Kong Y.,Chinese Academy of Agricultural Sciences |
Zhang Q.,Chinese Academy of Agricultural Sciences |
Zhang Q.,Quality Inspection and Test Center for Oilseeds and Products |
Zhang W.,Chinese Academy of Agricultural Sciences |
And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010
With a screening hemisolid stem-cell culture, four positive hybridomas 2B12, 2C1, 2F1, and 3D4 were screened and used to prepare four correspondent monoclonal antibodies (McAbs) against the pyrethroid insecticide deltamethrin. These McAbs showed I 50 values in a range of 17-94 ng mL-1, from among which the antibody 2B12 with the lowest I50 value was selected to develop an optimized enzyme-linked immunosorbent assay (ELISA). In the developed ELISA, the I50 of deltamethrin was 17.0 ± 3.3 ng mL-1 and the limit of detection (LOD) was 1.2 ± 1.3 ng mL -1. There seemed to be little or no cross-reactivity with other tested pyrethroids and their metabolites. For validation of the assay method, environmental water samples fortified with deltamethrin were analyzed with the ELISA and gas chromatography (GC) methods. The recoveries of the developed ELISA ranged from 82 to 117%, which were close to those of the GC method (94-103%). These results suggested that the developed ELISA based on the McAb 2B 12 could be used for the rapid and sensitive determination of deltamethrin in environmental water. © 2010 American Chemical Society.
Zhang D.,Chinese Academy of Agricultural Sciences |
Zhang D.,Key Laboratory of Oil Crop Biology |
Zhang D.,Quality Inspection and Test Center for Oilseeds Products |
Li P.,Chinese Academy of Agricultural Sciences |
And 11 more authors.
Talanta | Year: 2011
To solve the problem of low selectivity of current immunochromatographic assay (ICA) for aflatoxin B1 (AFB1) alone detection, a novel selective ICA was developed here. With very high selectivity, a new AFB1 monoclonal antibody (MAb) 3G1 was preparaed by immunizing Balb/c mice with aflatoxin B2a-BSA (AFB2a-BSA) rather than AFB1-BSA used in other reports and 3G1 possessed the highest selectivity than those used in published ICAs. The ICA with visual detection limit (VDL) of 1 ng mL-1 showed no cross-reactivity with other aflatoxins. Comparing with previous reports, the ICA here provided the most powerful guarantee for avoiding false positive results leaded by coexistence of other aflatoxins in samples. For validation, naturally contaminated samples including peanut, puer-tea, vegetable oil and feedstuff were respectively assayed by ICA and a standard high performance liquid chromatography (HPLC), and good agreement of results was obtained between two methods. Therefore, the developed ICA could well meet the selective detection of AFB1 in agro-products. © 2011 Elsevier B.V. All rights reserved.
Chen R.,Chinese Academy of Sciences |
Chen R.,Key Laboratory of Oil Crop Biology |
Chen R.,Laboratory of Risk Assessment for Oilseeds Products |
Ma F.,Chinese Academy of Sciences |
And 25 more authors.
Food Chemistry | Year: 2014
Aflatoxins are a group of secondary metabolites produced by Aspergillus flavus and Aspergillus parasiticus with carcinogenicity, teratogenicity, and mutagenicity. Aflatoxins may be found in a wide range of agri-products, especially in grains, oilseeds, corns, and peanuts. In this study, the conditions for detoxifying peanuts by ozonation were optimised. Aflatoxins in peanuts at moisture content of 5% (w/w) were sensitive to ozone and easily degraded when reacted with 6.0 mg/l of ozone for 30 min at room temperature. The detoxification rates of the total aflatoxins and aflatoxin B1 (AFB1) were 65.8% and 65.9%, respectively. The quality of peanut samples was also evaluated in this research. No significant differences (P > 0.05) were found in the polyphenols, resveratrol, acid value (AV), and peroxide value (PV) between treated and untreated samples. The results suggested that ozonation was a promising method for aflatoxin detoxification in peanuts. © 2013 Published by Elsevier Ltd.
Fan S.,Chinese Academy of Agricultural Sciences |
Fan S.,Key Laboratory of Oil Crop Biology |
Wang X.,Chinese Academy of Agricultural Sciences |
Wang X.,Key Laboratory of Oil Crop Biology |
And 8 more authors.
Journal of Separation Science | Year: 2011
In the experiment, a high-performance liquid chromatography and electrospray ionization-tandem mass spectrometry with selected reaction monitoring was used to simultaneously determine various classes of phytohormones, including indole-3-acetic acid, α-naphthaleneacetic acid, 2-chlorobenzoic acid, 4-chlorobenzoic acid, indole-3-butyric acid, gibberellic acid, 2,4-dichlorophenoxyacetic acid, 2-naphthoxyacetic acid, abscisic acid, 2,3,5-triiodobenzoic acid, uniconazole, paclobutrazol and 2,4-epibassinolide in rape tissues. The analyses were separated by an HPLC equipped with a reversed-phase column using a binary solvent system composed of methanol and water, both containing 0.1% of formic acid. The matrix effect was also considered and determined. The technology was applied to analyze rape tissues, including roots, stems, leaves, flowers, immature pods and rape seeds. The rape tissues were subjected to ultrasound-assisted extraction and purified by dispersive solid-phase extraction, and then transferred into the liquid chromatography system. The detection limit for each plant hormone was defined by the ratio of signal/background noise (S/N) of 3. The results showed perfect linearity (R2 values of 0.9987-1.0000) and reproducibility of elution times (relative standard deviations, RSDs,<1%) and peak areas (RSDs,<7%) for all target compounds. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Hou L.,CAS Nanjing Institute of Soil Science |
Hou L.,South China Agricultural University |
Shi W.,CAS Nanjing Institute of Soil Science |
Wei W.,Key Laboratory of Oil Crop Biology |
Shen H.,South China Agricultural University
Biological Trace Element Research | Year: 2011
Information on cadmium (Cd) uptake and transport is essential to understand better the physiology of Cd tolerance in plants. In this study, Cd uptake, translocation, and tolerance were investigated in AHA1 (Arabidopsis plasma membrane H+-ATPase gene) overexpressed plants. Exposed to 10 μM CdCl2, AHA1OX showed a higher root elongation, accumulated more Cd, and maintained better integrity of nucleus membrane of root tips in comparison to the control plant (WT), suggesting that AHA1OX was more Cd tolerant than WT. To investigate Cd tolerance mechanism of AHA1OX plants, we measured the activity of plasma membrane H+-ATPase and the secretion of citrate. Results indicated that treatment with 10 μM of Cd stimulated the activity of plasma membrane H+-ATPase and the secretion of citrate, while 30 μM of Cd inhibited them. AHA1OX had higher activity of H+-ATPase and secretion of citrate than WT. Addition of citrate enhanced root-to-shoot translocation of Cd significantly. A higher root-to-shoot Cd translocation was observed in AHA1OX than in WT plants. Treatment with low temperature or metabolic inhibitor (carbonyl cyanide m-chlorophenylhydrazone) inhibited Cd uptake and translocation. The study of Cd forms using sequential extraction indicated that Cd was mainly present as a protein-bound form, and AHA1OX had more water-soluble Cd than WT. Taken together, our results suggested that the Cd tolerance of AHA1OX was associated with its root-to-shoot Cd translocation and secretion of citrate, which converts Cd2+ into less toxic and more easily transportable forms in plant cells. © 2010 Springer Science+Business Media, LLC.