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Des Moines, IA, United States

China Green Agriculture, Inc. is based in Xi'an, China. It became the first Chinese company listed on the New York Stock Exchange market. It is also the first Chinese company to list on NYSE Euronext markets in 2009. It became a public company in 2008. China Green Agriculture produces and distributes humic acid based liquid compound fertilizer. Tao Li is the chief executive officer of China Green Agriculture. Wikipedia.


Liu X.,Institute of Plant Protection | Tian Y.,Institute of Plant Protection | Dong F.,Institute of Plant Protection | Xu J.,Institute of Plant Protection | And 4 more authors.
Journal of AOAC International | Year: 2014

An ultra-performance LC/tandem MS (UPLC/MS/MS) method for the simultaneous quantification and identification of matrine and berberine, alkaloids widely used in plant fungicides, has been developed and validated. Methanol or 1% ammonia-acetonitrile were selected as extraction solvents, and primary secondary amine sorbent was chosen for cleanup to achieve satisfactory recoveries in accordance with European Union guidelines. The chromatographic separation was carried out on a hydrophilic interaction LC column with a UPLC/MS/MS-based method to improve the retentions and shapes of the peaks. Method validation was performed for linearity, repeatability, interday precision, and sensitivity. Recoveries and RSDs were acceptable (73.1-109.3% recovery, RSD < 15.8%). The LODs varied from 0.34 to 1.07 μg/kg for matrine and 0.09 to 0.18 μg/kg for berberine, while the LOQs ranged from 1.12 to 3.58 μg/kg for matrine and 0.31 to 0.60 μg/kg for berberine. This method was successfully and efficiently applied for the analysis of matrine and berberine in real samples. Source


Li Y.,Chinese Academy of Agricultural Sciences | Dong F.,Chinese Academy of Agricultural Sciences | Liu X.,Chinese Academy of Agricultural Sciences | Xu J.,Chinese Academy of Agricultural Sciences | And 4 more authors.
Analytical and Bioanalytical Chemistry | Year: 2011

A rapid and simple miniaturized liquid-liquid extraction method has been developed for the determination of topramezone in soil, corn, wheat, and water samples using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-electrospray ionization (ESI)/MS/MS). The established method for the extraction and purification procedure was based on liquid-liquid partitioning into an aqueous solution at a low pH (pH ≈ 2.5), followed by back-partitioning into water at pH > 9. Two precursor, product ion transitions for topramezone were measured and evaluated to provide the maximum degree of confidence in the results. Under negative ESI conditions, quantitation was achieved by monitoring the fragment at m/z = 334 and the qualitative fragment at m/z = 318, whereas also collecting the corresponding parent ion at m/z = 362. Chromatographic separation was achieved using gradient elution with a mobile phase consisting of methanol and a 0.01% aqueous ammonium hydroxide solution. Recovery studies for soil, corn, wheat, and water were conducted at four different topramezone concentrations (5 or 10, 50, 100, and 1,000 μg kg-1); the overall average recoveries ranged from 79.9% to 98.4% with intra-day relative standard deviations (RSD) of 3.1~8.7% and inter-day RSD of 4.3~7.5%. Quantitative results were determined from calibration curves of topramezone standards containing 1-500 μg L-1 with an R2 ≥ 0.9994. Method sensitivities expressed as limits of quantitation were typically 6, 8, 9, and 1 μg kg-1 in soil, corn, wheat, and water, respectively. The results of the method validation confirmed that this proposed method was convenient and reliable for the determination of topramezone residues in soil, corn, wheat, and water. [Figure not available: see fulltext.] © 2011 Springer-Verlag. Source


Tian Y.,Chinese Academy of Agricultural Sciences | Liu X.,Chinese Academy of Agricultural Sciences | Dong F.,Chinese Academy of Agricultural Sciences | Xu J.,Chinese Academy of Agricultural Sciences | And 4 more authors.
Journal of AOAC International | Year: 2012

