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1.
Foods ; 13(9)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38731668

RESUMO

A high consumption of solid fats is linked to increased inflammation and a risk of cardiovascular diseases. Hence, in recent years, there has been increasing interest in the development of oleogels as a fat substitute in food products. Oleogels are edible gels that contain a large amount of liquid oils entrapped in a 3D network and that can potentially be applied to spreads, bakery goods, meat, and dairy products in order to lower their saturated fat content while maintaining a desirable food texture and mouthfeel. In this work, alginate cryogels were studied as templates for three different edible oils in the process of oleogel formation. Two different freezing regimes to obtain cryogels were employed in order to evaluate better the textural and morphological capabilities of cryogels to adsorb and retain edible oils. It was shown that rapid freezing in liquid nitrogen produces alginate cryogels with a lower density, higher porosity, and a greater ability to adsorb the tested oils. The highest uptake and holding oil capacity was achieved for olive oil, which reached a value of 792% and 82%, respectively. The best chewiness was found for an oleogel containing olive oil, whereas oleogels with the other two tested oils showed better springiness. Hence, the results presented in this work demonstrated that alginate-based cryogels can be effectively used as templates for oleogels and potentially find applications in the food industry.

2.
Water Sci Technol ; 77(1-2): 439-447, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29377828

RESUMO

Evaluation of the bioavailable fractions of organic contaminants such as polycyclic aromatic hydrocarbons (PAHs) is extremely important for assessing their risk to the environment. This available fraction, which can be solubilised and/or easily extracted, is believed to be the most accessible for bioaccumulation, biosorption and/or transformation. Sediment organic matter (OM) and clay play an important role in the biodegradation and bioavailability of PAHs. The strong association of PAHs with OM and clay in sediments has a great influence not only on their distribution but also on their long-term environmental impact. This paper investigates correlations between bioavailability and the clay and OM contents in sediments. The results show that OM is a better sorbent for pyrene (chosen as a model PAH) and that increasing the OM content reduces the bioavailable fraction. A mathematical model was used to predict the kinetic desorption, and these results showed that the sediment with the lowest content of OM had an Ffast value of 24%, whereas sediment with 20% OM gave a value of 9%. In the experiments with sediments with different clay contents, no clear dependence between clay and rate constants of the fast desorbing fractions was observed, which can be explained by the numerous possible interactions at the molecular level.


Assuntos
Silicatos de Alumínio/química , Sedimentos Geológicos/química , Substâncias Húmicas/análise , Modelos Teóricos , Pirenos/análise , Poluentes Químicos da Água/análise , Adsorção , Biodegradação Ambiental , Disponibilidade Biológica , Argila
3.
Water Environ Res ; 89(7): 663-671, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-28641675

RESUMO

In this study, solar cells were used to generate an electric field for the electrokinetic remediation of metal contaminated sediment (Nickel, Cadmium, Zinc). For determination of metals mobility, bioavailability and potential toxicity, sequential extraction procedure, simultaneously extracted metals (SEM) and acid-volatile sulphide ratios (AVS) were performed before, during and after treatment.After 21 days of treatment, 63% Ni, 82% Cd and 58% Zn was removed from the anode region. The application of the electric field changed the chemical composition of the sediments. The risk assessment analysis based on pseudo total metals content, the risk assessment code and the relationship between SEM and AVS, indicates that a simple singular approach for risk assessment analysis and evaluation of the quality of sediments is not enough.


Assuntos
Técnicas Eletroquímicas , Poluentes Ambientais/química , Sedimentos Geológicos , Metais/química , Energia Solar
4.
Environ Sci Pollut Res Int ; 24(9): 8458-8468, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28188553

RESUMO

The wastewater canal Vojlovica of the Pancevo industrial area, Serbia, is the main collector of the effluents from the local industrial complex. The canal is directly connected to the Europe's second largest river, the Danube. Here, we present a chemical and microbiological analysis of the sediment in order to determine the fate of pollutants over the years, as well as its current condition. Dry matter, clay and organic matter content, a Kjeldahl ammonia, phosphorus, metals, and polychlorinated biphenyls as well as polycyclic aromatic hydrocarbons concentrations were measured. Microbiological analysis included heterotrophic and oil-degrading bacterial counts, isolation of the phenanthrene-degrading bacteria, and identification of cyanobacteria. Generally, in comparison to the results from previous studies, concentrations of the measured pollutants have been in a decline. Specifically, the metal and polycyclic aromatic hydrocarbon concentrations were reduced whereas microbial counts and toxicity tests did not indicate significant pollution. The obtained results are probably a consequence of an improved wastewater treatment and microbial degradation of pollutants.


