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- Laccase bioconjugate and multi-walled carbon nanotubes-based biosensor for bisphenol A analysisPublication . Bravo, Iria; Prata, Mariana; Torrinha, Álvaro; Delerue-Matos, Cristina; Lorenzo, Encarnación; Morais, SimoneBisphenol A (BPA) is an endocrine disruptor compound that has been detected in aquatic ecosystems. In this work, the development of an electrochemical biosensor for BPA determination based on laccase from Trametes versicolor is reported. A bioconjugate was optimized to maximize the biosensor electrocatalytic activity and stability, which for the first time involved the synergistic effect of this specific enzyme (6.8 UmL−1), chitosan (5 mgmL−1) and the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate in an optimum 5:5:2 (v/v/v) proportion. This bioconjugate was deposited onto a screen-printed carbon electrode previously modified with multi-walled carbon nanotubes (MWCNTs). Nanostructuration with MWCNTs enlarged the electrocatalytic activity and surface area, thus improving the biosensor performance. The BPA electrochemical reaction follows an EC mechanism at the optimum pH value of 5.0. Linearity up to 12 µM, a sensitivity of (6.59 ± 0.04) × 10-2 μAμM−1 and a detection limit of 8.4 ± 0.3 nM were obtained coupled with high reproducibility (relative standard deviations lower than 6%) and stability (87% of the initial response after one month). The developed biosensor was employed to the analysis of BPA in river water displaying appropriate accuracy (94.6–97.9%) and repeatability (3.1 to 6% relative standard deviations) proving its high potential applicability for in situ environmental analysis.
- Polycyclic aromatic hydrocarbons in commercial squids from different geographical origins: levels and risks for human consumptionPublication . Gomes, Filipa; Oliveira, Marta; Ramalhosa, Maria João; Delerue-Matos, Cristina; Morais, SimoneThe concentrations of 18 polycyclic aromatic hydrocarbons (PAHs) were determined in five commercially valuable squid species from different geographical origins (Atlantic, Indic and Pacific Oceans). Out of the 18 quantified PAHs (the 16 PAHs considered by US EPA as priority pollutants, dibenzo(a,l)pyrene and benzo(j)fluoranthene) only dibenz(a,h)anthracene was not detected. The total concentrations of PAHs varied by a factor of more than 100-fold, from 0.22 (Loligo gahi) to 60.9 lg/kg ww (Loligo reynaudii). Intraand inter-specific variability of PAH levels was statistically assessed. Nine carcinogenic (probable/possible) PAHs accounted for 1% (L. reynaudii) to 26% (Loligo opalescens) of the total PAHs content being the main contributors naphthalene (in Loligo duvaucelii, L. reynaudii and Loligo vulgaris species), chrysene (in L. opalescens) and indeno(1,2,3-cd)pyrene (in L. gahi). PAHs source analysis indicated that four of the five zones of capture of the different squid species are significantly affected by both petrogenic and pyrolytic sources. Assessment of the target carcinogenic risks, established by the US EPA, suggested that L. gahi (Atlantic Ocean) and L. opalescens (from Pacific Ocean) may pose additional risks for consumers, if not eaten in moderation, derived from benzo(a)pyrene ingestion.
- Firefighters exposure to fire emissions: Impact on levels of biomarkers of exposure to polycyclic aromatic hydrocarbons and genotoxic/oxidative-effectsPublication . Oliveira, Marta; Costa, Solange; Vaz, Josiana; Fernandes, Adília; Slezakova, Klara; Delerue-Matos, Cristina; Teixeira, João Paulo; Carmo Pereira, Maria; Morais, SimoneFirefighters represent one of the riskiest occupations, yet due to the logistic reasons, the respective exposure assessment is one of the most challenging. Thus, this work assessed the impact of firefighting activities on levels of urinary monohydroxyl-polycyclic aromatic hydrocarbons (OHPAHs; 1-hydroxynaphthalene, 1-hydroxyacenaphthene, 2-hydroxyfluorene, 1-hydroxyphenanthrene, 1-hydroxypyrene, 3-hydroxybenzo(a)pyrene) and genotoxic/oxidative-effect biomarkers (basal DNA and oxidative DNA damage) of firefighters from eight firehouses. Cardiac frequency, blood pressure and arterial oxygen saturation were also monitored. OHPAHs were determined by liquid-chromatography with fluorescence detection, while genotoxic/oxidative-effect biomarkers were assessed by the comet assay. Concentrations of total OHPAHs were up to 340% higher (p ≤ 0.05) in (non-smoking and smoking) exposed workers than in control subjects (non-smoking and non-exposed to combat activities); the highest increments were observed for 1-hydroxynaphthalene and 1-hydroxyacenaphthene (82–88% of ∑OHPAHs), and for 2-hydroxyfluorene (5–15%). Levels of biomarker for oxidative stress were increased in non-smoking exposed workers than in control group (316%; p ≤ 0.001); inconclusive results were found for DNA damage. Positive correlations were found between the cardiac frequency, ∑OHPAHs and the oxidative DNA damage of non-smoking (non-exposed and exposed) firefighters. Evidences were raised regarding the simultaneous use of these biomarkers for the surveillance of firefighters’ health and to better estimate the potential short-term health risks.
