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A series of bis-indolone-N-oxides, 1a-f, was prepared from bis(ethynyl)benzenes and o-halonitroaryls and studied for their in vitro antiplasmodial activities against Plasmodium falciparum and representative strains of bacteria and candida as well as for their cytotoxicity against a human tumor cell line (MCF7). They did not cause any haemolysis (300 μgmL(-1)). Of the synthesized bis-indolones, compound 1a had the most potent antiplasmodial activity (IC50=0.763 μmolL(-1) on the FcB1 strain) with a selectivity index (CC50 MCF7/IC50 FcB1) of 35.6. No potency against the tested microbial strains was observed., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Toxicity and biotransformation of several earthworm contaminants are widely evaluated nowadays using biochemical biomarkers. Many investigations track enzyme activities as biomarkers of neurotoxicity (cholinesterase (ChE)), metabolisation (glutathione-S-transferase (GST)) and oxidative stress (catalase (CAT)). This study proposes an evaluation of the use of a combined buffer, to extract proteins from earthworms and then analyse the 3 biomarkers. The method provides good results and allows protein extraction and quantitative determination of biomarkers with the same efficiency as the enzyme-specific buffers. It decreases preparation time and permits a study of the biomarkers on the same individual with only one homogenisation.

A rapid and simultaneous method for residue identification and quantification for seven pesticides in agricultural soils has been developed to study a realistic situation in vineyard. The target compounds are two insecticides, two herbicides and three fungicides, from different chemical families. The procedure is based on a pressurized liquid extraction (PLE) with acetone, before a multiresidue GC-MS analysis. The recovery of PLE is between 53.8+/-2.4 and 99.9+/-4.4% according to pesticide. A limit of detection (LOD) between 1.4 and 4.6 microg kg(-1) of dry soil was obtained for five analytes. This procedure for testing soil contamination is sensitive and easy to perform.

A routine method which is simple, quick and precise has been set up and validated for phthalate analysis in environmental samples (tomato plants and sewage sludges). Six phthalates have been studied simultaneously: dimethylphthalate, diethylphthalate, di-n-butylphthalate, n-butylbenzylphthalate, di-2-ethyl-hexyl phthalate (DEHP) and di-n-octylphthalate. Optimization of sample, solvent extraction uses a Soxtec apparatus and extract purification with an a solid-phase extraction cartridge allows between 90 and 110% recovery of phthalates. Precise, sensitive and selective identification and quantifying of analytes is by GC-MS in the single ion monitoring mode. This protocol allows analytes with concentrations as low as 10 microg/kg dry matter (DM) to be determined from small (1-2 g DM) samples. This analytical method has been applied to the phthalate transfer study for agricultural recycling of sludges, where phthalate bioavailability has been studied in aquiculture using two types of experiments. Tomatoes have been grown in containers where the trace organics have been directly introduced as pure substances, and in a second experiment under the same growth conditions, sewage sludge has replaced the pure substances. Transfer of these trace organics has been followed into the various parts of the tomato plant and in general only the DEHP is worthy of note although its percentage transfer remains very low even in an experiment designed to maximize this.

For the purpose of this study, we used a "ball lens" UV laser-induced fluorescence (LIF) detector comprising a pulsed laser and a collinear optical arrangement. The fluorescence signal is induced by a pulsed laser and detected by a photomultiplier tube. When coupling the high-frequency pulsed laser to the LIF detector we used, the electronics which is designed for continuous wavelength (CW) lasers, "viewed" the laser as a continuous source. Despite this mismatch between the laser and the "ball lens" UV LIF detector, the sensitivity we obtained with tryptophan is comparable to the one obtained with the best "laboratory-made" detector described in the literature which used a CW UV laser. Limits of detection of 0.15 nM for tryptophan and 50 nM for tyrosine were estimated. As an application of this technology, we studied tryptophan and tyrosine in cerebrospinal fluids (CSFs). The analysis is very simple and works on very small samples (5 microl). It consists of using a 10 mM 3-cyclohexylamino-1-propanesulfonic acid, 15 mM sodium tetraborate, pH 9.2 buffer and injecting CSF diluted 20 times in water prior to injection. 5-Hydroxyindoleacetic acid was used as an internal standard. The separation is completed in less than 12 min. The capillary electrophoresis method which we chose is rapid, resolutive and allows accurate measurements. Recovery experiments in CSFs show recoveries between 97 and 102%. We investigated 14 different CSFs from patients who suffered from neurological disorders. Most of the concentrations vary in a range of 1.7 to 3.7 microM for Trp and 6.6 to 13.7 microM for Tyr, which is in the range observed in the literature. One patient who suffers from Huntington disease had a higher concentration of Tyr at 17.3 microM.