A method for digestion of soils with high inorganic matter content (ranging from 50 to 92%) by microwave-induced combustion (MIC) is proposed for the first time for further halogens (F, Cl, Br, and ...I) determination by ion chromatography (IC) and also by inductively coupled plasma mass spectrometry (ICP-MS). Microcrystalline cellulose (100–500 mg), used as a combustion aid, was mixed with sample and water or NH4OH solutions (10–100 mmol L–1) were investigated for analytes absorption. The use of cellulose (400 mg) was mandatory to volatilize the halogens from soils with high inorganic matter. It was possible to use diluted absorbing solutions (up to 100 mmol L–1 NH4OH) for halogens retention, providing limits of quantification in the range of 0.06 (I) to 60 (Cl) μg g–1. Accuracy was evaluated using certified reference materials (CRMs), spiked samples, and pyrohydrolysis method. Recoveries for halogens after spiked samples were in the range of 94 to 103% and the results after digestion of CRMs by MIC were in agreement better than 95% to certified values. Blanks were low, relative standard deviation was below 8% for all soils and no statistical difference was observed for results by pyrohydrolysis and MIC methods showing the feasibility of the proposed method for further halogens determination in soil samples.
Egg yolk constitutes a relevant alternative source of antibodies. It presents some advantages over mammalian serum immunoglobulins regarding productivity, animal welfare and specificity. The main ...immunoglobulin present in avian blood (IgY) is transmitted to their offspring and accumulates in egg yolks, which enables the non-invasive harvesting of high amounts of antibodies. Moreover, due to structural differences and phylogenetic distance, IgY is more suitable for diagnostic purposes than mammalian antibodies, since it does not react with certain components of the human immune system and displays greater avidity for mammalian conserved proteins. IgY has been extensively used in health researches, as both therapeutic and diagnostic tool. This article aims to review its applications in both human and veterinary health.
•IgY-technology is a new frontier for biological products•IgY Abs is a non-invasive technology obtained from egg yolks of immunized hens.•A wide range of IgY applications has been successfully tested in both human and animal health.•IgY technology constitutes a relevant alternative for the mammalian antibodies production.
This work evaluated the removal of a mixture of eight antibiotics (i.e. ampicillin (AMP), azithromycin (AZM), erythromycin (ERY), clarithromycin (CLA), ofloxacin (OFL), sulfamethoxazole (SMX), ...trimethoprim (TMP) and tetracycline (TC)) from urban wastewater, by ozonation operated in continuous mode at different hydraulic retention times (HRTs) (i.e. 10, 20, 40 and 60 min) and specific ozone doses (i.e. 0.125, 0.25, 0.50 and 0.75 gO3 gDOC− 1). As expected, the efficiency of ozonation was highly ozone dose- and contact time-dependent. The removal of the parent compounds of the selected antibiotics to levels below their detection limits was achieved with HRT of 40 min and specific ozone dose of 0.125 gO3 gDOC− 1. The effect of ozonation was also investigated at a microbiological and genomic level, by studying the efficiency of the process with respect to the inactivation of Escherichia coli and antibiotic-resistant E. coli, as well as to the reduction of the abundance of selected antibiotic resistance genes (ARGs). The inactivation of total cultivable E. coli was achieved under the experimental conditions of HRT 40 min and 0.25 gO3 gDOC−1, at which all antibiotic compounds were already degraded. The regrowth examinations revealed that higher ozone concentrations were required for the permanent inactivation of E. coli below the Limit of Quantification (<LOQ = 0.01 CFU mL− 1). Also, the abundance of the examined ARGs (intl1, aadA1, dfrA1, qacEΔ1 and sul1) was found to decrease with increasing HRT and ozone dose. Despite the fact that the mildest operating parameters were able to eliminate the parent compounds of the tested antibiotics in wastewater effluents, it was clearly demonstrated in this study that higher ozone doses were required in order to confer permanent damage and/or death and prevent potential post-treatment re-growth of both total bacteria and ARB, and to reduce the abundance of ARGs below the LOQ. Interestingly, the mineralization of wastewater, in terms of Dissolved Organic Carbon (DOC) removal, was found to be significantly low even when the higher ozone doses were applied, leading to an increased phytotoxicity towards various plant species. The findings of this study clearly underline the importance of properly optimising the ozonation process (e.g. specific ozone dose and contact time) taking into consideration both the bacterial species and associated ARGs, as well as the wastewater physicochemical properties (e.g. DOC), in order to mitigate the spread of ARB&ARGs, as well as to reduce the potential phytotoxicity.
