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Fluazifop‐p‐butyl (FPB) is used to control the gramineous weeds in Panax ginseng field, which has the risk of exceeding the maximum residue limit of FPB in Panax ginseng. A modified QuEChERS sample preparation method was developed for the simultaneous determination of FPB and its two major relevant metabolites, fluazifop‐p‐acid (FP) and 2‐hydroxy‐5‐ trifluoromethylpyridin (TFMP) in Panax ginseng by using Carboxylated multi‐walled carbon nanotubes (MWCNTs‐COOH) mixed with ostade‐cylsilane (C18), primary secondary amine (PSA), and graphitized carbon black (GCB) as purification materials. Furthermore, the HPLC‐MS/MS parameters were optimized. The method was further validated by determining the linearity (R2>0.999), fortified recovery (77.6‐97.8%), relative standard deviation (<13.6%) and sensitivity (LOQ, 2.0‐ 8.6 μg kg‐1 for FPB, 3.9‐5.8 μg kg−1 for FP and 3.5‐9.0 μg kg−1 for TFMP in Panax ginseng root, leaf, and seed samples, respectively). The main advantages of the method are high recovery, high sample throughput, facile sample preparation, a smaller volume of organic solvents and low cost per sample. The entire method can withstand practice testing expected to be used for the screening of FPB residue in Panax ginseng samples. [ABSTRACT FROM AUTHOR]

By enrichment culturing of soil contaminated with metribuzin, a highly efficient metribuzin degrading bacterium,Bacillussp. N1, was isolated. This strain grows using metribuzin at 5.0% (v/v) as the sole nitrogen source in a liquid medium. Optimal metribuzin degradation occurred at a temperature of 30ºC and at pH 7.0. With an initial concentration of 20 mg L−1, the degradation rate was 73.5% in 120 h. If the initial concentrations were higher than 50 mg L−1, the biodegradation rates decreased as the metribuzin concentrations increased. When the concentration was 100 mg L−1, the degradation rate was only 45%. Degradation followed the pesticide degradation kinetic equation at initial concentrations between 5 mg L−1and 50 mg L−1. When the metribuzin contaminated soil was mixed with strain N1 (with the concentration of metribuzin being 20 mg L−1and the inoculation rate of 1011g−1dry soil), the degradation rate of the metribuzin was 66.4% in 30 days, while the degradation rate of metribuzin was only 19.4% in the control soil without the strain N1. These results indicate that the strain N1 can significantly increase the degradation rate of metribuzin in contaminated soil. [ABSTRACT FROM PUBLISHER]

By enrichment culturing of the sludge collected from the industrial wastewater treatment pond, we isolated a highly efficient nicosulfuron degrading bacterium Serratia marcescens N80. In liquid medium, Serratia marcescens N80 grows using nicosulfuron as the sole nitrogen source, and the optimal temperature, pH values, and inoculation for degradation are 30–35°C, 6.0–7.0, and 3.0% (v/v), respectively. With the initial concentration of 10 mg L−1, the degradation rate is 93.6% in 96 hours; as the initial concentrations are higher than 10 mg L−1, the biodegradation rates decrease as the nicosulfuron concentrations increase; when the concentration is 400 mg L−1, the degradation rate is only 53.1%. Degradation follows the pesticide degradation kinetic equation at concentrations between 5 mg L−1 and 50 mg L−1. Identification of the metabolites by the liquid chromatography/mass spectrometry (LC/MS) indicates that the degradation of nicosulfuron is achieved by breaking the sulfonylurea bridge. The strain N80 also degraded some other sulfonylurea herbicides, including ethametsulfuron, tribenuron-methyl, metsulfuron-methyl, chlorimuron-ethyl,and rimsulfuron. [ABSTRACT FROM AUTHOR]

An ionic liquid-based ultrasonic-assisted extraction (ILUAE) method was developed for the extraction of the two forsythosides, namely forsythosides I and A from the leaf of Forsythia suspensa (Thunb.) Vahl. Three kinds of l-alkyl-3-methylimidazolium ionic liquids with different alkyl chain and anion were investigated. The results indicated that ionic liquids showed remarkable effects on the extraction yields of forsythosides. In addition, several ILUAE ultrasonic parameters, such as the solvent concentration, solvent to solid ratio and extraction time have been optimized. Under these optimal conditions (e.g., with 0.6 M [C6MIM]Br, solvent to solid ratio of 15 mL/g and extraction time of 10 min), this approach gained the highest extraction yields of forsythoside I (0.89%) and forsythoside A (10.74%). Meanwhile, forsythosides in the ILUAE extract were separated and purified successfully through the high-speed counter-current chromatography with a two-phase solvent system consisting of ethyl acetate-ethanol-acetic acid-water (4 : 1 : 0.25 : 6, v/v). 5.4 mg of forsythoside I and 59.7 mg of forsythoside A were obtained from 120 mg of the prepurified sample in one-step separation, with the purity of 96.1 and 97.9%, respectively, as determined by high-performance liquid chromatography. Their structures were identified by (1)H nuclear magnetic resonance (NMR) and (13)C NMR., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)