. High concentrations of proteins derived from the fish processing industry lead to the production of ammonia, which inhibits methane production. Two bioreactors were constructed to compare methanogenic activity: one enriched with mMPA (methylaminotrofic methane production archaea) consortia (control bioreactor), and the second with NH3 tolerant consortia (treatment bioreactor). Ammonia tolerant activity was assessed by applying an ammonia shock (755 mg NH3/L). Methane production, consumption of total organic carbon (TOC) and the taxonomic composition of bacteria and archaea was evaluated using 16S rDNA in the acclimatization, ammonia shock, and recovery phases.The ammonia shock significantly affected both methane production and the consumption of TOC in the control reactor (p < 0.05) and taxonomical composition of the microbial consortia (OTU). These values remained constant in the treatment reactor. The analysis of biofilm composition showed a predominance of Methanosarcinaceae (Methanomethylovorans sp., and probably two different species of Methanosarcina sp.) in bioreactors. These results demonstrate that using acclimated biofilms enriched with ammonia tolerant methanogens control the inhibitory effect of ammonia on methanogenesis.

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Perchlorate is a persistent pollutant, generated via natural and anthropogenic processes, that possesses a high potential for endocrine disruption in humans and biota. It inhibits iodine fixation, a major reason for eliminating this pollutant from ecosystems. Remediation of perchlorate can be achieved with various physicochemical treatments, especially at low concentrations. However, microbiological approaches using microorganisms, such as those from the genera Dechloromonas, Serratia, Propionivibrio, Wolinella, and Azospirillum, are promising when perchlorate pollution is extensive. Perchlorate-reducing bacteria, isolated from harsh environments, for example saline soils, mine sediments, thermal waters, wastewater treatment plants, underground gas storage facilities, and remote areas, including the Antarctica, can provide removal yields from 20 to 100%. Perchlorate reduction, carried out by a series of enzymes, such as perchlorate reductase and superoxide chlorite, depends on pH, temperature, salt concentration, metabolic inhibitors, nutritional conditions, time of contact, and cellular concentration. Microbial degradation is cost-effective, simple to implement, and environmentally friendly, rendering it a viable method for alleviating perchlorate pollution in the environment.

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The history of colour is fascinating from a social and artistic viewpoint because it shows the way; use; and importance acquired. The use of colours date back to the Stone Age (the first news of cave paintings); colour has contributed to the social and symbolic development of civilizations. Colour has been associated with hierarchy; power and leadership in some of them. The advent of synthetic dyes has revolutionized the colour industry; and due to their low cost; their use has spread to different industrial sectors. Although the percentage of coloured wastewater discharged by the textile; food; pharmaceutical; cosmetic; and paper industries; among other productive areas; are unknown; the toxic effect and ecological implications of this discharged into water bodies are harmful. This review briefly shows the social and artistic history surrounding the discovery and use of natural and synthetic dyes. We summarise the environmental impact caused by the discharge of untreated or poorly treated coloured wastewater to water bodies; which has led to physical; chemical and biological treatments to reduce the colour units so as important physicochemical parameters. We also focus on laccase utility (EC 1.10.3.2), for discolouration enzymatic treatment of coloured wastewater, before its discharge into water bodies. Laccases (p-diphenol: oxidoreductase dioxide) are multicopper oxidoreductase enzymes widely distributed in plants, insects, bacteria, and fungi. Fungal laccases have employed for wastewater colour removal due to their high redox potential. This review includes an analysis of the stability of laccases, the factors that influence production at high scales to achieve discolouration of high volumes of contaminated wastewater, the biotechnological impact of laccases, and the degradation routes that some dyes may follow when using the laccase for colour removal.

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Leachate generation contains a variety of toxic compounds, and is a major problem for municipal solid waste (MSW). Microbial profile knowledge is essential to new alternatives and improvements in current treatments of these effluents. In this respect, the microbial community in the leachate from the sanitary landfill of the city of Foz do Iguaçu was analyzed. The 16S rDNA metabarcoding suggested the dominance of fermenting bacteria belonging to Firmicutes phylum, followed by Proteobacteria, Bacteroidetes, and Synergistetes. The most abundant genera were Sedimentibacter, Vulcanibacillus, and Anaerovorax. However, 60% of amplicon sequence variants (ASVs) were not classified taxonomically. In addition, an expressive abundance was attributed to the superphylum known as PVC group, little studied and with unknown scientific potential. The leachate acidogenic phase was masked in the chemical and physical analyzes. Nevertheless, it was evidenced in the metabarcoding methodology. No specifically methanogenic group was detected in significant abundance. Therefore, from bacterial community identification, a bioremediation process can be designed. Enriched culture media can be developed and targeted to the recovery of specific groups which may be involved in leachate biodegradation. What is more, the results expand the knowledge of bacterial diversity, especially from the presence of unknown genera in this habitat.

