Browsing by Author "Moreira, I. S."
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- Biodegradation of bisphenol A and bisphenol S by labrys portucalensis F11Publication . Novo, A.; Moreira, I. S.; Murgolo, S.; Mascolo, G.; Castro, P. M. L.
- Biodegradation of carbamazepine by the bacterial strain labrys portucalensis F11Publication . Bessa, V. S.; Moreira, I. S.; Murgolo, Sapia; Piccirillo, Clara; Mascolo, Giuseppe; Castro, P. M. L.Introduction and Objectives: The occurrence of pharmaceuticals in the environment is a topic of concern. Most pharmaceuticals are not completely mineralized in the human body and are released to the sewage systems as the pharmaceutical itself and as their “biologically active” metabolites Wastewater treatment plants (WWTPs) are not designed to remove them and they are released into the environment. Despite generally found at low concentrations (ranging from ngL−1 to μgL−1), they are classified as persistent microcontaminants due to their continuous release. Carbamazepine (CBZ) is a widely used anticonvulsant which has been found in different environmental compartments and has been suggested as a molecular marker of contamination in surface water and groundwater. In the present study, biodegradation of CBZ by strain Labrys Portucaliensis F11 was assessed. Transformation products (TPs) resulting from CBZ degradation were analysed. Methodology: CBZ biodegradation assays were performed in minimal salts medium (MM) supplemented with 2.0, 4.0, 10.0, 20.0 and 40.0 𝜇M of CBZ as a sole carbon and energy source and in the presence of acetate (5.9mM); CBZ was quantified by High Performance Liquid Chromatography (HPLC); Transformation products (TPs) were detected and identified by UPLCQTOF/MS/MS; Ecotoxicological effects of cultures containing CBZ and of cultures containing the TPs after microbial degradation were assessed using Daphnia magna (OCED Guideline 202) and Lepidium sativum (OECD Guideline 208). Highlights: Supplementation with a second carbon source had a positive effect on CBZ degradation by strain Labrys Portucalensis F11; CBZ degradation by strain F11 proceeds mainly by oxidation, hydroxilation, hydrolysis and cleavage of the aromatic ring; CBZ TPs were detected until the end of the experiment time; CBZ and transformation products exhibited high toxicity on D. magna whereas inhibition of root elongation of L. sativum was practically neglectable.
- Biodegradation of endocrine disrupting compounds by bacterial communities from contaminated environments in MacauPublication . Moreira, I. S.; Lebel, A.; Gonçalves, D.; Castro, P. M. L.Endocrine disrupting chemicals (EDCs) is a group of a wide range of chemicals that can alter the hormonal and homeostatic systems of organisms. An increasing concern on possible human and environmental health effects of these compounds is due to the alarming evidence from scientific studies indicating negative effects in the reproductive system of aquatic species, wildlife, and humans as a result of exposure to very low (ng L−1 ) concentrations [1]. There is a long list of chemicals with estrogenic activity, which include natural estrogens and synthetic or industrial chemicals such as bisphenol A, and more recently Bisphenol S. Incomplete removal of these chemicals in wastewater treatment plants lead to contamination of the receiving aquatic environment. The situation of The Pearl River Delta (PRD), also known as Guangdong—Hong Kong—Macau Greater Bay Area, is of particular concern due to the high industrialization and for being one of the most densely urbanized regions in the world [2,3]. In the present study, soil samples obtained near a discharge site of a sewage treatment plant and activated sludge samples collected from an aeration tank of the same station, located in Coloane, Macao, were used for the establishment of selective enrichments with bisphenol A (BPA), bisphenol S (BPS), 17β-estradiol (E2) and 17α- ethynilestradiol (EE2). Total removal of 3.5mg L-1 of E2 and EE2 and 15mg L-1 of BPA was achieved 21 days after starting the enrichment. For BPS, removal of 91% was observed in the enrichment from soil and 68% in the enrichment from activated sludge, fed with 15 mg L-1 , during 28 days. Removal includes degradation and adsorption to particles from soil and sludge. After two month enrichment, the consortia were able to completely degrade 10 mg L -1 of BPA in three days, while BPS was not degraded. For the hormones, degradation of E2 varied between 40 and 100%; degradation of EE2 varied between 36 and 77%, in 15 days. A total of 28 strains were isolated from the degrading consortia. The strains were identified by 16S rRNA gene sequencing and half of these were taxonomically affiliated with β-proteobacteria. Degradation of the compounds by the isolated bacteria was tested first on minimal agar plates and then in liquid media as sole carbon source. The maximum extent of degradation obtained was 67% for EE2 and 100% for E2, supplied at 4.5 mg L-1 , and 23% for BPA and 34% for BPS, supplied at 9.5 mg L-1 , during 28 days. The achieved degradation for BPS is particularly interesting, since this compound is considered recalcitrant to biodegradation and likely to accumulate in the environment. The isolated strains represent valuable candidates for in situ bioremediation of contaminated soils and waters. Promising results were obtained by a strain identified as Castellaniella sp. ED55, able to degrade the four compounds at different extents. Further studies are ongoing to optimize the degradation of the compounds by this strain and to deepen the knowledge about the mechanisms of degradation, including genome sequencing and transcriptomic experiments.
