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1.
Adv Exp Med Biol ; 1357: 43-82, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35583640

RESUMO

The extensive knowledge in the miniemulsion technique used in biocatalysis applications by the authors allowed the development of drug delivery systems that constitutes the LipNanoCar technology core for the production of lipid nanoemulsions and solid lipid nanoparticles. The LipNanoCar technology, together with adequate formulations of different oils, fatty acids, surfactants, and temperature, allows the entrapment of several bioactive and therapeutic compounds in lipid nanoparticles for cosmetic, nutrition, and pharmaceutical applications.The LIpNanoCar technology allowed lipid nanoparticles production with average sizes ranging from 100 to 300 nm and Zeta Potentials between -55 and -20 mV. Concomitantly, high entrapment or encapsulation efficiencies (%EE) were achieved, as illustrated in this work for ß-carotene and vitamins derivatives (>85%) for cosmetic application, and for antibiotics currently used in chemotherapy, like rifampicin (69-85%) and pyrazinamide (14-29%) against Mycobacterium tuberculosis (TB), and ciprofloxacin (>65%) and tobramycin (~100%) in Cystic Fibrosis (CF) respiratory infections therapy. Ciprofloxacin presented, for example, a quick-release from the lipid nanoparticles using a dialysis tubing (96% in the first 7 h), but slower than the free antibiotic (95% in the first 3 h). This result suggests that ciprofloxacin is loaded near the external surface of the lipid nanoparticles.The toxicity and validation of entrapment of antibiotics in lipid nanoparticles for Cystic Fibrosis therapy were assessed using Caenorhabditis elegans as an animal model of bacterial infection. Fluorescence microscopy of an entrapped fluorescent dye (DiOC) confirmed the uptake of the lipid nanoparticles by ingestion, and their efficacy was successfully tested in C. elegans. Burkholderia contaminans IST408 and Burkholderia cenocepacia K56-2 infections were tested as model bacterial pathogens difficult to eradicate in Cystic Fibrosis respiratory diseases.


Assuntos
Fibrose Cística , Nanopartículas , Infecções por Pseudomonas , Animais , Antibacterianos/uso terapêutico , Caenorhabditis elegans , Ciprofloxacina/uso terapêutico , Fibrose Cística/microbiologia , Lipossomos , Infecções por Pseudomonas/tratamento farmacológico , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa , Tecnologia
2.
Mar Environ Res ; 190: 106064, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37344267

RESUMO

Mola mola is the largest teleost inhabiting our ocean and the presence of microplastics (MP) in this flagship species was, before this study, never described. Thus, this investigation focused on analysing MP ingestion in 53 ocean giant sunfish in the Northeast Atlantic Ocean. A total of 116 MP were found in 79% of the specimens, with a median of 1 MP.ind-1, ranging from 0 to 11 MP.ind-1. Seasonal differences were observed, with more fibers registered in specimens caught in autumn. Among the different size classes observed, the smallest category (<300 µm) was the most frequent (43%). Blue (43%) was the most prevalent color, followed by green (29%) and black (10%). The majority of fragments were styrene acrylic copolymer (53%), while most fibers were rayon (78%). These findings emphasize that the ocean sunfish population crossing the southern waters of Portugal is exposed to microplastic pollution and highlight the need for effective management policies to address plastic pollution in marine ecosystems.


Assuntos
Tetraodontiformes , Poluentes Químicos da Água , Animais , Plásticos , Microplásticos , Ecossistema , Oceano Atlântico , Ingestão de Alimentos , Monitoramento Ambiental
3.
Sci Total Environ ; 856(Pt 2): 159077, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36181822

RESUMO

Microplastics (<5 mm) are a ubiquitous marine pollutant which are highly bioavailable to marine organisms across all trophic levels. Marine predators are especially vulnerable to microplastic pollution through direct and indirect ingestion (e.g., trophic transfer) due to their high trophic position. In particular, oceanic islands are more susceptible to plastic accumulation, increasing the relative number of microplastics in the environment that are available for consumption. The dynamics of microplastic accumulation in marine predators inhabiting remote islands, however, is sparsely documented. Here we describe microplastic exposure in the Critically Endangered Mediterranean monk seal (Monachus monachus) from the Madeira archipelago (Northeast Atlantic) using scat-based analysis. Microplastics were recovered from 18 scat samples collected between 2014-2021 and were characterized to the polymer level using Fourier-Transform Infrared (u-FTIR) spectroscopy. A total of 390 microplastic particles were recovered, ranging between 0.2-8.6 particles g-1 dry weight (mean 1.84 ± 2.14 particles g-1) consisting mainly of fragments (69 %) of various sizes and polymer composition (e.g., PE, PET, PS). Microplastic prevalence (100 % of samples analysed) was higher than what has been previously recorded using scat-based analysis in other pinniped species. Our results suggest that the levels of microplastic pollution in the coastal food-web in the Madeira archipelago are relatively high, placing higher-trophic level organisms at increased risk of microplastic consumption, including humans. This study provides the first insights into microplastic exposure to Madeira's monk seals that may contribute to future management decisions for the species and their long-term survival.