- Life Cycle Assessment and Life Cycle Cost of an Innovative Carbon Paper Sensor for 17α-Ethinylestradiol and Comparison with the Classical Chromatographic MethodPublication . Martins, Florinda; Torrinha, Álvaro; Delerue-Matos, Cristina; Morais, SimoneNowadays there is a growing concern with the environment and sustainability, which means that better methods, including pollutants analysis, with less consumption of materials, organic solvents, and energy, need to be developed. Considering the almost inexistent information about the topic, the main goal of this work was to compare the environmental impacts of two analytical methods, a traditional one based on liquid chromatography with fluorescence detection and a newly developed carbon paper sensor. The selected analyte was 17α-ethinylestradiol, which is a contaminant of emergent concern in aquatic ecosystems due to its endocrine disruptor behavior. The life cycle assessment data showed that the sensor detection presents an almost negligible environmental impact when compared with the extraction step (the same for both methods) and the liquid chromatographic determination (roughly 80 times higher than with the sensor). The sensor values for all categories of damage are below 3% of the total method impacts, i.e., 1.6, 1.9, 2.4, and 2.9% for resources, climate change, human health, and ecosystem quality. The extraction represents 98.1% of the sensor environmental impacts (and 99.6% of its life cycle costing) and 38.8% of the chromatographic method. This study evidences the need of developing and applying greener analytical (detection and extraction) strategies
- Human Biomonitoring of Selected Hazardous Compounds in Portugal: Part I—Lessons Learned on Polycyclic Aromatic Hydrocarbons, Metals, Metalloids, and PesticidesPublication . Pena, Angelina; Duarte, Sofia; Pereira, André M. P. T.; Silva, Liliana J. G.; Laranjeiro, Célia S. M.; Oliveira, Marta; Lino, Celeste; Morais, SimoneHuman biomonitoring (HBM) data provide information on total exposure regardless of the route and sources of exposure. HBM studies have been applied to quantify human exposure to contaminants and environmental/occupational pollutants by determining the parent compounds, their metabolites or even their reaction products in biological matrices. HBM studies performed among the Portuguese population are disperse and limited. To overcome this knowledge gap, this review gathers, for the first time, the published Portuguese HBM information concerning polycyclic aromatic hydrocarbons (PAHs), metals, metalloids, and pesticides concentrations detected in the urine, serum, milk, hair, and nails of different groups of the Portuguese population. This integrative insight of available HBM data allows the analysis of the main determinants and patterns of exposure of the Portuguese population to these selected hazardous compounds, as well as assessment of the potential health risks. Identification of the main difficulties and challenges of HBM through analysis of the enrolled studies was also an aim. Ultimately, this study aimed to support national and European policies promoting human health and summarizes the most important outcomes and lessons learned through the HBM studies carried out in Portugal
- Potential of Portuguese vine shoot wastes as natural resources of bioactive compoundsPublication . Moreira, Manuela M.; Barroso, M. Fátima; Porto, João Vasconcellos; Ramalhosa, Maria João; Švarc-Gajić, Jaroslava; Estevinho, Letícia; Morais, Simone; Delerue-Matos, CristinaSince annually a high amount of wastes is produced in vine pruning, the aim of this study was to evaluate the potential of vine shoots from two Portuguese grape varieties (Touriga Nacional - TN and Tinta Roriz - TR) to be used as a natural source of phenolic compounds. To reach this goal, three techniques were explored, namely microwave-assisted extraction (MAE), subcritical water extraction (SWE) and conventional extraction (CE). The phenolic composition of the extracts, antioxidant and biological activities were evaluated by spectrophotometry and chromatography. MAE and SWE produced the highest concentrated extracts. TR vine shoot variety had the highest antioxidant activity and total phenolic (32.1±0.9mggallicacidequivalents/g dry sample), as well as flavonoid content (18.7±1.2mgepicatechinequivalents/g dry sample). For the first time, the biological activity of the vine shoot extracts was tested. Results demonstrated that all of them had antimicrobial potential against different bacteria and yeasts, and the ability of inhibiting α-amylase and acetylcholinesterase enzymes, with MAE TR extracts being the most efficient. HPLC analysis enabled the identification of different phenolic compounds, with gallic acid, catechin, myricetin and kaempferol-3-O-rutinoside being the main contributors to the phenolic composition. Portuguese vine shoot wastes could serve as easily accessible source of natural antioxidants for the food or pharmaceutical industries.
