Browsing by Author "Moreira, Irina S."
Now showing 1 - 10 of 53
Results Per Page
Sort Options
- Aerobic granular sludge sequencing batch reactor performance under fluorinated pharmaceuticals shock loadingsPublication . Moreira, Irina S.; Amorim, Catarina L.; Ribeiro, Ana R.; Maia, Alexandra S.; Mesquita, Raquel B. R.; Calheiros, Cristina S. C.; Rangel, António O. S. S.; Loosdrecht, Mark C. M.; Tiritan, Maria E.; Castro, Paula M. L.The widespread usage of pharmaceuticals is of increasing concern. Aerobic granular sludge sequencing batch reactors (AGS-SBR) constitute a promising technology for the treatment of wastewaters, however how the removal of carbon and nutrients can be affected by such micropollutants is largely unknown. This study evaluates the impact of different fluorinated drugs (ofloxacin, norfloxacin, ciprofloxacin and fluoxetine) on the performance of an AGS-SBR. During 468 days, a sequence of intermittent, alternating and/or continuous shock loads of pharmaceuticals were apllied to an AGS-SBR and the effects on the main biological processes were evaluated. Here we report on the effect of fluoroquinolones on reactor performnce. The organic removal, measured by COD, was not markedly affected by pharmaceuticals shock loads. Ammonium and nitrite were practically not detected in the bioreactor effluent indicating that the presence of the pharmaceuticals did not inhibit nitrification, whereas accumulation of nitrate in the effluent was observed, indicating that denitrification was affected. Phosphate removal was affected to some extent. There was no evidence of biodegradation whereas adsorption of the target pharmaceuticals to the AGS was observed, which were gradually released into the medium after withdrawal from the inlet stream.
- Aerobic granular sludge: treatment of wastewaters containing toxic compoundsPublication . Amorim, Catarina L.; Moreira, Irina S.; Duque, Anouk F.; Loosdrecht, Mark C. M. van; Castro, P. M. L.Aerobic Granular Sludge (AGS) has been successfully applied for carbon, nitrogen and phosphorous removal from wastewaters, in a single tank, reducing the space and energy requirements. This is especially beneficial for, often space restricted, industrial facilities. Moreover, AGS holds a promise for the toxic pollutants removal, due to its layered and compact structure and the bacteria embedding in a protective extracellular polymeric matrix. These outstanding features contribute to AGS tolerance to toxicity and stability. Strategies available to deal with toxic compounds, namely granulation with effluents containing toxics and bioaugmentation, are addressed here. Different applications for the toxics/micropollutants removal through biosorption and/or biodegradation are presented, illustrating the technology versatility. The anthropogenic substances effects on system performance and bacterial populations established within AGS are also addressed. Combination of contaminants removal to allow water discharge, and simultaneous valuable products recovery are presented as final remark.
- Bacterial community and system performance of an aerobic granular sludge reactor treating pharmaceutical wastewaterPublication . Amorim, Catarina L.; Moreira, Irina S.; Ribeiro, Ana R.; Tiritan, Maria E.; Henriques, Isabel S.; Castro, Paula M.L.Pharmaceuticals often reach wastewater treatment systems where low removal rates are observed. In the present study the potential impact of a mixture of such micro-pollutants on an aerobic granular sludge-sequencing batch reactor (AGS-SBR) was investigated using a lab-scale bioreactor. COD and P- removals were affected due to the load of pharmaceuticals resulting in a decrease of the COD uptake and the P-release during the anaerobic feeding phase, but the discharge limits were not exceeded. Nevertheless, both processes returned to its normal operation after resuming the pharmaceuticals feeding. The nitrification process was also affected but the activity of bacteria responsible for both nitrification steps was able to recover. The exposure to the pharmaceuticals induced alterations in the bacterial community structure.
