Development and validation of an LC-MS/MS method for the detection of phomopsin A in lupin and lupin-containing retail food samples from the Netherlands

Abstract

Phomopsins (PHO) are mycotoxins produced by the fungus Diaporthe toxica (also referred to as Phomopsis leptostromiformis). Lupin is the most important host crop for this fungus and PHO are suspected as cause of lupinosis, a deadly liver disease, in sheep. Lupin is currently in use to replace genetically modified soy in many food products available on the European market. However, a validated method for analysis of PHO is not available until now. In this work, a dilute-and-shoot LC-MS/MS-based method was developed for the quantitative determination and identification of phomopsin A (PHO-A) in lupin and lupin-containing food. The method involved extraction by a mixture of acetonitrile/water/acetic acid (80/20/1 v/v), dilution of the sample in water, and direct injection of the crude extract after centrifugation. The method was validated at 5 and 25 µg PHO-A kg(-1) product. The average recovery and RSD obtained were 79% and 9%, respectively. The LOQ (the lowest level for which adequate recovery and RSD were demonstrated) was 5 µg PHO-A kg(-1). Identification of PHO-A was based on retention time and two transitions (789 > 226 and 789 > 323). Using the average of solvent standards from the sequence as a reference, retention times were all within ± 0.03 min and ion ratios were within ± 12%, which is compliant with European Union requirements. The LOD (S/N = 3 for the least sensitive transition) was 1 µg PHO-A kg(-1) product. Forty-two samples of lupin and lupin-containing food products were collected in 2011-2012 from grocery stores and internet shops in the Netherlands and analysed. In none of the samples was PHO-A detected.

Mycotoxins—Biomonitoring and Human Exposure

“…Such data sets are useful in aiming the assessment of dietary exposure to certain mycotoxin in the general population [225,226]. The major EU institution for such assessments is the European Food Safety Authority (EFSA), which formed the Comprehensive European Food Consumption Database, also called EFSA Comprehensive Database [227]. Global assessments are done by the Food and Agriculture Organisation (FAO) of the United Nations.…”

Intestinal toxicity of the masked mycotoxin deoxynivalenol-3-β-d-glucoside

“…The authors observed that D3G was ineffective in evoking splenic cytokine or chemokine mRNA responses. Because D3G is poorly absorbed, the intestine can be a target for this toxin (De Nijs et al 2012;Nagl et al 2012Nagl et al , 2014.…”

Detection of a Toxic Methylated Derivative of Phomopsin A Produced by the Legume-Infesting Fungus Diaporthe toxica

“…9 Several studies have been carried out to gather information about the occurrence of phomopsins and to improve analytical techniques. 10,11 It has been recently shown that D. toxica has the potential to grow and produce toxins on other legumes, e.g., peas and beans. 12 The main toxin, phomopsin A (PHO-A), is often accompanied by small amounts of phomopsin B (PHO-B).…”