基质辅助激光解析电离-飞行时间质谱法快速鉴定餐饮食品中的空肠弯曲菌

Rapid detection and identification of Campylobacter jejuni in food and beverage by matrix-assisted laser analytical ionization-time of flight mass spectrometry

中文关键词:  餐饮食品  空肠弯曲菌  基质辅助飞行时间质谱  鉴定

英文关键词:food and beverage  Campylobacter jejuni  matrix-assisted laser desorption ionization time of flight mass spectrometry  identification

中文摘要:

      目的 建立基质辅助激光解析电离-飞行质谱法(matrix assisted laser desorption ionization- time of flight mass spectrometry, MALDI-TOF-MS)快速鉴定餐饮食品中空肠弯曲菌的方法。方法 从餐饮样品中分离的疑似空肠弯曲菌经不同配比的基质液处理后进行质谱鉴定, 通过分析鉴定概率值及其特征峰的信号强度来评价不同配比基质液对空肠弯曲菌鉴定的影响, 并与16S rRNA鉴定结果进行比较。结果 通过16S rRNA与MALDI-TOF-MS 2种鉴定结果一致, 获得MALDI-TOF-MS鉴定空肠弯曲菌的最佳质谱基质液配比V乙醇:V乙腈:V水=1:1.5:1, 2.5% α-氰-4-羟基肉桂酸, 5.0%三氟乙酸, 鉴定概率值达99.9%。结论 致病菌的前处理与优化基质液配比可以提高基质辅助激光解析电离-飞行时间质谱鉴定的概率值。

英文摘要:

      Objective To establish a method for rapid identification of Campylobacter jejuni in food and beverage by matrix assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS). Methods The suspected Campylobacter jejuni isolated from the food and beverage samples was treated with different ratios of matrix liquids and subjected to mass spectrometry identification, the effect of different ratios of matrix liquid on the identification of Campylobacter jejuni was evaluated by analyzing the identification probability value and the signal intensity of the characteristic peak, and compared with 16S rRNA identification results. Results The identification results of 16S rRNA and MALDI-TOF-MS were consistent. The optimal mass spectrometry matrix solution ratio of Vethanol:Vacetonitrile:Vwater=1:1.5:1, 2.5% α-cyano-4-hydroxycinnamic acid, 5.0% trifluoroacetic acid was obtained for the identification of Campylobacter jejuni by MALDI-TOF-MS. The identification probability value was 99.9%. Conclusion Pretreatment of pathogenic bacteria and optimization of matrix liquid ratio can increase the probability value of matrix-assisted laser desorption ionization-time-of-flight mass spectrometry identification.