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BACKGROUND: Asthma continues to be one of the most frequent chronic respiratory diseases in our country. New methods for diagnosis and treatment have been described; accordingly, the international guidelines were renewed. OBJECTIVE: To create a national platform for the development of updated guidelines, solidly based on evidence: Comprehensive Asthma Management (Spanish acronym: MIA). METHODS: MIA uses the ADAPTE method. The MIA development group consists of experts in pulmonology-allergology-methodology and representatives of 13 institutions and societies of specialties that manage asthma. The international reference guidelines (selected with AGREE-II): GINA 2020, GEMA 5.0, BTS/SIGN 2019 and ATS/ERS consensus document 2014-2019 on severe asthma. MIA covers suspected asthma, diagnosis, treatment, and special groups. Key clinical questions were formulated on treatment steps 1-3, biomarkers and severe asthma. RESULTS: Based on evidence, safety, cost and local reality, the core group developed responses. Through a Delphi process the broad MIA development group suggested adjustments until consensus was reached. CONCLUSION: A document was generated with multiple figures and algorithms, solidly based on evidence about asthma management, adjusted for Mexico with a broad base among different societies that participated in its development. It does not include guidelines for acute asthma.

Antecedentes: El asma sigue siendo una patología respiratoria crónica frecuente en México. Se han descrito nuevos métodos para el diagnóstico y tratamiento conforme se renuevan las guías internacionales. Objetivo: Crear la plataforma nacional Manejo Integral del Asma (MIA), para el desarrollo de lineamientos actualizados con base en evidencia. Métodos: Se utilizó el método ADAPTE. El grupo de desarrollo de MIA estuvo integrado por expertos en neumología, alergología y metodología y representantes de 13 instituciones y sociedades de especialidades que manejan asma. Las guías internacionales de referencia (seleccionadas con AGREE-II) fueron GINA 2020, GEMA 5.0, BTS/SIGN 2019 y consenso ATS/ERS 2014-2019. En MIA se aborda sospecha de asma, diagnóstico, tratamiento y grupos especiales. Se formularon preguntas clínicas clave sobre tratamiento en los pasos 1 a 3, biomarcadores y asma grave. Resultados: Con base en evidencia, seguridad, costo y realidad local, el grupo nuclear desarrolló respuestas. Mediante proceso Delphi, el grupo amplio de desarrollo sugirió ajustes hasta que se logró el consenso. Conclusión: El documento generado contiene múltiples figuras y algoritmos, está sólidamente basado en evidencia acerca del manejo del asma y fue ajustado para México con participación de diferentes sociedades para su desarrollo; no se incluyeron lineamientos para la crisis asmática.

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This work assessed the effect of increasing microaeration flow rates (1-6 mL min-1 at 28 °C and 1 atm, equivalent to 0.025-0.152 L O2 L-1 feed) on the removal/biotransformation of seven organic micropollutants (OMPs) (three hormones, one xenoestrogen, and three pharmaceuticals), at 200 µg L-1 each, in a lab-scale upflow anaerobic sludge blanket reactor operated at a hydraulic retention time (HRT) of 7.4 h. Additionally, the operational stability of the system and the evolution of its microbial community under microaerobic conditions were evaluated. Microaeration was demonstrated to be an effective strategy to improve the limited removal/biotransformation of the evaluated OMPs in short-HRT anaerobic wastewater treatment systems. The rise in the airflow rate considerably increased the removal efficiencies of all OMPs. However, there seems to be a saturation limit for the biochemical reactions. Then, the best results were obtained with 4 mL air min-1 (0.101 L O2 L-1 feed) (~90%) because, above this flow rate, the efficiency increase was negligible. The long-term exposure to microaerobic conditions (249 days) led the microbiota to a gradual evolution. Consequently, there was some enrichment with species potentially associated with the biotransformation of OMPs, which may explain the better performance at the end of the microaerobic term even with the lowest airflow rate tested.

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Mechanical-Biological Treatment (MBT) is a technology applied to reduce the environmental impacts of urban waste based on stabilizing the organic matter content. As the process is not entirely efficient, the residue can generate methane when it is landfilled. Long-term methane emissions estimation based on models is usually over or underestimated because the actual waste composition after stabilization is generally unknown. This work proposes a single tool to improve the emission estimations of the landfilled MBT waste based on the determination of the biomethane potential test (BMP). Experimental BMP of the crude and stabilized organic fractions of municipal solid waste obtained from an MBT plant were carried out, and the results were used to predict the methane emission from two models, LandGEM (2005) and IPCC (2006). In the LandGEM model, the experimental value of BMP represents the methane potential L0 while in the IPCC model it allowed to obtain the ultimate organic carbon anaerobically degraded (DOCf), based on a linear correlation (R2 = 0.944, p-value < .05) that can be used to obtain the DOCf in a waste of any composition. The results of the long-term (40 years) methane emissions of the stabilized waste disposed on land showed overestimations of up 56.0% (IPCC model) and 259.5% (Landgem model) when default data, instead the actual DOCf were applied in stabilized waste; similar behaviour was observed for the crude waste (23.3% and 241.3% overestimations). Moreover, the impact of the stabilization process revealed methane emission reductions of 5.1% and 20.9% based on LandGEM and IPCC models, respectively.

