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Wang C.-S.,National Chung Hsing University | Lin W.-T.,National Chung Hsing University | Chiang Y.-J.,Agricultural Chemicals and Toxic Substances Research Institute | Wang C.-Y.,National Chung Hsing University
Weed Science | Year: 2017

Fluazifop-P-butyl, a selective graminicide, has been widely used to control annual grass weeds for more than three decades in Taiwan, and a resistant (R) biotype of goosegrass has consequently appeared. In this study, liquid chromatography/tandem mass spectrometry (LC/MS/MS) was applied to analyze metabolites of fluazifop-P-butyl in a R biotype of goosegrass. Six signals, including mass-to-charge ratios (m/z) 512, 432, 423, 415, 314, and 160, in positive scanning mode, and four signals, including m/z 788, 623, 593, and 162, in negative scanning mode, were found in the metabolites of the R and S biotypes, respectively. All of the signals of these metabolites in the R biotype showed higher intensity than those of the S biotype, except for m/z 162. Based on the molecular weights of the fragments (MS2 signal) from the molecules (MS1 signal) and comparison with the Metabolite Link Metabolomics database, MassBank database, and related references, one reduced form of fluazifop acid, i.e., 2-[4-(5-trifluoromethyl-2-pyridyloxy) phenoxy] propanol (MW 313); two types of intermediates of MW 163, i.e., 5-trifluoromethyl-2-pyridone and 5-trifluoromethyl-2-hydroxypyridine (or 2-hydroxy-5-trifluoromethyl pyridine); and five possible conjugated compounds containing a common core fragment (MW 255) from fluazifop acid were identified. In addition, another compound, likely degraded from one of the five conjugated compounds, was also detected. Accordingly, the metabolic pathway of fluazifop-P-butyl in goosegrass is described in this study. An enzyme kinetic study on glutathione S-transferase showed that the R biotype has higher affinities to the substrates reduced glutathione (GSH) and 1-chloro-2, 4-dinitrobenzene, with S/R Km ratios of 3.0 and 2.4, respectively. No difference in Vmax was found, revealing that the S biotype has a strong ability to bind GSH and herbicide or target molecules and showed susceptibility to fluazifop. © Weed Science Society of America, 2017.


Wang T.-C.,National Taiwan University | Wang T.-C.,Agricultural Chemicals and Toxic Substances Research Institute | Nai Y.-S.,National Taiwan University | Wang C.-Y.,National Taiwan University | And 5 more authors.
Journal of Invertebrate Pathology | Year: 2013

A new microsporidium was isolated from the endemic, Taiwanese shrimp, Caridina formosae (Decapoda, Atyidae) from northern Taiwan. A conspicuous symptom of infection was presence of opaque white xenomas located in the proximity of the alimentary tract, the surface of the hepatopancreas, and the gills. A fully developed xenoma consisted of a hard, thick capsule filled with sporophorous vesicles containing multiple spores. Microsporidia developed synchronously within the same sporophorous vesicle, although the stage of parasite development differed among the vesicles. Fresh spores were pyriform, mononucleated and measured 6.53. ×. 4.38. μm. The polar filament was anisofilar with 9-11 coils. Phylogenetic analysis based on the small subunit ribosomal DNA sequence showed that the isolate is most similar to the fish microsporidian clade containing the genera Kabatana, Microgemma, Potaspora, Spraguea, and Teramicra. The highest sequence identity, 80%, was with Spraguea spp. Based on pathogenesis, life cycle and phylogenetic analysis, we erect a new genus and species, Triwangia caridinae for the novel microsporidium. © 2013 Elsevier Inc.


Fang C.-C.,National Taiwan University | Okuyama T.,National Taiwan University | Wu W.-J.,National Taiwan University | Feng H.-T.,Agricultural Chemicals and Toxic Substances Research Institute | Hsu J.-C.,National Taiwan University
Journal of Economic Entomology | Year: 2011

Naled is a commonly used insecticide for controlling populations of the oriental fruit fly, Bactrocera dorsalis (Hendel), in Taiwan and other countries. B. dorsalis has developed resistance to the insecticide, and the resistance management is an important issue. Ecological effects (e.g., fitness costs) of the resistance, when fully understood, can be used for the resistance management. This study examined the effects of the insecticide resistance on important life history traits (i.e., survival rates, stage durations, and fecundity) of the oriental fruit fly by comparing the traits of insecticide resistant individuals and susceptible individuals. Population dynamical properties were also examined using a stage-structured matrix model that was parameterized with the empirical data. The results revealed that susceptible individuals had shorter stage durations (e.g., grew faster) and reproduced more than resistant individuals. The average longevity of sexually mature susceptible adults was longer than that of sexually mature resistant adults. The matrix population model predicted that a population of the susceptible individuals would grow faster than a population of the resistant individuals in the absence of the insecticide. The sensitivity analysis of the model suggests that the sexually immature adult stage is a good candidate for controlling B. dorsalis populations. © 2011 Entomological Society of America.


