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- 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.
- 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.
- 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.
- Analysis of polycyclic aromatic hydrocarbons in fish: evaluation of a quick, easy, cheap, effective, rugged, and safe extraction methodPublication . Ramalhosa, Maria João; Paíga, Paula; Morais, Simone; Delerue-Matos, Cristina; Oliveira, M. Beatriz P. P.QuEChERS method was evaluated for extraction of 16 PAHs from fish samples. For a selective measurement of the compounds, extracts were analysed by LC with fluorescence detection. The overall analytical procedure was validated by systematic recovery experiments at three levels and by using the standard reference material SRM 2977 (mussel tissue). The targeted contaminants, except naphthalene and acenaphthene, were successfully extracted from SRM 2977 with recoveries ranging from 63.5–110.0% with variation coefficients not exceeding 8%. The optimum QuEChERS conditions were the following: 5 g of homogenised fish sample, 10 mL of ACN, agitation performed by vortex during 3 min. Quantification limits ranging from 0.12– 1.90 ng/g wet weight (0.30–4.70 µg/L) were obtained. The optimized methodology was applied to assess the safety concerning PAHs contents of horse mackerel (Trachurus trachurus), chub mackerel (Scomber japonicus), sardine (Sardina pilchardus) and farmed seabass (Dicentrarchus labrax). Although benzo(a)pyrene, the marker used for evaluating the carcinogenic risk of PAHs in food, was not detected in the analysed samples (89 individuals corresponding to 27 homogenized samples), the overall mean concentration ranged from 2.52 l 1.20 ng/g in horse mackerel to 14.6 ± 2.8 ng/ g in farmed seabass. Significant differences were found between the mean PAHs concentrations of the four groups.
- Commercial octopus species from different geographical origins: Levels of polycyclic aromatic hydrocarbons and potential health risks for consumersPublication . Oliveira, Marta; Gomes, Filipa; Torrinha, Álvaro; Ramalhosa, Maria João; Delerue-Matos, Cristina; Morais, SimonePolycyclic aromatic hydrocarbons (PAHs) are persistent pollutants that have been raising global concern due to their carcinogenic and mutagenic properties. A total of 18 PAHs (16 USEPA priority compounds, benzo(j)fluoranthene and dibenzo(a,l)pyrene) were assessed in the edible tissues of raw octopus (Octopus vulgaris, Octopus maya, and Eledone cirrhosa) from six geographical origins available to Portuguese consumers. Inter- and intra-species comparison was statistically performed. The concentrations of total PAHs (∑PAHs) ranged between 8.59 and 12.8 μg/kg w.w. Octopus vulgaris caught in northwest Atlantic Ocean presented ΣPAHs significantly higher than those captured in Pacific Ocean and Mediterranean Sea, as well as than the other characterized species from western central and northeast Atlantic Ocean. PAHs with 2-3 rings were the predominant compounds (86-92% of ∑PAHs) but diagnostic ratios indicated the existence of pyrogenic sources in addition to petrogenic sources. Known and possible/probable carcinogenic compounds represented 11-21% of ΣPAHs. World and Portuguese per capita ingestion of ∑PAHs due to cephalopods consumption varied between 1.62-2.55 × 10-4 and 7.09-11.2 × 10-4 μg/kg body weight per day, respectively. Potential risks estimated for low and high consumers according to USEPA methodology suggested that a regular consumption of raw octopus does not pose public health risks.
- Honey as an Adjuvant in the Treatment of COVID-19 Infection: A ReviewPublication . Soares, Sónia; Bornet, Mélina; Grosso, Clara; Ramalhosa, Maria João; Gouvinhas, Irene; Garcia, Juliana; Rodrigues, Francisca; Delerue-Matos, CristinaSince ancestor times, honey has been used to promote human health due to its medicinal, and nutritious properties, mainly due to bioactive compounds present, such as phenolic compounds. The emergence of COVID-19, caused by the SARS-CoV-2 virus, led to the pursuit of solutions for the treatment of symptoms and/or disease. Honey has proven to be effective against viral infections, principally due to its potential antioxidant and anti-inflammatory activities that attenuate oxidative damage induced by pathogens, and by improving the immune system. Therefore, the aim of this review is to overview the abilities of honey to attenuate different COVID-19 symptoms, highlighting the mechanisms associated with these actions and relating the with the different bioactive compounds present. A brief, detailed approach to SARS-CoV-2 mechanism of action is first overviewed to allow readers a deep understanding. Additionally, the compounds and beneficial properties of honey, and its previously application in other similar diseases, are detailed in depth. Despite the already reported efficacy of honey against different viruses and their complications, further studies are urgently needed to explain the molecular mechanisms of activity against COVID-19 and, most importantly, clinical trials enrolling COVID-19 patients.
