Targeted LC-MS/MS combined with multilocus DNA metabarcoding as a combinatory approach to determine the amount and the source of pyrrolizidine alkaloids contamination in popular cooking herbs, seeds, spices and leafy vegetables

Sorting out the plants responsible for a contamination with pyrrolizidine alkaloids in spice seeds by means of LC-MS/MS and DNA barcoding: Proof of principle with cumin and anise spice seeds

“…Samples were selected based on the targeted LC-MS/MS analysis for PA/PANOs of Picron et al (2021) . One highly contaminated cumin sample (sample S06) and one highly contaminated green anise sample (sample S57) were selected, as well as one cumin (S23) and one green anise (S53) sample with low PA/PANO content.…”

“…The PA/PANOs extraction protocol for the ground seed material was performed as described by Picron et al, 2021 . Briefly, 0.5 g (±0.005 g) of homogenized sample was weighed into a 50 mL polypropylene tube to which 20 mL of 0.05 M H 2 SO 4 were added.…”

“…Moreover, the predominant type of PA/PANOs present in these samples belonged to the heliotrine-type PA/PANO, suggesting a contamination with a plant species belonging to the Heliotropium genus of the Boraginaceae plant family ( El-Shazly and Wink, 2014 , Mädge et al, 2020 , Picron et al, 2021 ). This hypothesis was confirmed by DNA metabarcoding which demonstrated the presence of DNA of a plant species belonging to the Heliotropium genus in these seed samples ( Picron et al, 2021 ).…”

“…Therefore, spices are increasingly subjected to systematic quality control programs while analytical methodologies for previously unassessed possible contaminants are being generated ( Modupalli et al, 2021 ). Very recently, the occurrence of pyrrolizidine alkaloids (PAs) and their corresponding N-oxides (PANOs), originating from a contamination with this type of phytotoxin producing plant species, was assessed in different herbal matrices, including spices ( Chung & Lam, 2017 , Kaltner et al, 2020 , Picron et al, 2021 ).…”

“…Recently, two independent studies have shown that at least one third of the analyzed cumin and green anise spice seeds samples surpassed the set threshold value of 400 µg/kg ( Kaltner et al, 2020 , Picron et al, 2021 ). Moreover, the predominant type of PA/PANOs present in these samples belonged to the heliotrine-type PA/PANO, suggesting a contamination with a plant species belonging to the Heliotropium genus of the Boraginaceae plant family ( El-Shazly and Wink, 2014 , Mädge et al, 2020 , Picron et al, 2021 ). This hypothesis was confirmed by DNA metabarcoding which demonstrated the presence of DNA of a plant species belonging to the Heliotropium genus in these seed samples ( Picron et al, 2021 ).…”