•Nineteen seaweeds were screened for antioxidant and α-glucosidase inhibitory activity.•Active extracts investigated by high-resolution α-glucosidase inhibition profiling.•HPLC–HRMS–SPE–NMR used for ...structure elucidation of α-glucosidase inhibitors.•α-Glucosidase inhibitory activity caused by phlorotannins as well as fatty acids.•Oleic-, linoleic- and eicosapentaenoic acid showed IC50 of 0.069, 0.075 and 0.10mM.
Crude chloroform, ethanol and acetone extracts of nineteen seaweed species were screened for their antioxidant and α-glucosidase inhibitory activity. Samples showing more than 60% α-glucosidase inhibitory activity, at a concentration of 1mg/ml, were furthermore investigated using high-resolution α-glucosidase inhibition profiling combined with high-performance liquid chromatography–high-resolution mass spectrometry–solid-phase extraction–nuclear magnetic resonance spectroscopy (HR-bioassay/HPLC–HRMS–SPE–NMR). The results showed Ascophyllum nodosum and Fucus vesicolosus to be rich in antioxidants, equaling a Trolox equivalent antioxidant capacity of 135 and 108mMTroloxmg−1 extract, respectively. HR-bioassay/HPLC–HRMS–SPE–NMR showed the α-glucosidase inhibitory activity of A. nodosum, F. vesoculosus, Laminaria digitata, Laminaria japonica and Undaria pinnatifida to be caused by phlorotannins as well as fatty acids – with oleic acid, linoleic acid and eicosapentaenoic acid being the most potent with IC50 values of 0.069, 0.075 and 0.10mM, respectively, and showing a mixed-type inhibition mode.
► Enhanced performance was attributed to high surface area and desorption of hydroxy. ► Optimum condition was found at the mass ratio of iridium to tin was 2:1. ► Terminal voltage of water ...electrolysis was 1.70
V at 80
°C and 2
A
cm
−2.
Electrocatalysts made of IrO
2/SnO
2 were prepared using the Adams method for solid polymer electrolyte (SPE) water electrolysis. The physicochemical properties of the catalyst were characterized via X-ray diffraction (XRD) and transmission electron microscopy (TEM). The electrochemical properties of the catalyst were investigated using cyclic voltammetry (CV), electrochemical impendence spectroscopy (EIS), chronopotentiometry and Tafel curve measurements in 0.1
mol
L
−1 H
2SO
4 at room temperature. The test results showed that the catalytic properties of IrO
2/SnO
2 depended on the mass ratio of iridium to tin, and that the optimal mass ratio was 2:1. The optimized catalyst was applied to a membrane electrode assembly (MEA), and the stationary current–potential relationships were determined. With an IrO
2/SnO
2 (2:1) anode, a 40% Pt/C cathode and a total noble metal (Ir, Pt) loading of 1.2
mg
cm
−2, the terminal applied potential difference of the water electrolysis was 1.70
V at 2
A
cm
−2 and 80
°C.
Acrylamide (AA) is a process-contaminant formed during Maillard Reaction (MR) in starchy foods heated at temperatures above 120 °C. It has been classified by the International Agency for Research on ...Cancer (IARC) as a probable carcinogen (2A) and genotoxic substance. Detecting AA in a reliable, rapid, cost-effective, and sustainable manner is crucial. This article reviews the most commonly used techniques for extracting and quantifying AA in various food samples, while also discussing the latest innovative techniques and future trends in AA analysis. In recent years, innovative extraction methods have been developed to improve selectivity for AA compared to traditional techniques that require Internal Standards (IS) and highly sensitive quantification methods. This is particularly important due to the complex nature of food matrices. The critical step in AA quantification lies in purifying the aqueous extract because AA is highly soluble in water and coexists with other polar compounds. Innovative solvent-free techniques offer advantages such as improved selectivity, efficiency, and cost-effectiveness. They can also reduce the need for extensive sample preparation and minimize the interference of other compounds present in the food matrices. In addition, modified QuEChERS extraction techniques have been proposed, which involve a significant reformulation of the commonly used methods. As research in this field continues to evolve, it is expected that future trends will focus on further improving the accuracy, sensitivity and sustainability of AA detection, ultimately contributing to food safety and consumer health.
•Purification of aqueous extract is a critical point for acrylamide determination.•Internal standard and highly sensitive detection techniques, such as mass spectrometry are necessary.•Dummy Molecularly Imprinted Polymers or Accelerated Solvent Extraction are innovative, selective and environmentally sustainable techniques.•Dummy Molecularly Imprinted Polymers or Accelerated Solvent Extraction can avoid or minimize the use of organic solvents.
