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RATIONALE Nitromezuril is a novel triazine compound possessing remarkable anticoccidial activity that could have possible future use in the prevention of coccidiosis; however, its metabolic characteristics have still not been revealed. METHODS In the present study, the in vitro metabolism of nitromezuril in HepG2 cells, rat S9 and primary hepatocytes was investigated using high-performance liquid chromatography with electrospray ionization tandem mass spectrometry. The structures of metabolites and their product ions were easily and reliably characterized based on the accurate MS2 spectra and known structure of nitromezuril. RESULTS As expected, three metabolites (M1–M3) were detected in a HepG2 cells system, one metabolite was respectively detected and identified as M1 in rat S9 and M2 in rat primary hepatocytes. M1 and M2 were confirmed respectively based on comparing their retention times, full scan, product ion scan with available authentic standards and M3 was tentatively identified as hydroxyl compound of M2. CONCLUSIONS Pathways of nitromezuril were reported for the first time and no obvious species difference was shown. The proposed metabolic pathways of nitromezuril can be expected to play a key role in pharmacodynamics and food safety evaluations. Copyright © 2014 John Wiley & Sons, Ltd.

Several Acalypha australis Linn. species are used in traditional medicine in Southeast Asia. In this work, the ultra-performance liquid chromatography/mass spectrometry fingerprints and the antibacterial activities of A. australis Linn. were investigated. An in-depth discussion on the reliability of identifying and obtaining potentially active compounds by spectrum-effect relationship and semi-preparative high performance liquid chromatography was conducted. The result shows that gallic acid and a compound with molecular weight of 634.1 in the fingerprints were the main antibacterial compounds. Compared to the crude extract of A. australis Linn., both compounds increase the antibacterial efficacy 10 to 20 times. Compounds with molecular weights of 154.0, 292.0, and 485.1 in the fingerprints were the auxiliary antibacterial compounds. Through the entire isolation procedure, we obtained these antibacterial compounds with purities of 92.53, 87.98, 90.73, 89.36, and 88.14%, respectively. This work provides a general model of the combination of ultra-performance liquid chromatography/mass spectrometry fingerprinting and antibacterial test to study the spectrum-effect relationships of A. australis Linn. This model can be used to discover further the active compounds of this herb.

Ce-doped silica films with various Ce concentrations were prepared via ion beam sputtering (IBS) and ion implantation. The samples containing 1.46 at.% Ce were annealed at various temperatures from 500 to 1100 °C in air ambient and a separate sample with the same Ce concentration was annealed at 1100 °C in nitrogen gas. The Ce-related photoluminescence (PL) was observed for the samples and found to be sensitive to the Ce concentrations, annealing conditions and fabricating processes. The PL intensity increases with increasing Ce concentrations from 0.09 to 0.58 at.%, and the concentration-induced quenching effect occurred as the Ce concentrations reached 1.46 at.%. Also, the PL intensity is enhanced as the samples were annealed at various temperatures from 500 to 900 °C in air ambient, then decreases remarkably as the annealing temperature reached 1100 °C. In addition, compared with the sample annealed in air, the PL intensity can be enhanced for the sample annealed in nitrogen gas. Distinctive PL spectra were found for the samples prepared via different processes.