*Article* **Cleaving Ergot Alkaloids by Hydrazinolysis—A Promising Approach for a Sum Parameter Screening Method**

**Maximilian Kuner 1, Susanne Kühn 2, Hajo Haase 3, Klas Meyer <sup>1</sup> and Matthias Koch 1,\***


**Abstract:** Ergot alkaloids are mycotoxins formed by fungi of the *Claviceps* genus, which are some of the most common contaminants of food and feed worldwide. These toxins are a structurally heterogeneous group of compounds, sharing an ergoline backbone. Six structures and their corresponding stereoisomers are typically quantified by either HPLC-FLD or HPLC-MS/MS and the values subsequently summed up to determine the total ergot alkaloid content. For the development of a screening method targeting all ergot alkaloids simultaneously, the alkaloids need to be transferred to one homogeneous structure: a lysergic acid derivative. In this study, two promising cleaving methods—acidic esterification and hydrazinolysis—are compared, using dihydroergocristine as a model compound. While the acidic esterification proved to be unsuitable, due to long reaction times and oxidation sensitivity, hydrazinolysis reached a quantitative yield in 40-60 min. Parallel workup of several samples is possible. An increasing effect on the reaction rate by the addition of ammonium iodide was demonstrated. Application of hydrazinolysis to a major ergot alkaloid mix solution showed that all ergopeptines were cleaved, but ergometrine/-inine was barely affected. Still, hydrazinolysis is a suitable tool for the development of a sum parameter screening method for ergot alkaloids in food and feed.

**Keywords:** ergot alkaloids; sum parameter method; hydrazinolysis; esterification

**Key Contribution:** Acidic esterification and hydrazinolysis were optimized and evaluated for a possible ergot alkaloid routine sum parameter screening method. Hydrazinolysis was found to be highly suitable.
