Simultaneous Determination of Alternaria Toxins, Ergot Alkaloid Epimers , and Other Major Mycotoxins in Various Food Matrices by LC MS/MS

Significance of the Topic

Various fungal genera produce regulated and emerging mycotoxins that can contaminate a wide range of foodstuffs, posing health risks to consumers. A unified analytical strategy is essential to monitor multiple toxin classes such as Alternaria metabolites, ergot alkaloids with epimers, and other major mycotoxins efficiently.

Objectives and Study Overview

This study aimed to establish and validate a simplified LC-MS/MS workflow capable of simultaneous quantification of 38 mycotoxins in diverse food matrices, including infant wheat cereal, raw peanut, tomato puree, and blended flour. The goal was to achieve high sensitivity, accuracy, and throughput for regulatory compliance and quality control laboratories.

Methodology and Instrumentation

Sample preparation employed 80:20 acetonitrile:water extraction acidified with 0.5% formic acid (omitted for tomato puree), followed by horizontal mixing, centrifugation, evaporation under a gentle nitrogen stream at 45 °C, reconstitution in 50:50 water:methanol, and filtration through a 0.2 µm PTFE membrane.
Chromatography used a Restek Raptor Biphenyl column (2.7 µm, 100 mm × 2.1 mm) at 60 °C with a gradient of 0.05% formic acid in water and methanol over an 11-minute run at 0.4 mL/min.
Detection was performed on a Waters Xevo TQ-S with Acquity UPLC under positive ESI using scheduled MRM transitions.

Main Results and Discussion

• Chromatographic performance: All ergot alkaloid epimer pairs were resolved within an 11-minute cycle, with acceptable peak shapes after column equilibration.
• Linearity: Quadratic 1/x-weighted calibration curves over 0.4–400 µg/kg yielded r²>0.997 for most analytes and deviations <30%.
• Limit of quantification: 0.4 µg/kg for the majority of toxins, meeting stringent regulatory thresholds.
• Accuracy and precision: Recoveries ranged from 70% to 120% (except citrinin in solids) with RSD values below 20% across three fortification levels and four matrices.
• Matrix effects: Formic acid improved fumonisin recovery in solid samples but reduced citrinin extraction; tomato puree achieved balanced recoveries without acid.
• Limitations: Nivalenol could not be quantified in cereal and certain low-level analytes were challenged by matrix interference.

Benefits and Practical Applications

• Streamlined multi-mycotoxin analysis reduces sample preparation time and analytical costs.
• High throughput and broad applicability support routine monitoring in food safety and QA/QC settings.
• Matrix-matched calibration ensures accurate quantitation across diverse commodities.

Future Trends and Opportunities

• Integration with high-resolution mass spectrometry for non-target screening and retrospective data analysis.
• Automation of sample handling to enhance reproducibility and reduce manual errors.
• Expansion to additional food matrices and emerging mycotoxins.
• Development of isotopically labeled standards to further correct matrix effects.

Conclusion

The developed LC-MS/MS method demonstrates robustness, sensitivity, and efficiency for simultaneous determination of an extensive panel of mycotoxins in varied food matrices, supporting regulatory compliance and improved food safety surveillance.

References

• Liang S-H, York J, Konschnik J, Majer H, Steimling J; Restek Corporation. Simultaneous Determination of Alternaria Toxins, Ergot Alkaloid Epimers, and Other Major Mycotoxins in Various Food Matrices by LC-MS/MS.