- Assessment of air quality in preschool environments (3-5 years old children) with emphasis on elemental composition of PM10 and PM2.5Publication . Oliveira, Marta; Slezakova, Klara; Delerue-Matos, Cristina; Pereira, Maria Carmo; Morais, SimoneThis study evaluated concentrations of main air pollutants in a Portuguese preschool (indoors/outdoors) environment, with emphasis on elemental characterization of different PM fractions, and estimated risks for the pupils (aged 3-5 years). With exception to total volatile organic compounds, levels of PM10, PM2.5, CO, CO2, and formaldehyde were below legislative guidelines. Calcium, sodium, aluminium, and potassium were the most abundant elements in indoor PM (82-84% of the analysed content) resulting mainly from crustal sources. Carcinogenic elements (1-2% of the indoor analysed content) were mostly PM2.5- bound (83-91%). Indoor-to-outdoor ratios of individual elements indicated contributions of indoor origin and from penetration of outdoor emissions indoors; trace metals were associated with ambient anthropogenic emissions (namely traffic). Non-carcinogenic and carcinogenic risks from overall preschool exposure were acceptable for children; for adults carcinogenic risks exceeded (4-11 times) the USEPA recommend value of 10-6, being 8-40 times higher than for children.
- Evaluation of the adsorption potential of biochars prepared from forest and agri-food wastes for the removal of fluoxetinePublication . Fernandes, Maria João; Moreira, Manuela M.; Paíga, Paula; Dias, Diogo; Bernardo, Maria; Carvalho, Maria Manuela; Lapa, Nuno; Fonseca, Isabel; Morais, Simone; Figueiredo, Sónia; Delerue-Matos, CristinaTwelve biochars from forest and agri-food wastes (pruning of Quercus ilex, Eucalyptus grandis, Pinus pinaster, Quercus suber, Malus pumila, Prunus spinosa, Cydonia oblonga, Eriobotrya japonica, Juglans regia, Actinidia deliciosa, Citrus sinensis and Vitis vinifera) were investigated as potential low-cost and renewable adsorbents for removal of a commonly used pharmaceutical, fluoxetine. Preliminary adsorption experiments allowed to select the most promising adsorbents, Quercus ilex, Cydonia oblonga, Eucalyptus, Juglans regia and Vitis vinifera pruning material. They were characterized by proximate, elemental and mineral analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, determination of specific surface area and pH at the point of zero charge. Batch and equilibrium studies were performed, and the influence of pH was evaluated. The equilibrium was reached in less than 15 min in all systems. The maximum adsorption capacity obtained was 6.41 mg/g for the Eucalyptus biochar, which also demonstrated a good behavior in continuous mode (packed column).
- Structural, physical, and chemical modifications induced by microwave heating on native agar-like galactansPublication . Sousa, Ana M. M.; Morais, Simone; Abreu, Maria H.; Pereira, Rui; Sousa-Pinto, Isabel; Cabrita, Eurico J.; Delerue-Matos, Cristina; Gonçalves, Maria PilarNative agars from Gracilaria vermiculophylla produced in sustainable aquaculture systems (IMTA) were extracted under conventional (TWE) and microwave (MAE) heating. The optimal extracts from both processes were compared in terms of their properties. The agars’ structure was further investigated through Fourier transform infrared and NMR spectroscopy. Both samples showed a regular structure with an identical backbone, β-D-galactose (G) and 3,6-anhydro-α-L-galactose (LA) units; a considerable degree of methylation was found at C6 of the G units and, to a lesser extent, at C2 of the LA residues. The methylation degree in the G units was lower for MAEopt agar; the sulfate content was also reduced. MAE led to higher agar recoveries with drastic extraction time and solvent volume reductions. Two times lower values of [η] and Mv obtained for the MAEopt sample indicate substantial depolymerization of the polysaccharide backbone; this was reflected in its gelling properties; yet it was clearly appropriate for commercial application in soft-texture food products.
- Bioactive Lipids of Seaweeds from the Portuguese North Coast: Health Benefits versus Potential ContaminationPublication . Soares, Cristina; Sousa, Sara; Machado, Susana; Vieira, Elsa; Carvalho, Ana P.; Ramalhosa, Maria João; Morais, Simone; Correia, Manuela; Oliva-Teles, MT; Domingues, Valentina; Delerue-Matos, CristinaThe total lipid content and lipidic profile of seaweeds harvested in the North Coast and purchased in Portugal were determined in this paper. The amount of total lipids in the different species of seaweeds varied between 0.7 ± 0.1% (Chondrus crispus) and 3.8 ± 0.6% (Ulva spp.). Regarding the fatty acid content, polyunsaturated fatty acids (PUFA) ranged between 0–35%, with Ulva spp. presenting the highest amount; monounsaturated fatty acids (MUFA) varied between 19 and 67%; and saturated fatty acids (SFA) were predominant in C. crispus (45–78%) and Gracilaria spp. (36–79%). Concerning the nutritional indices, the atherogenicity index (AI) was between 0.4–3.2, the thrombogenicity index (TI) ranged from 0.04 to 1.95, except for Gracilaria spp., which had a TI of 7.6, and the hypocholesterolemic/hypercholesterolemic ratio (HH) values ranged between 0.88–4.21, except for Gracilaria spp., which exhibited values between 0.22–9.26. The n6/n3 ratio was below 1 for most of the species evaluated, except for Ascophyllum nodosum, which presented a higher value, although below 2. Considering the PUFA/SFA ratio, seaweeds presented values between 0.11–1.02. The polycyclic aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons (AHCs) contamination of seaweeds under study was also quantified, the values found being much lower than the maximum levels recommended for foodstuff.