- Biphasic apatite-carbon materials derived from pyrolysed fish bones for effective adsorption of persistent pollutants and heavy metalsPublication . Piccirillo, C.; Moreira, I. S.; Novais, R. M.; Fernandes, A. J. S.; Pullar, R. C.; Castro, P. M. L.Biphasic apatite-carbon biochar-type materials were prepared from pyrolysed cod fish bones and were assessed for the adsorption of persistent organic pollutants (pharmaceuticals diclofenac and fluoxetine), and heavy metals (Pb(II)). The materials, prepared with a simple pyrolysis process at different temperatures (200–1000 °C), were characterised with XRD, FTIR, Raman and SEM. Results showed that the pyrolysis temperature had a significant effect on the features/composition of the materials: up to 800 °C, carbonate apatite Ca10(PO4)6(CO3) was the main component, while for higher temperatures oxyapatite Ca10(PO4)6O was the dominant phase. Graphitic carbon was also detected. The mixed apatite-carbon products (bone char) exhibited high adsorption efficiency. Graphite carbon was the main adsorber for the pharmaceuticals, the best performing material being that pyrolysed at 1000 °C. Xm values of 43.29 and 55.87 mg/g were observed (Langmuir fitting), while KF values of 5.40 and 12.53 (mg/g)(L/mg)nF were obtained with the Freundhlich model (diclofenac and fluoxetine respectively). This is the first time that a biochar-like material has been used for fluoxetine adsorption. For Pb (II), the powder pyrolysed at 600 °C was the most effective, with the apatite playing a key role (Xm = 714.24 mg/g). This work shows that a by-product of the fish industry could be converted into efficient materials for environmental remediation; according to the pyrolysis conditions, powders effective in the removal of either organics or heavy metals can be obtained. Moreover, with pyrolysis at intermediate temperatures, materials capable of adsorbing both kinds of pollutants can be produced, even if less efficient.
- Cloning, nucleotide sequence and expression of Fluorobenzene Dioxygenase from Labrys portucalensis strain F11Publication . Moreira, I. S.; Kirschner, A.; Carvalho, M. F.; Castro, P. M. L.; Janssen, D. B.
- Degradation of difluorobenzenes by the wild strain Labrys portucalensisPublication . Moreira, I. S.; Carvalho, M. F.; Amorim, Catarina L.; Janssen, D. B.; Castro, Paula M. L.
- Enrichment of bacterial strains for the biodegradation of diclofenac and carbamazepine from activated sludgePublication . Bessa, V. S.; Moreira, I. S.; Tiritan, M. E.; Castro, P. M. L.Carbamazepine and diclofenac have been pointed out as important markers for environmental pollution by pharmaceuticals. This study reports on the isolation of bacterial strains capable to degrade these micropollutants from activated sludge of a municipal wastewater treatment plant (WWTP). After selective enrichments, one strain able to degrade diclofenac and two strains able to degrade carbamazepine were isolated. The strains were identified by 16S rRNA gene sequencing. Strain Brevibacterium sp. D4 was able to biodegrade 35% of 10 mg L−1 of diclofenac as a sole carbon source; periodic feeding with acetate as a supplementary carbon source resulted in enhancing biodegradation to levels up to 90%, with a concomitant increase of the biodegradation rate. Strains Starkeya sp. C11 and Rhizobium sp. C12 were able to biodegrade 30% of 10 mg L−1 of carbamazepine as a sole carbon source; supplementation with acetate did not improve the biodegradation of carbamazepine by these strains. The activated sludge harboured bacteria capable to degrade the two top priority environmental contaminants and may be potentially useful for biotechnological applications.
