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Pentadesma butyracea is a medicinal plant of which bark decoctions are used in traditional medicine for the treatment of diarrhea symptoms in Gabon. The aim of the present work was to perform phytochemical and pharmacological analyses of decoctions of P. butyracea bark. In a principal approach, spectrophotometric analyses were used to quantify phenolic compounds, followed by liquid chromatography coupled to mass spectrometry analysis that allowed the identification of flavanone–flavone dimers as the main metabolites. Pharmacological analyses showed the absence of toxicity, thus confirming the safety of use of this decoction in traditional medicine. The antioxidant activity of the bark decoctions was demonstrated to depend on their phenolic contents. The decoction of stem barks harvested during the rainy season also induced a dose-dependent relaxation of isolated ileum fragments from Wistar rats. In addition, the antidiarrheal activity of P. butyracea barks was investigated against castor oil-induced diarrhea. The oral administration of different concentrations of this decoction led to a decrease in wet stools, indicating an antidiarrheal effect at the doses that were used. These results encourage the deepening of bio-guided research on P. butyracea bark decoctions in order to propose standard traditional medical treatments. [ABSTRACT FROM AUTHOR]

Immature citruses are an important resource for the pharmaceutical industry due to their high levels of metabolites with health benefits. In this study, we used untargeted liquid chromatography–mass spectrometry (LC-MS) metabolomics to investigate the changes associated with fruit size in immature citrus fruits in the first weeks of growth. Three orange cultivars (Citrus sinensis 'Navel', Citrus sinensis 'Valencia', and Citrus sinensis 'Valencia Late') and a mandarin (Citrus reticulata Blanco 'Fremont') were separated into eight fruit sizes, extracted, and analyzed. Statistical analyses revealed a distinct separation between the mandarin and the oranges based on 56 metabolites, with an additional separation between the 'Navel' orange and the 'Valencia' and 'Valencia Late' oranges based on 21 metabolites. Then, metabolites that evolved significantly with fruit size growth were identified, including 40 up-regulated and 31 down-regulated metabolites. This study provides new insights into the metabolite modifications of immature Citrus sinensis and Citrus reticulata in the first weeks of growth and emphasizes the significance of including early sampled fruits in citrus maturation studies. [ABSTRACT FROM AUTHOR]

The composition of dissolved organic matter of cloud water has been investigated through non-targeted high-resolution mass spectrometry on only a few samples that were mostly collected in the Northern Hemisphere in the USA, Europe and China. There remains, therefore, a lack of measurements for clouds located in the Southern Hemisphere, under tropical conditions and influenced by forest emissions. As a matter of fact, the comparison of the composition of clouds collected in different locations is challenging since the methodology for the analysis and data treatment is not standardized. In this work, the chemical composition of three samples collected at Réunion Island (REU) during the BIO-MAÏDO field campaign, in the Indian Ocean, with influences from marine, anthropogenic and biogenic (tropical) emissions, is investigated and compared to the chemical composition of samples collected at the Puy de Dôme (PUY) observatory in France. The same methodology of analysis and data treatment was employed, producing a unique dataset for the investigation of the molecular composition of organic matter in cloud water. Besides the analysis of elemental composition, we investigated the carbon oxidation state (OSC) of dissolved organic matter, finding that overall samples collected at PUY are more oxidized than those collected at REU. Molecular formulas were also classified based on stoichiometric elemental ratios, showing the high frequency and abundance of reduced organic compounds, classified as lipids (LipidC), in this matrix, which led to a search for terpene oxidation products in cloud water samples. To better discriminate between samples collected at PUY and REU, statistical analysis (principal component analysis and agglomerative hierarchical clustering) was performed on the ensemble of molecular formulas and their intensities. Samples collected at REU have a different composition from samples collected at PUY, which is mainly linked to different primary sources, the processing of organic matter in cloud water and the influence of different primary emissions at the two locations. [ABSTRACT FROM AUTHOR]

The composition of cloud water dissolved organic matter has been investigated through non-targeted high resolution mass spectrometry only on few samples, mostly collected in the Northern hemisphere, in USA, Europe and China. Nevertheless, there is a lack of measurements for clouds located in the Southern Hemisphere, under tropical conditions and influenced by forest emissions. Moreover, the comparison of the composition of cloud samples collected in different locations is not trivial, since the methodology for the analysis and data treatment are not standardized. In this work, the chemical composition of three samples collected at Reunion Island (REU) during the BIO-MAÏDO field campaign, in the Indian Ocean, with influences from marine, anthropogenic and biogenic (tropical) emissions is investigated and compared to the chemical composition of samples collected at the puy de Dôme (PUY) observatory, in France. The same methodology of analysis and data treatment was employed, producing a unique dataset for the investigation of molecular composition of organic matter in cloud water. Besides the analysis of elemental composition, we investigated the carbon oxidation state (OSC) of dissolved organic matter, finding that overall samples collected at PUY are more oxidized than those collected at REU. Molecular formulas were also classified based on stoichiometric elemental ratios, showing the high frequency and abundance of reduced organic compounds, classified as lipids (LipidC), in this matrix, which led to search for terpenes oxidation products in cloud water samples. To better discriminate between samples collected at PUY and at REU, statistical analysis (principal component analysis and agglomerative hierarchical clustering) was performed on the ensemble of molecular formulas and their intensities. Samples collected at REU, have a different composition from samples collected at PUY, mainly linked to the processing of organic matter in cloud water, but also to the influence of different primary emissions at the two locations. [ABSTRACT FROM AUTHOR]

As part of a project funded by the European Commission (EC) for the development and evaluation of multiresidue methods for analysis of drinking and related waters, 17 European laboratories evaluated a method using styrene-divinylbenzene copolymer solid-phase extraction followed by liquid chromatography with diode array detection. The main aim of the study was to evaluate whether the method meets the requirements of EC Drinking Water Directive 98/83 in terms of accuracy, precision, and detection limit for 21 pesticides according to the following requirements: limit of detection, < or =0.025 microg/L; accuracy expressed as recovery, between 75 and 125%; and precision expressed as repeatability relative standard deviation of the method, <12.5%, and as reproducibility relative standard deviation of the method, <25%. Analyses for unknown concentrations were performed with commercial bottled and tap waters. All laboratories were able to achieve detection limits of 0.01 microg/L for all pesticides except pirimicarb (0.02 microg/L). The criteria for repeatability were met for all compounds. Terbutryn in bottled water and carbendazim in tap water did not meet the criteria for reproducibility. In terms of accuracy, the method met the requirements for all pesticides in both matrixes, except for metamitron. However, several compounds (linuron, terbutryn, propazine, metobromuron, and isoproturon) showed recoveries slightly below 75%.