Assuntos
Focas Verdadeiras , Poluentes Químicos da Água , Animais , Humanos , Microplásticos , Plásticos/análise , Cadeia Alimentar , Polímeros , Poluentes Químicos da Água/análise , Monitoramento Ambiental
4.
Mar Pollut Bull ; 181: 113911, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35816821

RESUMO

Potassium hydroxide (KOH) digestion protocols are currently applied to separate microplastics from biological samples, allowing efficient digestion with minor degradation of polymers in a time- and cost-effective way. For biota samples with high-fat content, KOH reacts with triglycerides generating an overlying soap layer, making difficult the digestion and solubilization and subsequent microplastics extraction. Here we studied the addition of Tween-20 in different concentrations to evaluate the effect on the soap layer of post-digested samples. Addition of 10 % of Tween-20 presented higher flow rate during filtration, being set as optimal value. Incorporation of Tween-20 in the extraction procedure increased recovery rates of LDPE, PC and PET and appears to have a protective effect on PC and PET degradation. Tween-20 did not interfere in FTIR spectrum of polymers available in the marine environment. Being low-toxic, makes addition of Tween-20 a simple and economical way to optimize KOH digestion protocols for microplastics extraction.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Monitoramento Ambiental/métodos , Trato Gastrointestinal/química , Plásticos/metabolismo , Polímeros , Polissorbatos , Sabões , Poluentes Químicos da Água/análise
5.
Mar Pollut Bull ; 173(Pt A): 113008, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34653887

RESUMO

Wild fish (Cyprinus carpio, Mugil cephalus, Platichthys flesus) from an estuary of the NE Atlantic coast were investigated for plastic contamination (N = 128). From the 1289 particles recovered from fish samples, 883 were plastics. Among these, 84% were fibres and 97% were microplastics. Thirty-six polymers were identified. The number of microplastics (mean ± SD) per individual fish (MP/fish) was 8 ± 6 in C. carpio, 10 ± 9 in M. cephalus and 2 ± 2 in P. flesus. The means of MP/fish per body site were 6 ± 7 in gastrointestinal tract, 0.5 ± 1.1 in gills, 0.3 ± 0.7 in liver and 0.6 ± 1.2 in muscle samples. A few large fibres in liver (≤ 4841 µm) and muscle (≤ 5810 µm) samples were found. The results evidence the existence of high fish contamination by microplastics and reinforce the need of further research on plastic pollution in estuaries.


Assuntos
Carpas , Poluentes Químicos da Água , Animais , Oceano Atlântico , Monitoramento Ambiental , Estuários , Peixes , Microplásticos , Plásticos , Rios , Poluentes Químicos da Água/análise
6.
Environ Sci Pollut Res Int ; 27(21): 26643-26649, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32378098

RESUMO

Microplastics are widely recognized as a category of emergent pollutants that can cause complex ecotoxicological effects. Synthetic fibers released during the washing of textiles are a relevant source of microplastics, which reach aquatic ecosystems from sewer discharges, even when there is retention in wastewater treatment plants. In this paper, we determined microfiber emissions from washing of textiles in a domestic environment, by collecting wastewater from washings of a mix of clothing from a household of 4 people. It is the first time the characterization of microplastic emission from textiles washing is performed in real household conditions. Results estimated an average emission rate of 18,000,000 synthetic microfibers for a reference load of 6 kg of synthetic fibers. Only 7% of the synthetic fibers found were larger than 500 µm in length, 40% were between 100 and 500 µm, and 53% were between 50 and 100 µm.


Assuntos
Águas Residuárias , Poluentes Químicos da Água/análise , Ecossistema , Monitoramento Ambiental , Microplásticos , Plásticos , Têxteis
7.
Sci Total Environ ; 717: 134625, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-31836230

RESUMO

Microplastics (MP) pollution has received increased attention over the last few years. However, while the number of studies documentating the ingestion of microplastics by fish has increased, fewer studies have addressed the toxicological effects derived from the ingestion of these small items in wild conditions. Here, MP contamination and effect biomarkers were investigated in three commercially important fish species from the North East Atlantic Ocean. From the 150 analysed fish (50 per species), 49 % had MP. In fish from the 3 species, MP in the gastrointestinal tract, gills and dorsal muscle were found. Fish with MP had significantly (p ≤ 0.05) higher lipid peroxidation levels in the brain, gills and dorsal muscle, and increased brain acetylcholinesterase activity than fish where no MP were found. These results suggest lipid oxidative damage in gills and muscle, and neurotoxicity through lipid oxidative damage and acetylcholinesterase induction in relation to MP and/or MP-associated chemicals exposure. From the 150 fish analysed, 32 % had MP in dorsal muscle, with a total mean (± SD) of 0.054 ± 0.099 MP items/g. Based on this mean and on EFSA recommendation for fish consumption by adults or the general population, human consumers of Dicentrachus labrax, Trachurus trachurus, Scomber colias may intake 842 MP items/year from fish consumption only. Based on the mean of MP in fish muscle and data (EUMOFA, NOAA) of fish consumption per capita in selected European and American countries, the estimated intake of microplastics through fish consumption ranged from 518 to 3078 MP items/year/capita. Considering that fish consumption is only one of the routes of human exposure to microplastics, this study and others in the literature emphasize the need for more research, risk assessment and adoption of measures to minimize human exposure to these particles. Thus, MP pollution and its effects should be further investigated and addressed according to the WHO 'One Health' approach.


Assuntos
Peixes , Animais , Oceano Atlântico , Ingestão de Alimentos , Monitoramento Ambiental , Humanos , Lipídeos , Microplásticos , Oxirredução , Estresse Oxidativo , Poluentes Químicos da Água
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