We report the first biocatalytic modification of sesquiterpene lactones (STLs) found in the chicory plants, specifically lactucin (Lc), 11β,13-dihydrolactucin (DHLc), lactucopicrin (Lp), and ...11β,13-dihydrolactucopicrin (DHLp). The selective O-acylation of their primary alcohol group was carried out by the lipase B from Candida antarctica (CAL-B) using various aliphatic vinyl esters as acyl donors. Perillyl alcohol, a simpler monoterpenoid, served as a model to set up the desired O-acetylation reaction by comparing the use of acetic acid and vinyl acetate as acyl donors. Similar conditions were then applied to DHLc, where five novel ester chains were selectively introduced onto the primary alcohol group, with conversions going from >99 % (acetate and propionate) to 69 % (octanoate). The synthesis of the corresponding O-acetyl esters of Lc, Lp, and DHLp was also successfully achieved with near-quantitative conversion. Molecular docking simulations were then performed to elucidate the preferred enzyme-substrate binding modes in the acylation reactions with STLs, as well as to understand their interactions with crucial amino acid residues at the active site. Our methodology enables the selective O-acylation of the primary alcohol group in four different STLs, offering possibilities for synthesizing novel derivatives with significant potential applications in pharmaceuticals or as biocontrol agents.
Novel polystyrene‐based molecularly imprinted polymer nanofibers were synthesized through the electrospinning technique. The molecularly imprinted polymers were prepared using a non‐covalent approach ...and atrazine as template. For comparison, nonimprinted polymer nanofibers were also synthesized. The morphology of the synthesized nanofibers was characterized using scanning electron microscopy. The adsorption of pesticides, atrazine, atrazine desisopropyl, atraton, carboxin, linuron, and chlorpyrifos was studied under equilibrium (batch) conditions. To describe the adsorption capability of the synthesized polymers, Langmuir and Freundlich models were used. The Freundlich model provided a better mathematical approximation of the sorption characteristic for polymers nanofibers. To evaluate the adsorption capacity in the presence of interferents experiments on river water samples spiked with a mixture of six pesticides were also performed. The results obtained for the highest concentration levels investigated, show a greater amount of pesticide adsorbed on molecularly imprinted polymers and non‐imprinted polymers compared to those obtained using commercial stationary phases used as reference.
Recently, the cultivation of light Cannabis, with a total THC content less than 0.6%, has been encouraged due to its industrial and therapeutic potential. This has increased the consumption of hemp ...for both smoking purposes and food preparation. Even so, Cannabis inflorescences are not subject to EU regulations and standards provided for food and tobacco products. A study was carried out on thirty-one inflorescences samples, collected in different Italian regions, in order to determine cannabinoids, pesticides and metals and to evaluate the exposure of consumers to contaminants and ensure a safe consumption. Contents of THC were always below 0.5%, while CBD ranged between 0.3 and 8.64%. The determination of 154 pesticides showed that 87% of the samples contained fungicides and insecticides in the range 0.01–185 μg/g. The most found are spinosad and cyprodinil. The concentration of metals ranged from 1 to more than 100 μg/g and As, Cd, Co, Cr, Hg, Cu, Mo, Ni and V exceeded the regulatory US limits for inhaled Cannabis products, while Pb exceeded them for both oral and inhaled products. These contaminants are intrinsically toxic and may affect public health. Actions are needed to establish regulatory measures and reduce the adverse effects caused by contaminants in Cannabis.
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•Tetrahydrocannabinol (THC), cannabidiol (CBD), pesticides and metals were detected in light Cannabis inflorescences.•Pesticides, like fungicides and insecticides, were found in 87% of samples.•Metals showed levels exceeding the permissible limits in several samples.•The high concentrations of pesticides and metals represent a health risk for consumers.
BACKGROUND: Emerging evidence suggests a potential role for ubiquitous environmental contaminants in the physiopathology of endometriosis. Di‐(2‐ethylhexyl)‐phthalate (DEHP), the most commonly used ...plasticizer in flexible polyvinylchloride (PVC) formulations, is a widespread environmental contaminant with potentially adverse effects on fertility in animal models. In the present study, we tested the hypothesis that DEHP and/or and its main metabolite, mono‐ethylhexyl phthalate (MEHP), play a role in the pathogenesis of endometriosis. METHODS: Specimens of blood and peritoneal fluid were collected in a group of women with endometriosis (n = 55), and in age‐matched control women (n = 24). Concentrations of DEHP and MEHP were measured in plasma and peritoneal fluid by using high performance liquid chromatography (HPLC). Differences between groups were tested using the Fisher’s exact test, Wilcoxon‐test, and Kruskal–Wallis analysis of variance. RESULTS: Endometriotic women showed significantly higher plasma DEHP concentrations than controls (median 0.57 µg/ml, interquartile range: 0.06–1.23; values range: 0–3.24 versus median 0.18 µg/ml, interquartile range: 0–0.44; values range: 0–1.03; P = 0.0047) and 92.6% of them had detectable DEHP and /or MEHP in the peritoneal fluid. No significant differences in either the DEHP/MEHP plasma concentrations (P ≥ 0.31) or DEHP/MEHP peritoneal fluid concentrations (P ≥ 0.66) were observed in the endometriotic patients as a function of the disease stage at the time of diagnosis. CONCLUSIONS: The present findings showed for the first time an association between DEHP plasma concentrations and endometriosis, suggesting a possible role for phthalate esters in the pathogenesis.
