Continental scale deciphering of microbiome networks untangles the phyllosphere homeostasis in tea plant.

Introduction: Assembly and co-occurrence of the host co-evolved microbiota are essential ecological and evolutionary processes, which is not only crucial for managing individual plant fitness but also ecological function. However, understanding of the microbiome assembly and co-occurrence in higher plants is not well understood. The tea plant was shown to contribute the forest fitness due to the microbiome assembled in the phyllosphere; the landscape of microbiome assembly in the tea plants and its potential implication on phyllosphere homestasis still remains untangled.

Supercritical fluid chromatography-tandem mass spectrometry-assisted methodology for rapid enantiomeric analysis of fenbuconazole and its chiral metabolites in fruits, vegetables, cereals, and soil.

Here, we developed a rapid and robust supercritical fluid chromatography-tandem mass spectrometry (SFC-MS/MS) method for simultaneous detection of fenbuconazole and its chiral metabolites in fruit, vegetable, cereal, and soil. Baseline separation of six stereoisomers was achieved on an amylose tris-(3,5-dimethylphenylcarbamate)-coated chiral column in 4.0min using a mobile phase composed of CO/ethanol (flow rate of 1.

Conditions Optimizing and Application of Laccase-mediator System (LMS) for the Laccase-catalyzed Pesticide Degradation.

A high capacity of laccase from Trametes versicolor capable of degrading pesticides has been revealed. The conditions for degrading of five selected pesticides including chlorpyrifos, chlorothalonil, pyrimethanil, atrazine and isoproturon with the purified laccases from Trametes versicolor were optimized. The results showed that the optimum conditions for the highest activity were pH at 5.

Solid-phase extraction combined with dispersive liquid-liquid microextraction for the determination of pyrethroid pesticides in wheat and maize samples.

A rapid, selective and sensitive sample preparation method based on solid-phase extraction combined with the dispersive liquid-liquid microextration was developed for the determination of pyrethroid pesticides in wheat and maize samples. Initially, the samples were extracted with acetonitrile and water solution followed phase separation with the salt addition. The following sample preparation involves a solid-phase extraction and dispersive liquid-liquid microextraction step, which effectively provide cleanup and enrichment effects.

Response surface methodology for the enantioseparation of dinotefuran and its chiral metabolite in bee products and environmental samples by supercritical fluid chromatography/tandem mass spectrometry.

Tracing the enantiomers of dinotefuran and its metabolite in bee products and relevant environmental matrices is vital because of the high toxicity of their racemates to bees. In this study, a statistical optimization strategy using three-dimensional response surface methodology for the enantioseparation of dinotefuran and its metabolite UF was developed by a novel supercritical fluid chromatography/tandem mass spectrometry (SFC-MS/MS) technique. After direct evaluation of the chromatographic variables - co-solvent content, mobile phase flow rate, automated backpressure regulator pressure (ABPR), and column temperature - involved in the separation mechanism and assessment of the interactions among these variables, the optimal SFC-MS/MS working conditions were selected as a CO2/2% formic acid-methanol mobile phase, 1.

Changes of field incurred chlorpyrifos and its toxic metabolite residues in rice during food processing from-RAC-to-consumption.

The objectives of this study were to determine the effects of food processing on field incurred residues levels of chlorpyrifos and its metabolite 3,5,6-Trichloro-2-pyridinol (TCP) in rice. The chlorpyrifos and TCP were found to be 1.27 and 0.

Residues and dissipation kinetics of triazole fungicides difenoconazole and propiconazole in wheat and soil in Chinese fields.

An analytical method for simultaneously determining the residues of difenoconazole and propiconazole in wheat straw, wheat grain and soil was developed. Mean recoveries and relative standard deviations in all samples ranged 86.2-101.

Thiabendazole uptake in shimeji, king oyster, and oyster mushrooms and its persistence in sterile and nonsterile substrates.

Thiabendazole in the substrates incurred from spraying and premixing was translocated to the pileus, stipe, and volva of selected mushrooms. The spraying on the substrates resulted in higher residues of thiabendazole in all three mushrooms than the premixing treatment. For premixing, in the five substrates, half-lives of thiabendazole were found to be 13.

Simultaneous determination of seven neonicotinoid pesticide residues in food by ultraperformance liquid chromatography tandem mass spectrometry.

The present study developed an improved analytical method for simultaneous quantification of seven neonicotinoids in food by ultraperformance liquid chromatography combined with electrospray ionization triple quadrupole tandem mass spectrometry (UPLC-MS/MS) under the multiple reaction monitoring (MRM) mode. The optimization of extraction, cleanup, UPLC separation and MS/MS parameters of analytes were especially focused on. The low limits of quantification (LOQs) of neonicotinoids ranged from 0.