Deng Pengyu, Mou Lianhong, Ou Guipeng, Luo Xin, Hu Deyu, Zhang Yuping
National Key Laboratory of Green Pesticide, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for R&D of Fine Chemicals, Guizhou University, Guiyang 550025, China.
Foods. 2023 May 30;12(11):2200. doi: 10.3390/foods12112200.
Herein, an accurate and sensitive method was developed for detecting four stereoisomers of propiconazole in "Fengtang" plum by LC-MS/MS. The mean recovery of four propiconazole stereoisomers ranged from 79.42 to 104.10% at three adding levels with reasonable RSD of 1.54-11.68%, and the LOD and LOQ of the four stereoisomers was 0.0005 mg/kg and 0.004 mg/kg, respectively. In addition, the residue and selective degradation of propiconazole stereoisomers in plums were investigated by storage at 20 °C and 4 °C. The half-lives of propiconazole stereoisomeric during storage were 9.49-15.40 d at 20 °C, and 21.00-28.88 d at 4 °C. The degradation of (2R,4R)-propiconazole and (2R,4S)-propiconazole in stored plums was slightly slower than that of the corresponding enantiomers (2S,4S)-propiconazole and (2S,4R)-propiconazole. The total residues of propiconazole were 0.026-0.487 mg/kg in the plum storage period, and the water washing could remove 49.35% to 54.65% of the propiconazole residue in plum. The hardness of plums treated with propiconazole was generally higher than that of control in the middle and late stages of storage. The effects of propiconazole on the total soluble solid content of plums were different at 20 °C and 4 °C. This study provides a scientific reference for the food safety evaluation of the "Fengtang" plum after the application of propiconazole during the storage period.
本文建立了一种准确、灵敏的液相色谱-串联质谱法（LC-MS/MS），用于检测“凤塘”李中丙环唑的四种立体异构体。丙环唑四种立体异构体在三个添加水平下的平均回收率为79.42%至104.10%，相对标准偏差（RSD）合理，为1.54%至11.68%，四种立体异构体的检测限（LOD）和定量限（LOQ）分别为0.0005 mg/kg和0.004 mg/kg。此外，通过在20℃和4℃下储存，研究了丙环唑立体异构体在李子中的残留和选择性降解情况。丙环唑立体异构体在储存期间的半衰期在20℃下为9.49至15.40天，在4℃下为21.00至28.88天。储存李子中（2R,4R）-丙环唑和（2R,4S）-丙环唑的降解略慢于相应对映体（2S,4S）-丙环唑和（2S,4R）-丙环唑。李子储存期间丙环唑的总残留量为0.026至0.487 mg/kg，水洗可去除李子中49.35%至54.65%的丙环唑残留。在储存中期和后期，用丙环唑处理的李子硬度普遍高于对照。丙环唑对李子总可溶性固形物含量的影响在20℃和4℃下有所不同。本研究为“凤塘”李在储存期施用丙环唑后的食品安全评价提供了科学参考。
