Identification and characterization of phenolic compounds in hydromethanolic extracts of sorghum wholegrains by LC-ESI-MSn

Hydromethanolic extracts of brown, red, and white sorghum whole grains were analysed by LC-MSn in negative ESI mode within the range m/z 150–550 amu. Besides the flavonoids already reported in sorghum, a number of flavonoids were also identified in the sorghum grain for the first time, including flavanones, flavonols and flavanonols, and flavan-3-ol derivatives. Various phenylpropane glycerides were also found in the sorghum grain, the majority of them are reported here for the first time, and a few of them were detected with abundant peaks in the extracts, indicating they are another important class of phenolic compounds in sorghum. In addition, phenolamides were also found in sorghum grain, which have not been reported before, and dicaffeoyl spermidine was detected in high abundance in the extracts of all three type sorghum grains. These results confirmed that sorghum is a rich source of various phenolic compounds

Fluoxetine accumulation and metabolism as exposure biomarker to better understand biological effects in gastropods

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Utilisation du POCIS pour 56 composés organiques polaires - cinétiques d'accumulation, taux d'échantillonnage et identification de 6 PRC

International audiencePOCIS (Polar Organic Chemical Integrative Sampler) is a new emerging tool for sampling polar organic micropollutants in water. There is still a need of research concerning its domain of validity (e.g., molecules sampled, type of water studied, optimal exposure duration) and its performances (molecules sampling rates, repeatability, accuracy of the evaluation of time-weighted average or TWA concentrations). In order to obtain in situ TWA concentrations, POCIS needs to be calibrated in laboratory for each molecule of interest. We performed 3 different laboratory calibration experiments using a flow-through calibration system in order to evaluate the optimal exposure duration and to calculate the sampling rates for 56 polar organic contaminants, and to identify and validate performance reference compounds (PRCs). The calibration system was composed of 2 aquaria (50 L) containing i) spiked tap water (circa 3 µg/L) and non-spiked POCIS for the determination of accumulation kinetics, ii) non-spiked tap water and spiked POCIS for the determination of desorption kinetics and iii) spiked tap water and spiked POCIS for the validation of the potential PRCs. In all experiments, water temperature, pH, conductivity and dissolved organic carbon were controlled. Agitation in the aquaria was ensured via a submerged pump. The resulting flow velocity was 105 cm/s and was directed perpendicularly towards POCIS surface. Triplicate POCIS were analyzed at 0, 1, 3, 6 and 12 hours and at 1, 3, 7, 11, 14, 21 and 28 days. We present results for the 56 studied molecules, including the duration of linear accumulation phase, sampling rates and possible performance reference compounds (PRCs). The accumulation phase was curvilinear for almost all molecules; so, we obtained the duration of optimal linear accumulation phase using t1/2 criteria. Concerning the desorption experiments, 5 compounds showed a good potential as PRC; they enable to decrease the effect of variable environmental conditions, so they can be used to obtain more reliable in situ TWA concentrations. We also checked isotropic exchange for these molecules comparing the exchange constant ke in accumulation and desorption experiments. At last, we validated the PRC strategy by calculating TWA concentrations from the third laboratory experiment mentioned above

Détermination des cinétiques d'accumulation et des taux d'échantillonnages pour 56 micropolluants organiques polaires et évaluation de 5 PRC potentiels avec le POCIS "pharmaceutiques"

International audiencePOCIS (Polar Organic Chemical Integrative Sampler) is a recent integrative sampler made for sampling polar organic micropollutants in water. It is still in development concerning its domain of validity (e.g., molecules sampled, type of water studied, optimal exposure duration) and its performances (molecules sampling rates, repeatability, accuracy of the evaluation of time-weighted average concentrations - TWAC). In order to obtain in situ TWAC, POCIS needs to be calibrated in laboratory for each molecule of interest. In this work, we performed laboratory calibration of POCIS for 5 alkylphenols, 9 hormones, 11 pesticides, 27 pharmaceuticals, 3 phenols and 1 UV filter in a flow-through system. The system is composed of 2 aquaria (50 L) containing: i) spiked tap water (circa 3 µg/L for each studied molecule) and non-spiked POCIS, for the determination of accumulation kinetics or ii) non-spiked tap water and spiked POCIS, for the determination of desorption kinetics. We present results for the different studied molecules, including the duration of linear accumulation phase, sampling rates and possible performance reference compounds (PRCs). The accumulation phase was curvilinear for almost all molecules; so, we obtained the duration of optimal linear accumulation phase using t1/2 criteria. Concerning the desorption experiments, 5 compounds showed a good potential as PRC; they enable to decrease the effect of variable environmental conditions, so they can be used to obtain more reliable TWAC in situ. At last, we checked isotropic exchange for these molecules comparing the exchange constant ke in accumulation and desorption experiments

Accumulation et metabolisation de la fluoxétine. Biomarqueur d'exposition pour la compréhension des effets biologiques chez des gastéropodes

