Agronomic Characterization and α- and β-ODAP Determination through the Adoption of New Analytical Strategies (HPLC-ELSD and NMR) of Ten Sicilian Accessions of Grass Pea

Abstract

Ten accessions of grass pea (Lathyrus sativus L.) from different Sicilian sites, cultivated in the same environmental conditions, were analyzed for their morphological and productive parameters and for the content of two non-protein amino acids: α- and β-ODAP (α- and β-N-oxalyl-l-α,β-diaminopropionic acid). The β-isomer is the neurotoxin responsible for the neuron disease known as lathyrism. This analysis was carried out using two common analytical methodologies never applied in their determination, an HPLC separation with evaporative light scattering (ELS) as detector, and nuclear magnetic resonance (NMR). The content of the two isomers falls in the range reported for these compounds: 0.42-0.74 and 2.69-4.59 g/kg for α- and β-ODAP, respectively; and the two methods yield comparable results. High productivity and a high protein content were detected in three Sicilian accessions. Low β-ODAP content was found to be linked to accessions with heavier seeds and those originating at lower altitudes.