A sensitive and effective method for the simultaneous quantitative determination of aminopyralid, clopyralid, and picloram in vegetables (eggplant, cucumber, and tomato) and fruits (apple and grape) was developed and validated using ultra-performance LC coupled with MS/MS. The three herbicides were successfully separated and independently confirmed in a single run. Different extraction and cleanup methods were used to optimize the pretreatment processes of the residue analysis method. The final method is straightforward and involves extraction with 1% formic acid-acetonitrile, and no complicated cleanup process is needed. Determination of the compounds was achieved within 3.0 min. Respective average recoveries using this method at four concentration levels (0.05, 0.1, 0.5, and 1.0 mg/kg) ranged from 66.5 to 109.4%, with RSDs in the range of 1.1-19.7% (n = 5) for all analytes. The LODs were below 0.010 mg/kg, and the LOQs did not exceed 0.036 mg/kg, which were lower than the maximum residue limits (MRLs) of 0.5-5.0 mg/kg clopyralid in vegetables and fruits samples, as established by the European Union. This study provides a theoretical basis for China to develop MRLs and an analytical method for aminopyralid, clopyralid, and picloram in vegetables and fruits. © 2012 Publishing Technology. Source


Li Y.,Chinese Academy of Agricultural Sciences | Dong F.,Chinese Academy of Agricultural Sciences | Liu X.,Chinese Academy of Agricultural Sciences | Xu J.,Chinese Academy of Agricultural Sciences | And 6 more authors.
Journal of Chromatography A | Year: 2011

A novel and sensitive method was developed for the simultaneous determination of fenbuconazole and its main metabolites enantioselectively using chiral liquid chromatography coupled with tandem mass spectrometry. The separation and determination were performed using reversed-phase chromatography on a cellulose chiral stationary phase, a Chiralcel OD-RH (150mm×4.6mm) column, under isocratic conditions at 0.5mL/min flow rate. The effects of three cellulose-based columns and three amylose-based columns on the separation were also investigated. The elution orders of the eluting enantiomers were identified by an optical rotation detector. The QuEChERS (acronym for Quick, Easy, Cheap, Effective, Rugged and Safe) method and solid-phase extraction (SPE) were used for the extraction and clean-up of the soil and water samples, respectively. Parameters including the matrix effect, linearity, precision, accuracy and stability were evaluated. Under optimal conditions, the mean recoveries for all enantiomers from the soil samples were 82.5-104.1% with 2.7-9.5% intra-day relative standard deviations (RSD) and 5.7-11.2% inter-day RSD at 5, 25 and 50μg/kg levels; the mean enantiomer recoveries from the water samples were 81.8-104.6% with 2.6-11.4% intra-day RSD and 5.3-10.4% inter-day RSD at 0.25, 0.5 and 2.5μg/L levels. Coefficients of determination R2≥0.9991 were achieved for each enantiomer in the soil and water matrix calibration curves within the range of 1.0-125μg/L. The limits of detection (LOD) for all enantiomers in the soil and water were less than 0.8μg/kg, whereas the limit of quantification (LOQ) did not exceed 2.5μg/kg. The results of the method validation confirm that this proposed method is convenient and reliable for the enantioselective determination of the enantiomers of fenbuconazole and its main metabolites in soil and water. © 2011. Source


Chen X.,Chinese Academy of Agricultural Sciences | Dong F.,Chinese Academy of Agricultural Sciences | Liu X.,Chinese Academy of Agricultural Sciences | Xu J.,Chinese Academy of Agricultural Sciences | And 4 more authors.
Journal of Separation Science | Year: 2012

An effective chiral analytical method was developed for the resolution and determination of dinotefuran enantiomers in rice, tomato and apple samples. Dinotefuran enantiomers were baseline-separated and determined on a novel chiral column, ChromegaChiral CCA, with n-hexane-ethanol-methanol (85:5:10, v/v/v) as the mobile phase at a flow rate of 1.0mL/min with UV detection at 270nm. The resolution of dinotefuran enantiomers was about 1.8. The first eluted enantiomer was (+)-dinotefuran and the second eluted one was (-)-dinotefuran. The effects of mobile-phase composition and column temperature on the enantioseparation were evaluated. The method was validated for linearity, repeatability, accuracy, LOD and LOQ. LOD was 0.15g/kg in rice and tomato, 0.05g/kg in apple, with an LOQ of 0.5amg/kg in rice and tomato, 0.2mg/kg in apple. The average recoveries of the pesticide from all matrices ranged from 75.8 to 92.9% for all fortification levels The precision values associated with the analytical method, expressed as RSD values, were <16.5% for the pesticide in all matrices. The methodology was successfully applied for the enantioselective analysis of dinotefuran enantiomers in real samples, indicating its efficiency in investigating the environmental stereochemistry of dinotefuran in food matrix. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

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