Zuberovic Muratovic Aida, Tröger Rikard, Granelli Kristina, Hellenäs Karl-Erik
Science Department, National Food Agency, Box 622, SE-751 26 Uppsala, Sweden.
Toxins (Basel). 2014 Dec 11;6(12):3326-35. doi: 10.3390/toxins6123326.
A single laboratory validation study of a rapid and sensitive quantitative method for the analysis of cereulide toxin produced by Bacillus cereus using ultra high performance liquid chromatography-electrospray-tandem mass spectrometry is presented. The analysis of this cyclic peptide toxin was validated for pasta and rice samples using a newly presented synthetic cereulide peptide standard, together with 13C6-cereulide that previously have not been commercially available. The use of cereulide standard was also compared to the most frequently used surrogate standard, the antibiotic valinomycin. The performance of the method was evaluated by analyzing spiked sample pools from different types of rice and pasta, as well as 21 individual rice and pasta samples from differently prepared meals. Inoculation of samples with three cereulide toxin-producing strains of Bacillus cereus was finally used to mimic naturally contaminated foods. The quantification range of the method was 1-500 ng/g (R2 = 0.999) and the limits of detection and quantification were 0.1 and 1 ng/g, respectively. The precision varied from 3% to 7% relative standard deviation and the trueness from -2% to +6% relative bias at different concentration levels in cooked rice and pasta.
本文介绍了一项针对蜡样芽孢杆菌产生的cereulide毒素分析的快速灵敏定量方法的单一实验室验证研究，该方法采用超高效液相色谱-电喷雾串联质谱法。使用新推出的合成cereulide肽标准品以及之前未商业化的13C6-cereulide，对意大利面和大米样品中的这种环肽毒素分析进行了验证。还将cereulide标准品的使用与最常用的替代标准品抗生素缬氨霉素进行了比较。通过分析不同类型大米和意大利面的加标样品池以及来自不同烹饪餐食的21份大米和意大利面单个样品，评估了该方法的性能。最后，用三种产生cereulide毒素的蜡样芽孢杆菌菌株接种样品，以模拟天然污染的食品。该方法的定量范围为1-500 ng/g（R2 = 0.999），检测限和定量限分别为0.1和1 ng/g。在煮熟的大米和意大利面中，不同浓度水平下的精密度相对标准偏差在3%至7%之间，真实性相对偏差在-2%至+6%之间。