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Wastewater discharge is a matter of concern as it is the primary source of water pollution. Consequently, wastewater treatment plays a key role in reducing the negative impact that wastewater discharge produce into the environment. Particularly, the effluents produced by textile industry are composed of high concentration of hazardous compounds such as dyes, as well as having high levels of chemical and biological oxygen demand, suspended solids, variable pH, and high concentration of salt. Main efforts have been focused on the development of methods consuming less water or reusing it, and also on the development of dyes with a better fixation capacity. However, the problem of how to treat these harmful effluents is still pending. Different treatment technologies have been developed, such as coagulation-flocculation, adsorption, membrane filtration, reverse osmosis, advanced oxidation, and biological processes (activated sludge, anaerobic-aerobic treatment, and membrane bioreactor). Concerning to biological treatments, even though they are considered as the most environmentally friendly and economic methods, their industrial application is still uncertain. On the one hand, this is due to the costs of treatment plants installation and, on the other, to the fact that most of the studies are carried out with simulated or diluted effluents that do not represent what really happens in the industries. Integrated treatment technologies by combining the efficiency two or more methodologies used to be more efficient for the decontamination of textile wastewater, than treatments used separately. The elimination of hazardous compounds had been reported using combination of physical, chemical, and biological processes. On this way, as degradation products can sometimes be even more toxic than the parent compounds, effluent toxicity assessment is an essential feature in the development of these alternatives. This article provides a critical view on the state of art of biological treatment, the degree of advancement and the prospects for their application, also discussing the concept of integrated treatment and the importance of including toxicity assays to reach an integral approach to wastewater treatment.

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Conventional sewage treatment systems are generally not designed to remove micropollutants, requiring the development of new technologies, such as the combination of biological processes with advanced oxidative processes. The configuration of an anaerobic expanded granular sludge bed (EGSB) reactor stands out for its use of granular biomass and high sludge bed expansion. Ozonation is an advanced oxidative process that stands out as one of the most promising technologies for the degradation of micropollutants. Thus, the present work aimed to evaluate the removal of drugs through the application of ozonation as a polishing process for the effluent of an EGSB reactor that was fed with synthetic sewage. Ozonation was shown to be efficient in the degradation of these compounds, reaching removals above 90%. It was found that the degradation profile of each drug varied according to its chemical structure since some drugs are more susceptible to oxidation than others and since the concentrations of pharmaceuticals are also related to their removal. Moreover, the assessment of risks to the environment and human health confirmed the need to assess the best scenario for risk reduction considering all drugs, since even with almost complete removal of some compounds, the effluents still showed toxicity. Thus, the high removal efficiencies found for the evaluated micropollutants showed that this technique has the potential to be used to improve the quality of biological reactor effluents or even to be combined in effluent reuse systems.

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The coffee processing wastewater (CPWW) requires treatment before being disposed of in the environment or reused due to its high organic and inorganic composition and a low pH. The indigenous microbiota from CPWW is highly diverse and could be selected as inoculums in treatment waste plants. Considering the physico-chemical characteristics of wastewater coffee, we elaborate on steps to select the microbial consortium that showed positive impact via decreasing the pollutant parameters of this effluent. The effectiveness was confirmed using wastewater from different origins with different chemical characteristics. A bacterial consortium composed by Serratia marcescens CCMA 1010 and CCMA 1012, Corynebacterium flavescens CCMA 1006, and Acetobacter indonesiensis CCMA 1002 was selected as the inoculums-based phenotypic assays. The mixed inoculum showed a highly active population (11.18 log CFU mL-1), promoting an 85% decrease in biochemical oxygen demand and a 60% decrease in chemical oxygen demand. There was also an 80% reduction in phosphorus and nitrogen. The final pH changed from 6.0 to 7.5. Additionally, the eco-toxicity using Daphnia similis was reduced by more than 59%. The microbial inoculum was efficient in the biological treatment in CPWWs, demonstrating the efficiency and robustness of the selected strains, independent of the physico-chemical characteristics of wastewater.

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Large volumes of produced water are generated as a byproduct in activities of oil and gas exploitation, which can be reused in agriculture after a treatment process. Activated sludge treatment has been successfully used to remove oil from wastewater, but systematic studies on the toxicity of this effluent using this treatment are scarce in the literature. In this study, it was investigated the performance of an activated sludge system in the treatment of a synthetic produced water under different initial conditions in terms of salinity and oil and grease concentration. Furthermore, it was evaluated this effluent phytotoxicity in the germination, and seedling and plant growths of sunflower and corn seeds using untreated and treated synthetic produced water. Results revealed the activated sludge effectiveness in oil and grease and salinity removal from produced water, viz. high removal efficiency of 99.01 ± 0.28 and 91.07 ± 0.39%., respectively. Untreated produced water showed considerable toxic effects on the germination (74.67 ± 2.31% and 82.67 ± 2.31 for sunflower and corn seeds, respectively) and growth stages of sunflower and corn seed plants. The germination percentage was approximately 100% for both types of seed. The seedling and plant growth of the two seeds irrigated with treated produced water had similar performance when used tap water. These results highlighted the potential reuse as an unconventional water resource for plant irrigation of the synthetic produced water treated by an activated sludge process, which technology has showed high removal performance of salinity and oil.

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