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•The antibiotics examined were eliminated under the mildest operating conditions.•Total and antibiotic-resistant E. coli were inactivated after 40 min at low O3 dose.•The ARGs abundance was found to decrease with increasing contact time and O3 dose.•Mineralization was found to be significantly low.•Resulting phytotoxicity can be attributed to the dEfOM and its oxidation products.
•Plastic pellets act as a vector of additives and organic pollutants to the water column and interstitial water.•Leached chemicals from pellets reduce viability of sea urchin larvae.•Newly released ...pelletshave higher toxicitythan beach-stranded pellets.•The toxicity of stranded pellets depends on the exposure pathway (simulated leaching to interstitial water>water column).
Apart from the physiological impacts on marine organisms caused by ingesting microplastics, the toxicity caused by substances leaching from these particles into the environment requires investigation. To understand this potential risk, we evaluated the toxicity of virgin (raw) and beach-stranded plastic pellets to the development of embryos of Lytechinus variegatus, simulating transfers of chemical compounds to interstitial water and water column by assays of pellet–water interface and elutriate, respectively. Both assays showed that virgin pellets had toxic effects, increasing anomalous embryonic development by 58.1% and 66.5%, respectively. The toxicity of stranded pellets was lower than virgin pellets, and was observed only for pellet–water interface assay. These results show that (i) plastic pellets act as a vector of pollutants, especially for plastic additives found on virgin particles; and that (ii) the toxicity of leached chemicals from pellets depends on the exposure pathway and on the environmental compartment in which pellets accumulate.
A simple and automated system based on combustion followed by a pyrohydrolysis reaction was proposed for further halogens determination. This system was applied for digestion of soils containing high ...(90%) and also low (10%) organic matter content for further halogens determination. The following parameters were evaluated: sample mass, use of microcrystalline cellulose and heating time. For analytes absorption, a diluted alkaline solution (6 mL of 25 mmol L−1 NH4OH) was used in all experiments. Up to 400 mg of soil with high organic matter content and 100 mg of soil with low organic matter content (mixed with 400 mg of cellulose) could be completely digested using the proposed system. Quantitative results for all halogens were obtained using less than 12 min of sample preparation step (about 1.8 min for sample combustion and 10 min for pyrohydrolysis). The accuracy was evaluated using a certified reference material of coal and spiked samples. No statistical difference was observed between the certified values and results obtained by the proposed method. Additionally, the recoveries obtained using spiked samples were in the range of 98–103% with relative standard deviation values lower than 5%. The limits of quantification obtained for F, Cl, Br and I for soil with high (400 mg of soil) and low (100 mg of soil) organic matter were in the range of 0.01–2 μg g−1 and 0.07–59 μg g−1, respectively. The proposed system was considered as a simple and suitable alternative for soils digestion for further halogens determination by ion chromatography and inductively coupled plasma mass spectrometry techniques.
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•A simple and automated sample preparation system.•Combustion and pyrohydrolysis steps combined in the same system.•Volatilization of halogens using microcrystalline cellulose as a combustion aid.•The use of diluted solutions was compatible with both IC and ICP-MS analysis.•Halogens determination in soils containing variable organic matter.
The adsorption capacity of ciprofloxacin (CPX) was determined on three types of carbon-based materials: activated carbon (commercial sample), carbon nanotubes (commercial multi-walled carbon ...nanotubes) and carbon xerogel (prepared by the resorcinol/formaldehyde approach at pH 6.0). These materials were used as received/prepared and functionalised through oxidation with nitric acid. The oxidised materials were then heat treated under inert atmosphere (N2) at different temperatures (between 350 and 900°C). The obtained samples were characterised by adsorption of N2 at −196°C, determination of the point of zero charge and by temperature programmed desorption. High adsorption capacities ranging from approximately 60 to 300mgCPxgC−1 were obtained (for oxidised carbon xerogel, and oxidised thermally treated activated carbon Norit ROX 8.0, respectively). In general, it was found that the nitric acid treatment of samples has a detrimental effect in adsorption capacity, whereas thermal treatments, especially at 900°C after oxidation, enhance adsorption performance. This is due to the positive effect of the surface basicity. The kinetic curves obtained were fitted using 1st or 2nd order models, and the Langmuir and Freundlich models were used to describe the equilibrium isotherms obtained. The 2nd order and the Langmuir models, respectively, were shown to present the best fittings.
