该研究探讨了基质辅助激光解吸电离飞行时间质谱仪快速鉴别产呕吐毒素蜡样芽胞杆菌的方法。通过对标准品进行分析，重新对特征峰进行定位并测定其灵敏度，并用正交试验分析不同培养条件下检验结果的差异，用优化后的培养条件对49株野生蜡样芽胞杆菌及3株标准菌株进行特异性检验。研究表明，MALDI-TOF MS可检测到产呕吐毒素蜡样芽胞杆菌中呕吐毒素相应m/z值为1 175的[M+Na]+和m/z值为1 191的[M+K]+加合物特征峰，具有较高的灵敏度（0.01 μg/mL），经极差分析显示，选用MYP培养基30 ℃培养12 h后的菌落能获得最稳定、响应值高（>104）的检验结果；方法应用验证表明，49株野生菌株中2株含ces基因的蜡样芽胞杆菌均检出，其余未含有ces基因的菌株均未检出。该研究建立的MALDI-TOF MS检测方法能直接快速准确检出产呕吐毒素蜡样芽胞杆菌，该方法检测特异性强（100%），灵敏度高（0.01 μg/mL），对于食品安全事故快速精准分析研判有重要的意义。

The rapid identification of cereulide-producing Bacillus cereus by matrix-assisted laser desorption ionization time-off-light mass spectrometry was investigated. The characteristic peak was located and the sensitivity was determined through analyzing the standard substances. The differences between the test results under different culture conditions were analyzed by the orthogonal test, and the specificity of 49 wild B. cereus and 3 standard strains were tested under the optimized culture conditions. The results showed that MALDI-TOF MS could detect the characteristic peaks of [M+Na]+ and [M+K]+ adducts with 1 175 and 1 191 m/z values respectively, corresponding to the cereulide produced in B. cereus, with a high sensitivity (0.01 μg/mL). The range analysis showed that the typical colony cultured in MYP medium at 30 ℃ for 12 hours could lead to the most stable test result with the highest response value (>104). The method application verification revealed that among 49 wild strains, 2 Bacillus cereus strains containing ces gene were detected, whilst the other strains without the ces gene were not detected. The MALDI-TOF MS detection method established in this study can directly, rapidly and accurately detect cereulide-producing B. cereus. This method has strong specificity (100%) and high sensitivity (0.01 μg/mL). Thus, it is of great significance for rapid and accurate analysis and judgment of food safety accidents.

广州市市场监督管理局科技项目（2020kj53）；广东省市场监督管理局科技项目（2020CS01）