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Background: The availability of soil phosphorus (P) often limits the productivities of wet tropical lowland forests. Little is known, however, about the metabolomic profile of different chemical P compounds with potentially different uses and about the cycling of P and their variability across space under different tree species in highly diverse tropical rainforests. Results: We hypothesised that the different strategies of the competing tree species to retranslocate, mineralise, mobilise, and take up P from the soil would promote distinct soil 31P profiles. We tested this hypothesis by performing a metabolomic analysis of the soils in two rainforests in French Guiana using 31P nuclear magnetic resonance (NMR). We analysed 31P NMR chemical shifts in soil solutions of model P compounds, including inorganic phosphates, orthophosphate mono- and diesters, phosphonates, and organic polyphosphates. The identity of the tree species (growing above the soil samples) explained > 53% of the total variance of the 31P NMR metabolomic profiles of the soils, suggesting species-specific ecological niches and/or species-specific interactions with the soil microbiome and soil trophic web structure and functionality determining the use and production of P compounds. Differences at regional and topographic levels also explained some part of the the total variance of the 31P NMR profiles, although less than the influence of the tree species. Multivariate analyses of soil 31P NMR metabolomics data indicated higher soil concentrations of P biomolecules involved in the active use of P (nucleic acids and molecules involved with energy and anabolism) in soils with lower concentrations of total soil P and higher concentrations of P-storing biomolecules in soils with higher concentrations of total P. Conclusions: The results strongly suggest "niches" of soil P profiles associated with physical gradients, mostly topographic position, and with the specific distribution of species along this gradient, which is associated with species-specific strategies of soil P mineralisation, mobilisation, use, and uptake. [ABSTRACT FROM AUTHOR]

Metabolomics is allowing great advances in biological sciences. Recently, an increasing number of ecological studies are using a metabolomic approach to answer ecological questions (ecometabolomics). Ecometabolomics is becoming a powerful tool which allows following the responses of the metabolome of an organism environmental changes and the comparison of populations. Some Nuclear Magnetic Resonance ( NMR) protocols have been published for metabolomics analyses oriented to other disciplines such as biomedicine, but there is a lack of a description of a detailed protocol applied to ecological studies., Here we propose a NMR-based protocol for ecometabolomic studies that provides an unbiased overview of the metabolome of an organism, including polar and nonpolar metabolites. This protocol is aimed to facilitate the analysis of many samples, as typically required in ecological studies. In addition to NMR fingerprinting, it identifies metabolites for generating metabolic profiles applying strategies of elucidation of small molecules typically used in natural-product research, and allowing the identification of secondary and unknown metabolites. We also provide a detailed description to obtain the numerical data from the 1H- NMR spectra needed to perform the statistical analyses., We tested and optimized this protocol by using two field plant species ( Erica multiflora and Quercus ilex) sampled once per season. Both species showed high levels of polar compounds such as sugars and amino acids during the spring, the growing season. E. multiflora was also experimentally submitted to drought and the NMR analyses were sensitive enough to detect some compounds related to the avoidance of water loses., This protocol has been designed for ecometabolomic studies. It identifies changes in the compositions of metabolites between individuals and detects and identifies biological markers associated with environmental changes. [ABSTRACT FROM AUTHOR]

Abstract: Ketoprofen is a nonsteroidal anti-inflammatory drug that has been detected in the environment in the range of ng L−1–μg L−1 due to its low degradability in some wastewater treatment plants. In this study, the use of the white-rot fungus Trametes versicolor to effectively degrade ketoprofen in a defined liquid medium was assessed. The fungus eliminated ketoprofen to nondetectable levels in 24h when it was added at 10mgL−1 whereas at low concentration of 40μgL−1 it was almost completely removed (95%) after 5h. Low extracellular laccase activity was detected in the T. versicolor cultures but the addition of the laccase-mediator system did not lead to ketoprofen oxidation. The cytochrome P-450 inhibitor 1-aminobenzotriazole reduced ketoprofen oxidation. These data suggest that the first oxidation step is cytochrome P450 mediated. During time-course degradation experiments, three intermediates were structurally elucidated and quantified by HPLC–DAD–MS and NMR: 2-[3-(4-hydroxybenzoyl)phenyl]-propanoic acid, 2-[(3-hydroxy(phenyl)methyl)phenyl]-propanoic acid, and 2-(3-benzoyl-4-hydroxyphenyl)-propanoic acid. The latter was reported for the first time in biological systems. After 7 d of incubation, only small amounts of 2-[(3-hydroxy(phenyl)methyl)phenyl]-propanoic acid (0.08mg) remained in the liquid medium in comparison with the initial ketoprofen dose (1.0mg), suggesting possible mineralization of ketoprofen. [Copyright &y& Elsevier]