International audienceFluoxetine is a widely used antidepressant frequently found in wastewater treatment plant effluent and in aquatic ecosystems at concentrations below μg/L. Numerous studies have explored the sensitivity of invertebrates to waterborne fluoxetine showing marked differences of sensitivity. In a previous study, the New-Zealand mudsnail, Potamopyrgus antipodarum, and the European valve snail, Valvata piscinalis, were exposed to waterborne fluoxetine (3.7-100 μg/L) during 42 days. While effects were observed on the mudsnail reproduction and F1, the valve snail was not affected. Several assumptions were proposed to explain these results including dissimilar metabolic capacities or bioavailability of fluoxetine for the snails. The aim of this study was to asses if differential sensitivity of gastropods snails to fluoxetine could be explained by its bioaccumulation and metabolism into norfluoxetine

Surveillance de polluants émergents dans des eaux de surface. Calibration de 25 perturbateurs endocriniens et de 17 pharmaceutiques avec le POCIS et le Chemcatcher et détermination de PRC potentiels

International audienceIn response to the increase of the number of organic pollutants identified in surface waters, multi-residue analytical strategies using concentration steps have been used for the analysis of grab water samples. Recently, integrative sampling systems more realistic of environmental exposition have been designed to measure mean concentrations of xenobiotics and to estimate their toxicological effects on the environment and on human health. The ability to use two integrative samplers for the monitoring of endocrine disruptors and pharmaceuticals has been evaluated. Polar Organic Chemical Integrative Samplers (POCIS) in “Pharmaceutical” configuration and Chemcatcher with C18 SPE disks and diffusion membrane have been rigorously calibrated for 43 organic pollutants. Samplers have been exposed for 28 days in a 50 L tank with continuous renewal of spiked solutions. Performance Reference Compounds (PRCs) have also been investigated. To our knowledge, this is the first comparison performed for more than 40 molecules between POCIS and Chemcatcher with 3 potential PRCs proposed for each sampler. Most of the compounds of interest accumulate with a relatively good linearity (R² from 0.90 to 0.99) for 21 to 28 days on POCIS. Chemcatcher also gave acceptable accumulation linearity (R²>0.90) but reached equilibrium more rapidly than POCIS (11 to 14 days depending on molecules). Sampling rates calculated for POCIS (0.03 to 0.29 L/d) are often higher than for Chemcatcher (0.01 to 0.25 L/d). 3 molecules per sampler showed relatively good exponential correlations during the desorption study: R2 from 0.89 to 0.96 for POCIS and from 0.95 to 0.99 for Chemcatcher. A second calibration study reinforced data for the behaviour of samplers between 0 and 11 days of exposure and confirmed the ability to use the 6 molecules proposed as potential PRCs

L'apport de la spectrométrie de masse haute-résolution à l'obtention d'empreintes moléculaires d'échantillons d'urine. Applications potentielles au dopage.

National audienc

Study of a large scale powdered activated carbon pilot: Removals of a wide range of emerging and priority micropollutants from wastewater treatment plant effluents

International audienceThe efficacy of a fluidized powdered activated carbon (PAC) pilot (CarboPlus®) was studied in both nominal (total nitrification + post denitrification) and degraded (partial nitrification + no denitrification) configuration of the Seine Centre WWTP (Colombes, France). In addition to conventional wastewater parameters 54 pharmaceuticals and hormones (PhPHs) and 59 other emerging pollutants were monitored in influents and effluents of the pilot. Thus, the impacts of the WWTP configuration, the process operation and the physico-chemical properties of the studied compounds were assessed in this article.Among the 26 PhPHs quantified in nominal WWTP configuration influents, 8 have high dissolved concentrations (>100 ng/L), 11 have an intermediary concentration (10–100 ng/L) and 7 are quantified below 10 ng/L. Sulfamethoxazole is predominant (about 30% of the sum of the PhPHs). Overall, 6 PhPHs are poorly to moderately removed (80%), i.e. beta blockers, carbamazepine or trimethoprim, and 11 are well eliminated (60–80%), i.e. diclofenac, naproxen or sulfamethoxazole.In degraded WWTP configuration, higher levels of organic matter and higher concentrations of most pollutants are observed. Consequently, most PhPHs are substantially less removed in percentages but the removed flux is higher. Thus, the PAC dose required to achieve a given removal percentage is higher in degraded WWTP configuration. For the other micropollutants (34 quantified), artificial sweeteners and phthalates are found at particularly high concentrations in degraded WWTP configuration influents, up to μg/L range. Only pesticides, bisphenol A and parabens are largely eliminated (50–95%), while perfluorinated acids, PAHs, triclosan and sweeteners are not or weakly removed (<50%). The remaining compounds exhibit a very variable fate from campaign to campaign.The fresh PAC dose was identified as the most influencing operation parameter and is strongly correlated to performances. Charge and hydrophobicity of compounds have been recognized as crucial for the micropollutant adsorption on PAC, as well as the molecular weight. Finally, a PAC dose of 10 mg/L allows an average removal of 72–80% of the sum of the PhPHs in nominal WWTP configuration. The comparaison of the results with those from the scarce other studies tends to indicate that an extrapolation of them to different PAC processes and to other WWTPs could be possible and relevant, taking into account the differences of water quality from WWTP to WWTP