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►The adsorption capacity of ciprofloxacin was determined on carbon-based materials. ►Functionalised activated carbons, carbon nanotubes and carbon xerogels were compared. ►High adsorption capacities ranging from ∼60 to ∼300mgCPx/gC were obtained. ►The acid treatment is detrimental whereas thermal treatments enhance adsorption. ►Activated carbon treated at 900°C showed the best result due to the surface basicity.
The surface chemistry of a commercial AC (AC
0) was selectively modified, without changing significantly its textural properties, by chemical oxidation with HNO
3
(
AC
HNO
3
)
and O
2
(
AC
O
2
)
, ...and thermal treatments under H
2
(
AC
H
2
)
or N
2
(
AC
N
2
)
flow. The effect of modified AC on anaerobic chemical dye reduction was assayed with sulphide at different pH values 5, 7 and 9. Four dyes were tested: Acid Orange 7, Reactive Red 2, Mordant Yellow 10 and Direct Blue 71. Batch experiments with low amounts of AC (0.1
g
L
−1) demonstrated an increase of the first-order reduction rate constants, up to 9-fold, as compared with assays without AC. Optimum rates were obtained at pH 5 except for MY10, higher at pH 7. In general, rates increased with increasing the pH of point zero charge (pH
pzc), following the trend
AC
HNO
3
<
AC
O
2
<
AC
0
<
AC
N
2
<
AC
H
2
. The highest reduction rate was obtained for MY10 with
AC
H
2
at pH 7, which corresponded to the double, as compared with non-modified AC. In a biological system using granular biomass,
AC
H
2
also duplicated and increase 4.5-fold the decolourisation rates of MY10 and RR2, respectively. In this last experiment, reaction rate was independent of AC concentration in the tested range 0.1–0.6
g
L
−1.
Biomass burning in the Brazilian Amazon is modulated by climate factors, such as droughts, and by human factors, such as deforestation, and land management activities. The increase in forest fires ...during drought years has led to the hypothesis that fire activity decoupled from deforestation during the twenty-first century. However, assessment of the hypothesis relied on an incorrect active fire dataset, which led to an underestimation of the decreasing trend in fire activity and to an inflated rank for year 2015 in terms of active fire counts. The recent correction of that database warrants a reassessment of the relationships between deforestation and fire. Contrasting with earlier findings, we show that the exacerbating effect of drought on fire season severity did not increase from 2003 to 2015 and that the record-breaking dry conditions of 2015 had the least impact on fire season of all twenty-first century severe droughts. Overall, our results for the same period used in the study that originated the fire-deforestation decoupling hypothesis (2003-2015) show that decoupling was clearly weaker than initially proposed. Extension of the study period up to 2019, and novel analysis of trends in fire types and fire intensity strengthened this conclusion. Therefore, the role of deforestation as a driver of fire activity in the region should not be underestimated and must be taken into account when implementing measures to protect the Amazon forest.
In comparison with Ru
II
-arene compounds, the medicinal potential of homologous Ru
II
-tpm compounds tpm = tris(pyrazolyl)methane is underexplored. Pyridine, 4-pyridinemethanol and four ...functionalized pyridines, synthesized from the esterification of 4-pyridinemethanol with bioactive carboxylic acids (
i.e.
, ethacrynic acid, ibuprofen, flurbiprofen and naproxen), react with the precursor RuCl(κ
3
-tpm)(PPh
3
)
2
Cl (
1
) to afford RuCl(κ
3
-tpm)(PPh
3
)(L)Cl (
2-7
, L = pyridine ligand), in 78-91% yields. All products were fully characterized by HR-ESI mass spectrometry, IR and multinuclear NMR spectroscopy and the solid-state structures of two of the complexes,
i.e.
where L = pyridine and 4-pyridinemethanol, were ascertained by single crystal X-ray diffraction. The {Ru-tpm-PPh
3
} assembly is stable in D
2
O and in biological medium (DMEM) at 37 °C, with a tendency to slowly dissociate the pyridine ligand. The antiproliferative activity of the complexes was assessed on the cancerous A2780 and A2780cisR cell lines, and the nontumoral HEK 293T cell line; moreover inhibition assays were carried out on the complexes towards COX-2 and GSTP1 enzymes.
New anticancer Ru
II
-tpm complexes are presented, including a synthetic strategy to tether bioactive molecules to the metallic scaffold.
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