Browsing by Author "Moreira, Irina"
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- Bioaugmented aerobic granular sludge reactor with a dye-decolorizing yeast for dye removal from textile industry wastewaterPublication . Mendes, Marta; Moreira, Irina; Moreira, Patrícia; Pintado, Manuela; Castro, PaulaTextile industry is a worldwide economic activity that generates high volumes of harmfuleffluents used in fabric processing that are discharged in the environment causing potentialdamages 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 areresponsible for toxicity and mutagenic effects on the aquatic life [2]. Biological methods aregenerally considered more environmentally friendly and of major relevance [3]. Therefore,biological alternatives to aid the decolorization of dyes in textile wastewaters need to beimplemented. Aerobic granular sludge (AGS) technology has excellent potential inbiodegradation of many pollutants, due to the anoxic/anaerobic zones within granules and theirincreased tolerance to toxicity [4].The aim of this study is to assess the effectiveness of decolorization of textile effluents using abioaugmented aerobic granular sludge reactor. A proved decolorizing yeast, isolated from atextile wastewater treatment plant, was selected for its dye decolorization capacity, and usedto bioaugment the bioreactor while forming the granules from activated sludge. Theincorporation of the yeast with the granules was followed by plating and following the yeastwithin the microbial community. A commonly used textile azo dye was added to the reactor tofollow the biodegradation by the bioaugmented aerobic granular sludge and the efficiency ofthe process in decolorizing the effluent at varying operational parameters was followed to assessif this is a solution for a safer discharge of such effluents.
- Biodegradation of Carbamazepine and Diclofenac by Bacterial Strain Labrys portucalensisPublication . Bessa, Vânia S.; Moreira, Irina; Murgolo, Sapia; Mascolo, Giuseppe; Castro, Paula M. L.The occurrence of pharmaceuticals in the environment has been a topic of increasing concern. Pharmaceuticals are not completely mineralized in the human body and are released on the sewage systems as the pharmaceutical itself and as their “biologically active” metabolites through excretion, as well as by improper elimination and disposal. Conventional wastewater treatment plants (WWTPs) are not designed to remove these emerging pollutants and they are thus released into the environment. The antiepileptic drug carbamazepine (CBZ) and the non-steroidal anti-inflammatory diclofenac (DCF) are two widely used pharmaceuticals, frequently detected in water bodies, including rivers and groundwater, in concentrations ranging from ng L 1 to mg L 1. These two compounds were classified as medium to high-risk pollutants in WWTP effluents and surface waters. Also, CBZ has been suggested as a molecular marker of wastewater contamination in surface water and groundwater and the European Union included DCF in the watch list of substances Directive to be monitored. In the present study, biodegradation of CBZ and DCF by the bacterial strain Labrys portucalensis F11, a strain able to degrade other pharmaceutical compounds, was assessed; tests were performed with F11 as single carbon and energy source, as well as in presence of 5.9mM of sodium acetate. In assays supplemented with 2.0 and 4.0 µM of CBZ, the compound was no longer detected in the bulk medium after 24hr and 5days, respectively. Complete degradation was achieved in 21 days for 11.0 µM and in 23 days for 21.0 µM. For the highest concentration tested (43.0 µM), 95% of degradation was achieved in 30days. Supplementation with acetate increased the degradation rate of CBZ, for all tested concentrations. In the case of DCF, when supplemented as a single carbon source, approximately 70% of DCF (1.7, 3.3, 8.4, 17.5 and 34.0 µM) was degraded in 30days. Complete degradation was achieved in the presence of acetate for all tested concentrations, at higher degradation rates. The detection of intermediates produced during DCF biodegradation was performed by UPLC-QTOF/MS/MS, which allowed the identification of a range of metabolites. Stoichiometric liberation of chorine occurred and no metabolites were detected at the end of the biodegradation assays suggesting a complete mineralization of DCF. Strain Labrys portucalensis F11 proved to be able to degrade these two top priority environmental contaminants and may be potentially useful for biotechnological applications/environment remediation.
- Biodegradation of carbamazepine by the bacterial strain labrys portucalensis F11 : metabolism and toxicologic studiesPublication . Bessa, Vânia S.; Moreira, Irina; Murgulo, Sapia; Piccirillo, Clara; Mascolo, Giuseppe; Castro, Paula M. L.Background: Occurrence of pharmaceuticals in the environment is a topic of concern. Most pharmaceuticals are not completely mineralized and are released on the sewage systems through excretion and by improper elimination and disposal. Municipal wastewater treatment plants (WWTPs) are not designed to remove them and they are released into the environment. They are classified as persistent microcontaminants due to their continuous release even if at low concentrations. Carbamazepine (CBZ) is an widely used anticonvulsant and has been suggested as a molecular marker of contamination in surface water and groundwater. Method Biodegradation of CBZ by the bacterial strain Labrys portucalensis F11 was tested as sole carbon and energy source (0.04 mM) and in the presence of acetate as primary carbon source. Transformation products (TPs) were detected and identified by UPLCQTOF/MS/MS. Ecotoxicologiacl effects of CBZ and the TPs resultant from biodegradation were evaluated at different trophic levels, i) zooplanckton (Dapnhia magna) and ii) plants (Lipidium sativum). The 24–48 h immobilization of D. magna bioassays were performed following the Standard Operational Procedures of Daphtoxkit FTM. The toxicity was measured as the immobilization of D. magna according to the procedures OCED Guideline 202. The bioassay with L. sativum evaluated the potential toxicity considering the root elongation according to OECD Guideline 208. Results & Conclusions Strain F11 was able to degrade 95% of initial CBZ concentration during 30 days experiment. Supplementation with acetate increased degradation to 100% in 24 days. A group of 12 TPs formed in the microbial process were identified; CBZ degradation by strain F11 proceeds mainly by oxidation, hydroxilation and cleavage of the aromatic ring. The effect of whole biodegradation products on root elongation of L. sativum was practically neglectable; however the same exhibited toxicity to D. magna. Strain Labrys portucalensis F11 proved to be able to degrade CBZ and may be potentially useful for biotechnological applications.
- Novel hydroxyapatite-TiO2 composite material for photocatalytic degradation of diclofenacPublication . Moreira, Irina; Murgolo, S.; Piccirillo, C.; Mascolo, G.; Castro, Paula