- Bacterial degradation of perfluorooctane sulfonic acid (PFOS): detection of by-products by target and non-target analysisPublication . Wijayahena, Mindula K.; Moreira, Irina S.; Wallace, Joshua S.; Castro, Paula M. L.; Aga, Diana S.Introduction: Per- and poly-fluoroalkyl substances (PFAS) are highly fluorinated synthetic chemicals with a wide variety of uses1,2. The carbon- fluorine bonds exhibit very high bond dissociation energies: around 536 kJ/mol, making PFAS generally resistant to degradation by oxidation, thermal treatment, and biological mechanisms, which has led to their classification as “forever chemicals”3. Strategies to enhance the biodegradation of these compounds are of great interest, such as identifying bacterial species that may be used for bioaugmentation. Labrys portucalensis F11 is an aerobic bacterium that has been isolated in Portugal and can degrade fluorinated pharmaceuticals, fluorobenzene, and fluoxetine4,5. This F11 strain has the ability to cleave C-F bonds in these fluorinated organic compounds and was therefore tested for its ability to degrade perfluorooctane sulfonate (PFOS), the most frequently detected PFAS in the environment. Objectives: To determine whether the F11 bacteria strain can degrade PFOS; To identify biodegradation products by non-targeted analysis. Conclusions: Labrys portucalensis strain F11 degraded PFOS. Shorter-chain PFAS, from C7 to C3 were formed as metabolites. Non-target analysis facilitated the identification of the unsaturated and hydrogenated C8 compounds. IMS separation exhibited the separation of isomers of PFOS as well as defluorinated PFOS isomers including isomers of H-PFOS and isomers of unsaturated PFOS.
- Bacterial strain labrys portucalensis F11 degrades the neonicotinoid insecticide thiamethoxam and removes toxicityPublication . Boufercha, Oumeima; Monforte, Ana R.; Boudemagh, Allaoueddine; Ferreira, António C.; Castro, Paula M. L.; Moreira, Irina S.
- Bacterial strain rhodococcus sp. ED55 degrades endocrine disrupring chemicals in wastewaterPublication . Moreira, Irina S.; Ely, Cyntia; Bassin, João Paulo; Dezotti, Márcia W. C.; Gonçalves, David M.; Castro, Paula M. L.
- Bioaugmentation of aerobic granular sludge with dye-decolorizing yeast for textile industrial wastewaterPublication . Mendes, Marta; Moreira, Irina S.; Moreira, Patrícia; Pintado, Manuela; Castro, Paula M. L.A sequencing batch reactor (SBR) inoculated with activated sludge and bioaugmented with a dye-decolorizing yeast strain—Yarrowia lipolytica (HOMOGST27AB) was assembled to form yeastbioaugmented aerobic granular sludge (AGS). The bioaugmented AGS-SBR was operated for the treatment of synthetic saline wastewater (12 g L1) intermittently fed with a reactive textile dye (Navy Everzol ED) at 25, 15, and 7.5 mg L1. Dye degradation did not occur, although some dye adsorbed to the granules. AGS-SBR performance in removing carbon and nitrogen was good and was not affected by the dye addition. Bioaugmentation with the yeast Y. lipolytica (HOMOGST27AB) occurred with success, proved by sequencing samples from granules throughout the reactor operation. The AGScore microbiome gathered essentially microorganisms from the Proteobacteria and Bacteroidetes phyla.The microbial profile showed a dynamic microbiome established at Phase I of the operation, with ahigh decrease in the abundance of Ignavibacterium from the initial biomass to the granules formedand an increase in Actinobacteria, Cytophagia, Flavobacteria, and Alphaproteobacteria in the remainingphases of the bioreactor operation.