The migration of plastic components or additives from packaging to food can produce a risk for human health, in fact many of these plasticizers and additives are “Endocrine Distruptors”, such as ...phthalates (PAEs), alkylphenols (APs), 2,2-bis(4-hydroxyphenyl)propane (bisphenol A or BPA) and di(2-ethylhexyl)adipate (DEHA). The evaluation of some PAEs, some APs, BPA and DEHA levels in common food packaging (oil and natural tuna cans, marmalade cap, yogurt packaging, polystyrene dish, teat, bread bag, film, baby's bottle, aseptic plastic laminate paperboard carton and plastic wine top) was carried out by migration tests. Furthermore to evaluate the potential migration of plasticizers and additives from plastic wine tops, two extraction methods were used, one through incubation at 40 °C for 10 days and one by ultrasounds extraction. The simulants employed were distilled water, acetic acid at 3%, ethanol at 15% for wine top. The food simulant was extracted by solid phase extraction (SPE) and analyzed by GC–MS. Comparing these results with EU restrictions all samples showed contaminant migration lower than SML and OML established. Finally, about the comparison of two extraction methods, the extraction carried out for 10 days at 40 °C may be better than the other one in order to detect all compounds.
► PAEs, APs, BPA and DEHA levels were investigated in common packaging. ► These levels were considered in synthetic wine tops by two extraction methods. ► Migration tests were carried out as suggested by the Directive 85/572/CEE and 82/711/EC. ► All samples contained at least one contaminant but at levels lower than EU restriction. ► The extraction by extreme condition was better than other.
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•A novel portable microscale SPE device (μSPE) was developed for LPS extraction.•μSPE utilized small sample amount for sensitive and selective detection in CE-LIF.•μSPE was able to ...extract KP-LPS efficiently with high average recovery rate of 98%.•The enrichment of KP-LPS with μSPE was achieved by 23 times preconcentration.•μSPE was successfully applied on water samples with LPS concentration in ng mL−1.
Lipopolysaccharides (LPS), also known as endotoxins, can be released into the environment when the bacteria’s cell wall breaks apart, which induces inflammatory responses in humans at amounts of 1–10 ng kg−1. This paper reports on the development and optimization of a novel analytical method for the analysis of LPS based on the coupled use of a laboratory–made microscale solid-phase extraction (μSPE) device for the purification and enrichment of LPS before fluorescent dye derivatization and lastly capillary electrophoresis with laser-induced fluorescence (CE-LIF) for separation and detection. In this work, the limits of detection and quantification of Klebsiella pneumoniae (KP)-LPS were found to reach 1.32 ng mL−1 and 4.39 ng mL−1, respectively with a linear dynamic range of 0.125–0.625 mg L−1 and a relative standard deviation of 0.9% in migration time. Scanning electron microscopy analysis clearly supports the successful entrapment of KP-LPS within the sorbent before elution. In contrast to other LPS extraction methods, the optimized μSPE-based method coupled with CE-LIF provides the following advantages: small sample amount for sensitive and selective detection in CE-LIF (μSPE preconcentration factor of 23 times), reduced volumes of organic solvents used (175–225 µL), high recovery rate of 98%, as well as portability for on-site extraction and quantification of analytes. The method was successfully applied in the analysis of three types of real water samples (i.e. deionized water, secondary effluent and raw sewage). Raw sewage was found to contain the highest KP-LPS amount of 12.5 ng mL−1 followed by secondary effluent of 7.3 ng mL−1.
An analytical method based on an optimized solid‐phase extraction procedure and followed by high‐performance liquid chromatography (HPLC) separation with diode array detection was developed and ...validated for the simultaneous determination of phenolic acids (gallic, protocatechuic, 4‐hydroxy‐benzoic, vanillic, caffeic, syringic, p‐coumaric, ferulic, sinapic, and cinnamic acids), flavanols (catechin and epicatechin), flavonols (myricetin, quercetin, kaempferol, quercetin‐3‐O‐glucoside, hyperoside, and rutin), flavones (luteolin and apigenin) and flavanones (naringenin and hesperidin) in rice flour (Oryza sativa L.). Chromatographic separation was carried out on a PerfectSil Target ODS‐3 (250 mm × 4.6 mm, 3 μm) column at temperature 25°C using a mobile phase, consisting of 0.5% (v/v) acetic acid in water, methanol, and acetonitrile at a flow rate 1 mL min−1, under gradient elution conditions. Application of optimum extraction conditions, elaborated on both Lichrolut C18 and Oasis HLB cartridges, have led to extraction of phenolic acids and flavonoids from rice flour with mean recoveries 84.3–113.0%. The developed method was validated in terms of linearity, accuracy, precision, stability, and sensitivity. Repeatability (n = 5) and inter‐day precision (n = 4) revealed relative standard deviation (RSD) <13%. The optimized method was successfully applied to the analysis of phenolic acids and flavonoids in pigmented (red and black rice) and non‐pigmented rice (brown rice) samples.
