Homoarginine, β-ODAP, and asparagine contents of grass pea landraces cultivated in Turkey

The seeds of grass pea (Lathyrus sativus L.), a drought tolerant crop, were analysed for quantitative determination of the free amino acids β-N-oxalyl-l-α,β-diaminopropionic acid (β-ODAP), homoarginine and asparagine by a simple and fast capillary electrophoretic method. In boric acid (80 mM, pH 8.0) running buffer system, not only were α and β-ODAP successfully separated, but also an efficient sample stacking was achieved during hydrodynamic sample introduction. The validated method was used for quantification of β-ODAP, homoarginine and asparagine in seed extracts of 52 Lathyrus local landraces from various regions of Turkey and one released cultivar. The concentration ranges of amino acids were found as 0.21–1.27% (w/w) for homoarginine, 0.10–0.87% (w/w) for β-ODAP and 0.006–0.47% (w/w) for asparagine. A positive correlation between homoarginine and β-ODAP quantities in seeds of 53 Lathyrus local landraces was shown to exist (r2 = 0.649).