食用菌甲醛含量测定的柱前衍生条件优化及其应用

Determination of formaldehyde in edible fungi by optimizing the pre-column derivatization and its application

中文关键词:  食用菌  甲醛  衍生条件  优化

英文关键词:edible fungi  formaldehyde  derivatization condition  optimization

中文摘要:

      目的 对食用菌甲醛含量测定中的衍生条件进行优化, 并检测6种常见食用菌的甲醛含量。方法 样品匀浆后, 4 °C超声30 min, 滤液加一定量的缓冲液及2,4-二硝基苯肼, 一定温度下衍生一定时间, 冷却后用二氯甲烷萃取3次, 氮吹至干, 乙腈定容, 然后采用液相色谱法检测, 外标法定量。结果 甲醛与2,4-二硝基苯肼在pH为5.0时反应趋向稳定, 温度在80 °C、时间为100 min时衍生效果最好。该方法回收率在90.59%~97.80%之间, 相对标准偏差1.95%~4.61%, 稳定性和重现性的相对标准偏差分别为0.90%、2.72%。进一步将该方法应用于海鲜菇、金针菇、茶树菇、黑木耳、毛木耳、杏鲍菇等食用菌的甲醛含量测定, 结果显示, 以上食用菌的甲醛含量在0.52~0.81 μg/g, 均未超标; 加标回收率均在85%以上。结论 该方法稳定, 准确度和精密度好, 适用于食用菌甲醛的检测。

英文摘要:

      Objective To optimize the derivatization condition for the determination of formaldehyde content in edible fungi, and determine the formaldehyde content of 6 kinds of common edible fungi. Methods The samples were treated with ultrasonic for 30 min at 4 °C after homogenizing. A certain amount of buffer solution and 2, 4-dinitrophenylhydrazine were added to the filtrate, which were derived for a certain time at a certain temperature. After cooling, the sample was extracted with dichloromethane for 3 times, blew dry with nitrogen and diluted with acetonitrile, then it was determined by liquid chromatography, and quantified by external standard method. Results The reaction of formaldehyde and 2,4-dinitrophenylhydrazine was stable at pH 5.0, the derivative effect was best at 80 °C for 100 min. The average recoveries were 90.59%–97.80%, and the relative standard deviations were 1.95%–4.61%. The relative standard deviation of stability and reproducibility were 0.90% and 2.72%, respectively. The method was further applied to the determination of formaldehyde content in Hypsizygus marmoreus, Flammulina velutipes, Agrocybe aegerita, Auricularia auricular, Auricularia polytricha, Pleurotus eryngii and other edible fungi. The results showed that the formaldehyde content in the above edible fungi was within 0.52–0.81 μg/g, which did not exceed the standard. The recovery rates were above 85%. Conclusion This method is stable, accurate, precise and suitable for detecting formaldehyde in edible fungus.