PubMed | National Taiwan Ocean University, Agricultural Chemicals And Toxic Substances Research Institute, National Taiwan University, Academia Sinica, Taiwan and National Yang Ming University
Type: | Journal: Biosensors & bioelectronics | Year: 2015

The widespread and intensive use of neonicotinoid insecticides induces negative cascading effects on ecosystems. It is desirable to develop a portable sensitive sensing platform for on-site screening of high-risk pesticides. We combined an indirect competitive immunoassay, highly sensitive surface plasmon resonance (SPR) biochip and a simple portable imaging setup for label-free detection of imidacloprid pesticides. The SPR biochip consists of several capped nanoslit arrays with different periods which form a spectral image on the chip. The qualitative and semiquantitative analyses of pesticides can be directly observed from the spot shift on the chip. The precise semiquantitative analyses can be further completed by using image processing in a smartphone. We demonstrate simultaneous detection of four different concentrations of imidacloprid pesticides. The visual detection limit is about 1ppb, which is well below the maximum residue concentration permitted by law (20ppb). Compared to the one-step strip assay, the proposed chip is capable of performing semiquantitative analyses and multiple detection. Compared to the enzyme-linked immunosorbent assay, our method is label-free and requires simple washing steps and short reaction time. In addition, the label-free chip has a comparable sensitivity but wider working range than those labeling techniques.


Chung Y.-C.,China Medical University at Taichung | Hsieh F.-C.,Agricultural Chemicals and Toxic Substances Research Institute | Lin Y.-J.,China Medical University at Taichung | Wu T.-Y.,Chung Yuan Christian University | And 4 more authors.
European Journal of Pharmacology | Year: 2015

The aim of this study was to identify the active ingredients responsible for the anti-EV71 activity produced by Salvia miltiorrhiza extracts. A pGS-EV71 IRES-based bicistronic reporter assay platform was used for rapid analysis of compounds that could specifically inhibit EV71 viral IRES-mediated translation. The analysis identified 2 caffeic acid derivatives, magnesium lithospermate B (MLB) and rosmarinic acid (RA), which suppressed EV71 IRES-mediated translation at concentrations of 30 μg/ml. We also found that MLB and RA inhibited EV71 infection when they were added to RD cells during the viral absorption stage. MLB had a low IC50 value of 0.09 mM and a high TI value of 10.52. In contrast, RA had an IC50 value of 0.50 mM with a TI value of 2.97. MLB and RA (100 μg/ml) also reduced EV71 viral particle production and significantly decreased VP1 protein production. We propose that these two derivatives inhibit EV71 viral entry into cells and viral IRES activity, thereby reducing viral particle production and viral RNA expression and blocking viral VP1 protein translation. This study provides useful information for the development of anti-EV71 assays and reagents by demonstrating a convenient EV71 IRES-based bicistronic assay platform to screen for anti-EV71 IRES activity, and also reports 2 compounds, MLB and RA, which are responsible for the anti-EV71 activity of S. miltiorrhiza. © 2015 Elsevier B.V. All rights reserved.


PubMed | China Medical University at Taichung, Chung Yuan Christian University and Agricultural Chemicals and Toxic Substances Research Institute
Type: | Journal: European journal of pharmacology | Year: 2015

The aim of this study was to identify the active ingredients responsible for the anti-EV71 activity produced by Salvia miltiorrhiza extracts. A pGS-EV71 IRES-based bicistronic reporter assay platform was used for rapid analysis of compounds that could specifically inhibit EV71 viral IRES-mediated translation. The analysis identified 2 caffeic acid derivatives, magnesium lithospermate B (MLB) and rosmarinic acid (RA), which suppressed EV71 IRES-mediated translation at concentrations of 30g/ml. We also found that MLB and RA inhibited EV71 infection when they were added to RD cells during the viral absorption stage. MLB had a low IC50 value of 0.09mM and a high TI value of 10.52. In contrast, RA had an IC50 value of 0.50mM with a TI value of 2.97. MLB and RA (100g/ml) also reduced EV71 viral particle production and significantly decreased VP1 protein production. We propose that these two derivatives inhibit EV71 viral entry into cells and viral IRES activity, thereby reducing viral particle production and viral RNA expression and blocking viral VP1 protein translation. This study provides useful information for the development of anti-EV71 assays and reagents by demonstrating a convenient EV71 IRES-based bicistronic assay platform to screen for anti-EV71 IRES activity, and also reports 2 compounds, MLB and RA, which are responsible for the anti-EV71 activity of S. miltiorrhiza.


