Degradation And Metabolism Of Dinotefuran In Brassica Oleracea

Dinotefuran is the third generation of super nicotine insecticide developed by Mitsui Corporation of Japan.The drug was approved for registration in China in 2013,but there are few studies on the use and remnant dynamics of dinotefuran in China.At present,we have reported the simultaneous detection of dinotefuran and its metabolites DN and UF residues in the analysis method,this paper established a simultaneous detection of dinotefuran and its metabolites DN,UF in the cabbage residue on the residual analysis method.Then,the residual dynamics of dinotefuran and its metabolites DN and UF in cabbage were studied by field experiment.The degradation of dinotefuran,DN and UF in cabbage was studied.Diclofenac can be used safely and safely,to evaluate its digestive dynamics on the cabbage,the residual situation and the destruction of the ecological environment and to ensure the quality and safety of agricultural products to provide a scientific basis.The main findings are as follows:1.A method for the simultaneous analysis and detection of dinotefuran and its major metabolites DN and UF from the cabbage substrate was established.The extraction method of dinotefuran and its main metabolites DN and UF in cabbage samples was extracted by 1% acetic acid in acetonitrile solution,and detected by liquid phase and tandem mass spectrometry(UPLC-MS / MS)method.The average recoveries of DN10 were 81.2% ~ 113.7% and the relative standard deviations(RSD)were 2.88% ~ 11.74%.The average recoveries of metabolite DN were 80.0% ~ 110.1%,RSD was 1.98% ~ 9.96% The average recoveries of UF were 91.0% ~ 108.1% and the RSD was 2.70% ~ 11.21%.The minimum detection concentration of dinotefuran and its main metabolites DN and UF in cabbage were 0.04 mg / kg.2.The field experiments of Hefei,Wuhan and Zhanjiang showed that the digestion half-life of dwarfenema in cabbage was 1.5 days.The digestion half-life of metabolite DN in cabbage was 4.5 d ~ 4.9 d.The half-life of diclofenac in soil was 2.3 d ~ 3.9 d.Dipyrazine is more susceptible to degradation in cabbage,while metabolite DN is slower relative to degradation.The degradation rate of dinotefuran is much faster than that of metabolite DN,while the other metabolite UF is not detectable.3.Spray 25% diclofenac dispersible oil suspension on the field cabbage to understand the infiltration and degradation of dinotefins and metabolites in different positions of cabbage over time.The results showed that the degradation rate of dinotefuran on the leaves of the first layer was faster than that of the other layers,and the residual amount of dinotefuran could be detected in the third layer of the cabbage crop.While the residual amount of its metabolite DN reached its peak on day 5 and could be detected in the fifth layer of leaves,while the remaining amount of the other major metabolite UF was at a low level only in the first layer of leaves Can be detected and reached peak on day 5.4.Under the same conditions,three different manufacturers of dinotefuran preparations were tested to study the osmotic effects of the formulations produced by different manufacturers in cabbage leaves.The results showed that 20% diclofenac suspension and wettable powder had a better infiltration effect than 25% diclofenac dispersible oil suspending agent.