Pengjie Luo,Xia Chen,Jing Xiao,Yunfeng Zhao,Zifei Wang
In recent years, fungicides have been frequently detected in soil, water, and air because of their extensive use, with detrimental effects on the environment. Therefore, the screening of foods for iprodione (IPRO) has become mandatory. A rapid, specific and sensitive method based on an immunochromatographic strip test has been developed for the determination of IPRO residues in cucumber and apple. The antigen IPRO-ovalbumin and a goat anti-mouse IgG antibody were drawn onto a nitrocellulose membrane as the test and control lines, respectively. Under optimal conditions, the cut-off limits of the semi-quantitative strip test for IPRO was as low as 10 ng/mL in 0.01 M PBS pH 7.4, 20 ng/mL in cucumber juice, and 25 ng/mL in apple juice and the results were obtained within 5 min. Our data suggests that this immunochromatographic assay can be used for the sensitive, rapid, and specific on-site screening of IPRO in cucumber and apple.
Yang Li,Xiaohuan Zang,Yahuan Li,Shuaihua Zhang,Chun Wang,Zhi Wang
A defective UiO-66 with rich defect sites was synthesized by a modulator-induced defect formation approach and used as the solid-phase microextraction (SPME) fiber coating material. The extraction experimental results showed that the defective UiO-66 coating can selectively extract the fungicides chlorothalonil, vinclozolin, dimethachlon, procymidone and iprodione with a high adsorption capability. The superior adsorption capability can be attributed to hydrophobic, Lewis acid-base and hydrogen bonding interactions. After optimization, a SPME with the defective UiO-66 as the fiber coating combined with GC–MS detection was established for the sensitive and selective determination of the five fungicides in fruit samples. Under the optimized experimental conditions, the quantitative linear response was in the range of 0.83–300 ng g −1 , with the coefficients of determination in the range from 0.9970 to 0.9986 and the limits of detection between 0.25 and 9.0 ng g −1 for the analytes. The method was successfully applied for the determination of the fungicides in different fruit samples. Satisfactory method recoveries (82.7%-117.7%) and good precisions with the relative standard deviations being from 3.2% to 12% were achieved.
The rubber tree ( Hevea brasiliensis ) is the only resource for commercial natural rubber production and thus has economic importance in Southeast Asia. A spot disease on the leaves of a rubber tree was first discovered in 2017 in Hainan, China. In this study, the fungal isolate MA1 from the infected tissues was determined to be a pathogen of the spot disease by satisfying Koch's postulates. The isolate MA1 was identified as Bipolaris bicolor based on the morphological characteristics and multigene phylogenetic analysis. Among fungicides, prochloraz, iprodione and pyraclostrobin significantly inhibited hyphal growth of B. bicolor under in vitro conditions. This study constitutes the first report on the association of B. bicolor with leaf spot disease of rubber trees worldwide.
危险品化学品经营许可证（带存储）