Wang R.-J.,Miaoli District Agricultural Research and Extension Station | Wang R.-J.,National Chung Hsing University | Yang C.-H.,Agricultural Chemicals and Toxic Substances Research Institute | Hu M.-L.,National Chung Hsing University
Journal of Agricultural and Food Chemistry | Year: 2010

1-Deoxynojirimycin (1-DNJ), an iminosugar rich in mulberry, has been shown to possess antimetastatic potential. The antimetastatic mechanisms of 1-DNJ in melanoma B16F10 cells were studied, as were the antimetastatic activity (cell adhesion, migration, and invasion) of 1-DNJ, matrix metalloproteinases (MMP-2 and MMP-9), tissue inhibitors of metalloproteinase (TIMP-1 and TIMP-2) mRNA, and flow cytometric analysis of cell surface in melanoma B16F10 cells. 1-DJ significantly inhibited invasion, migration, and cell-matrix adhesion and markedly decreased MMP-2 and MMP-9 activity and mRNA expression. In contrast, 1-DNJ effectively enhanced the expression of TIMP-2 mRNA. In addition, 1-DNJ significantly decreased abnormal glycosylation and/or sialylation on B16F10 melanoma cell surface but increased the levels of R-mannose. Thus, the antimetastatic effects of 1-DNJ against B16F10 melanoma cells are likely associated with its attenuated activities and expression of MMP-2/9, enhancement of the TIMP-2 mRNA expression, and alterations of the cell surface-binding motif. These results suggest that 1-DNJ may be useful as an adjuvant of antimetastatic agents such as cisplatin. © 2010 American Chemical Society.


Ko Y.-C.,National Chung Hsing University | Ko Y.-C.,Agricultural Chemicals and Toxic Substances Research Institute | Lee R.-J.,National Chung Hsing University | Feng H.-T.,Agricultural Chemicals and Toxic Substances Research Institute | Lee M.-R.,National Chung Hsing University
Journal of the Chinese Chemical Society | Year: 2013

A rapid, selective and sensitive method for analysis of trace flavonoids and its glycoside derivatives in ginkgo has proposed. Ultrasonic-assisted extraction of sample preparation was adopted to extract trace flavonoids in ginkgo leaf and its processed product. The compounds were identified using liquid chromatography negative electrospray ionization triple quadrupole tandem mass spectrometry (MS/MS). The neutral loss scan mode of MS/MS was used to screen flavonoid compounds and those compounds with acid group, or having rhamnosyl, glucosyl, or coumaroyl moiety in the samples. The successive data-dependent product ion scan mode of MS/MS was used to identify the structure of the components. The analytical results represented three aglycone flavonoids and seven flavonoid glycosides in ginkgo. The method detection limits were evaluated for the analytes analyzed in the range of 0.88 to 2.67 μg/mL. © 2013 The Chemical Society Located in Taipei &Wiley-VCH Verlag GmbH & Co. KGaA,Weinheim.


Ko Y.-C.,National Chung Hsing University | Ko Y.-C.,Agricultural Chemicals and Toxic Substances Research Institute | Feng H.-T.,Agricultural Chemicals and Toxic Substances Research Institute | Lee R.-J.,National Chung Hsing University | Lee M.-R.,National Chung Hsing University
Rapid Communications in Mass Spectrometry | Year: 2013

RATIONALE: Flavonoids in the medicinal plant Wikstroemia indica C. A. Mey. are present in trace amounts and found in complex matrices. An efficient and sensitive method is necessary for the rapid identification of such biomolecules. METHODS: Flavonoids were extracted with methanol via ultrasonicassisted extraction and analyzed by liquid chromatography with photodiode array detection and tandem mass spectrometry. The extract was analyzed and compounds were identified using negative electrospray ionization datadependent tandem mass spectrometry. RESULTS: The results confirmed the presence of three flavonoid compounds, seven biflavonoid compounds, and one coumarinlike compound, daphnoretin, in the extracts of different plant parts of W. indica. The method detection limit was evaluated down to 5 μg/g using kaempfol as a reference standard. CONCLUSIONS: The proposed method offers a rapid and reliable analysis for the determination of flavonoids in medicinal plants. Copyright © 2012 John Wiley & Sons, Ltd.


The present invention provides a quick extraction kit adapted to a procedure of detecting pesticide residues in agricultural products and a method of obtaining a primary test liquid from an agricultural sample by the quick extraction kit. The quick extraction kit comprises a pipe, a first powder mixture layer and a second powder mixture layer. The method of taking primary test liquid is performed as follows. First, obtaining fragments of the agricultural sample. Second, adding an extraction solvent into the fragments of the agricultural sample to obtain a sample solution. Third, adding the sample solution into the pipe. Finally, driving the sample solution to export from the pipe to become the primary test liquid. The quick extraction kit and the method solve the problem of being unable to quickly obtain the result of detecting pesticide residues.

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