- Analysis of polycyclic aromatic hydrocarbons in fish: optimisation and validation of microwave-assisted extractionPublication . Ramalhosa, Maria João; Paíga, Paula; Morais, Simone; Sousa, Ana M. M.; Gonçalves, Maria Pilar; Delerue-Matos, Cristina; Oliveira, M. Beatriz P. P.An accurate and sensitive method for determination of 18 polycyclic aromatic hydrocarbons (PAHs) (16 PAHs considered by USEPA as priority pollutants, dibenzo[a,l]pyrene and benzo[j]fluoranthene) in fish samples was validated. Analysis was performed by microwave-assisted extraction and liquid chromatography with photodiode array and fluorescence detection. Response surface methodology was used to find the optimal extraction parameters. Validation of the overall methodology was performed by spiking assays at four levels and using SRM 2977. Quantification limits ranging from 0.15–27.16 ng/g wet weight were obtained. The established method was applied in edible tissues of three commonly consumed and commercially valuable fish species (sardine, chub mackerel and horse mackerel) originated from Atlantic Ocean. Variable levels of naphthalene (1.03–2.95 ng/g wet weight), fluorene (0.34–1.09 ng/g wet weight) and phenanthrene (0.34–3.54 ng/g wet weight) were detected in the analysed samples. None of the samples contained detectable amounts of benzo[a]pyrene, the marker used for evaluating the occurrence and carcinogenic effects of PAHs in food.
- Seasonal and Spatial Comparison of Polycyclic Aromatic Hydrocarbons Among Decapod Shrimp from Coastal PortugalPublication . Maia, Maria Luz; Paíga, Paula; Ramalhosa, Maria João; Delerue-Matos, Cristina; Calhau, Conceição; Domingues, ValentinaPolycyclic aromatic hydrocarbons (PAHs) are ubiquitous global pollutants that are lipophilic, bioaccumulative and can be both endocrine disruptors and carcinogens. In this study, we measured 18 PAHs among decapod shrimp samples (Palaemon spp.) collected during the spring and autumn from multiple locations along the Portuguese coastal, including local markets and aquaculture farms. ΣPAH concentrations in samples ranged from 3.14 to 320.48 ng/g (ww) with the highest value in this range detected in a sample provided from an aquaculture facility. Fifteen of the 18 scanned PAHs were present in shrimp samples. However, detectable concentrations (0.07 ng/g ww) of the carcinogenic benzo-a-pyrene occurred for a single sample only and approached method detection limits. No significant differences in shrimp ΣPAH concentrations were evident between the spring and autumn seasons. Target hazard quotient estimation suggested low probability of adverse health effects to consumers through consumption of shrimp from the study collection locations.
- Assessment of groundwater contamination in an agricultural peri-urban area (NW Portugal): an integrated approachPublication . Barroso, M. Fátima; Ramalhosa, Maria João; Olhero, A.; Antão, M. C.; Pina, M. F.; Guimarães, L.; Teixeira, J.; Afonso, M. J.; Delerue-Matos, Cristina; Chaminé, Helder I.The excessive use of pesticides and fertilisers in agriculture has generated a decrease in groundwater and surface water quality in many regions of the EU, constituting a hazard for human health and the environment. Besides, on-site sewage disposal is an important source of groundwater contamination in urban and peri-urban areas. The assessment of groundwater vulnerability to contamination is an important tool to fulfil the demands of EU Directives. The purpose of this study is to assess the groundwater vulnerability to contamination related mainly to agricultural activities in a peri-urban area (Vila do Conde, NW Portugal). The hydrogeological framework is characterised mainly by fissured granitic basement and sedimentary cover. Water samples were collected and analysed for temperature, pH, electrical conductivity, chloride, phosphate, nitrate and nitrite. An evaluation of groundwater vulnerability to contamination was applied (GOD-S, Pesticide DRASTIC-Fm, SINTACS and SI) and the potential nitrate contamination risk was assessed, both on a hydrogeological GIS-based mapping. A principal component analysis was performed to characterised patterns of relationship among groundwater contamination, vulnerability, and the hydrogeological setting assessed. Levels of nitrate above legislation limits were detected in 75 % of the samples analysed. Alluvia units showed the highest nitrate concentrations and also the highest vulnerability and risk. Nitrate contamination is a serious problem affecting groundwater, particularly shallow aquifers, especially due to agriculture activities, livestock and cesspools. GIS-based cartography provided an accurate way to improve knowledge on water circulation models and global functioning of local aquifer systems. Finally, this study highlights the adequacy of an integrated approach, combining hydrogeochemical data, vulnerability assessments and multivariate analysis, to understand groundwater processes in peri-urban areas.
- Development of New Canned Chub Mackerel Products Incorporating Edible Seaweeds—Influence on the Minerals and Trace Elements CompositionPublication . Vieira, Elsa F.; Soares, Cristina; Machado, Susana; Oliva-Teles, MT; Correia, Manuela; Ramalhosa, Maria João; Carvalho, A.; Domingues, Valentina; Antunes, Filipa; Morais, Simone; Delerue-Matos, CristinaThis study aimed to develop new canned chub mackerel products incorporating edible seaweeds (Ascophyllum nodosum, Fucus spiralis, Saccorhiza polyschides, Chondrus crispus, Porphyra sp. and Ulva sp.) harvested in the Portuguese North-Central coast, with simultaneous sensory improvement and minerals enrichment. Two processes were compared, namely the addition of seaweeds in i) the canning step and ii) in the brining step (as the replacement for salt). The concentrations of four macrominerals (Na, K, Ca and Mg), chloride, and twelve trace elements (Co, Cu, Fe, I, Li, Mn, Mo, Rb, Se, Sr, V and Zn) were determined by high-resolution continuum source flame atomic absorption spectrometry (HR-CS-FAAS) and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Results showed that canned chub mackerel incorporating C. crispus and F. spiralis was found to be the preferred sensory option, also exhibiting contents enriched with Cl, Co, Cu, Fe, I, Li, Mg, Mn, Mo, Na, Rb, Se, and Sr. This effect was more pronounced when both seaweed species were added to replace the salt added in the brining step.
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