- Bioaugmented aerobic granular sludge reactor with a dye-decolorizing yeast for dye removal from textile industry wastewaterPublication . Mendes, Marta; Moreira, Irina S.; Moreira, Patrícia R.; Pintado, Manuela; Castro, Paula M. L.Textile industry is a worldwide economic activity that generates high volumes of harmful effluents used in fabric processing that are discharged in the environment causing potential damages to the aquatic ecosystems [1]. These discharged effluents loaded with synthetic dyes, salt and other chemicals, are resistant to biodegradation and persistent in water, and are responsible for toxicity and mutagenic effects on the aquatic life [2]. Biological methods are generally considered more environmentally friendly and of major relevance [3]. Therefore, biological alternatives to aid the decolorization of dyes in textile wastewaters need to be implemented. Aerobic granular sludge (AGS) technology has excellent potential in biodegradation of many pollutants, due to the anoxic/anaerobic zones within granules and their increased tolerance to toxicity [4]. The aim of this study is to assess the effectiveness of decolorization of textile effluents using a bioaugmented aerobic granular sludge reactor. A proved decolorizing yeast, isolated from a textile wastewater treatment plant, was selected for its dye decolorization capacity, and used to bio augment the bioreactor while forming the granules from activated sludge. The incorporation of the yeast with the granules was followed by plating and following the yeast within the microbial community. A commonly used textile azo dye was added to the reactor to follow the biodegradation by the bioaugmented aerobic granular sludge and the efficiency of the process in decolorizing the effluent at varying operational parameters was followed to assess if this is a solution for a safer discharge of such effluents.
- Biodegradation and Metabolic Pathway of 17 beta-Estradiol by Rhodococcus sp. ED55Publication . Moreira, Irina S.; Murgolo, Sapia; Mascolo, Giuseppe; Castro, Paula M. L.Endocrine disrupting compounds (EDCs) in the environment are considered a motif of concern, due to the widespread occurrence and potential adverse ecological and human health effects. The natural estrogen, 17 beta-estradiol (E2), is frequently detected in receiving water bodies after not being efficiently removed in conventional wastewater treatment plants (WWTPs), promoting a negative impact for both the aquatic ecosystem and human health. In this study, the biodegradation of E2 by Rhodococcus sp. ED55, a bacterial strain isolated from sediments of a discharge point of WWTP in Coloane, Macau, was investigated. Rhodococcus sp. ED55 was able to completely degrade 5 mg/L of E2 in 4 h in a synthetic medium. A similar degradation pattern was observed when the bacterial strain was used in wastewater collected from a WWTP, where a significant improvement in the degradation of the compound occurred. The detection and identification of 17 metabolites was achieved by means of UPLC/ESI/HRMS, which proposed a degradation pathway of E2. The acute test with luminescent marine bacterium Aliivibrio fischeri revealed the elimination of the toxicity of the treated effluent and the standardized yeast estrogenic (S-YES) assay with the recombinant strain of Saccharomyces cerevisiae revealed a decrease in the estrogenic activity of wastewater samples after biodegradation.
- Biodegradation and metabolic pathway of the neonicotinoid insecticide thiamethoxam by Labrys portucalensis F11Publication . Boufercha, Oumeima; Monforte, Ana R.; Boudemagh, Allaoueddine; Ferreira, António C.; Castro, Paula M. L.; Moreira, Irina S.Thiamethoxam (TMX) is an effective neonicotinoid insecticide. However, its widespread use is detrimental to non-targeted organisms and water systems. This study investigates the biodegradation of this insecticide by Labrys portucalensis F11. After 30 days of incubation in mineral salt medium, L. portucalensis F11 was able to remove 41%, 35% and 100% of a supplied amount of TMX (10.8 mg L−1) provided as the sole carbon and nitrogen source, the sole carbon and sulfur source and as the sole carbon source, respectively. Periodic feeding with sodium acetate as the supplementary carbon source resulted in faster degradation of TMX (10.8 mg L−1); more than 90% was removed in 3 days. The detection and identification of biodegradation intermediates was performed by UPLC-QTOF/MS/MS. The chemical structure of 12 metabolites is proposed. Nitro reduction, oxadiazine ring cleavage and dechlorination are the main degradation pathways proposed. After biodegradation, toxicity was removed as indicated using Aliivibrio fischeri and by assessing the synthesis of an inducible β-galactosidase by an E. coli mutant (Toxi-Chromo test). L. portucalensis F11 was able to degrade TMX under different conditions and could be effective in bioremediation strategies.