Assuntos
Sedimentos Geológicos/química , Águas Residuárias , Monitoramento Ambiental , Hidrocarbonetos Policíclicos Aromáticos , Rios/química , Sérvia , Poluentes Químicos da Água
5.
Environ Sci Pollut Res Int ; 23(4): 3239-46, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26490893

RESUMO

Large amounts of sediment are dredged globally every year. This sediment is often contaminated with low concentrations of metals, polycyclic aromatic hydrocarbons, pesticides and other organic pollutants. Some of this sediment is disposed of on land, creating a need for risk assessment of the sediment disposal method, to minimize the degradation of environmental quality and prevent risks to human health. Evaluating the available fractions of certain polycyclic aromatic hydrocarbons is very important, as in the presence of various organisms, they are believed to be easily subject to the processes of bioaccumulation, biosorption and transformation. In order to determine the applicability of applying these methods for the evaluation of pollutant bioavailability in sediments, the desorption kinetics from the sediment of various polycyclic aromatic hydrocarbons in the presence of Tenax and XAD4 were examined over the course of 216 h. Changes in the PAH concentrations in dredged sediments using five different seed plants during a short time of period (10 days) were also followed. Using chemical extraction techniques with Tenax and XAD4, a time of around 24 h is enough to achieve equilibrium for all four PAHs. Results showed good agreement between the seed accumulation and PAH extraction methods with both agents. If we compare the two extraction techniques, XAD4 gave better results for phenanthrene, pyrene and benzo(a)pyrene, and Tenax gave better results for chrysene.


Assuntos
Sedimentos Geológicos/química , Plantas/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Adsorção , Disponibilidade Biológica , Germinação/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/química , Polímeros , Poliestirenos , Polivinil
6.
J Hazard Mater ; 283: 60-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25261761

RESUMO

This work compares the biodegradation potential of four polycyclic aromatic hydrocarbons (PAH) (phenanthrene, pyrene, chrysene and benzo(a)pyrene, chosen as representatives of the 3, 4 and 5 ring PAHs) with their desorption from sediment by XAD4 resin and methyl-ß-cyclodextrin (MCD). The biodegradation study was conducted under various conditions (biostimulation, bioaugmentation and their combination). The results show that total PAH removal in all treatments except biostimulation gave similar results, whereby the total amount of PAHs was decreased by about 30-35%. The desorption experiment showed that XAD4 desorbed a greater fraction of phenanthrene (77% versus 52%), and benzo(a)pyrene (44% versus 25%) than MCD. The results for four ring PAHs were similar for both desorption agents (about 30%). Comparing the maximum biodegraded amount of each PAH with the rapidly desorbed XAD4 and MCD fraction, XAD4 was found to correlate better with biodegradation for the high molecular PAHs (pyrene, chrysene, benzo(a)pyrene), although it overestimated the availability of phenanthrene. In contrast, MCD showed better correlation with the biodegradation of low molecular weight PAHs.


Assuntos
Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Poliestirenos/química , Polivinil/química , beta-Ciclodextrinas/química , Bactérias/isolamento & purificação , Bactérias/metabolismo , Biodegradação Ambiental , Disponibilidade Biológica , Modelos Químicos , Microbiologia da Água , Poluentes Químicos da Água/análise
7.
Psychosom Med ; 71(6): 607-14, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19553287

RESUMO

OBJECTIVE: To examine associations of maternal lifetime trauma and related psychological symptoms in the perinatal period with infant cardiorespiratory reactivity and behavioral distress in response to a laboratory stressor, using a novel advanced system recently adapted for infants. METHODS: Participants were mothers and their 6-month-old infants. Assessments included mothers' self-reported lifetime exposure to trauma, perinatal traumatic stress, and current symptoms of posttraumatic stress disorder (PTSD) and depression. Through the use of a noninvasive respiratory inductance plethysmography device, heart rate and indices of respiratory volume, timing, and thoracoabdominal coordination were recorded continuously in 23 infants during the Still-Face Paradigm, a videotaped mother-infant dyadic assessment that included baseline, stressor, and recovery phases. Infant behavioral distress during the procedure was also assessed. RESULTS: Infants of mothers with low exposure to trauma and perinatal traumatic stress showed expected increases in behavioral distress and cardiorespiratory activation from baseline to stressor and decreases in these parameters from stressor to recovery. Infants of mothers exposed to multiple traumas and with elevated perinatal traumatic stress showed similar patterns of activation from baseline to stressor but failed to show decreases during recovery. These patterns were maintained after controlling for current maternal PTSD and depressive symptoms. CONCLUSIONS: Maternal lifetime trauma exposure and traumatic stress during the perinatal period were associated with disrupted infant cardiorespiratory regulation and behavioral distress during a stressor protocol. These results support the concept of perinatal programming and its potential role in physical and mental health outcomes.


Assuntos
Comportamento do Lactente/fisiologia , Acontecimentos que Mudam a Vida , Mães/psicologia , Complicações na Gravidez/epidemiologia , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Estresse Psicológico/epidemiologia , Depressão Pós-Parto/epidemiologia , Depressão Pós-Parto/psicologia , Desenho de Equipamento , Feminino , Frequência Cardíaca/fisiologia , Humanos , Lactente , Comportamento do Lactente/psicologia , Comportamento Materno/psicologia , Exposição Materna , Monitorização Fisiológica , Relações Mãe-Filho , Pletismografia/instrumentação , Gravidez , Complicações na Gravidez/psicologia , Testes de Função Respiratória , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Gravação de Videoteipe
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