Our study focuses on enhancing the antioxidant potential of saffron petals extract (SPE) as a sustainable corrosion inhibitor for aluminium (Al) in a 3.5% NaCl solution. The phytochemical screening ...and antioxidant activity are identified. Various investigative methodologies, including experimental techniques such as Electrochemical Impedance Spectroscopy (EIS) and Potentiodynamic Polarization (PDP), were employed to evaluate the effectiveness of this compound in inhibiting corrosion. Computational analysis, involving Density Functional Theory (DFT) and Molecular Dynamics (MD) simulations, were utilized to carry out a Theoretical study on the main constituents of SPE. The surface characteristics and composition of the corroded Al were examined using a combination of Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDX) and Fourier Transform Infrared Spectroscopy (FT-IR). The Electrochemical results suggest that the effectiveness of the inhibitor was dependent on its concentration, reaching 95.11% at 500 ppm of SPE. The PDP indicates that mixed inhibition control effectively slowed down the corrosion of Al. Furthermore, the adsorption behaviour of SPE onto Al follows to the Langmuir isotherm model. SEM, EDX and FT-IR analyses further verified significant alterations in the surface morphology and roughness of Al and confirming the successful formation of a protective layer on the Al surface. Ultraviolet-Visible spectroscopy (UV-Vis) reveals evidence of interaction between Al and the SPE molecules. Computational studies substantiated these observations, demonstrating the reactivity and adsorption patterns of the evaluated major bioactive molecules of SPE on the Al surface.
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•The experimental results confirmed the inhibition efficiency of SPE.•SPE demonstrated exceptional inhibitory performance over 24 hours of immersion.•SEM and FT-IR confirmed the formation of a protective layer by SPE and Al cations.•MD and DFT offered valuable insights into the adsorption of some SPE's molecules.
Lunar regolith simulant is exposed to a fast neutron flux of a spallation source. The samples consisted of a set of as-received, traditionally sintered, and solar sintered JSC-2A lunar regolith ...simulant. Aluminium samples were also irradiated for comparison. The ChipIr beamline of the ISIS neutron and muon source was used to provide a flux of atmospheric-like neutrons. The shielding properties of the different samples were measured for transmission, by counting neutrons before and after the samples using fast neutron detectors. Monte-Carlo simulations were carried out concurrently. The simulations are in good agreement with measurements. Aluminium simulations have shown to be in better accordance with the experimental results, probably because less affected by systematic errors. As for regolith shielding, a sensitivity analysis showed the low impact of the variations in regolith composition on the shielding properties. The benchmark of the simulations has allowed an independent estimate of the required level of regolith shielding needed to cope with primary and secondary radiation emissions. For galactic cosmic rays a value > 200 g/cm2 is estimated to give >50% reduction in transmission. For solar particle events a few 10s of g/cm2 can reduce the dose by more than an order of magnitude.
•Lunar regolith simulants were exposed to a fast neutron flux.•Monte-Carlo simulations were carried out concurrently.•Shielding capability of lunar regolith were measured and discussed.•For GCRs a value > 200 g/cm2 is estimated to give >50% reduction in transmission.•For SPE a few 10s of g/cm2 can reduce the dose by more than an order of magnitude.
The use of a variety of antibiotics in fish farming raises serious concern about the development of antibiotic resistance. Sulfonamides antibiotics (SAs), which are widely used in aquaculture and ...generate large eco‒toxicological effects with significant mutagenicity and teratogenic consequences, are still difficult to determine in aquatic organisms. In this study, an automatic technology was developed by coupling on‒line solid phase extraction system (on‒line SPE) with ultra‒high‒performance liquid chromatography spectrometry‒mass spectrometry (UHPLC‒MS/MS). Particularly, using a single on‒line column in the process of sample pretreatment, e.g., HLB or C18, phospholipids that potentially caused the matrix effect cannot be removed form biological sample. We applied a mixed cation exchange column (Oasis® MCX) connected with a hydrophilic lipophilic balance column (Oasis® HLB) in series in on‒line SPE clean‒up to remove interferences and finally obtained a clear and stable eluant. The on‒line SPE working conditions and UHPLC‒MS/MS parameters were optimized for their sensitivity, accuracy, decision limit, and detection capability, which were further calibrated for fish, shrimp and crab. The results showed that the limits of detection and limits of quantification ranged from 1.46 to 15.5 ng/kg, and 4.90–51.6 ng/kg, respectively. Accuracy values covered 71.5%–102% at the three concentration levels (0.1, 0.5, 1.0 μg/kg) for all compounds and average repeatability (relative standard deviation, RSD%) ranged from 3.47% to 14.2%. This on‒line SPE coupled with UHPLC‒MS/MS method is a way forward for an automatic, powerful detection technology for determination of antibiotics from complex matrix.
•A method for determination of sulfonamides in aquatic organisms was developed.•The quantitative method was based on on-line SPE-UHPLC-MS/MS technology.•On-line SPE clean-up consisted of two SPE columns connected in series.•Method validation was according to the European Union Decision 2002/657/EC.•Antibiotics concentrations were determined in fish, shrimp and crab.