Volcanic ashes from the Puna and surrounding Andean areas in northern Argentina show that sometimes volcanic ash deposits are very well preserved (up to several million years) and can remain a ...potential hazard for the environment in a similar way as current deposits. Eight ashes have been characterized by SEM–EDX and DRX, and their potential released geochemical fluxes were examined by using water and nitric acid batches, which are analyzed by ICP-OES, ICP-MS and ISE (F). Results demonstrate that water batch system is better medium than nitric acid for this study. The high and fast reactivity of these ancient ashes is mainly associated with their high content in glass. The order of magnitude of released contents of implied elements is consistent among the samples, i.e., Al
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B
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Fe
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Zn
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F
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P
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Mn
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Ba
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Sr
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Li
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Ti
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Rb
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Cu
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Ni
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Sb
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Pb
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As
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Cr
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V. Ash–water interaction, although infrequent in arid regions such as the Puna Region in northern Argentina, introduces rapid changes in the geochemical fluxes of elements and pH and may constitute a potential hazard for the environment. In fact, many of these elements are included in the drinking water guidelines due to their potential toxicity and may constitute potential hazards for the environment and human health.
The environmental geochemical behaviour of the rhyolitic ashes from the 2008 eruption of Chaitén volcano, Southern Chile, has been studied. After the bulk characterisation, the potential contribution ...to the regional geochemical fluxes was examined using: i) single batch leaching tests to provide a rapid screening of the implied major and trace elements; and ii) column experiments to evaluate the temporal mobility of leached elements. The environmental concerns of these ashes are related to the fine grained component present in each sample (independent of distance from the source), in particular the presence of cristobalite, and the geochemical hazards posed by ash–water interaction. Leaching experiments show the fast dissolution of surface salts and aerosols, which dominate over glass dissolution during the first steps of the ash–water interaction. Chaitén ashes could transfer to the environment more than 1×1010g or 10,000metric tonnes (mt) of Cl, S, Ca, Na, Si, and K; between 1000 and 10,000mt of F, Mg, and Al; between 100 and 1000mt of As, Pb, P, Fe, Sr, Zn, Mn, and Br; between 10 and 100mt of Ba, Li, Ti, Ni, Nb, Cu, Rb, Zr, V, Mo, Co, and Sc; and less than 10mt of Cr, Sb, Ce, Ga, Cs, and Y. These results show the fertilising potential of the ashes (e.g., providing Ca and Fe) but also the input of potentially toxic trace elements (e.g., F and As) in the regional geochemical mass balance. The Chaitén results evidence lower potentials for poisoning and fertilising than low silica ashes due to the lower contents released of practically all elements.
► We model the contribution of 2008 Chaitén ash to the regional geochemical balance. ► There are implied fertilising and potentially toxic elements. ► Chaitén could mobilise more than 10,000tonnes of Cl, S, Ca, Na, Si, and K to the environment. ► Leaching tests are a key tool for environmental monitoring of ash falls.
Parallel arrays of well aligned crack-free N-doped and undoped TiO2 nanofibers (3–4mm long, 300–500nm diameter) have been deposited by near field electrospinning (NFES) technique on Si3N4 substrates ...with interdigitated Pt electrodes and annealed at 400°C for 1h. Anatase TiO2 with crystallites’ size of approximately 12nm have been prepared and characterized by XRD, SEM, TEM and XPS techniques. Experimental measurements have been conducted through an ad hoc analog integrated resistive sensor interface, based on an oscillating circuit, fabricated in a 0.35μm standard CMOS technology. Gas response to NO2 in the range 1–10ppm and 100–300°C operating temperature (OT) has shown best practical sensor sensitivity (S=RG/RA) at a relatively low OT (150°C) and detection limits down to 1ppm gas. Nitrogen doping at N:Ti 1:1 atomic ratio has been proposed in order to decrease the intrinsic resistance of TiO2, thus enabling better signal to noise ratio of the electrical response.
Natural zeolitic rocks consisting mainly of chabazite-phillipsite, clinoptilolite, and volcanic glass have been evaluated by means of batch methods to remove arsenic from waters with different ...mineralization degree (from deionized water to natural water with a specific conductivity of 1,600 μS cm
−
1
). Arsenic was previously spiked in the studied waters at concentrations of about 100 µg l
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1
to simulate actual cases. The compositional range of natural waters is representative of large hydrogeochemical regions around the world. The experiments were focussed on the application of natural common zeolitic rocks to water treatment for human consumption. The removal efficiency observed rises, in the better cases, 60–80% for chabazite-phillipsite raw materials whereas is 40–60% for clinoptilolite-bearing ones. The arsenic removal tends to increase with water mineralization degree, independently of the zeolitic rock type. A large zeolitic content in the chabazite-phillipsite raw materials increase the removal. Instead, the inverse situation is observed in the clinoptilolite-bearing rocks. The relevance of the quantitative mineralogical analysis, determining also the content of volcanic glass, as well as the use of natural waters in the removal tests has been demonstrated.
During adolescence, there is an increased chance of increased incidence of depression and the development of addictive/dependent behaviours such as pathological gambling, excessive Internet use and ...compulsive shopping, Here we present a psychoeducational approach in the schools of Pescara and Penne to identify and treat these problems.
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