- Enrichment of bacterial strains for the biodegradation of endocrine disrupting compounds from sediments of the Pearl River Delta (PRD)Publication . Moreira, I. S.; Lebel, A.; Gonçalves, D.; Castro, P. M. L.Introduction: Endocrine disrupting chemicals (EDCs) are those which alter the homeostasis, reproduction, development and/or behavior of organisms. Negative effects have been reported on aquatic species, wildlife, and humans due to exposure to very low (ng L−1) concentrations. Wastewater treatment plants are not able to completely remove these chemicals, contributing to the contamination of receiving water bodies. The situation of The Pearl River Delta (PRD) is of particular concern due to the high industrialization and dense urbanization. In the present study, bacteria degrading estradiols and bisphenols were isolated from sludge from an aeration tank and sediments obtained near a discharge site of a WWTP located in Coloane, Macao. Conclusions: The isolated strains represent valuable candidates for in situ bioremediation of contaminated soils and waters. Promising results were obtained by strain Castellaniella sp. ED55, able to degrade the four compounds at different extents. Further studies are ongoing to optimize the degradation of the compounds and to deepen the knowledge about the mechanisms of degradation including genome sequencing and transcriptomic experiments.
- Mangroves as a source of polyethylene terephthalate (PET) degrading bacteriaPublication . Saidu, M. B.; Gonçalves, D.; Castro, P. M. L.; Moreira, I. S.Polyethylene terephthalate (PET) is one of the most widely used plastics, and its accumulation in the environment has become an issue of great concern. PET wastes constitute a critical source of pollution to the environment, with important impacts on ecosystems and human health. One possibility to address this problem is to identify microorganisms that may be able to naturally degrade the compound for downstream applications. This study investigated the biodegradation of PET films in soil in the presence or absence of mangrove plants, and with or without bioaugmentation with bacterial isolates of the genus Bacillus and Enterococcus. The experiment was performed in an open garden for ten months. At the end of this period, biodegradation assays of PET monomers and intermediate were further performed using bacterial consortia isolated from the soil of the different treatments. Terephthalic acid (TPA) and bis-2-hydroxyethyl terephthalate (BHET) were added to liquid medium as the sole carbon sources and incubated for 10 days at 30oC. Growth of the consortia was monitored by spectrophotometry, and degradation was followed by HPLC analysis of aliquot samples. The preliminary results from gravimetry analysis showed no significant changes in PET films, regardless of the treatment. On the other hand, total degradation of TPA and BHET was observed for all assays independently of treatment. The results suggest that although direct biodegradation of PET may be challenging to accomplish, bacteria capable of degrading the intermediates and monomers of PET are readily available in the natural environment.
- Microbial consortia selection for the development of an innovative nature-based solution for air pollutants remediationPublication . Moreira, I. S.; Novo, B.; Monteiro, P.; Pinto, G.; Castro, P. M. L.; Alves, A.; Tacão, M.; Alves, M.Air pollutants, like benzene, toluene, and xylene (BTX), pose significant health and environmental risks being associated with 6.7 million premature deaths annually. Despite plants natural air purification capabilities in green infrastructures, high pollution levels in cities can hinder urban greening when tolerance levels are exceeded. Therefore, this study aimed to develop plant-beneficial microbial consortia with the capacity to degrade air pollutants envisioning their application as plant inoculants to promote plants’ resilience and their efficiency in air purification. Leaves and rhizosphere samples from Tilia sp., Rhododendron sp. and Euonymus sp. were collected in Porto city (Portugal), in an area with high traffic-derived air pollution (NOx, benzene – as in Qualar database). Total pigments concentration showed low variability among plants genera (from 3.24 ± 0.45 to 3.57 ± 0.30 µmol g-1). The neutral to alkaline pH of leaf extracts and high relative water content results indicated good tolerance of the sampled plant genera to pollutants. To select BTX-degrading microbial consortia, leaves and rhizosphere samples were incubated with 300ppm of BTX as the only carbon source, far exceeding EU limits. BTX concentration was monitored through GC-FID. Microbial strains within BTX degrading consortia were identified through sequencing of microbial phylogenetic markers.While leaf samples showed no BTX degradation, rhizosphere samples from all three plant genera displayed significant degradation after 7 to 14 days. Remarkably, in a Rhododendron sp. sample, only 3.8% of the initial BTX concentration remained after 14 days, indicating efficient pollutant removal. Among the fungi genera detected were Penincillium sp., Umbelopsis sp, Fusarium sp. and Clonostachys sp. with species known for their role in plant growth promotion. The obtained microbial consortia have the potential to be used as plant inoculants to promote air remediation.