Cleaving Ergot Alkaloids by Hydrazinolysis-A Promising Approach for a Sum Parameter Screening Method

Area of Science:

• Food Science
• Analytical Chemistry
• Mycotoxicology

Background:

• Ergot alkaloids are prevalent mycotoxins from *Claviceps* fungi, contaminating food and feed globally.
• These toxins are structurally diverse, sharing an ergoline backbone, and typically quantified individually.
• Current methods require summing individual ergot alkaloid values for total content determination.

Purpose of the Study:

• To develop a simultaneous screening method for all ergot alkaloids.
• To convert diverse ergot alkaloids into a single homogeneous structure (a lysergic acid derivative).
• To compare acidic esterification and hydrazinolysis for efficient alkaloid cleavage.

Main Methods:

• Comparison of acidic esterification and hydrazinolysis using dihydroergocristine as a model compound.
• Optimization of hydrazinolysis reaction conditions, including the effect of ammonium iodide.
• Application of the optimized method to a mixture of major ergot alkaloids.

Main Results:

• Acidic esterification was unsuitable due to long reaction times and oxidation sensitivity.
• Hydrazinolysis achieved quantitative yields within 40–60 minutes, allowing parallel sample processing.
• Ammonium iodide addition was found to increase the hydrazinolysis reaction rate.
• Hydrazinolysis effectively cleaved ergopeptines but minimally affected ergometrine/-inine.

Conclusions:

• Hydrazinolysis is a suitable and efficient method for cleaving ergot alkaloids.
• This cleavage facilitates the development of a sum parameter screening method for total ergot alkaloids in food and feed.
• The method shows promise for rapid and comprehensive detection of ergot alkaloid contamination.